Imported falciparum malaria in adults: host- and parasite-related factors associated with severity. The French prospective multicenter PALUREA cohort study

Purpose Prospective data on potential factors associated with severity of imported Plasmodium falciparum malaria are lacking. We evaluated whether several host- and parasite-related biomarkers may improve early severity evaluation. Methods Prospective multicenter observational study comparing uncomplicated and severe imported falciparum malaria in adults conducted in France in 52 units, from 2007 to 2010. Association of several host- and parasite-related biomarkers with severity of malaria was tested using univariate and multivariate analyses. Results Of 295 patients, 140 had uncomplicated malaria and 155 severe malaria (including very severe and less severe cases according to predefined criteria). Curative intravenous quinine treatment was used in 154/155 patients with severe malaria and atovaquone/proguanil in 74 % of patients with uncomplicated malaria. Hospital mortality was 5.2 % (8 patients), all in the severe malaria group. Among host-related biomarkers, CRP, procalcitonin, and sTREM-1 were significantly higher and albumin was significantly lower in severe versus uncomplicated malaria; only the last three biomarkers also differed significantly between the very and less severe malaria groups. Among parasite-related biomarkers, only plasma Pf HRP2 was significantly higher in severe versus uncomplicated malaria and in very severe versus less severe malaria; parasitemia did not differ between very and less severe malaria. By multivariate analysis, only lower plasma albumin and higher sTREM-1 were associated with greater severity, with intermediate accuracies. Conclusions During imported malaria, the most useful biomarkers associated with severity seem to be plasma albumin and sTREM-1; and among parasite-related parameters, Pf HRP2 was more strongly associated with severity than parasitemia was.