Imported malaria: Successful treatment of 31 patients in the era of chloroquine resistance

The diagnosis and management of imported malaria presents a continuing chal lenge in developed countries, including Taiwan. We retrospectively analyzed the records of all 31 patients with imported malaria treated at National T aiwan University Hospital From January 1984 through December 1998. Plasmodi um falciparum was identified as the causative malarial parasite in 18 patie nts, P. vivax in 12, and P. ovale in one. All 31 patients had fever, but on ly 13 presented with the characteristic fever pattern. The most common init ial laboratory abnormalities were thrombocytopenia (20/31), mild hyperbilir ubinemia (20/31), and leukopenia (7/31). The median time from the onset of fever to the correct diagnosis was 4 days for P. falciparum and 5 days for P. vivax. In 28 cases, the clue that led to early diagnosis was the patient 's travel history. Quinine, but not chloroquine, was effective in 17 out of 18 cases of falciparum malaria. Three patients treated with intravenous qu inine required a change of regimen because of life-threatening quinine toxi city; artesunate served as a safe and effective alternative in this situati on. While most patients with tertian malaria were cured with the standard c hloroquine and primaquine regimen, a higher dosage was required for one cas e acquired in Papua New Guinea. All patients, including two with severe mal aria, survived. We conclude that, the mortality of imported malaria in the chloroquine resistance era can be minimized with early recognition by obtai ning a thorough travel history, and instituting appropriate antimalarial ch emotherapy based on precise identification of species. Quinine toxicity sho uld be closely monitored, especially when this drug is given intravenously.