Alphabetic Index FY2027

E21.5

Disorder of parathyroid gland, unspecified

FY2027Chapter 4: Endocrine, nutritional and metabolic diseases/E20–E35 Disorders of other endocrine glands

BillableComplete code, valid to report

E21.5 (also written E215) is a billable ICD-10-CM diagnosis code for disorder of parathyroid gland, unspecified. It is part of the FY2027 code set, effective October 1, 2026. It is one of the 6 codes in category E21 (Hyperparathyroidism and other disorders of parathyroid gland). The Alphabetic Index lists it under 2 entries. Its coding notes include 7 Excludes1 entries and 1 Excludes2 entry.

Excludes1

Not coded here. The listed conditions generally should not be reported together.

Inherited from E21 Hyperparathyroidism and other disorders of parathyroid gland
  • adult osteomalacia (M83.-)
  • ectopic hyperparathyroidism (E34.2)
  • hungry bone syndrome (E83.81)
  • infantile and juvenile osteomalacia (E55.0)
Also from chapter/block level (3 notes)
Inherited from E20–E35 Disorders of other endocrine glands
Inherited from Chapter 4 Endocrine, nutritional and metabolic diseases
  • transitory endocrine and metabolic disorders specific to newborn (P70-P74)

Excludes2

Not included here. Both codes may be reported if the patient has both conditions.

Inherited from E21 Hyperparathyroidism and other disorders of parathyroid gland
  • familial hypocalciuric hypercalcemia (E83.52)

Notes

Also from chapter/block level (1 note)
Inherited from Chapter 4 Endocrine, nutritional and metabolic diseases
  • All neoplasms, whether functionally active or not, are classified in Chapter 2. Appropriate codes in this chapter (i.e. E05.8, E07.0, E16-E31, E34.-) may be used as additional codes to indicate either functional activity by neoplasms and ectopic endocrine tissue or hyperfunction and hypofunction of endocrine glands associated with neoplasms and other conditions classified elsewhere.

Alphabetic Index terms

Terms the official Alphabetic Index lists for this code. 2 entries