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Abstract

  1. Top of page
  2. Abstract
  3. Case Reports
  4. Discussion
  5. Declaration of Interests
  6. References

Schistosoma haematobium infection is mainly associated with urinary schistosomiasis. Here, we describe two cases of S haematobium infection in workers returning to China from Tanzania and Angola. They had hematuria and were misdiagnosed as having tuberculosis or tumor of the bladder. The diagnosis was established by discovery of eggs in the urine.

Schistosoma haematobium is an important zoonotic parasite associated mainly with urinary schistosomiasis. Infection in humans occurs by skin contact with cercaria-contaminated freshwater during swimming, fishing, and bathing. The cercariae burrow into the skin and enter the blood stream of the host where they migrate to the sinusoids of liver to mature into adults. Then, they migrate from that organ and reach the vesical, prostatic, and uterine plexuses by way of the hemorrhoidal veins. Eggs deposited by them in the wall of the urinary bladder and other organs may cause a granulomatous response in the host. The main clinical manifestations of S haematobium infection are hematuria, urinal tract blockages, and fibrosis of the bladder.[1]

Schistosoma haematobium infection is endemic to 53 countries and is confined to Africa, the Middle East, India, and Portugal. With economic globalization and rapid development of tourism, the movement of population has become increasingly frequent, which has made possible the spread of this infection to nonendemic countries. In England, France, Italy, Germany, Israel, Denmark, and the Netherlands, imported schistosomiasis haematobium has been happening for decades.[2-5] However, it is a relatively recent phenomenon in China and other Asian countries.[6] In Africa, it is estimated that there are about 1 million Chinese workers employed mainly in building, water supplying, oil exploiting, and road paving.[7, 8] But, the knowledge of African diseases is lacking among Chinese workers, as well their physicians. As a result, when they are exposed in Africa and present clinical manifestations after returning to China, they are often misdiagnosed. From 2005 to 2009, 17 imported falciparum malaria cases (with one death) in workers returning to Henan Province of China from Africa were misdiagnosed for more than 1 week.[9] In this article, we report two imported cases of S haematobium infection in workers returning to China from Tanzania and Angola.

Case Reports

  1. Top of page
  2. Abstract
  3. Case Reports
  4. Discussion
  5. Declaration of Interests
  6. References

Case 1

On March 21, 2010, a 29-year-old man from Luoyang city of Henan Province in central China presented to a local clinic with a 3-week history of intermittent terminal bloody urine. He had been working in Rukwa region of Tanzania from April 2009 to March 2010 where he often went to swim and bathe in Mpanda River and Tanganyika Lake. The hematuria started 2 weeks before his return from Tanzania. He was treated for suspected cystitis, which did not improve, and was admitted to a local hospital. Then, he was suspected to have tuberculosis of the urinary bladder. Despite antituberculosis treatment with pyrazinamide/isoniazid for 4 months, he still had the visible hematuria. On August 3, he was transferred to the urology department for further diagnosis and treatment. Physical examination revealed a healthy male with no abnormal signs on abdominal and genitourinary examination. The results of blood biochemical and hematological tests were normal. Cystoscopy was performed, and erosion and ulceration in the bladder trigone area were observed. Histological sections of the biopsy specimen showed a diffuse granulomatous process with an intense inflammatory infiltrate of mostly plasma lymphocytic cells, eosinophils, and neutrophils. Multinucleated giant cells were also found, but parasite eggs were not seen. Because of the suspected parasitic infection, 24-hour urine sample was collected and examined by sedimentation, which revealed nonglomerular red blood cells and eggs of S haematobium in the urine (Figure 1A). He was treated with praziquantel tablet (40 mg/kg/day in three doses for a single day). Three weeks after treatment, hematuria disappeared and the eggs in the urine were eliminated.

image

Figure 1. (A) Sediment examination of a 24-hour urine sample from case 1 demonstrates the diagnostic terminal spine of egg of Schistosoma haematobium (original magnification, ×400; no stain used). (B) Histopathology of bladder mucosa from case 2 shows the eggs of S haematobium surrounded by intense inflammatory infiltration in granuloma (hematoxylin and eosin stain, ×100).

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Case 2

A 42-year-old man from Yuanyang county of Henan Province worked in Caxito city in Angola from April 2008 to April 2011. During this period, he and his colleagues sometimes went swimming in Kwanza River. He complained of abdominal pain and hematuria 1 month after his return, and was first suspected to have renal calculi at a local clinic. On July 29, 2011, he was admitted to a local central hospital with progressive hematuria. He was diagnosed with tumor of the bladder on the basis of cystoscopy. He underwent open laparotomy for resection of the mass. But, he still had visible hematuria 2 months after the surgery. On October 14, he was transferred to the urology department. Physical examination was unremarkable, as were blood biochemical and hematological tests. The subsequent abdominal ultrasound examination showed bladder wall irregularities and polyps; hydronephrosis of the right kidney and hydroureter were also observed. Eggs of S haematobium were found in the urine. Following this, formalin-fixed, paraffin-embedded tissue sections of the bladder resection specimen were re-examined and many S haematobium eggs were found in the eosinophilic granuloma (Figure 1B). He was treated then with praziquantel (same dosage as in case 1). After 1 month, the laboratory findings indicative of hematuria returned to normal.

Discussion

  1. Top of page
  2. Abstract
  3. Case Reports
  4. Discussion
  5. Declaration of Interests
  6. References

Schistosomiasis caused by Schistosoma japonicum is one of the most serious parasitic diseases and remains endemic to seven provinces of China. The highest prevalence rates (3.8%) were mainly in the lake and marshland regions. It is estimated that there are 726,112 human cases and the number of people at risk in endemic areas was 13,937,235.[10] China is a nonendemic area for S haematobium infection. However, with the increase of the workers and tourists to endemic countries, schistosomiasis haematobium has made its entry as an imported disease.[11] Even a single exposure (eg, from swimming, bathing, paddling, or rafting) can cause infection.[12] At present, thousands of persons only from Henan Province are employed in building, water supply, and irrigation projects in Africa. Additionally, the number of travelers going to Africa has increased along with the increase in income and development of tourism. It is estimated that some of the people returning from Africa might be infected with S haematobium and the infected patients probably remain undiagnosed, because schistosomiasis haematobium is rare in China, and the patients and their physicians are unfamiliar with its clinical manifestations and unaware of the possibility of schistosomiasis. Hence, this imported disease may be neglected, undiagnosed, or misdiagnosed. The delay in diagnosis will put these patients at risk of complications, even development of bladder cancer.[13] The reported two patients received inappropriate treatment for 6 months. Additionally, an American patient with loiasis presented with migratory facial edema 21 years after visiting an endemic area in Africa for only 4 days, and was misdiagnosed as “suspicious for lymphoma” for 2 years.[14] Furthermore, during this period of time, the patients were potentially at risk of contaminating the environment; thus, the parasitic disease imported from Africa might be introduced into China and could spread in the case of presence of appropriate intermediate snail hosts. In the event of this happening, control and elimination of schistosomiasis in China would become more complicated and difficult.

The emergence and misdiagnosis of S haematobium infection is the consequence of poor knowledge of African diseases in China. These two cases indicated the gaps in knowledge and awareness among the general public and authorities of the risk of schistosomiasis from freshwater exposure in Africa. Heath education is the prerequisite of all preventive measures for S haematobium infection. Comprehensive public health education to avoid exposure to contaminated freshwater should be provided to all travelers going to endemic areas. Before workers are sent to Africa, the international labor export companies and public health authorities should adopt a clear policy outlining the risk of schistosomiasis and forbidding exposure to freshwater through swimming, bathing, washing, paddling, and so on. They should also provide appropriate information materials to communicate the risks of exposure to any fresh, untreated water in all the endemic areas of schistosomiasis, specifically targeting the high-risk workers. Besides, the physicians and urologists should be aware of schistosomiasis, and urine microscopy of S haematobium eggs by centrifugation or sedimentation should be carried out as early as possible whenever patients with visible hematuria have a history of working or traveling in endemic countries.[15]

Declaration of Interests

  1. Top of page
  2. Abstract
  3. Case Reports
  4. Discussion
  5. Declaration of Interests
  6. References

The authors state that they have no conflicts of interest.

References

  1. Top of page
  2. Abstract
  3. Case Reports
  4. Discussion
  5. Declaration of Interests
  6. References