A Clinico-Epidemiological Profile and Etiological Spectrum of Fever of Unknown Origin in Children Age 1–17 Years: A Prospective Observational Study from a Tertiary Care Centre in North India

Abstract

Background: Fever of unknown origin (FUO) remains a major diagnostic challenge in paediatric practice because of its diverse etiologies and variable clinical manifestations. Contemporary prospective data from North-Western India are limited.

Objectives: To evaluate the clinico-epidemiological profile and etiological spectrum of fever of unknown origin among children age 1–17 years admitted to a tertiary care centre.

Methods: A hospital-based prospective observational study was conducted in the Department of Paediatric Medicine, Sir Padampat Institute of Neonatology and Paediatric Health, SMS Medical College, Jaipur, from June 2024 to May 2025. Eighty children fulfilling the predefined criteria for fever of unknown origin were enrolled. Demographic characteristics, clinical features, laboratory investigations, imaging findings, and final diagnoses were recorded using a standardized protocol. Statistical analysis was performed using SPSS version 26.0.

Results: The mean age of participants was 6.93 ± 5.15 years, with children age 1–5 years accounting for 53.75% of cases. Males predominated (61.25%). The mean duration of fever was 33.05 ± 13.6 days. Poor activity and appetite (81.25%) and weight loss (51.25%) were the most frequent presenting features. Anaemia was the commonest haematological abnormality (66.25%). Infectious diseases represented the predominant etiological group (83.75%), followed by malignancies (8.75%), undiagnosed cases (5.0%), and connective tissue diseases (2.5%). Tuberculosis (47.5%) and brucellosis (25.0%) were the leading final diagnoses. Thrombocytopenia, leukopenia, neutropenia, and pancytopenia showed significant associations with malignant disorders.

Conclusions: Infectious diseases, particularly tuberculosis, remain the principal cause of paediatric fever of unknown origin in this region. A structured, stepwise diagnostic approach supported by targeted laboratory investigations facilitates early diagnosis and appropriate management while reducing unnecessary investigations and empirical antimicrobial therapy.