Lipin S Prasada, Sujathana, Ajith Ka
a. Department of Medicine, Travancore Medical College, Kollam, Kerala

Corresponding Author: Dr. Lipin S Prasad, Junior Resident, Department of Medicine, Travancore Medical College, Kollam, Kerala. Phone :09995859269. Email:


Malaria is an endemic disease in India. It is a mosquito-borne infectious disease caused by a eukaryotic protist of the genus Plasmodium. Thrombocytopenia frequently complicates malarial infections and usually noted in Plasmodium Falciparum. Here we report a case of Plasmodium vivax associated thrombocytopenia which is a rare presentation in P.vivax. He was initiated on anti malarial regimen as per WHO guidelines and showed significant improvement in symptoms and thrombocytopenia.

Case Summary


Table 1. Hematology

A 46 year old male got admitted with a history of fever since 3 days and gum bleeding since 2 days. No bleeding manifestation elsewhere from body. Fever was not associated with chills or rigors. He was a chronic alcoholic. Patient had travelled to coastal area of Tamil Nadu, India a week prior to admission. On general physical examination he is moderately built moderately nourished male weighing 64 kgs and a height of 158 cms. Bilateral mild non tender parotid enlargement noted, no pedal edema or clubbing was present.

Systemic examination was within normal except for mild non tender hepatomegaly. Clinical examination was suggestive of an arboviral illness hence routine blood investigation with peripheral smear study was done. Investigations revealed thrombocytopenia and peripheral smear showed Plasmodium Vivax     with moderate thrombocytopenia. Repeat smear was done in suspicion of Plasmodium Falciparum but smear did not reveal Falciparum. Hence, initiated on cloroquine and acetaminophen oral medication as per WHO guidelines for uncomplicated malarial infection. He showed significant improvement in symptoms and thrombocytopenia.

Viral Markers

Table 2. Viral Markers


Peripheral smear study
Plasmodium Vivax noted
Moderate thrombocytopenia


Malaria is a common infection in most parts of India and is commonly associated with mild thrombocytopenia.1 Profound thrombocytopenia is a well-recognized complication of falciparum malaria but has been less well described in vivax malaria.


Table 3. Serology

Of 173 cases of malaria in U.S. soldiers reported by Marteloet al2 in 1969, 93% had P. vivaxbut only 15% had thrombocytopenia with no documentation of the lowest platelet count. In Horstmann’s series,3 the lowest count in 39 cases of vivax malaria was 44×109/L. Pukrittayakamee et al.4 described a case of a volunteer experimentally infected with the Chesson’s strain of P. vivax with a platelet count of 20×109/L. Recently 2 cases of vivax malaria associated with an initial platelet count of 5×109/L and 8×109/L was reported from India.5 In our case, the patient presented with a severe thrombocytopenia of 39×109 /L, with spontaneous bleeding from the gums. This is probably one of the few case ever reported of isolated P. vivax infection causing such profound thrombocytopenia.

Table 4. Liver Function Test

Table 4. Liver Function Test

The mechanism of thrombocytopenia in malaria is not clearly known. Fajardo and Tallent6 in 1974 demonstrated P. vivax within platelets by electron microscopy and suggested a direct lytic effect of the parasite on the platelets. Both non-immunological destruction7 as well as immune mechanisms involving specific platelet-associated IgG antibodies that bind directly to the malarial antigen in the platelets have been recently reported to play a role in the lysis of platelets and the development of thrombocytopenia.8 In clinical trials, recombinant – macrophage colony stimulating factor (M-CSF) has been known to cause a reversible dose dependent thrombocytopenia. Elevated M-CSF levels in malaria, by increasing macrophage activity may mediate platelet destruction in such cases.9 Oxidative stress damage of thrombocytes has also been implicated in the etiopathogenesis based on the finding of low levels of platelet superoxide-dismutase and glutathione peroxidase activity and high platelet lipid peroxidation levels in malaria patients, when compared to those of healthy subjects.10 Since such severe thrombocytopenia is rare in vivax malaria, and mixed infection with falciparum and vivax is common in India, it could be argued that this case is associated with coexistent P. falciparum infection. Hence repeated blood sample was taken and closely observed for any falciparum infection co existing with the plasmodium vivax. The treatment was initiated as uncomplicated plasmodium vivax anti malarial treatment regimen as per new WHO guidelines and patient showed dramatic recovery in the symptoms and thrombocytopenia. No bleeding manifestation was noted later.

End Note

Author Information

  1. Dr. Lipin S Prasad, Junior Resident, Department of Medicine, Travancore Medical College, Kollam, Kerala.  Email: Phone: 09995859269
  2. Dr. Sujathan, Professor, Department of Medicine, Travancore Medical College, Kollam, Kerala.
  3. Dr. Ajith K, Department of Medicine, Travancore Medical College, Kollam, Kerala.    

Conflict of Interest: None declared


  1. Looareesuwan S, Davis JG, Allen DL, Lee SH, Bunnag D, White NJ. Thrombocytopenia in malaria. Southeast Asian J Trop Med Public Health. 1992 Mar;23(1):44–50. [Pubmed]
  2. Martelo OJ, Smoller M, Saladin TA. Malaria in American soldiers. Arch Intern Med. 1969 Apr;123(4):383–7. [Pubmed] | [Source]
  3. Horstmann R.D., Dietrich M., Bienzle U., Rasche H. Malaria. Blood 1991;42:157-64
  4. Pukrittayakamee S, White NJ, Clemens R, Chittamas S, Karges HE, Desakorn V, et al. Activation of the coagulation cascade in falciparum malaria. Trans R Soc Trop Med Hyg. 1989 Dec;83(6):762–6. [Pubmed]
  5. Kakar A, Bhoi S, Prakash V, Kakar S. Profound thrombocytopenia in Plasmodium vivax malaria. Diagn Microbiol Infect Dis. 1999 Nov;35(3):243–4. [Pubmed] | [Crossref]
  6. Fajardo L.F., Tallent C. Malarial parasites within human platelets. JAMA 1974;229:1205.  [Crossref]
  7. Looareesuwan S, Davis JG, Allen DL, Lee SH, Bunnag D, White NJ. Thrombocytopenia in malaria. Southeast Asian J Trop Med Public Health. 1992 Mar;23(1):44–50. [Pubmed]
  8. 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. [Pubmed] | [Crossref]
  9. Lee SH, Looareesuwan S, Chan J, Wilairatana P, Vanijanonta S, Chong SM, et al. Plasma macrophage colony-stimulating factor and P-selectin levels in malaria-associated thrombocytopenia. Thromb Haemost. 1997 Feb;77(2):289–93. [Pubmed]
  10. Erel O, Vural H, Aksoy N, Aslan G, Ulukanligil M. Oxidative stress of platelets and thrombocytopenia in patients with vivax malaria. Clin Biochem. 2001 Jun;34(4):341–4. [Pubmed] | [Crossref]