A case of cerebral malaria presenting to a District General Hospital
Malaria is the commonest cause of imported infection in non-endemic areas, with 6749 cases reported within the European Union in 2010. (0.9 per 100,000).1 80% of these were in the France, UK, Germany and Italy, with the majority being acquired in sub Saharan Africa.2 In the UK, the median age of cases is 31. Anti malarial chemoprophylaxis is extremely effective, when taken properly, although studies repeatedly demonstrate that the majority of travellers do not do this.
Malaria is caused by infection with the protozoan parasite Plasmodium. Severe disease nearly always caused by the Falciparum species. It is transmitted by the female Anopheles mosquito. The life cycle of the Plasmodium parasite is shown in figure 1.
The incubation period is 12-14 days. After inoculation the infected sporozoites are taken up within the liver, where they form schizonts at around day 10. These rupture to release merozoites into the bloodstream, which in turn invade red blood cells, forming trophozoites. These become schizonts over 24-72 hours. When these rupture to release more merozoites, the cycle continues as well as haemolysis occurring.3 Gametocytes are formed at a later stage, and these are taken up by the mosquitoes, leading to the spread of infection to others.
The end organ damage in malaria is caused by sequestration of red blood cells in capillaries, and subsequent occlusion and microvascular obstruction, leading to hypoperfusion.
A 41 year old gentleman presented to our Emergency Department, 12 days after returning from a working trip to sub-Saharan Africa. He had been staying with friends, and had described feeling unwell for a few days with viral symptoms, followed by a sudden deterioration in his conscious level, and Jaundice. On admission to hospital, his GCS was E4M4V1; He was biochemically jaundiced, with thrombocytopenia, and an Acute Kidney Injury. Rapid malaria testing demonstrated Plasmodium Falciparum and Ovale species, and parasite load was 6% on subsequent blood film. He was treated with IV Artesunate, and required supportive care, including intubation, when his GCS dropped to 7. He never required renal replacement therapy. He was transferred to the regional Infectious diseases unit, where he remained on Intensive care for 3 days, before he was well enough to be moved to a ward. He was subsequently discharged home 11 days after presentation, having made a full neurological recovery.