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Keywords:

  • behavioural disorders;
  • diagnosis;
  • DSM V;
  • ethics;
  • level of diagnosis

Introduction

  1. Top of page
  2. Introduction
  3. A Brief Primer on Diagnosis
  4. The Diagnosis and Treatment of Behavioural Disorders
  5. References

Your editorial[1] on disease mongering raised a real and important issue. In the rural area where I work, most of the children I see have behavioural and/or school problems. These problems are real, often severe enough to disrupt families and classes. Help is needed, but hard to get. However, if the child is diagnosed with an autistic-type disorder, there is financial aid for the parents and school, and also paid sessions with paramedical professionals. Only medical specialists can certify this diagnosis, so they are under pressure to do so. If our diagnoses were based on objective evidence, this would be no problem, but the official Diagnostic and Statistical Manual of Mental Disorders (DSM) criteria use subjective symptoms. We see some of these symptoms in our rooms, but children in strange surroundings seldom show their full range of customary behaviour. We do not have trained staff to observe these children in different situations; we must get extra information from carers and teachers. We ask whether certain symptoms are outside the normal range, but the answer depends on the observer's standards of normal and the surroundings at the time. Knowing the benefits gained from positive diagnosis must also influence their answers. Agreement between such observers is poor,[2] but so long as the observations of one or more observer meet the DSM criteria, we have a formal diagnosis. The imprecision of our diagnoses makes these pressures hard to resist. Most behavioural disorders are newcomers to medicine. Many professionals rightly question the diagnostic criteria, their validity and even their existence. A review of their provenance would help clear this uncertainty.

A Brief Primer on Diagnosis

  1. Top of page
  2. Introduction
  3. A Brief Primer on Diagnosis
  4. The Diagnosis and Treatment of Behavioural Disorders
  5. References

In the simplest analysis, medical diagnoses can be made at three levels.

The syndrome is the lowest and simplest level of diagnosis. This is a collection of clinical symptoms and signs that form a recognisable and clinically useful pattern. It needs no other data input and no understanding of the underlying of pathology or causes. It was the norm before the development of ‘scientific’ medicine. Many of today's standard diagnoses started as syndromes, such as nephrotic syndrome and Down syndrome. We retain the name but now have deeper knowledge of these conditions. However, we know much less about behavioural disorders; in spite of intensive research, most are still just syndromes.

The pathological diagnosis is the next level, both historically and intellectually. This needs information that cannot be gained from clinical practice, but from relating post-mortem findings to the clinical features. This has been further developed through histology and more recently from imaging studies. We also know the biochemical pathology of many diseases. This knowledge lets us deduce pathological changes from clinical signs and symptoms, reinforced by biopsy, biochemistry or imaging if necessary. We can also treat the lesion rather than the symptom with surgery, drugs or other methods.

The aetiological diagnosis is a still higher level. The primary source of aetiological data was microbiology, so germs could be related with pathology and thence to clinical features. It also gave a logical basis for antibiotics and similar drugs. In public health, aetiology has gone further with statistical testing showing more remote causes for chronic disease. Statistical studies have demonstrated that abnormal genes lead to clinical disorders, but until we understand the pathological pathways, we cannot use this knowledge for management of cases.

We can use these additions to clinical medicine in two ways. From our knowledge of underlying processes, we can use selective items of clinical history and examination to pinpoint the causative pathology and aetiology. Once we have narrowed the field, we can use investigations to confirm and clarify the final diagnosis.

The Diagnosis and Treatment of Behavioural Disorders

  1. Top of page
  2. Introduction
  3. A Brief Primer on Diagnosis
  4. The Diagnosis and Treatment of Behavioural Disorders
  5. References

Western medicine has taken 200 years and has passed through several stages to reach its present level of knowledge, sophistication and management in physical disease. Behavioural medicine started much later and seems to be passing through the same stages, although hopefully more quickly.

The DSM IV and DSM V seek to establish syndrome-based diagnoses. They are collections of symptoms and signs that determine whether a diagnosis is present. This process depends on the reliability of the reported symptoms and signs. Different observers give widely divergent reports on the symptoms and signs of the same child, often leading to different DSM diagnoses. The DSM features tell us nothing about their underlying causes. To complicate matters, some DSM IV diagnoses, such as the autistic group, have been amalgamated in DSM V, while other DSM IV diagnoses have been subdivided, although the database is largely unchanged. One must query the validity of the disease definitions – they are a work in progress. This is still appropriate for autistic type disorders where there is much knowledge, and more is accumulating, but available knowledge does not yet form a coherent picture of pathology and aetiology that we can use clinically for diagnosis and management. We hope for a breakthrough, but until then, syndrome diagnoses are the best we can do. This also means that our treatment must be symptomatic rather than treating the underlying causes. Behavioural therapists claim that they are treating at a deeper level; these claims are largely unproven. In the meantime, it would be best to change the name of autistic spectrum disorder to autistic spectrum syndrome as this would acknowledge that it is a collection of symptoms with the likelihood of many underlying causes, pathologies and outcomes.

We know more about attention deficit disorder and attention deficit hyperactivity disorder (ADHD), but the DSM IV diagnoses (they are merged in DSM V) are still symptom based so they would be better described as syndromes with varying aetiologies and outcomes and also probably different pathologies. However, many of these children seem to have a defect in dopamine metabolism in the subcortical nuclei, so we have a possible way of treating the lesion as well as the symptoms. This defect is strongly inherited and is almost always present in children with fetal alcohol damage, but there are many children with the clinical syndrome but lack these background features. Family history and observation will help identify those with the underlying biochemical disorder, but there is presently no objective diagnostic tool available. However, we can use a therapeutic challenge. In the early days of the coeliac disease diagnosis, before we had biopsy and biochemical markers, we would withdraw gluten from the diet, if the symptoms improved, we would then challenge with gluten. If the symptoms recurred, then we could make a working diagnosis of coeliac disease. We can use a stimulant such as methylphenidate (Ritalin) in a similar way for diagnosing ADHD. The biochemical action of stimulants is known. Most children with dopamine-related ADHD respond very well to Ritalin. We work up to an adequate dose of Ritalin; if the symptoms of ADHD improve dramatically both at home and at school, but return again when the Ritalin is stopped, then we can make a working diagnosis of ADHD. As with coeliac disease, this should be a temporary measure until we have more specific biochemical or imaging methods of diagnosis.

The present status of behavioural disorders is both frustrating and exciting. These are real problems, but with our present knowledge, it is hard to distinguish the causes, and therefore give an objective diagnosis and effective treatment. We are under pressure from parents and teachers so that they can get government funding that will help the child. It is exciting because this is the cutting edge of medicine; we can hope that within a few years, our present uncertainties will be history and we can make pathological or pathophysiological diagnoses with known aetiology and pathology so we treat these children rationally and effectively. In the meantime, when the DSM symptoms indicate a diagnosis of a behavioural syndrome, we do not have the objective pathological and aetiological knowledge to deny a request for a diagnosis. The pressures are all in one direction, disease mongering prospers.

References

  1. Top of page
  2. Introduction
  3. A Brief Primer on Diagnosis
  4. The Diagnosis and Treatment of Behavioural Disorders
  5. References