The online version of this article (doi:10.1186/1475-2875-11-301) contains supplementary material, which is available to authorized users.
The authors declare that they have no competing interests.
MEvW contributed to the data acquisition and analysis and writing of the manuscript. MdeMM, KVJ and JvH participated in the data analysis and revising of the manuscript. RK is responsible for collection of patient materials, patient data and database management. PJvG designed the study, participated in the data acquisition and analysis and in writing and revising the manuscript. All authors have read and approved the final version.
In Plasmodium falciparum infection, peripheral parasite counts do not always correlate well with the sequestered parasite burden. As erythrocytes parasitized with mature trophozoites and schizonts have a high tendency to adhere to the microvascular endothelium, they are often absent in peripheral blood samples. The appearance of schizonts in peripheral blood smears is thought to be a marker of high sequestered parasite burden and severe disease. In the present study, the value of schizontaemia as an early marker for severe disease in non-immune individuals with imported malaria was evaluated.
All patients in the Rotterdam Malaria Cohort diagnosed with P. falciparum malaria between 1 January 1999 and 1 January 2012 were included. Thick and thin blood films were examined for the presence of schizontaemia. The occurrence of WHO defined severe malaria was the primary endpoint. The diagnostic performance of schizontaemia was compared with previously evaluated biomarkers C-reactive protein and lactate.
Schizonts were present on admission in 49 of 401 (12.2%) patients. Patients with schizontaemia were more likely to present with severe malaria, a more complicated course and had longer duration of admission in hospital. Schizontaemia had a specificity of 0.95, a sensitivity of 0.53, a negative predictive value of 0.92 and a positive predictive value of 0.67 for severe malaria. The presence of schizonts was an independent predictor for severe malaria.
Absence of schizonts was found to be a specific marker for exclusion of severe malaria. Presence of schizonts on admission was associated with a high positive predictive value for severe malaria. This may be of help to identify patients who are at risk of a more severe course than would be expected when considering peripheral parasitaemia alone.
Authors’ original file for figure 112936_2012_2463_MOESM1_ESM.tiff
World Health Organization: Guidelines for the treatment of malaria. 2010, http://www.who.int/malaria/publications/atoz/9789241547925/en/index.html., second editionth
World Health Organization: Communicable Diseases Cluster: Severe falciparum malaria. Trans R Soc Trop Med Hyg. 2000, 94 (Suppl 1): S1-S90. CrossRef
van Genderen PJ, Hesselink DA, Bezemer JM, Wismans PJ, Overbosch D: Efficacy and safety of exchange transfusion as an adjunct therapy for severe Plasmodium falciparum malaria in nonimmune travelers: a 10-year single-center experience with a standardized treatment protocol. Transfusion. 2010, 50: 787-794. 10.1111/j.1537-2995.2009.02488.x. CrossRefPubMed
van Wolfswinkel ME, Hesselink DA, Zietse R, Hoorn EJ, van Genderen PJ: Hyponatraemia in imported malaria is common and associated with disease severity. Malar J. 2010, 25: 140- CrossRef
van Wolfswinkel ME, Hesselink DA, Hoorn EJ, de Rijke YB, Koelewijn R, van Hellemond JJ, van Genderen PJ: Copeptin does not accurately predict disease severity in imported malaria. Malar J. 2012, 5: 11-16.
Dondorp AM, Fanello CI, Hendriksen IC, Gomes E, Seni A, Chhaganlal KD, Bojang K, Olaosebikan R, Anunobi N, Maitland K, Kivaya E, Agbenyega T, Nguah SB, Evans J, Gesase S, Kahabuka C, Mtove G, Nadjm B, Deen J, Mwanga-Amumpaire J, Nansumba M, Karema C, Umulisa N, Uwimana A, Mokuolu OA, Adedoyin OT, Johnson WB, Tshefu AK, Onyamboko MA, Sakulthaew T, Ngum WP, Silamut K, Stepniewska K, Woodrow CJ, Bethell D, Wills B, Oneko M, Peto TE, von Seidlein L, Day NP, White NJ, AQUAMAT group: Artesunate versus quinine in the treatment of severe falciparum malaria in African children (AQUAMAT): an open-label, randomised trial. Lancet. 2010, 376: 1647-1657. 10.1016/S0140-6736(10)61924-1. PubMedCentralCrossRefPubMed
- The prognostic value of schizontaemia in imported Plasmodium falciparum malaria
Marlies E van Wolfswinkel
Mariana de Mendonça Melo
Jaap J van Hellemond
Perry J van Genderen
- BioMed Central
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