ICD-10-CM 2027
ICD-10 code for postinfectious hypothyroidism
From the official ICD-10-CM alphabetic index entry “Hypothyroidism (acquired) › postinfectious”. Page updated September 29, 2026.
About coding postinfectious hypothyroidism
The ICD-10-CM code for postinfectious hypothyroidism is E03.3 (Postinfectious hypothyroidism).
Within E03 (other hypothyroidism), E03.3 is specifically for postinfectious hypothyroidism. Related codes cover congenital hypothyroidism with diffuse goiter (E03.0), congenital hypothyroidism without goiter (E03.1), hypothyroidism due to medicaments and other exogenous substances (E03.2), atrophy of thyroid (acquired) (E03.4), myxedema coma (E03.5), other specified hypothyroidism (E03.8) and hypothyroidism, unspecified (E03.9).
It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.
In MS-DRG v44.0, it is part of the grouping logic for DRG 643 (Endocrine Disorders with MCC, relative weight 1.6139), DRG 644 (Endocrine Disorders with CC, relative weight 1.0044) and DRG 645 (Endocrine Disorders without CC/MCC, relative weight 0.7459), in MDC 10 (Endocrine, Nutritional and Metabolic Diseases and Disorders), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.
Common questions about postinfectious hypothyroidism ICD-10 codes
What is the ICD-10 code for postinfectious hypothyroidism?
- E03.3 — Postinfectious hypothyroidism.
Is E03.3 billable?
- Yes. E03.3 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can E03.3 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict E03.3 as a principal diagnosis.
Is E03.3 a CC or MCC?
- No. E03.3 is neither a CC nor an MCC under MS-DRG v44.0.