Clinical Scoring System to Predict Malarial Fever: A Prospective Study

Background: Malaria is the most important infectious disease of mankind. Though, smear examination is gold standard in diagnosing malaria, it has many drawbacks particularly in developing countries. Methods: A prospective study was designed with duration of the study was six months. Based on previous work, we identified the most specific clinical features of malaria and assigned with score. Maximum score was 14. Only adult patients with more than 13 years of age with complaint of fever were included for the study. Clinical Score was calculated for each patient by two different persons (clinician and intern). All the patients were subjected for peripheral smear by specialist or trained person to diagnose malaria. Clinical Score were compared with smear diagnosis of malaria. Sensitivity, specificity, positive predictive value (PPV) and negative predictive values (NPV) for each score were analyzed. Receiver Operative Curve (ROC) was prepared to assign a particular score which can diagnose malaria with good certainty. Results: A total of 142 consecutive fever cases were included in the study. 67 (47.18%) cases were of malaria and rests were control cases. Using score of more than eight, the sensitivity, specificity, positive predictive value and negative predictive value of clinical scoring system to detect malaria (either vivax or falciparum) were 95.52%, 85.33%, 85.33% and 95.52% respectively. Using score of more than nine, the same statistics were 91.04%, 93.33%, 92.42% and 92.10% respectively. Using ROC curve score more than or equal to nine can give the clinical diagnosis of malaria with good certainty. Conclusion: Score more than nine can be used in clinics to assign as malaria with good confidence and can be treated empirically with antimalarials. This score can substitutes smear examination however, can not replace it. This scoring system is very helpful where smear examination is remote possibility or it can not be relied upon due to technical or staff problem specifically in rural part of India or peripheral health centre with least facilities.