Abstract

Objectives: To determine the etiology of Fever of Unknown Origin (FUO) in children. Study Design: Prospective Observational study. Setting: Department of Pediatric Medicine, The Children's Hospital, Lahore. Period: August 2019 to January 2020. Material & Methods: A total of 45 children aged between 01 to 180 months (15 years), having FUO were included. FUO was defined as a temperature of greater than 100.4ºF documented by a health care provider, persisting over a period of three weeks and for which no cause could be identified after at least 8 days of evaluation. All the study information was analyzed by using standard software SPSS 20. The quantitative variables like age and duration of fever before hospital admission were presented as mean and standard deviation. Qualitative variables like sex, antibiotic therapy use before definitive diagnosis and various diagnoses made were presented as frequencies and percentages. Results: The patient’s age range was from 01 to 180 months with mean of 80±45.12 months and male to female ratio was 2.2:1. Definitive diagnosis was made in 37(82.2%) patients. Infections were the predominant cause of FUO (44.4%) followed by malignancy (24.4%). Tuberculosis was the most common infection while Acute Lymphoblastic leukemia dominated the malignancy. Systemic lupus erythematosus was the most commonly diagnosed connective tissue disorder.  There was a significant association between duration of fever and the ultimate diagnosis (p=0.01). Conclusion: Infectious diseases were the most common cause of FUO followed by malignancy, connective tissue disorders and miscellaneous causes.