ICD-10-CM 2027
ICD-10 code for diffuse eosinophilic fasciitis
From the official ICD-10-CM alphabetic index entry “Fasciitis › diffuse (eosinophilic)”. Page updated September 29, 2026.
About coding diffuse eosinophilic fasciitis
The ICD-10-CM code for diffuse eosinophilic fasciitis is M35.4 (Diffuse (eosinophilic) fasciitis).
Within M35 (other systemic involvement of connective tissue), M35.4 is specifically for diffuse (eosinophilic) fasciitis. Related codes cover Sjogren syndrome (M35.0), other overlap syndromes (M35.1), Behcet's disease (M35.2), polymyalgia rheumatica (M35.3), multifocal fibrosclerosis (M35.5), relapsing panniculitis [Weber-Christian] (M35.6), hypermobility syndrome (M35.7), other specified systemic involvement of connective tissue (M35.8) and 1 more.
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 557 (Tendonitis, Myositis and Bursitis with MCC, relative weight 1.489) and DRG 558 (Tendonitis, Myositis and Bursitis without MCC, relative weight 0.8875), in MDC 08 (Diseases and Disorders of the Musculoskeletal System and Connective Tissue), 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 diffuse eosinophilic fasciitis ICD-10 codes
What is the ICD-10 code for diffuse eosinophilic fasciitis?
- M35.4 — Diffuse (eosinophilic) fasciitis.
Is M35.4 billable?
- Yes. M35.4 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can M35.4 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict M35.4 as a principal diagnosis.
Is M35.4 a CC or MCC?
- No. M35.4 is neither a CC nor an MCC under MS-DRG v44.0.