Case #042

Fever in someone back from sub-Saharan Africa is malaria until three blood films say otherwise, and nothing else in the history is allowed to distract from that until it is excluded. Prophylaxis abandoned after a week and no bed net removes the only two things that might have protected her. The blood count then points hard in one direction: thrombocytopenia is among the most consistent findings in malaria, and a low platelet count with fever and recent travel is close to a rule of thumb. The anaemia, raised bilirubin and raised LDH are haemolysis, red cells rupturing as parasites complete their cycle, and the palpable spleen is the organ clearing the debris. The rest of the panel exists to remove the conditions that look identical: a negative dengue antigen, sterile cultures, negative typhoid serology and a clean chest film and urine. The film is diagnostic, and it also grades severity, which is what decides the route of treatment. Falciparum shows fine ring forms and readily infects a red cell more than once, and a parasitaemia of 8% is far above the 2% that defines severe disease. She has three more severity markers besides: hypoglycaemia, a lactate above 2, and a creatinine that is climbing. That combination is what makes this intravenous artesunate rather than tablets. Artesunate clears parasites faster than quinine and carries a clear mortality advantage over it, so quinine survives only as a fallback where artesunate is unavailable. It runs until she can reliably swallow, after which a full oral artemisinin-combination course finishes the job, since artesunate alone does not eliminate the infection. Glucose is rechecked repeatedly, because the disease and quinine both cause hypoglycaemia and hers is already 3.4 mmol/L. She also needs warning about delayed post-artesunate haemolysis, which appears one to three weeks later and needs a follow-up blood count.