A 19 yr old, male, smoking, University student travelled overland from Cape Town to northern Namibia, through the Caprivi Strip to Victoria Falls and Lake Kariba, on through Zambia to Lake Malawi where he swam in Cape Maclear, Monkey bay and Kata bay, before continuing on to Dar es Salaam, Lake Tanganika and Gombe National Park to see the Chimpanzees. He returned to Cape Town via the Quirimbas archipelago and Musina da Praia in Mozambique. During his travels, which lasted 5 months, he and his girlfriend camped most of the time and occasionally, stayed in small guesthouses. They ate food from the roadside and took doxycycline chemoprophylaxis, although his adherence was poor (once every 3 days). He received multiple mosquito bites, but was unaware of any Tsetse fly bites or other insect exposures. Pre-travel vaccinations included Yellow Fever alone.
Two weeks after experiencing itching skin following a swim in Cape Maclear, he awoke with fever and chills associated with profuse watery diarrhoea 5-6 x /day and severe colic. Blood tests for malaria were negative, but he took Co-artem, under-dosing himself by half for the last 3 doses. Symptoms continued, but the diarrhoea resolved after 4 days, leaving him lethargic, febrile and and with a developing dry cough. Stool, blood and urine tests were negative. He was given a course of double-dose doxycycline, ciprofloxacin and azithromycin resulting in resolution of fever, but not the cough, which persisted and became productive of white sputum after 10 days. Sputum production cessed when he stopped smoking. 3 weeks after his first fever, he experienced headache, meningism, fever and worsening of his cough. He was diagnosed with typhoid fever on clinical grounds alone, receiving a 10 day course of ciprofloxacin and another course of Co-artem for good measure. Thereafter, there was a slow resolution of symptoms, although he was left with lethargy and a dry cough. He returned to Cape Town to seek medical advice.
At the time of presentation, his cough had resolved and he had started smoking and drinking again. Examination was non-contributory. He was afebrile, his chest was clear with no organomegaly.
Investigation revealed a total WBC 10.4 x 109/L, but eosinophils were raised at 2.20 x 109/L [normal 0.00-0.40]. The rest of his FBC was normal as was hepatic and renal function. CRP 11.6 mg/L. Chest X-ray was normal.
A clinical diagnosis of resolving acute schistosomiasis was made. Three filtered urine and 3 concentrated stool specimens were negative for schistosoma ova, but schistosoma IgG ELISA was positive, as was the IgM and IgA responses to cercarial antigens.
As his symptoms had resolved, he was given praziquantel 40mg/kg in 2 divided doses. Within hours of his second dose, his cough and fever returned with profound malaise. He was given prednisone 0.5mg/kg with an excellent symptomatic response within the 4 hours of the first dose. He was treated for 3 days in total with no relapse.
Question 1: How is the immunopathogenesis of schistosomiasis linked to the clinical presentation of disease and how does it impact on choice of treatment for acute schistosomiasis?Continue to Answer 1