Familial hypophosphatemia

This diagnosis code identifies a group of inherited disorders characterized by impaired renal phosphate reabsorption, leading to chronic hypophosphatemia. This metabolic disturbance results in bone abnormalities such as rickets in children and osteomalacia in adults, along with other systemic manifestations. The condition is typically X-linked dominant, but autosomal dominant and recessive forms also exist.

Assign this code for patients diagnosed with any form of familial hypophosphatemia, including X-linked hypophosphatemic rickets (XLH). Documentation should clearly indicate a genetic basis for the hypophosphatemia, often supported by family history, genetic testing results, or clinical presentation consistent with inherited phosphate wasting. This code is appropriate when the provider explicitly states "familial hypophosphatemia" or a specific inherited type.

• Do not code with E55.0 (Vitamin D-deficiency rickets) as these are distinct etiologies for rickets/osteomalacia.
• Ensure documentation specifies "familial" or "inherited" to differentiate from acquired causes of hypophosphatemia.
• Consider additional codes for specific manifestations, such as M83.0 (Adult osteomalacia due to malnutrition) or M83.1 (Non-allopathic osteomalacia of adults) if applicable and documented.