Regional Clustering of Giggle Incontinence in Toyserkan, Iran: A Case Series of 20 Patients

Abstract Purpose Giggle incontinence (enuresis risoria) is a rare condition characterized by complete involuntary bladder emptying triggered by laughter. Limited epidemiological data exist regarding its prevalence and geographic distribution.To report an unexpectedly high incidence of giggle incontinence cases in Toyserkan, Iran, and describe the clinical characteristics, treatment responses, and potential familial clustering in this regional population. Methods A retrospective case series of 20 consecutive patients diagnosed with giggle incontinence between 2023 and 2025 at Toyserkan Hospital. Clinical characteristics, family history, treatment modalities, and outcomes were systematically documented and analyzed. Results Twenty patients (age range: 4–19 years, mean age: 7.65 ± 2.38 years) were diagnosed with giggle incontinence in a city with a population of 100,000. The mean symptom duration before presentation was 1.5 years (range: 1–2 years). All patients presented with severe involuntary complete bladder emptying triggered exclusively by laughter. Diagnosis was confirmed through comprehensive history taking, physical examination, laboratory tests, and imaging studies. Familial clustering was observed in 15% of cases, including one family with three affected siblings. All patients initially received behavioral modifications, which showed poor adherence and minimal efficacy. Subsequently, all 20 patients were treated with tolterodine (1–2 mg every 12 hours). Treatment outcomes showed complete resolution in 3 patients (15%), partial improvement in 6 patients (30%), and no response in 11 patients (55%) after minimum 3-month trial. Long-term follow-up (minimum 2 years) revealed sustained response in most initial responders, with some spontaneous improvement in non-responders over time. The prevalence rate of 20 cases per 100,000 population over two years appears substantially higher than previously reported international rates. Conclusions This case series reveals a potential regional cluster of giggle incontinence in Toyserkan, Iran, with notable familial aggregation and treatment resistance. The findings suggest possible genetic predisposition or environmental factors specific to this geographic region, warranting further epidemiological investigation and genetic studies.