Incidence, severity, prognostic significance of thrombocytopenia in malaria
Keywords:Complicated malaria, Mixed infections, Malarial antigen assay, Plasmodium, Quantitative buffy coat (QBC), Thrombocytopenia
Background: Malaria is an infectious disease caused by plasmodium parasite. P. falciparum account for majority of morbidity and mortality. Thrombocytopenia and anaemia are the most frequently associated hematological complications in malaria. The low platelet count together with acute febrile syndrome emerged as the strongest predictor of malaria a finding that is frequent and present even before anemia and splenomegaly sets in. Severe thrombocytopenia is a good predictor of poor prognosis than mild and moderate thrombocytopenia. The aim is to study the incidence, severity, prognostic significance of thrombocytopenia in malaria.
Methods: This was an observational and prospective study. The study enrolled 100 patients with thrombocytopenia and fever who were proven to have malaria either by peripheral smear or Quantitative Buffy Coat (QBC) test or malarial antigen assay were included in the study and patients with thrombocytopenia due to other causes were excluded from the study. Platelet count was estimated on a fully automated quantitative analyzer. All the 100 patients were followed during the hospital stay and upto discharge or till the outcome.
Results: The incidence of thrombocytopenia was 73% indicating a common association in malaria. Complicated malaria was observed in 58.80% of P. falciparum infection whereas 66% of P. vivax infection was associated with uncomplicated malaria. Severe thrombocytopenia showed positive correlation with severity of malaria. Thrombocytopenic patients with effective anti-malarial treatment showed 95.90% recovery and 3 patients 4.10% had mortality. Patients with severe thrombocytopenia were 8.5 times more likely to have complicated malaria with P <0.001 according to student ‘t’ test.
Conclusion: Thrombocytopenia is the most common hematological finding in malaria. Severe thrombocytopenia showed positive correlation with complicated malaria and a good predictor of poor prognosis. Patients with classical malarial fever and thrombocytopenia who were negative for malaria parasite were not included in the study.
Longo D, Fauci A, Kasper D, Hauser S, Jameson J, Loscalzo J. History of the discovery of the malaria parasites and their vectors: parasites & vectors. In: Longo D, Fauci A, Kasper D, Hauser S, Jameson J, Loscalzo J, eds. Harrisons Principles of Internal Medicine. 18th ed. New York: McGraw-Hill Professional; 2011: 3-5.
Mohapatra MK, Sethi G, Das SP, Patnaik SR. Incidence, outcome and predictive factors of falciparum malaria with multiorgan failure. J Assoc Physicians India. 2001;49:149-50.
WHO. Malaria: world report, 2012. Available at: http://www.who.int/malaria/publications/world_malaria_report_2012/en/.
Wickramasinghe SN, Abdullah SH. Blood and bone marrow changes in malaria. Ailliere’s Best Pract Res Clin Hematol. 2000;13(2):277-99.
D’Acremont V, Landry P, Mueller I, P´ecoud A, Genton B. Clinical and laboratory predictors of imported malaria in an outpatient setting: an aid to medical decision making in returning travellers with fever. Am J Trop Med Hyg. 2002;66(5):481-6.
Flemina, Menendez C. Malaria related anaemia. Parasitol Today. 2000;16:476-496.
Jamal Khan SS, Khan FR, Usman M, Zahid S. Malaria can lead to thrombocytopenia. Rawal Med J. 2008;33(2):183-5.
Yamaguchi S, Kubota T, Yamagishi T, Okamoto K, Izumi T, Takada M, et al. Severe thrombocytopenia suggesting immunological mechanisms in two cases of vivax malaria. Am J Hematol. 1997 Nov;56(3):183-6.
Casals-Pascual C, Kai O, Newton CR, Pasha N, Roberts DJ. Thrombocytopenia in falciparum malaria is associated with high concentrations of IL-10. Am J Trop Med Hyg. 2006 Sep;75(3):434-6.
WHO. Guidelines for the treatment of malaria. In: WHO, eds. WHO Guideline. Geneva: World Health Organization; 2006: 72.
WHO. Assessment of the safety of artemisinin compounds in pregnancy. In: WHO, eds. WHO Document - Malaria. Geneva: World Health Organization; 2007: 1-54.
Talib VH, Hajira BD, Diwan VM, Verma MC. A clinico-hamatological profile of malaria. J Assoc Physicians India. 1982;30(6):402-4.
Murthy GL, Sahay RK, Srinivasan VR, Upadhaya AC, Shantaram V, Gayathri K. Clinical profile of falciparum malaria in a tertiary care hospital. J Indian Med Assoc. 2000 Apr;98(4):160-2.
Mehta SR, Naidu G, Chandra V, Singh IP, Johri S, Ahuja RC. Falciparum malaria present day problems-an experience with 425 cases. J Assoc Physicians India. 1989;37(4):264-7.
Kocher D, Kumawat BL, Karan S. Severe and complicated malaria in Bikaner, Western India. Southeast Asian J Trop Med. 1997 Jun;28(2):259-67.
Jadhav UM, Patkar VS, Kadam NN. Thrombocytopenia in malaria: correlation with type & severity of malaria. J Assoc Physicians India. 2004;52:615-8.
Kumar A, Sasirekha. Thrombocytopenia: an indicator of acute vivax malaria. Indian J Pathol Microbiol. 2006 Oct;49(4):505-8.
Mahmood A, Yasir M. Thrombocytopenia: a predictor of malaria among febrile patients in Liberia. Infect Dis J. 2008;14:41-4.
Kochar DK, Das A, Kochar A, Middha S, Acharya J, Tanwar GS, et al. Thrombocytopenia in plasmodium falciparum Plasmodium vivax and mixed infection malaria: a study from Bikaner (North-western, India). Platelets. 2010;21(8):623-7.