What term describes a situation where fever occurs without an identifiable source?

The term that best describes a situation where a fever occurs without an identifiable source is "Fever without source." This phrase specifically emphasizes the absence of a clear cause for the fever during the evaluation of pediatric patients. In clinical practice, it is commonly used when a physician observes an elevated body temperature but cannot pinpoint any specific infectious or pathological reason following a thorough assessment, including medical history and physical examination.

The use of "Fever without source" is particularly relevant in pediatric care, as children often present with fever due to several benign reasons that might not always be evident right away. This term aligns with pediatric guidelines and appropriately captures the essence of the clinical situation, prompting further investigation when necessary.

Other terms, such as "Fever of unknown origin," typically refer to cases where the fever persists for more than a certain time frame (e.g., more than three weeks), and some amount of evaluation has been done without identifying a cause. "Idiopathic fever" suggests that the cause is unknown despite thorough investigation, not simply that a source hasn't been identified yet. "Acute fever" is a more general term that describes any fever that occurs suddenly and lasts for a short period without specifically addressing the underlying cause. Therefore, "Fever without source" is