Assessment of World Health Organization definition of dengue hemorrhagic fever in North India.

BACKGROUND Classification of symptomatic dengue according to current World Health Organization (WHO) criteria is not straightforward. In this prospective study of dengue infection during an epidemic in India in 2004, we applied the WHO classification of dengue to assess its usefulness for our patients. METHODOLOGY The study included 145 clinically suspected cases of dengue infection of all ages. Dengue was confirmed by serological methods (IgM ELISA and HI test). WHO criteria were applied to classify dengue positive patients into Dengue Fever (DF), Dengue Hemorrhagic Fever (DHF) and Dengue Shock Syndrome (DSS). Clinical and laboratory parameters were compared between dengue patients with bleeding and those without bleeding. RESULTS Out of the 50 serologically positive cases of dengue enrolled in the study, only 3 met the WHO criteria for DHF and 1 met the criteria for DSS; however, 21 (42%) cases had one or more bleeding manifestations. CONCLUSION By using WHO criteria of DHF on Indian patients, all severe cases of dengue cannot be correctly classified. A new definition of DHF that considers geographic and age-related variations in laboratory and clinical parameters is urgently required.