Characterization of platelet count and platelet indices and their potential role to predict severity in malaria

ABSTRACT

The association of hematological parameters especially platelet parameters with disease severity in malaria is poorly understood. We aimed to characterize the platelet parameters across Plasmodium falciparum and Plasmodium vivax malaria stratified by severity and to elucidate the potential role of platelet parameters to predict disease severity. Individuals > 18 years, of either gender with microscopically proven symptomatic malaria were prospectively enrolled between October 2014 and August 2016 in a tertiary center in Manipal, India. Severity of malaria was defined as per the WHO definition. Among 159 patients, 32 (20.1%) had severe malaria. 116 (73%) had infection with P. vivax, 37 (23%) P. falciparum and 6 mixed infection. Thrombocytopenia was seen in 32 (86.4%) of P. falciparum and 105 (90.5%) of P. vivax malaria cases. Patients with renal failure (p=0.02), shock (p=0.04) and liver dysfunction (p<0.001) had significantly lower platelet count compared to those who did not. Admission platelet count of 50,000 cell/mm³ had a sensitivity and specificity of 65.6% and 70.6% respectively, to discriminate severe malaria. A plateletcrit of 0.05% had a sensitivity and specificity of 65.6 % and of 70.6% respectively. Thrombocytopenia was seen in 89.3% of malaria cases due to both P. vivax and P. falciparum. Platelet count and plateletcrit could be used as markers of disease severity. P. vivax malaria which has been traditionally regarded as ‘benign’ can be as sinister and menacing as P. falciparum malaria and hence warrants equal attention. Unnecessary transfusion of platelets should be avoided.

KEYWORDS:

• Malaria
• platelet parameters
• disease severity
• hematological profile

Authors’ contributions

PG and KS: conception and design; PG and KS: acquisition of data; PG, VG and KS: analysis and interpretation of data; PG, VG and KS: drafting the manuscript or revising it critically for important intellectual content; PG, VG and KS: final approval of the version to be published and agree to be accountable for all aspects of the work.

Disclosure statement

No potential conflict of interest was reported by the authors.

Supplementary material

Supplementary data can be accessed here

Additional information

Funding

This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors