CHS Audit: Young Males Dominated ER Presentations, with 43% Returning Within the Study Period

142 presentations from 67 unique patients. 43% (29 patients) represented during the study period, most within 3 months. Males were overrepresented (68.7%). Median age was 31. All had daily cannabis use. Cyclical nausea/vomiting was the most common feature. Lab findings: elevated white cells with neutrophilia (75.8%), mild low potassium (57.9%), normal lipase, and low CRP.

Retrospective chart review of adult CHS presentations at an urban Melbourne ED from January 2015 to January 2021. Examined demographics, cannabis use patterns, clinical features, lab results, imaging, treatment, and outcomes including re-presentation rates.

The high re-presentation rate (43%) highlights CHS as a chronic, recurring condition that significantly burdens emergency departments. The lab profile (normal lipase, low CRP) could help clinicians distinguish CHS from other causes of cyclic vomiting.

This Australian data complements North American CHS studies, showing the condition is a global phenomenon. The detailed lab characterization is particularly useful for developing diagnostic criteria, as CHS remains a diagnosis of exclusion.

Single-center retrospective study in outer Melbourne. CHS diagnosis depended on documentation, which may vary by clinician. Patients who sought care elsewhere would be missed. The study could not assess cannabis cessation rates or long-term outcomes.