Can hematological parameters discriminate malaria from nonmalarious acute febrile illness in the tropics?
BACKGROUND
Malaria is considered as the main differential diagnosis of acute febrile illness in the tropics, and alteration of various hematological parameters has been observed in patients with malaria.


OBJECTIVE
To ascertain if certain hematological parameters increase the probability of malaria in patients with acute febrile illnesses.


METHODS
Hospital based, prospective cohort study.


METHODS
All consecutive in patients with fever of less than seven days in duration were included in the study. Patients where localizing cause for fever could be determined were excluded. Hematological parameters (Hemoglobin, Red cell distribution width (RDW), Leukocyte count, and platelet counts) were determined by using automated counter, and peripheral smear examination for malarial parasite was taken as gold standard for the diagnosis of malaria.


METHODS
Diagnostic accuracy was measured by computing sensitivity, specificity, predictive values and likelihood ratios. The precision of these estimates was evaluated using 95% confidence intervals.


CONCLUSIONS
A total of 184 patients were included in the study and 70 (38%) had a positive peripheral smear for malarial parasite. Thrombocytopenia alone (platelet countless than 150,000/mm3) was a predictor for malaria (Sn 60%, Sp 88%, LR+ 5.04) and in combination with anemia (Hb < 10 g/dl) it was next best parameter (Sn 69%, Sp 74%, LR+ 2.77). RDW and leukocyte count were not predictive. The conclusion of this study is that the presence of thrombocytopenia in a patient with acute febrile illness increases the probability of malarial infection.
Lathia
T B
TB
Department of Medicine, Mahatma Gandhi Institute of Medical Sciences, Sevagram, Maharashtra-442 102, India.
Joshi
R
R
D000208:Acute Disease; D000328:Adult; D003937:Diagnosis, Differential; D004909:Erythrocyte Indices; D005260:Female; D005334:Fever / Q000209:etiology*; D006454:Hemoglobins / Q000032:analysis; D006801:Humans; D016778:Malaria, Falciparum / Q000097:blood / Q000175:diagnosis*; D016780:Malaria, Vivax / Q000097:blood / Q000175:diagnosis*; D008297:Male; D010976:Platelet Count; D011237:Predictive Value of Tests; D012680:Sensitivity and Specificity; D014329:Tropical Climate
D006454:Hemoglobins