Q87.11

Clinical Causes: Deletion of a segment on the paternal chromosome 15 Maternal uniparental disomy (inheritance of two copies of chromosome 15 from the mother) Imprinting defects affecting gene expression on chromosome 15

Key Symptoms: Poor muscle tone (hypotonia) in infancy Delayed development and motor milestones Intellectual impairments and learning difficulties Extreme hunger leading to overeating (hyperphagia) Obesity if unmanaged Short stature and abnormal facial features Behavioral issues such as temper tantrums, stubbornness, and obsessive-compulsive tendencies Delayed or incomplete sexual development Sleep disturbances including sleep apnea Skin picking and other compulsive behaviors

Diagnosis Path: Diagnosis of Prader-Willi syndrome typically involves a combination of clinical assessments and genetic testing. Healthcare providers look for characteristic physical features and behavioral signs. Confirmatory tests include DNA methylation analysis, fluorescence in situ hybridization (FISH), or chromosomal microarray to identify the specific genetic abnormalities associated with PWS.

Treatment Protocols: Growth hormone therapy to increase height, improve muscle tone, and reduce body fat Dietary management to control weight and prevent obesity Structured behavioral therapy and educational support to address behavioral challenges Monitoring and treatment of hormone deficiencies, such as hypogonadism Regular ophthalmologic, audiologic, and medical check-ups to address associated health issues Support for sleep disorders, including sleep studies and potential treatments for sleep apnea