Urodynamic characterization of giggle incontinence in children.

Aims Giggle incontinence is a rare condition resulting in excessive urinary incontinence with laughter, where bladder function is otherwise "normal." Urodynamic descriptions of the condition to date are limited. We believe that giggle incontinence has characteristic urodynamic findings. We tested this hypothesis. Methods We retrospectively reviewed the urodynamic investigations of patients with giggle incontinence managed in a tertiary regional bladder unit between February 2014 and November 2019. Results We identified the studies of seven patients, median age 13.5 years (10.4-15.7) of whom 6 were female. All had videourodynamics. Two went on to have further invasive investigation; one had urethral pressure profile and one had ambulatory urodynamics. Detrusor overactivity (DO) was observed in six. DO was asensate in all. In five DO was triggered by laughter and was associated with laughter induced incontinence in four. Six had DO that was not provoked by laugher. In one amplitude of DO was proportional to vigour of laughter. In three patients there was identification of sudden pelvic floor relaxation during laughter resulting in incontinence. Stress urinary incontinence was not observed in any. Conclusions Giggle incontinence is a complex phenomenon. Urodynamic diagnosis is challenging and is dependent on eliciting laughter. We present the first urodynamic demonstration that giggle incontinence is associated with laughter-induced, asensate DO and concurrent, momentary pelvic floor relaxation. We hope this will provide a more consistent basis for defining this condition in the future.