645 MS-DRG: ENDOCRINE DISORDERS WITHOUT CC/MCC
MS-DRG 645 groups Medicare inpatient hospital stays for: ENDOCRINE DISORDERS WITHOUT CC/MCC. This is a medical MS-DRG. It falls under MDC 10 (Endocrine, Nutritional and Metabolic Diseases and Disorders).
Payment & Classification Data
Official CMS values from the FY2027 IPPS Final Rule Table 5.
| Major Diagnostic Category | MDC 10 — Endocrine, Nutritional and Metabolic Diseases and Disorders |
| DRG Type | Medical |
| Severity Level | None |
| Relative Weight | 0.7459 |
| Relative Weight (10% Cap Applied) | 0.7459 |
| Geometric Mean Length of Stay | 2.6 days |
| Arithmetic Mean Length of Stay | 3.1 days |
| Post-Acute Transfer DRG | Yes |
| Special Pay Transfer DRG | No |
Defining Codes (FY2027)
199 diagnosis codes can drive assignment here: A18.7, A18.81, B67.31, C73, C74.00, C74.01, C74.02, C74.10, C74.11, C74.12, C74.90, C74.91 and 187 more.
From the CMS MS-DRG Definitions Manual (Appendices B and E). Assignment also depends on severity, discharge status and the rest of the claim.
Contextual Map
Every relationship of 645 in one view: hierarchy, official tabular instructions in both directions, clinical classification, risk adjustment, MS-DRG participation, index terms and change history — each edge carrying the CMS source it derives from.
Major Diagnostic Category
- MDC 10 — Endocrine, Nutritional and Metabolic Diseases and Disorders[MDC]— CMS MS-DRG Definitions Manual · FY2027
Defining diagnoses (199)
- A18.7 — Tuberculosis of adrenal glands[Grouper diagnosis]— CMS MS-DRG Definitions Manual (Appendix B) · FY2027
- A18.81 — Tuberculosis of thyroid gland[Grouper diagnosis]— CMS MS-DRG Definitions Manual (Appendix B) · FY2027
- B67.31 — Echinococcus granulosus infection, thyroid gland[Grouper diagnosis]— CMS MS-DRG Definitions Manual (Appendix B) · FY2027
- C73 — Malignant neoplasm of thyroid gland[Grouper diagnosis]— CMS MS-DRG Definitions Manual (Appendix B) · FY2027
- C74.00 — Malignant neoplasm of cortex of unspecified adrenal gland[Grouper diagnosis]— CMS MS-DRG Definitions Manual (Appendix B) · FY2027
- C74.01 — Malignant neoplasm of cortex of right adrenal gland[Grouper diagnosis]— CMS MS-DRG Definitions Manual (Appendix B) · FY2027
- C74.02 — Malignant neoplasm of cortex of left adrenal gland[Grouper diagnosis]— CMS MS-DRG Definitions Manual (Appendix B) · FY2027
- C74.10 — Malignant neoplasm of medulla of unspecified adrenal gland[Grouper diagnosis]— CMS MS-DRG Definitions Manual (Appendix B) · FY2027
- and 191 more
DRG family
- DRG 643 — ENDOCRINE DISORDERS WITH MCC[DRG family]: “ENDOCRINE DISORDERS WITH MCC — same CMS DRG family (643-645), split by severity.”— CMS MS-DRG Definitions Manual (DRG family 643-645) · FY2027
- DRG 644 — ENDOCRINE DISORDERS WITH CC[DRG family]: “ENDOCRINE DISORDERS WITH CC — same CMS DRG family (643-645), split by severity.”— CMS MS-DRG Definitions Manual (DRG family 643-645) · FY2027
Read from: CMS MS-DRG Definitions Manual (incl. Appendix B diagnosis index, Appendix C CC/MCC list, Appendix E procedure index) and IPPS Final Rule tables — v44. All data sources · How to read the labels · How MedCoder verifies its implementation
Current data releases:ICD-10-CM FY2027 · ICD-10-PCS FY2027 · HCPCS October 2026 · MS-DRG v44 · Medicare Code Editor v44.0 · NCCI PTP Q4 2026 · MUE Q4 2026 · NCD code lists 2026-01 · LCD export September 20, 2026 · All releases and sources