A High Index of Malaria Suspicion is Necessary for Febrile Episodes in Travellers and Migrants Coming from Endemic Areas
Abstract Objectives: We aimed to analyse the likelihood of imported malaria in people with a suggestive clinical picture and its distinctive characteristics in a hospital in the south of Madrid, Spain.Methods: This retrospective study consisted of a review of all medical files of patients with any malaria test registered at Móstoles University Hospital between April 2013 and April 2018. All suspected malaria cases were confirmed by Plasmodium spp. polymerase chain reaction (PCR).Results: Of the 328 patients with suspected malaria (53.7% migrant-travellers; 38.7% visitors; 7.6% travellers), 108 cases were confirmed (101 by P. falciparum), accounting for a 33% positive sample rate. Sixteen cases were diagnosed only by PCR. Patients with malaria, compared to those without, presented predominantly with fever (84% vs 65%), were older (34 vs 24 years), sought medical attention earlier (17d vs 32d), had a greater number of previous malaria episodes (74% vs 60%), lower levels of platelets (110,500µL vs 250,000µL), and higher of bilirubin (0.6mg/dL vs 0.5mg/dL). Severe malaria was present in 13 cases; no deaths were recorded. Malaria diagnosis showed a bimodal distribution with two peaks: June to September and November to January. Conclusion: Malaria is still a common diagnosis among febrile patients coming from the tropics specially among migrant travellers. Fever, thrombocytopenia, and/or high bilirubin levels should raise suspicion for this parasitosis. Prompt diagnosis is crucial to avoid severe cases and deaths. We suggest a proportion around 30% of positive samples as a potential adequate index of suspicion for malaria diagnosis.