Missed time-sensitive diagnoses following urgent primary care assessment: a systematic review of diagnostic failures and subsequent emergency or acute hospital care

Background: Urgent primary care is an important entry point for patients with serious acute illness. Diagnostic uncertainty complicates early recognition. This review examined missed diagnoses, diagnostic delays, and under-triage preceding emergency or acute hospital assessment. Methods: Published original studies available through 31 Jan 2026 were examined. Studies addressed initial general practice, urgent care, or out-of-hours assessment with subsequent diagnostic follow-up. Findings were grouped by condition and outcome definition, using narrative synthesis. Results: Ten original reports addressed coronary syndromes, sepsis, pulmonary embolism, stroke, and appendicitis. In 2,023 chest-discomfort callers, final telephone urgency allocation had 86% sensitivity for coronary syndromes or other life-threatening events. In a sepsis cohort, infection was unsuspected in 43 of 100 patients examined by general practitioners. Pulmonary embolism studies identified substantial primary-care delay, including delays exceeding seven days in 33 of 128 patients with preceding relevant consultations. Among 291 children with appendicitis in a primary-care cohort, 55 were initially misdiagnosed. A Danish stroke-pathway study reported 63.1% sensitivity for stroke or transient ischaemic attack recognition. Conclusions: Diagnostic problems occurred in several urgent primary-care pathways. Under-triage represented a distinct outcome from confirmed diagnostic error. Findings support condition-specific assessment, explicit reassessment arrangements, and better linkage between primary-care encounters and subsequent emergency diagnoses, while restricting conclusions to the settings and outcomes studied.