Clinical approach to fever of unknown origin in children

Fever of unknown origin (FUO) can be caused by many clinical conditions and remains a diagnostic challenge in clinical practice. The etiology of FUO varies markedly among different age groups, geographic areas, and seasons. A four-stage investigative protocol for FUO is widely applied in clinical practice. The aim of this study was to evaluate the usefulness of this four-stage protocol for identifying the etiology of FUO in children.

We enrolled children younger than 18 years of age who were admitted to the Taichung Veterans General Hospital during the period from January 2006 to December 2014 with FUO persisting for more than 3 weeks. The four-stage FUO investigative guideline was used to evaluate the etiology of fever in all patients enrolled in the study.

The etiology of FUO was identified in 79 (84.9%) of the 93 patients enrolled in the study. The most common cause of FUO was infectious disease (37.6%), followed by malignancy (17.2%), miscellaneous disease (16.1%), and collagen vascular disease (14.0%). With respect to the four-stage survey of FUO, 36 of the 79 patients (45.6%) were identified in Stage 3, 28 patients (35.4%) in Stage 2, 13 patients (16.5%) in Stage 4, and only two patients (2.5%) in Stage 1.

A well-designed systemic review of the epidemiological information, medical history, physical examination, laboratory analysis, and adequate invasive procedures provide adequate data to identify the most common causes of FUO in children.