Diagnostic approach to a child with fever of unknown origin
DOI:
https://doi.org/10.13112/pc.1077Keywords:
FEVER OF UNKNOWN ORIGIN; CHILD; INFECTIONS; RHEUMATIC DISEASES; HEREDITARY AUTOINFLAMMATORY DISEASES; NEOPLASMSAbstract
Fever of unknown origin is a relatively common condition in pediatrics that continues to present a diagnostic challenge. A fever of unknown (unexplained) origin in children is defined as a fever that persists for 8 days or longer, and the history, clinical examination, and basic laboratory findings have not revealed the cause of the fever. Infections are still the leading cause of fever of unknown origin in children, but in the case of prolonged fever, in addition to infections, rheumatic, autoimmune, autoinflammatory, granulomatous, malignant diseases or tumors, and other rare diseases should be considered. When approaching this problem, special attention should be paid to the history and a thorough examination, which should be repeated on several occasions. Sometimes, first-line laboratory tests, together with first-level imaging, allow us to exclude the most common and/or serious causes of fever of unknown origin and indicate whether we should continue with further workup. Subsequent workup should be directed according to the diagnostic suspicion, and further laboratory and imaging workup should be planned wisely.
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