MS-DRGs in MDC 18
Weights in this category range from 0.6780 (DRG 869) to 6.9430 (DRG 870); the change column compares FY2027 with FY2026.
| DRG | Title | Type | Weight | GMLOS | Change |
|---|---|---|---|---|---|
| 853 | Infectious and Parasitic Diseases with O.R. Procedures with MCC | Surgical | 4.9310 | 9.2 | -0.2% |
| 854 | Infectious and Parasitic Diseases with O.R. Procedures with CC | Surgical | 2.0090 | 4.8 | +0.6% |
| 855 | Infectious and Parasitic Diseases with O.R. Procedures without CC/MCC | Surgical | 1.4500 | 3.2 | -3.1% |
| 856 | Postoperative or Post-Traumatic Infections with O.R. Procedures with MCC | Surgical | 4.4820 | 8.8 | -1.5% |
| 857 | Postoperative or Post-Traumatic Infections with O.R. Procedures with CC | Surgical | 2.1680 | 5.3 | +1.2% |
| 858 | Postoperative or Post-Traumatic Infections with O.R. Procedures without CC/MCC | Surgical | 1.4030 | 3.3 | +0.7% |
| 862 | Postoperative and Post-Traumatic Infections with MCC | Medical | 1.7910 | 4.9 | -1.8% |
| 863 | Postoperative and Post-Traumatic Infections without MCC | Medical | 0.9870 | 3.3 | -1.1% |
| 864 | Fever and Inflammatory Conditions | Medical | 0.8550 | 2.5 | -3.7% |
| 865 | Viral Illness with MCC | Medical | 1.3490 | 3.7 | -10.0% |
| 866 | Viral Illness without MCC | Medical | 0.8690 | 2.7 | -0.1% |
| 867 | Other Infectious and Parasitic Diseases Diagnoses with MCC | Medical | 2.1860 | 5.3 | +4.4% |
| 868 | Other Infectious and Parasitic Diseases Diagnoses with CC | Medical | 1.0230 | 3.3 | -0.8% |
| 869 | Other Infectious and Parasitic Diseases Diagnoses without CC/MCC | Medical | 0.6780 | 2.4 | -7.1% |
| 870 | Septicemia or Severe Sepsis with MV >96 Hours | Medical | 6.9430 | 12.5 | +0.5% |
| 871 | Septicemia or Severe Sepsis without MV >96 Hours with MCC | Medical | 1.9320 | 4.8 | -0.5% |
| 872 | Septicemia or Severe Sepsis without MV >96 Hours without MCC | Medical | 1.0070 | 3.4 | -1.6% |
How to read this table
The relative weight is the payment multiplier CMS applies to a hospital's wage-adjusted standardized amount; a weight of 2.0 pays roughly twice an average inpatient case before outliers and add-ons. Geometric mean length of stay is the figure used in post-acute transfer calculations, so stays shorter than it in a transfer DRG are paid per diem. The change column compares the FY2027 final weight with FY2026; moves larger than two percent usually come from code reassignments in the final rule's Table 6 series or from updated cost data, and are worth re-checking in contract models and budgets before October 1. Surgical DRGs require a qualifying operating-room procedure; medical DRGs are reached when no such procedure is coded.
Frequently asked questions
How many MS-DRGs are in MDC 18?
17 MS-DRGs are assigned to MDC 18 (Infectious and Parasitic Diseases, Systemic or Unspecified Sites) in the FY2027 v44 grouper: 6 surgical and 11 medical.
Which MDC 18 DRG has the highest weight?
DRG 870, Septicemia or Severe Sepsis with MV >96 Hours, carries the highest FY2027 relative weight in this category at 6.9430; the lowest is DRG 869 at 0.6780.
How is a stay assigned to this MDC?
The grouper maps the principal diagnosis to MDC 18, then checks for a qualifying operating-room procedure to choose between the surgical and medical DRG partitions, and finally applies CC/MCC severity splits.
Sources
Every figure on this page is taken from the CMS publications below, as released by the Centers for Medicare & Medicaid Services. Projection built 2026-10-01. Verify against the primary file before billing or contracting decisions.
- IPPS FY2027 Final Rule Table 5 (CMS-1849-F)Version v44 FY2027 · effective 2026-10-01 · file CMS-1849-F Table 5.txtSHA-256 01003dd571c1e2f5…
- IPPS FY2026 Final Rule Table 5 (CMS-1833-F)Version v43 FY2026 · effective 2025-10-01 · file CMS-1833-F Table 5.txtSHA-256 bf8c390d14b3cd3e…
Disclaimer
Operational reference compiled from CMS publications. Relative weights are national factors; actual payment depends on hospital-specific rates and adjustments. Not legal, clinical or billing advice.