Hypogonadisms

This observational natural history study will follow individuals with MEHMO (Mental disability, Epileptic seizure, Hypopituitarism/Hypogenitalism, Microcephaly, Obesity) syndrome or an eIF2-pathway related disorder, who have symptoms such as intellectual delay, seizures, abnormal hormone and blood sugar levels, and decreased motor skills. No current treatment for these conditions is available. A major impediment to the testing of potential therapeutic interventions is the lack of well-defined outcome measures. This protocol seeks to identify biochemical and clinical markers to monitor disease progression, and better understand the natural history of these conditions. Any person diagnosed with MEHMO syndrome or related conditions, who can travel to the NIH Clinical Center can participate in this study. The study involves: * General health assessment and evaluation * Imaging studies * Laboratory tests * Collection of blood, urine, spinal fluid, skin biopsy.

This study evaluates bone mineral density (BMD) in pediatric patients aged 5-18 years with conditions negatively affecting bone health, using REMS (Radiofrequency Echographic Multi Spectrometry), a non-invasive and radiation-free ultrasound technology. Bone health is crucial during childhood, when peak bone mass develops, and reduced BMD is associated with increased fracture risk. DXA is the current reference method but has limitations in children, including radiation exposure and growth-related measurement issues. REMS has been validated in adults and shows promise in pediatrics, despite the lack of reference values. The study is a single-center, national, non-profit interventional study lasting about 12 months. Participants will undergo REMS BMD measurement, clinical history collection, and assessment of anthropometric and pubertal parameters, with prior DXA data collected when available. The primary aim is to describe BMD values measured by REMS in pediatric osteoporosis, with secondary aims including subgroup analyses and comparison with DXA. A sample of 100 patients is planned. Statistical analyses will assess BMD distributions, correlations with clinical variables, and agreement between REMS and DXA using correlation coefficients and Bland-Altman analysis.