K35-K38 — Diseases of appendix
Every ICD-10-CM code in this range and the PDGM clinical group CMS assigns to it, read from the CMS grouper crosswalk v07.1.26.
Codes in range
21
No clinical group
1
A period cannot be grouped from these.
Barred as primary
0
CMS rejects these in the primary position.
Where these codes group
17 of the 21 codes in K35-K38 group to MMTA - Gastrointestinal tract and Genitourinary system, but the range is not uniform — it spreads across 2 clinical groups. A further 1 are assigned no clinical group at all, which means a 30-day period cannot be grouped from them.
Every code in K35-K38
Descriptions are CMS’s own, abbreviated as CMS abbreviates them.
| Code | Description | Clinical group | Primary position |
|---|---|---|---|
| K35200 | Acute appendicitis with gen peritonitis, w/o perf or abscs | J | Accepted |
| K35201 | Ac appendicitis with gen peritonitis, with perf, w/o abscs | J | Accepted |
| K35209 | Ac appendicitis w gen peritonitis,w/o abscs,unsp as to perf | J | Accepted |
| K35210 | Ac appendicitis with gen peritonitis, w/o perf, with abscs | J | Accepted |
| K35211 | Acute appendicitis with gen peritonitis, with perf and abscs | J | Accepted |
| K35219 | Ac appendicitis w gen peritonitis, w abscs, unsp as to perf | J | Accepted |
| K3530 | Acute appendicitis with loc peritonitis, w/o perf or gangr | J | Accepted |
| K3531 | Acute appendicitis with loc peritonitis and gangr, w/o perf | J | Accepted |
| K3532 | Ac appendicitis w perf, loc peritonitis, & gangr, w/o abscs | J | Accepted |
| K3533 | Ac appendicitis with perf, loc peritonitis, and gangr, wbscs | J | Accepted |
| K3580 | Unspecified acute appendicitis | J | Accepted |
| K35890 | Other acute appendicitis without perforation or gangrene | J | Accepted |
| K35891 | Other acute appendicitis without perforation, with gangrene | J | Accepted |
| K36 | Other appendicitis | J | Accepted |
| K37 | Unspecified appendicitis | J | Accepted |
| K380 | Hyperplasia of appendix | J | Accepted |
| K381 | Appendicular concretions | A | Accepted |
| K382 | Diverticulum of appendix | A | Accepted |
| K383 | Fistula of appendix | A | Accepted |
| K388 | Other specified diseases of appendix | J | Accepted |
| K389 | Disease of appendix, unspecified | None | Cannot group |
Source: CMS HH PPS Grouper Software v07.1.26, effective 2026-04-01. This is the crosswalk Medicare runs a claim through. Grouping also depends on admission source, timing, the OASIS functional items and the rest of the diagnosis list.
The monthly home health regs digest
What CMS changed, what's due next, and what to do about it — one email a month, no fluff.