Acute Schistosomiasis in Travelers: 14 Years' Experience at the Hospital for Tropical Diseases, London

Abstract

Abstract. We report 79 cases of acute schistosomiasis. Most of these cases were young, male travelers who acquired their infection in Lake Malawi. Twelve had a normal eosinophil count at presentation and 11 had negative serology, although two had neither eosinophilia nor positive serology when first seen. Acute schistosomiasis should be considered in any febrile traveler with a history of fresh water exposure in an endemic area once malaria has been excluded. Acute schistosomiasis was first described in 1847 in the prefecture of Katayama, Hiroshima district, Japan.1 Women brought to the region to be married were found to become acutely unwell with a fever after they had been exposed to fresh water. Acute schistosomiasis, or Katayama fever, is classically seen among travelers to regions where the disease is endemic. It is thought to be an immune-complex phenomenon, precipitated by the onset of egg-laying by newly matured adult female schistosomes. This occurs between 2 and 12 weeks after exposure 2 ; the syndrome is seen almost exclusively among people who have no history of previous exposure to the infection. The symptoms of Katayama may include fever, cough, an urticarial rash, and diarrhea, with an elevated eosinophil count as a characteristic laboratory finding 2 ; not every individual will have all of these. We report the clinical and laboratory features of acute schistosomiasis among 79 travelers who presented to the Hospital for Tropical Diseases (HTD) in London between 1998 and 2012.Acute schistosomiasis is often a clinical diagnosis at the time of presentation and may only be confirmed later in the illness once a serological test has had time to become positive. We therefore defined cases according to the following five predefined criteria, with each case fulfilling all five.1. Presence of at least one: fever, cough, rash, diarrhea. 2. A recent history of fresh water exposure in an area where schistosomiasis is endemic. 3. Positive schistosomal serology, either at presentation or follow-up. 4. Raised eosinophil count at some point during the illness. 5. Symptoms not attributable to any other condition.Cases were identified from three sources: a database of schistosomiasis cases and two prospective databases of both inpatients and outpatients seen at HTD. Clinical notes and laboratory data were reviewed using a standard proforma.Time from exposure to symptoms was taken as the first date of potential exposure to the date of symptom onset. Laboratory results were obtained from the appropriate clinical laboratories in University College London Hospitals. The schistosomal serology is an "in-house" enzyme-linked immunosorbent assay (ELISA) detecting antibody to Schistosoma mansoni soluble egg antigen; once positive this test may remain so for years despite successful treatment. Positive results are reported as levels (bands of optical density from 1 to 9) with a result of one or more regarded as positive. 3 The serology test has a sensitivity of 96% for S. mansoni and 92% for Schistosoma haematobium, whereas t...

Schistosomiasis in Malawi: a systematic review

“…Most articles by foreign-based authors confirmed the existence of a risk of contracting schistosomiasis if exposed to Malawian water bodies, particularly Lake Malawi. This aspect has been discerned from published case studies involving some of the visitors who had been to Malawi and later developed symptoms of contracting the disease [25,28,30,33,35,36,[38][39][40]46,51,55,81,91]. Furthermore, we observed that research on schistosomiasis has not been evenly distributed geographically across the country.…”

“…Of the 89 reviewed documents, 22 (25%) reported on individuals who had developed signs and symptoms of schistosomiasis after returning from a visit to Malawi. These documents comprised 13 case reports and 9 letters to the editor written by non-Malawian authors [25,30,[33][34][35][36][37][38][39][40][46][47][48][49][50][51][52][53][54][55][56][89][90][91]94,95,97,107].…”

Schistosomiasis in Malawi: a systematic review

“…This finding may be explained by the observation that urinary schistosomiasis is more common and widely distributed in Malawi and thus comprises a larger public health problem than intestinal schistosomiasis [ 20 ],[ 23 ],[ 26 ],[ 31 ],[ 103 ]. It may also be explained by the observation that urinary schistosomiasis is common in the major tourist destinations around Lake Malawi and thus receives substantial international attention [ 25 ],[ 28 ],[ 30 ],[ 36 ],[ 39 ],[ 45 ],[ 46 ],[ 55 ],[ 91 ],[ 97 ]; this may further explain the observation that the human aspects of urinary schistosomiasis receive more attention than other aspects of the infection [ 110 ]. For urinary schistosomiasis, more than two thirds of the reviewed documents covered aspects of the definitive human host, whereas less than a quarter of the documents addressed the intermediate host and none addressed the parasite itself.…”

“…Of the 89 reviewed documents, 22 (25%) reported on individuals who had developed signs and symptoms of schistosomiasis after returning from a visit to Malawi. These documents comprised 13 case reports and 9 letters to the editor written by non-Malawian authors [ 25 ],[ 30 ],[ 33 ]-[ 40 ],[ 46 ]-[ 56 ],[ 89 ]-[ 91 ],[ 94 ],[ 95 ],[ 97 ],[ 107 ].…”

Subcutaneous nodule on the scrotum

“…Due to increasing travel to far-off destinations, including tropical regions, schistosomiasis is an increasingly important, albeit rare, differential diagnosis for dermatologists to recall when diagnosing unusual "souvenirs" [8]. As our experience…”