Abstract
Malaria is distribited in many tropical and subtropical regions, but the risk is highest in sub-Saharan Africa. If untreated, infection with P. falciparum is a fatal in non-immune travellers.
This fact is often neglected, and there are increasing numbers of tourists as well as Czech workers who travel to high-risk areas without receiving appropriate antimalarial prophylaxis and sufficient information on the severity, clinical manifestations, diagnosis, and treatment of malaria. Infection with P. falciparum may manifest in more than one month after returning from a risk area, and P. vivax and P. ovale relapses occurring in months or even years.
In the case of a febrile disease during a stay in or upon return from a malaria region, the infection has to be ruled out by examining stained blood smears (thick and think blood smear). Treatment must be initiated immediately after diagnosis and is typically provided at infectious diseases departments, a list of which is available at www.infekce.cz.
The combination of artemether and lumefantrine or that of atovaquone and proguanil is the drug of choice in uncomplicated P. falciparum infection, with mefloquine or quinine being used only when the above are unavailable. Chloroquine can only be used in non-falciparum infections, and anti-relapse therapy with primaquine is indicated in tertian vivax and ovale malaria.
Malaria prophylaxis is based on preventing mosquito bites (exposure prophylaxis) and a preventive use of antimalarial drugs (antimalarial chemoprophylaxis) when there is a high risk of malaria. In the Czech Republic, atovaquone/proguanil (Malarone) and doxycycline are available for prophylaxis.
The pathogenesis of tropical malaria is a comprehensive set of processes caused by a production of parasitic antigens and accumulation of P. falciparum - infected and uninfected red blood cells in many organs. The clinical condition may result in impaired microcirculation, organ hypoperfusion, tissue hypoxia, and shock with multiple organ failure.
Cerebral malaria is the most serious complication that is manifested by a severe disturbance of consciousness (sopor, coma). The following are thought to be implicated in the pathogenesis of cerebral malaria: an effect of sequestration of infected red blood cells and obstruction of microcirculatory or a local production of nitric oxide that can act as a false neurotransmitter, and thus induce encephalopathy.
IV artesunate is the drug of choice in treating cerebral malaria; however, if unavailable in the Czech Republic, IV quinine in combination with IV clindamycin or doxycycline is used. Supportive treatment of cerebral malaria and other complications in multiple organ failure involves the use of all available and recommended modalities, similarly to other urgent conditions.