E83.31
BillableFamilial hypophosphatemia
HCC Category Mapping
V28HCC 50 — Glycogen/Amino-Acid/Other Metabolic Disorders
0.289RxHCCHCC 42 — Endocrine Disorders and Metabolic Conditions
0.000What This Code Means
Familial hypophosphatemia is an inherited condition where the body cannot properly regulate phosphate levels, resulting in abnormally low phosphate in the blood. This genetic disorder affects how the kidneys handle phosphate and can lead to weak bones and other complications.
Coding Tips
- •This code is specific to familial (inherited) hypophosphatemia; do not use it for hypophosphatemia due to other causes such as malnutrition, medications, or refeeding syndrome
- •Document the family history and genetic nature of the condition in the medical record to support the use of this specific code rather than the more general hypophosphatemia codes
Clinical Significance
Familial hypophosphatemia (including X-linked hypophosphatemia) is a rare hereditary disorder of renal phosphate wasting that causes rickets in children and osteomalacia in adults. It requires lifelong management with phosphate supplements and active vitamin D, and its chronic nature makes it significant for risk adjustment.
Documentation Requirements
- ✓Confirmed familial/hereditary etiology of hypophosphatemia
- ✓Genetic testing results if available (PHEX, FGF23-related mutations)
- ✓Serum phosphorus levels and renal phosphate wasting documentation
- ✓Current treatment regimen (phosphate supplements, calcitriol, burosumab)
- ✓Assessment of skeletal complications (rickets, osteomalacia, fractures, dental abnormalities)
- ✓Family history supporting hereditary nature
Excludes 1 — Do NOT code together
- vitamin D-deficiency rickets (E55.0)
Commonly Confused Codes
E83.30 — Disorder of phosphorus metabolism, unspecified: lacks the specificity and HCC mapping of familial hypophosphatemiaE83.39 — Other disorders of phosphorus metabolism: use for acquired or non-familial phosphorus disordersE55.0 — Rickets, active: nutritional rickets from vitamin D deficiency, not genetic phosphate wastingN25.0 — Renal osteodystrophy: secondary phosphorus disorder from chronic kidney disease
Code Hierarchy
└E83Disorders of mineral metabolism└E83.3Disorders of phosphorus metabolism and phosphatases└E83.31Familial hypophosphatemia
└E83.31Familial hypophosphatemia