Diagnostic uncertainty has been described as a clinician perception that affects diagnostic evaluation and can lead to diagnostic errors and negative patient outcomes. This single site cross-sectional study describes the clinical characteristics and healthcare utilization among pediatric patients prospectively identified as having an ‘uncertain diagnosis’ (defined as patients with high likelihood to have a different diagnosis resulting in a change in management). Of the 200 patients meeting inclusion criteria, 45% had gastrointestinal symptoms (e.g., vomiting, abdominal pain, diarrhea). Five percent of patients (5%) required a rapid response team and 3.5% were transferred to intensive care. The authors suggest that better methods to prospectively identify patients with an ‘uncertain diagnosis’ can result in optimized care for these patients.