Excludes1 pair
E21.3 vs E83.5-
E21.3 and E83.5 are not coded together. ICD-10-CM declares them mutually exclusive with an Excludes1 note — the two conditions are not expected to occur together, so exactly one of them is normally correct for a given encounter. The Official Guidelines carve out one exception: if the two conditions are clearly unrelated to each other, both may be reported.
The official note, declared on E83.5
hyperparathyroidism (E21.0-E21.3)
E21.3
Hyperparathyroidism, unspecified
BillableUnspecified
- Chapter 4
- Endocrine, nutritional and metabolic diseases
- Section
- E20-E35
Indexed under
- Hyperparathyroidism
- Hyperfunction › parathyroid (gland)
- Arthritis, arthritic › in › hyperparathyroidism NEC
- Myopathy › in › hyperparathyroidism NEC
- Arthropathy › hemophilic NEC › in › hyperparathyroidism NEC
E83.5
Disorders of calcium metabolism
Not billable
- Chapter 4
- Endocrine, nutritional and metabolic diseases
- Section
- E70-E88
Excludes1 is not always absolute: where two conditions covered by the note are genuinely unrelated, CMS guidance permits reporting both. Document the reasoning rather than assuming it. More on Excludes1 vs Excludes2 · FY2027