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Keywords:

  • bladder hypersensitivity;
  • lower urinary tract symptoms;
  • symptom syndrome;
  • terminology;
  • urgency;
  • urinary incontinence

Abstract

  1. Top of page
  2. Abstract
  3. Introduction
  4. Lower urinary tract symptoms (LUTS)
  5. Frequency
  6. Urgency
  7. Urinary incontinence
  8. Bladder sensation
  9. Voiding symptoms
  10. Post micturition symptoms
  11. Pain
  12. Syndromes
  13. Measuring the frequency, severity and impact of lower urinary tract symptoms
  14. Physical examination
  15. Conditions
  16. Discussion
  17. Conclusions
  18. References

Abstract:  Terminology for lower urinary tract symptoms has been popularized since an extensive revision by the International Continence Society (ICS) in 2002, however the revision incurred significant confusion and inconvenience among the users. For example, distinction between night time frequency and nocturia is practically infeasible; urgency must be of sudden onset (persistent urgency is an invalid usage); terms are lacking for some types of urinary leakage; bladder filling and urge to void must be differentiated; symptom syndromes are not applicable to non-functional abnormality; a syndrome for bladder hypersensitivity is lacking; polyuria is not defined properly. This review has detailed definitions and confusions related to the latest version, and suggested possible solutions for a better vocabulary of words.


Introduction

  1. Top of page
  2. Abstract
  3. Introduction
  4. Lower urinary tract symptoms (LUTS)
  5. Frequency
  6. Urgency
  7. Urinary incontinence
  8. Bladder sensation
  9. Voiding symptoms
  10. Post micturition symptoms
  11. Pain
  12. Syndromes
  13. Measuring the frequency, severity and impact of lower urinary tract symptoms
  14. Physical examination
  15. Conditions
  16. Discussion
  17. Conclusions
  18. References

As exemplified by the story of the Tower of Babel, linguistic ambiguity makes mutual understanding difficult, leading to confusion. In the treatment and research of lower urinary tract dysfunctions, a lack of uniformity in technical terms may also cause confusion and prevent scientific progress or appropriate diagnosis and treatment.

For terminology related to the function and dysfunction of the lower urinary tract, the International Continence Society (ICS) has been conducting a series of endeavors aimed at uniformity since 1976,1 and the latest Report from the Standardization Sub-Committee was published in 2002.2 The Report may be regarded as a major revision and has been translated into Japanese.3 It is noteworthy that the Report has standardized lower urinary tract symptoms (LUTS) and related symptoms by classifying and describing them in detail. As the new terminology becomes commonly used, however, confusion has emerged among users of the terminology. This review article presents definitions and confusion related to the latest Report terminology, with possible solutions suggested.

Lower urinary tract symptoms (LUTS)

  1. Top of page
  2. Abstract
  3. Introduction
  4. Lower urinary tract symptoms (LUTS)
  5. Frequency
  6. Urgency
  7. Urinary incontinence
  8. Bladder sensation
  9. Voiding symptoms
  10. Post micturition symptoms
  11. Pain
  12. Syndromes
  13. Measuring the frequency, severity and impact of lower urinary tract symptoms
  14. Physical examination
  15. Conditions
  16. Discussion
  17. Conclusions
  18. References

Definition

The Report defines symptoms as the subjective indicator of a disease or change in condition as perceived by the patient, carer or partner. LUTS are divided into 3 groups: (i) storage symptoms, (ii) voiding symptoms, and (iii) post micturition symptoms, while related symptoms are classified into 4 additional main categories: (iv) symptoms associated with sexual intercourse, (v) symptoms associated with pelvic organ prolapse, (vi) genital and lower urinary tract pain, and (vii) symptom syndromes. It is confirmed that LUTS are defined from the individual's (mostly the patient's) perspective.

Confusion

Lower urinary tract symptoms may be considered an uncommon and redundant expression; the terms ‘voiding symptoms’ or ‘urinary symptoms’ are more commonly used with the same meaning. The standard terminology defined voiding symptoms exclusively as ‘symptoms during voiding’ and not for symptoms such as urinary incontinence. The term ‘lower urinary tract’ is scientifically more accurate than ‘voiding’. Despite inconsistency with common usage, ‘LUTS’ should be recommended at least for scientific communications.

Frequency

  1. Top of page
  2. Abstract
  3. Introduction
  4. Lower urinary tract symptoms (LUTS)
  5. Frequency
  6. Urgency
  7. Urinary incontinence
  8. Bladder sensation
  9. Voiding symptoms
  10. Post micturition symptoms
  11. Pain
  12. Syndromes
  13. Measuring the frequency, severity and impact of lower urinary tract symptoms
  14. Physical examination
  15. Conditions
  16. Discussion
  17. Conclusions
  18. References

Definition

The Report defines ‘increased daytime frequency’ as the complaint by the patient who considers that he/she voids too often by day. This term is equivalent to ‘pollakisuria’. ‘Nocturia’ is the complaint that the individual has to wake at night one or more times to void. In this context, day means from the time of waking in the morning to the time of going to bed at night, and night means from the time of going to bed at night to waking in the morning.

‘Increased daytime frequency’ is the complaint of the patient. Therefore, voiding five times is regarded as a symptom if the patient considers it to be too frequent, but even voiding 15 times is not regarded as a symptom if the patient does not consider it to be too frequent. In contrast, nocturia is considered to be positive if the patient awakes even once during sleep and goes to the toilet. By definition, voids before the individual has gone to sleep in bed or voids in the early morning which prevent the individual from getting back to sleep are not regarded as nocturia. Waking from sleep not due to a need to void (followed by voiding for convenience) is not classed as nocturia either. These voids that do not fit into the definition of ‘nocturia’ are included in ‘night-time frequency’.

Confusion

There is a lack of symmetry in both the term and definition between ‘daytime frequency’ and ‘night-time frequency’. Frequent urination during the daytime is defined by the explanatory term ‘increased daytime frequency’, but frequent urination during the night-time is defined by the single word ‘nocturia’ but not by ‘increased night-time frequency.’ Furthermore, with regard to the definition, increased daytime frequency is based on the patient's complaint, while nocturia is based on the number of voids (one or more times). In addition, the definition of nocturia may be excessively strict. Nocturia does not include voiding between the time of going to bed and the time of falling asleep at night and between waking up and rising in the morning. Voiding when the individual is awakened for reasons other than the desire to void (e.g. noise) is apparently not included in nocturia (Fig. 1). Nocturia in this strict sense would be physiologically different from ‘night-time voiding.’ However, into which category should voiding that occurs while the individual is dozing, i.e. half asleep, early in the morning be placed? Can reasons for waking up be clearly divided into a desire to void and other reasons? The definition of nocturia by the Report narrows, perhaps unreasonably, the meaning of the term that has been used conventionally or commonly.4–6

image

Figure 1. Newly defined nocturia does not include voiding from the time of going to bed until the time of falling asleep, waking-and-voiding not due to a desire to void, or voiding from the time of waking until the time of rising from bed.

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If we are faithful to the patient's words ‘I need to go to the bathroom too often’, ‘increased frequency’ would be a good expression and should be described as such regardless of the actual number of voids. Naturally increased frequency during the day is ‘increased daytime frequency’ and during the night is ‘increased night-time frequency.’ Pollakisuria and nocturia could be used as synonyms of increased daytime frequency and increased night-time frequency, respectively. Night-time in this context would mean the period from going to bed with the intention of sleeping until waking with the intention of rising. Night-time voiding excludes both the last void before going to bed at night and the first void in the morning after rising. Importantly, this definition of night time (conversely the definition of daytime) is compatible with that used in a later section of the Report (the micturition record section).

Urgency

  1. Top of page
  2. Abstract
  3. Introduction
  4. Lower urinary tract symptoms (LUTS)
  5. Frequency
  6. Urgency
  7. Urinary incontinence
  8. Bladder sensation
  9. Voiding symptoms
  10. Post micturition symptoms
  11. Pain
  12. Syndromes
  13. Measuring the frequency, severity and impact of lower urinary tract symptoms
  14. Physical examination
  15. Conditions
  16. Discussion
  17. Conclusions
  18. References

Definition

The Report defined urgency as the complaint of a sudden compelling desire to pass urine, which is difficult to defer. Two phrases, ‘a compelling desire to void’ and ‘difficult to defer’ mean virtually the same, almost forced or having to go. ‘Sudden’ in this definition indicates ‘abrupt’, which means more ‘unexpected’ than ‘hasty’. Therefore, urgency would be ‘a strong desire to void with an abrupt onset’. Healthy people would feel ‘a strong desire to void’ if, for example, they have not been able to go to the toilet for a long time. However, in healthy people, the desire to void increases gradually to a strong level while they cannot (or do not) go to the toilet.

Confusion

Urgency by definition may well describe a sensation perceived by patients with overactive bladder syndrome,7 however it is uncertain whether urgency is an all-or-none abnormal sensation8 or a continuum or an extreme form of a normal sensation, the ‘desire to void’.9,10 In addition it does not describe ‘the strong desire to void’ perceived by patients with other diseases or conditions. For example, patients with interstitial cystitis feel an imperative need to void, but this feeling is different from the urgency given in the Report definition. It would be closer to discomfort or pain than to imminent leakage and more incessant than abrupt.11,12 The strong desire to void that healthy people would feel if they keep holding urine in the bladder for a long time is not of abrupt onset but may be complained of as urgency by them. ‘Urgency’ is urinary urgency, and it has been conventionally used simply to imply ‘a strong urge to void’.1 The new urgency defined by the Report has lost part of its conventional meaning due to an exact qualifier ‘sudden’ (Table 1).

Table 1.  Conventional urgency and new urgency
  1. The newly defined ‘urgency’ has lost its conventional meaning because of the qualifier ‘sudden’.

Conventional urgencyA strong desire/urge to urinate
New urgencyA strong desire to urinate with an abrupt onset
What was lost when the new definition of urgency was adoptedA strong desire to urinate without an abrupt onset (anticipated, gradually increasing, incessant, with a vague onset)

A sudden onset of the compelling desire to void is possible, as involuntary contraction during filling cystometry appears suddenly, although involuntary contraction is neither highly specific nor sensitive to overactive bladder syndrome.13 Questionnaires to assess urgency, however, do not address how suddenly the sensation of desire appears but how hastily you have to void or how long you can hold it.8,9,14–17 The symptom addressed by a question on how long you can hold micturition would be the fear of leakage rather than the sudden onset of the desire to void.

To quell the confusion, defining urgency simply and more inclusively as ‘a strong urge to void’ or ‘a pressing need to urinate’, for example, is suggested. Urgency with sudden onset, if it exists, could be expressed by a term such as ‘sudden urgency’. Symptoms characteristic to overactive bladder syndrome may be sudden urgency with fear of leakage.

Urinary incontinence

  1. Top of page
  2. Abstract
  3. Introduction
  4. Lower urinary tract symptoms (LUTS)
  5. Frequency
  6. Urgency
  7. Urinary incontinence
  8. Bladder sensation
  9. Voiding symptoms
  10. Post micturition symptoms
  11. Pain
  12. Syndromes
  13. Measuring the frequency, severity and impact of lower urinary tract symptoms
  14. Physical examination
  15. Conditions
  16. Discussion
  17. Conclusions
  18. References

Definition

The Report defines urinary incontinence as the complaint of any involuntary leakage of urine. Seven categories of urinary incontinence, i.e. stress urinary incontinence, urge (preferably, urgency18) urinary incontinence, mixed urinary incontinence, enuresis, nocturnal enuresis, continuous urinary incontinence, and other types of urinary incontinence, are classified and mentioned.

The conventional definition of urinary incontinence was ‘involuntary loss of urine that is a social or hygienic problem’.1 Whether leakage of urine is a social or hygienic problem varies according to a patient's perception and culture, but nevertheless poses a problem in scientific discussion. The removal of this qualifier appears to be an improvement as far as clarity is concerned. It is also recommended to evaluate quality of life by using appropriate questionnaires. The recommendation is that the objective fact of urine leakage and the subjective aspect (social or hygienic problems) should be evaluated separately. The qualifier ‘involuntary’ is kept in the new definition, which means not voluntary, that is, unintentional, without noticing or, in a stronger sense, contrary to intention.

Confusion

With regard to ‘involuntary’: for an action to be involuntary, there must be a will present that enables the person to perform a voluntary (i.e. intentional) action. In this case, is ‘leakage in the absence of will’ the same as incontinence? ‘In the absence of will’ means, for example, while the person is unconscious or asleep. Also, how should ‘voluntary leakage of urine’ be interpreted? ‘Voluntary leakage of urine’ is, for example, intentional urination at socially unacceptable places (e.g. on a street), or intentional urination at places mistaken for the toilet due to recognition impairment. The Report provides no terms for such conditions. Some of these conditions may be described as enuresis, which is defined as ‘any involuntary loss of urine’. How does urinary incontinence (involuntary leakage of urine) differ from enuresis (involuntary loss of urine)? To be more meticulous about the term ‘involuntary’, the question arises as to whether normal urination is voluntary. Certainly, normal urination is initiated voluntarily. However, once urination starts, bladder contraction occurs involuntarily. So, normal urination can be interpreted as enuresis with a voluntary onset.

To remove confusion, it may be useful to define a condition that is not urinary incontinence (continence). Continence would be ‘the passage of urine at socially acceptable places (usually at the toilet)’. Then, a condition of non-continence would be the ‘passage of urine at places other than socially acceptable places’, which would correspond to ‘urinary leakage’ as a general term. Here, the phrase ‘social problem’, removed in this revision, emerges again. In other words, urination is a social action, and whether a person appropriately manages it cannot be discussed outside the context of social conditions. ‘Non-continence’ may occur in the absence of will or voluntarily in the presence of will. ‘Enuresis’ would be an appropriate term for such a passage of urine. ‘Non-continence’ that occurs involuntarily in the presence of will is urinary incontinence as defined by the Report (Table 2).

Table 2.  Classification of urinary leakage (non-continence)
Standardization reportWillVoluntariness (intention)Suggested classification 
  1. Urinary leakage (non-continence) is the passage of urine at places other than socially acceptable places such as the toilet. It is classified into enuresis (urinary leakage in the absence of will or by intention) and urinary incontinence (urinary leakage against intention).

No corresponding terms existNo Yes– Voluntary (by intention)Enuresis (Urinary leakage in the absence of will or by intention)• Non-continence • Urinary leakage • Urinary incontinence in a broad sense
Urinary incontinence The complaint of any involuntary leakage of urineYesInvoluntary (against intention)Urinary incontinence (Urinary leakage against intention)Passage of urine at places other than socially acceptable places such as the toilet

The Report does not recommend the term ‘overflow urinary incontinence’, nor does it mention several other types of incontinence. Since these types of incontinence are descriptive of a condition, not a symptom, they are not to be included in symptom categories, however they are used clinically and should be defined explicitly (for example as in Table 3).

Table 3.  Additional types of incontinence (characterized by factors other than symptoms)
Total urinary incontinenceUrinary leakage in which most urine is passed as urinary leakage
Reflex urinary incontinenceUrinary passage as an autonomous micturition reflex of the sacral micturition center.
Functional urinary incontinenceUrinary leakage caused by impairment of functions other than lower urinary tract function (i.e. impaired activity of daily living or cognitive function).
Overflow urinary incontinenceUrinary leakage associated with urinary retention.

Bladder sensation

  1. Top of page
  2. Abstract
  3. Introduction
  4. Lower urinary tract symptoms (LUTS)
  5. Frequency
  6. Urgency
  7. Urinary incontinence
  8. Bladder sensation
  9. Voiding symptoms
  10. Post micturition symptoms
  11. Pain
  12. Syndromes
  13. Measuring the frequency, severity and impact of lower urinary tract symptoms
  14. Physical examination
  15. Conditions
  16. Discussion
  17. Conclusions
  18. References

Definition

The Report classifies proper sensation of the urinary bladder into normal, increased, reduced and absent. Normal sensation is defined as the awareness of the bladder filling and the increasing sensation up to a strong desire to void. Increased sensation is defined as an early and persistent desire to void; however, it is not mentioned whether a sensation of the bladder filling is also experienced. Reduced sensation refers to a lack of definite desire to void despite the awareness of the bladder filling, and absent sensation means no sensation of either bladder filling or a desire to void.

Bladder sensation during filling cystometry is also defined in the Report. Normal sensation is a sequence of a first sensation of bladder filling followed by a first desire to void (a desire to void at the next convenient moment) and then by a strong desire to void (a persistent desire to void without fear of leakage). Increased sensation refers to an early first sensation of bladder filling (or an early desire to void) and/or an early strong desire to void, which occurs at a low bladder volume and which persists. The terms ‘reduced’ and ‘absent’ mean diminished and no ‘sensation’, respectively.

Confusion

There is a disagreement among these terms when they are used as symptoms or as cystometric terms. The meanings of ‘normal’ and ‘absent’ are almost identical; however, the meanings of ‘increased’ and ‘reduced’ slightly differ with regard to the bladder filling (Table 4). At cystometry bladder filling occurs early in increased sensation and is diminished in reduced sensation. As a symptom bladder filling is not mentioned in increased sensation (possibly occurs early, simultaneously with desire to void, or never) and is felt in reduced sensation.

Table 4.  Bladder sensation as symptoms and cystometric terms
  Sensation of bladder fillingDesire to void
NormalSymptomFelt prior to a desire to voidFelt from weakly to strongly
Cystometry  
IncreasedSymptomNot describedOccurs early (at low bladder volume) and persists
CystometryOccurs early 
ReducedSymptomFeltNot felt definitely or diminished
CystometryDiminished 
AbsentSymptomAbsentAbsent
Cystometry  

During filling cystometry, water is infused into the urinary bladder at a non-physiological rate, with a catheter inserted in the urethra and bladder, however it may be erroneously taken for granted that the sensation of the bladder filling that is experienced early during cystometry is perceived prior to the desire to void under non-cystometric settings. It is doubtful that normal subjects feel the sensation of the bladder filling to be a clearly different sensation from the desire to void. When they have the ‘sensation of the bladder filling’, it would actually refer to the initial desire to void.10,19 This may explain why increased sensation as a cystometric term refers to the early perception of the bladder filling, while that as a symptom does not mention bladder filling. The definition stating that the reduced sensation as a symptom is accompanied by the sensation of the bladder filling despite an unclear desire to void is based on a presumption that a large amount of urine in the bladder should be felt as a sensation of the bladder filling.

Symptom terms and cystometric terms need not be identical. It would be acceptable for different terms to be used for cystometry, however symptom terms should be easy for patients to understand. Bladder sensations as symptoms should not be described in terms of the bladder filling but in relationship to the urge to void and the bladder volume10,19 (Table 5).

Table 5.  Suggested bladder sensation as symptoms
TermMeaning
NormalNo desire to void is felt when the bladder volume is small. As the volume increases, the desire to void begins to be felt and increases gradually. It is felt intermittently when it is weak. It is felt continuously when it is strong.
IncreasedThe desire to void is felt even when the bladder volume is small. It persists with varying intensity and gradually increases.
ReducedNo definite desire to void is felt even when the bladder volume is large
AbsentNo desire to void is felt even when the bladder volume is large.

Voiding symptoms

  1. Top of page
  2. Abstract
  3. Introduction
  4. Lower urinary tract symptoms (LUTS)
  5. Frequency
  6. Urgency
  7. Urinary incontinence
  8. Bladder sensation
  9. Voiding symptoms
  10. Post micturition symptoms
  11. Pain
  12. Syndromes
  13. Measuring the frequency, severity and impact of lower urinary tract symptoms
  14. Physical examination
  15. Conditions
  16. Discussion
  17. Conclusions
  18. References

Definition

The Report describes several ‘voiding symptoms’, including slow stream, splitting or spraying, intermittency, hesitancy, straining, and terminal dribbling. These are readily understood literally and consistent with common usage.

Confusion

A concern is felt for the use of straining, which is defined as ‘the muscular effort used to initiate, maintain or improve the urinary stream’. Effort can be used at any phase of voiding: initial, halfway or terminal. The difference of phase when effort is applied may be different symptomatically or physiologically in women.20 In men the sixth question of the American Urological Association symptom index for benign prostatic hyperplasia pertains only to abdominal straining at initiating micturition.21 Sub-classification of straining according to voiding phases may be needed.

Post micturition symptoms

  1. Top of page
  2. Abstract
  3. Introduction
  4. Lower urinary tract symptoms (LUTS)
  5. Frequency
  6. Urgency
  7. Urinary incontinence
  8. Bladder sensation
  9. Voiding symptoms
  10. Post micturition symptoms
  11. Pain
  12. Syndromes
  13. Measuring the frequency, severity and impact of lower urinary tract symptoms
  14. Physical examination
  15. Conditions
  16. Discussion
  17. Conclusions
  18. References

Definition

The Report creates ‘post micturition symptoms’ as a new term. It refers to the feeling of incomplete emptying and post micturition dribble. The new term is welcome, because there has been inconsistency in classifying the feeling of incomplete emptying as voiding symptoms or storage symptoms.

Confusion

There is no mention of whether the feeling of incomplete emptying is the same as the feeling of residual urine, although these two would be identical as symptoms.

Pain

  1. Top of page
  2. Abstract
  3. Introduction
  4. Lower urinary tract symptoms (LUTS)
  5. Frequency
  6. Urgency
  7. Urinary incontinence
  8. Bladder sensation
  9. Voiding symptoms
  10. Post micturition symptoms
  11. Pain
  12. Syndromes
  13. Measuring the frequency, severity and impact of lower urinary tract symptoms
  14. Physical examination
  15. Conditions
  16. Discussion
  17. Conclusions
  18. References

Definition

The Report characterizes seven types of pain by location: bladder pain, urethral pain, vulval pain, vaginal pain, scrotal pain, perineal pain, and pelvic pain. Some of them may have no direct relationship to voiding, however pain felt in the genital organs and lower urinary tract should be considered within the scope of LUTS.

According to The International Association for the Study of Pain (IASP), ‘pain is an unpleasant sensory and emotional experience associated with actual or potential tissue damage or described in such damage’.22 Pain is an experience accompanied by an unpleasant sensation due to (or apparently attributable to) tissue damage and emotions such as fear, anger and sorrow. The Longman Dictionary of Contemporary English says ‘pain is the feeling you have when part of your body hurts’, a description which does not mention an emotional aspect of pain.

Confusion

At the beginning of this section, there is a statement that ‘pain, discomfort and pressure are part of a spectrum of abnormal sensations felt by the individual’. This statement is interpreted or misinterpreted to the effect that pain in a broad sense of the word would encompass discomfort and pressure. Discomfort and pressure may accompany emotional responses, thereby complying with the IASP definition of pain. It is suggested that the term ‘pain’ should be defined in its narrower and common sense to avoid confusion with other abnormal sensations.

Syndromes

  1. Top of page
  2. Abstract
  3. Introduction
  4. Lower urinary tract symptoms (LUTS)
  5. Frequency
  6. Urgency
  7. Urinary incontinence
  8. Bladder sensation
  9. Voiding symptoms
  10. Post micturition symptoms
  11. Pain
  12. Syndromes
  13. Measuring the frequency, severity and impact of lower urinary tract symptoms
  14. Physical examination
  15. Conditions
  16. Discussion
  17. Conclusions
  18. References

Definition

The Report defines syndromes as constellations, or varying combinations of symptoms, but not a precise diagnosis. Syndromes describe functional abnormalities for which a precise cause has not been identified. It is presumed that routine assessment has excluded obvious local pathologies. ‘Pain syndromes’ are classified into seven syndromes, each of which has one of seven types of pain according to the above-mentioned classification of pain. In particular, painful bladder syndrome is the suprapubic pain related to bladder filling, accompanied by other symptoms such as increased daytime and night-time frequency, in the absence of proven urinary infection or other obvious pathology. This syndrome is regarded as a preferable term to interstitial cystitis. Interstitial cystitis is a specific diagnosis and requires confirmation by typical cystoscopic and histological features. ‘Symptom syndromes’ are divided into ‘overactive bladder syndrome’ and ‘lower urinary tract symptoms suggestive of bladder outlet obstruction.’ Overactive bladder syndrome can be described as ‘urge syndrome’ or ‘urgency–frequency syndrome’, and is urodynamically suggestive of detrusor overactivity. ‘Lower urinary tract symptoms suggestive of bladder outlet obstruction’ is a term used when a man complains predominantly of voiding symptoms in the absence of obvious pathology other than possible outlet obstruction.

Confusion regarding concept

‘Syndromes’ is a new concept, which has three important conditions: (i) syndromes must have multiple symptoms; (ii) syndromes describe functional abnormalities (obvious local pathologies are excluded by routine clinical assessment); and (iii) ‘syndrome’ is not a precise diagnosis.

The first condition requiring multiple symptoms may be too rigid. It is not so important whether the patient has one or multiple symptoms, but rather that the symptom(s) cannot be explained by obvious pathology. ‘Syndrome with a single symptom’ sounds unnatural, however, and in fact many syndromes are featured with multiple symptoms. A possible solution would be a definition that a syndrome describes a combination of symptoms, without referring to the fact that the symptoms must be multiple.

The other two conditions may lead to more serious confusion; (i) routine clinical assessment may be variable among countries or districts; and (ii) symptoms attributable to non-functional disorders are not syndromes; patients with non-functional disorders that are undiagnosed by routine tests but first identified by non-routine tests are not compatible with the definition of syndromes. For example, if a patient with painful bladder syndrome is found by bladder hydrodistension and biopsy under anesthesia to have typical findings of interstitial cystitis, should this patient be diagnosed as interstitial cystitis rather than painful bladder syndrome? If a patient initially diagnosed as overactive bladder syndrome is found by MRI to have multiple sclerosis which is responsible for detrusor overactivity, should this patient be regarded as having multiple sclerosis rather than overactive bladder syndrome? If a patient initially diagnosed as having a syndrome suggestive of bladder outlet obstruction is found by prostate biopsy to have prostate cancer, should this patient be counted as having prostate cancer rather than a case of syndrome suggestive of bladder outlet obstruction syndrome? The correct answer to these questions would be ‘Yes’. Syndromes describe functional abnormalities that cannot be explained by routine tests. Once a more precise diagnosis of non-functional disease is found, the patients are to be excluded from having syndromes. Consequently, the following remark is logically valid. ‘When patients with painful bladder syndrome were examined in detail, 40% of them were diagnosed as interstitial cystitis by hydrodistension and biopsy, 10% as bacterial cystitis by meticulous repeated urine cultures, 5% as urethral diverticulum by MRI, 5% as bladder carcinoma by biopsy and 40% as unexplained by any means. By definition, 60% of patients were found to have non-functional and more precisely defined diseases, and 40% patients remaining as unexplained only were genuine painful bladder syndrome.’ Is it not confusing?

A syndrome may have been coined to meet the clinical necessity of describing a patient with definite symptoms but no definite diagnosis, however if ‘no definite diagnosis’ is required for syndromes, whether a patient does or does not belong to a syndrome depends on how meticulously diagnosis work-ups have been done. This is confusable. A syndrome should be defined as a diagnosis name based on symptoms regardless of the causes of the symptoms or the nature of the causes (functional or non-functional). The concept ‘syndrome’ is significant in that it allows a clinical diagnosis of a condition which presents several symptoms without obvious definite diseases. The diagnosis of the syndrome should remain valid, even after a more precise diagnosis is made and/or when the disease is a non-functional one. It is suggested that the requirements for syndromes should be changed in accordance with the underlying concept of syndromes (Table 6).

Table 6.  Current and suggested definitions of symptom syndromes
 Current syndromesSuggested syndromes
Concept/definitionCombination of symptoms but not a precise diagnosisDiagnosis based on symptoms and routine tests
Number of symptomsMust be multipleUsually multiple
Cause of symptomsUnable to identify by routine testsUnable to identify by routine tests
Nature of conditionFunctional abnormalityFunctional or non-functional abnormality
Upon identification of a precise diagnosisThe diagnosis ‘syndrome’ is not usableThe diagnosis ‘syndrome’ is also usable

Confusion on nomenclature

Syndromes are defined by symptoms and are convenient for describing combinations of symptoms. On the other hand the inappropriate naming of syndromes may adversely cause confusion: confusion among painful bladder syndrome and interstitial cystitis, for example.11 Historically interstitial cystitis is a better known name, however the words ‘interstitial’ and ‘cystitis’ have led to a misunderstanding that histology must indicate interstitial inflammation and urinalysis must show pyuria. Thus the Report reasonably suggests the use of ‘painful bladder syndrome’ in preference to ‘interstitial cystitis’, leaving interstitial cystitis as a more specific diagnosis. Ironically, the word ‘painful’ may again lead to a misunderstanding that the patient must have pain as the complaint. The patients of painful bladder syndrome and/or interstitial cystitis are extremely diverse in symptoms (with or without pain), cystoscopic findings (with or without ulcers) and histology (with or without inflammation).23–26 Such an ill-defined condition should not be described by a disease name (interstitial cystitis) but be defined as a syndrome;27 however, painful bladder syndrome may not be the best, since pain syndromes are logically unable to be used for a symptom complex without pain. ‘Overactive bladder syndrome’ is not suitable either, since it requires the sudden compelling desire to void that is not perceived by every interstitial cystitis patient, and does not contain sensations such as pain and discomfort, which are more specific to interstitial cystitis.28 Interstitial cystitis/painful bladder syndrome (IC/PBS), a more comprehensive term, appears to be more sensitive and specific to the condition;24 however, IC/PBS is a chimeric term connecting a disease name (IC) and a syndrome name (PBS) and it is inaccurate as a scientific term, resulting in confusion whether it refers to a disease or to symptoms.

Recent evidence indicates urothelium has sensory function, and its function and dysfunction is implicated in lower urinary tract disorders.29 Up-regulation of the sensory nervous system or sensory hypersensitivity is causative of frequency and urgency and interpreted as one of the mechanisms for OAB symptoms.30 OAB, however, is a symptom syndrome resulting from uncontrolled detrusor overactivity, and it is associated with hyposensitivity rather than hypersensitivity of the bladder.31,32 Hypersensitivity is rather characteristic to painful bladder syndrome as exemplified by over-expression of the transient receptor potential vanilloid receptor.33 The lack of an appropriate syndrome name to describe bladder hypersensitivity (with or without pain) may be increasing confusion.

A suggestion is to define a new syndrome, ‘hypersensitive bladder syndrome (HSB)’, which functions as a counter-concept of ‘overactive bladder syndrome (OAB)’. Both syndromes are parts of a more inclusive syndrome, ‘frequency/urgency syndrome’. Urgency in this context means the strong urge to void or the pressing need to void, a broader and more common sense1 than that defined by the Report. Urgency in OAB is characterized by sudden onset and/or fear of leakage, while urgency in HSB is of a persistent nature and associated with the fear of pain. Overactive bladder syndrome with leakage (OAB wet) is the typical overactive bladder syndrome. Painful bladder syndrome is the typical hypersensitive bladder syndrome. Interstitial cystitis is a representative disease causing hypersensitive bladder syndrome (Fig. 2).

image

Figure 2. Frequency/urgency syndrome is characterized by frequency (frequent voiding) and urgency (strong desire to void). It is an inclusive term including overactive bladder syndrome (OAB), hypersensitive bladder syndrome (HSB), and other conditions that is associated with frequency and urgency. Urgency in OAB is characterized by sudden onset and/or fear of leakage, while urgency in HSB is of a persistent nature and is associated with the fear of pain. OAB wet is a subgroup meaning OAB with leakage. Likewise painful bladder syndrome (PBS) is a subgroup of HSB with pain. Interstitial cystitis (IC) is one of the diseases presenting frequency/urgency syndrome, predominantly overlapping HSB and PBS.

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Confusion on sequence

The Report describes pain syndromes first and then symptom syndromes. Since this Report is relevant to LUTS, symptom syndromes should come first, and pain syndromes should be treated as particular types of symptom syndromes that feature pain as the central symptom.

Measuring the frequency, severity and impact of lower urinary tract symptoms

  1. Top of page
  2. Abstract
  3. Introduction
  4. Lower urinary tract symptoms (LUTS)
  5. Frequency
  6. Urgency
  7. Urinary incontinence
  8. Bladder sensation
  9. Voiding symptoms
  10. Post micturition symptoms
  11. Pain
  12. Syndromes
  13. Measuring the frequency, severity and impact of lower urinary tract symptoms
  14. Physical examination
  15. Conditions
  16. Discussion
  17. Conclusions
  18. References

Definition

The Report describes three forms of recording micturition events: the micturition time chart, the frequency volume chart, and the bladder diary. The most important information derived from the recording is the frequency and the voided volume. The frequency is daytime frequency (voids during waking hours), nocturia (voids during a night's sleep) or 24-h frequency (total voids during a specific 24-h period). By calculating the volume voided, 24-h urine production, polyuria, nocturnal urine volume, and nocturnal polyuria are determined. Polyuria is defined as the 24-h production over 2.8 L in adults. This cut-off level was adopted from the 24-h production of a person with a body weight of 70 kg producing over 40 mL/kg/day (70 kg*40 mL/24 h = 2.8 L). Nocturnal urine volume is the total urine volume voided from the time of going to bed with the intention of sleeping until the time of waking or rising. It excludes the last void at night and includes the first void in the morning. Nocturnal polyuria is defined as the increased proportion of the 24-h production at night. The cut-off of ‘increased’ depends on age: ‘over 20%’ in young adults and ‘over 33%’ in adults over 65 years of age. Maximum voided volume is defined as the largest volume of urine voided during a single micturition.

Confusion

A concern pertains to the terms ‘daytime frequency’, ‘nocturia’ and ‘24-h frequency.’ Confusion between ‘nocturia’ as the symptom (a complaint of waking at night to void) and ‘nocturia’ as frequency (voids during a night's sleep) may arise. ‘Night-time frequency’ would allow easier understanding by contrast with daytime frequency. For 24-h frequency, the last voiding usually does not take place exactly 24 h after the first. Assume a case where recording is started at 7:00 am, and the 10th voiding takes place at 5:00 am on the following day. If the next voiding takes place at 9:00 pm, should we regard the 24-h frequency as 10 or 11 or 10.5? For voided volume, should we assign half of the volume voided at 9:00 am to the volume for the previous day when calculating the 24-h urine production? If such strict calculation is not required, a more approximate expression such as ‘1-day frequency’ may be linguistically more appropriate.

Variables regarding urine volume are confusing. Two terms, ‘out-put of urine’ and ‘production of urine’, are used to refer to urine volume. Since patients measure only the out-put of urine in diary recordings, the out-put of urine should be used throughout. Polyuria cut-off (24-h production over 2.8 L) presumes the average body weight of 70 kg. This is not well-balanced as an international standard and is scientifically ungrounded. The definitions of polyuria and nocturnal polyuria lack consistency; an absolute value (2.8 L) is used for polyuria while a relative value is used for nocturnal polyuria, which should be called ‘relative nocturnal polyuria.’ Furthermore nocturnal polyuria has two definitions by age: over 20% in young adults and over 33% in adults of age 65 and higher, with no clear definition of ‘young.’ Defining over- or under-production of urine on the basis of urine volume per body weight would be physiologically common and valid.6,34–36 The criterion for the single voided volume should also be defined on a body weight basis35 (Table 7).

Table 7.  Confusion and Suggestion for frequency volume chart variables
TermConfusion and suggestion
NocturiaConfusion between nocturia and night-time frequency
Should be replaced by increased night-time frequency
24-hLinguistically too strict
One-day is suggested.
PolyuriaIgnoring individual body size
One-day urine production over 40 mL/kg is suggested.
Nocturnal polyuriaExpressed in percentage inconsistent with polyuria in absolute value
A criterion over XX mL/kg is suggested.
Reduced voided volumeA criterion less than XX mL/kg may be useful.

Physical examination

  1. Top of page
  2. Abstract
  3. Introduction
  4. Lower urinary tract symptoms (LUTS)
  5. Frequency
  6. Urgency
  7. Urinary incontinence
  8. Bladder sensation
  9. Voiding symptoms
  10. Post micturition symptoms
  11. Pain
  12. Syndromes
  13. Measuring the frequency, severity and impact of lower urinary tract symptoms
  14. Physical examination
  15. Conditions
  16. Discussion
  17. Conclusions
  18. References

Definition

The Report provides a description of physical examinations including abdominal, perineal, vaginal, and rectal examinations, and pelvic floor muscle function. Urinary incontinence as a sign is defined as urine leakage seen during examination.

Confusion

The term ‘stress urinary incontinence’ is used for the symptom, sign and disease. It may be better to use a term such as ‘urinary incontinence on stress’ as a sign to distinguish stress urinary incontinence as a symptom or disease. ‘Urodynamic stress urinary incontinence’ is the term as a urodynamic finding.

Conditions

  1. Top of page
  2. Abstract
  3. Introduction
  4. Lower urinary tract symptoms (LUTS)
  5. Frequency
  6. Urgency
  7. Urinary incontinence
  8. Bladder sensation
  9. Voiding symptoms
  10. Post micturition symptoms
  11. Pain
  12. Syndromes
  13. Measuring the frequency, severity and impact of lower urinary tract symptoms
  14. Physical examination
  15. Conditions
  16. Discussion
  17. Conclusions
  18. References

Definition

The Report describes some pathological conditions that are not mentioned elsewhere. Retention of urine is divided into acute and chronic types. Acute retention is a painful, palpable or percussible bladder, when the patient is unable to pass any urine. It may be difficult to detect a painful, palpable or percussible bladder in some patients. Chronic retention is a non-painful bladder, which remains palpable or percussible after the patient has passed urine. Such patients may be incontinent. Related to the incontinence, ‘incontinence associated with chronic retention of urine (overflow incontinence)’ is no longer recommended, because the term is considered confusing and lacking convincing definition. Regarding prostatic conditions, the Report defines ‘benign prostatic obstruction’ as a form of bladder outlet obstruction, benign prostatic hyperplasia (BPH) as a term used for histological pattern (not a disease), and ‘benign prostatic enlargement’ as the enlarged prostate in the absence of histology.

Confusion

The recommendation not to use ‘overflow urinary incontinence’ is confusing or even perplexing. This type of urinary incontinence occurs in patients with chronic urinary retention when urine accumulates in the bladder until the intravesical pressure exceeds the urethral closure pressure. It is a convenient term to express the complicated condition and clinically useful to warn clinicians (especially, non-urologists) not to overlook it due to peculiarity of terminology37–39 (Table 3).

Terms related to non-malignant prostate abnormality are also confusing. To which syndrome, condition, or disease should the patient diagnosed as having BPH so far be classified? Is it ‘lower urinary tract symptoms suggestive of bladder outlet obstruction’ while obstruction is unproven, and then ‘benign prostatic obstruction’ after it is proven? Obstruction is not the sole pathology responsible for the symptoms of men with an enlarged prostate; urethral hypersensitivity may play a significant role in symptoms of these men.40 In Japanese, this syndrome/condition/disease is called ‘Zenritsusen-hidai-sho’. ‘Zenritsusen-hidai’ is literally prostatic hypertrophy, and the suffix ‘sho’ means disease. Thus it means ‘prostatic hypertrophy disease’, not simply referring to histology. In English BPH has been used as a disease name. Although it can be mistaken for histology, is there so much confusion at clinical or research settings among BPH as histology and BPH as a disease? It is suggested that BPH should be reserved as a disease name whilst noting that BPH can have two meanings.

Discussion

  1. Top of page
  2. Abstract
  3. Introduction
  4. Lower urinary tract symptoms (LUTS)
  5. Frequency
  6. Urgency
  7. Urinary incontinence
  8. Bladder sensation
  9. Voiding symptoms
  10. Post micturition symptoms
  11. Pain
  12. Syndromes
  13. Measuring the frequency, severity and impact of lower urinary tract symptoms
  14. Physical examination
  15. Conditions
  16. Discussion
  17. Conclusions
  18. References

The latest Report from the ICS standardization subcommittee is an enormous achievement by the society2 and may be one of the most frequently cited articles by recent papers or brochures in this field. It has standardized terminology on lower urinary tract symptoms (LUTS), signs suggestive of lower urinary tract dysfunction, urodynamic observations and conditions, and treatment. Of these, the section on LUTS was most extensively revised by describing the current terms in more detail, changing the meaning of them, developing proper terms for new concepts, and classifying them accordingly, however now that the new terminology is more widely spread, confusion and concerns are heard from the users. The present review has summarized confusion section by section, and suggested possible solutions to this confusion.

In reviewing the definition and confusion of the terminology, several common reasons for confusion are appreciated (Table 8). First, as the Report mentions at the beginning, ‘LUTS are qualified as those reported by the individual’, the symptoms should be based on the patient's complaints. In addition, terminology for LUTS is used not only by specialists and researchers but also by non-specialists and importantly by patients, who are lay people where medical terminology is concerned. Marked discrepancy from the common usage naturally causes confusion. Secondly, any change of meaning (definition), subtle or profound, may result in confusion. This is because a word has its own life and will never be taken in a different sense overnight. Words that have been used for many years should not be changed without obvious advantages for change or unavoidable inconvenience caused by the current forms. Thirdly, the terms with strict and/or excessive qualifiers narrow the meaning of the word and/or allow arbitrary interpretation and can cause confusion. A concise and neutral statement is preferred for definition to avoid confusion or ambiguity. Technically, the terms with paired concept but not paired in wording or definition may be confusing. Use of the same term for different meanings or use of too long a term is also confusing and/or inconvenient.

Table 8.  Reasons for confusion in terminology
Reasons for confusionExamples
Discrepancy from common usageNocturia
Urinary incontinence
Urgency
Bladder sensation
Pain
Change of definitionUrgency
Urinary incontinence
Too strict definitionUrgency
Syndromes
Painful bladder syndrome
Lack of consistencyIncreased daytime frequency and nocturia
Polyuria and nocturnal polyuria
One term for different meaningsNocturia
Stress urinary incontinence
Too longLower urinary tract symptoms suggestive of bladder outlet obstruction
Ignored or overlookedSome types of incontinence
Straining
Hypersensitive bladder syndrome
Doubtful validity in cut-offsPolyuria
Nocturnal polyuria

It would be advisable that revision of terminology should be undertaken conservatively, especially with great caution regarding changing the definition.41 When one has to describe a new concept, coining a new term rather than changing the current term would be less likely to incur confusion. Lastly the scope of terminology or cut-off levels for specific conditions should be validated by scientific evidence.

Conclusions

  1. Top of page
  2. Abstract
  3. Introduction
  4. Lower urinary tract symptoms (LUTS)
  5. Frequency
  6. Urgency
  7. Urinary incontinence
  8. Bladder sensation
  9. Voiding symptoms
  10. Post micturition symptoms
  11. Pain
  12. Syndromes
  13. Measuring the frequency, severity and impact of lower urinary tract symptoms
  14. Physical examination
  15. Conditions
  16. Discussion
  17. Conclusions
  18. References

The International Continence Society has extensively examined terminology related to lower urinary tract function. The recent version has provided a virtually new terminology for lower urinary tract symptoms through the revision of the existing terms and the introduction of new terms, yet there is still confusion and ambiguity among clinicians and researchers. This review sheds light on the confusion to make it more readily appreciated. The terminology should be continuously challenged for scientific validity to develop a more accurate, refined and user-friendly vocabulary of words.

References

  1. Top of page
  2. Abstract
  3. Introduction
  4. Lower urinary tract symptoms (LUTS)
  5. Frequency
  6. Urgency
  7. Urinary incontinence
  8. Bladder sensation
  9. Voiding symptoms
  10. Post micturition symptoms
  11. Pain
  12. Syndromes
  13. Measuring the frequency, severity and impact of lower urinary tract symptoms
  14. Physical examination
  15. Conditions
  16. Discussion
  17. Conclusions
  18. References