Severe Lower Urinary Tract Dysfunction in Otherwise Healthy Children: Report of Three Cases and Narrative Review

Background: Severe lower urinary tract dysfunction (LUTD) in neurologically and anatomically normal children is uncommon but clinically significant, often mimicking structural pathology and predisposing to recurrent urinary tract infections (rUTIs) and upper tract deterioration. This narrative review synthesizes current evidence on the diagnosis and management of severe functional LUTD and presents three illustrative pediatric cases that exemplify relevant phenotypes. Methods: A structured narrative review covering 1970–2024 was conducted using PubMed, Scopus, and Web of Science, focusing on severe functional LUTD and Hinman syndrome in children. Three representative cases (ages 3–10 years) from a tertiary pediatric urology center were integrated to contextualize diagnostic considerations and therapeutic strategies. Results: The cases demonstrated the spectrum of severe functional LUTD: (1) detrusor overactivity with reduced capacity; (2) poor compliance with detrusor–sphincter dyssynergia and secondary high-grade reflux (Hinman syndrome); and (3) detrusor underactivity with recurrent retention. All patients exhibited bladder wall remodeling on cystoscopy despite normal neuroanatomy. Across phenotypes, multimodal functional therapy—urotherapy, pelvic floor biofeedback, targeted pharmacotherapy, and when indicated continuous antibiotic prophylaxis or intermittent catheterization—resulted in resolution of rUTIs and improvement in bladder dynamics. Severe functional LUTD may closely resemble anatomical obstruction or primary vesicoureteral reflux, resulting in misdiagnosis and potentially unnecessary or ineffective surgical interventions. The presented cases underscore that early recognition of a functional etiology is crucial to avoid iatrogenic harm and to ensure timely, conservative management. Conclusions: Severe functional LUTD represents an under-recognized yet reversible condition within the non-neurogenic voiding disorder spectrum. A function-first diagnostic approach emphasizing urodynamic phenotyping and selective use of invasive imaging is essential to prevent misdiagnosis, avoid unnecessary surgery, and protect renal function. Coordinated, multidisciplinary conservative management remains the cornerstone of effective treatment.