M33.00Juvenile dermatomyositis, organ involvement unspecified

M33.00 is the ICD-10-CM diagnosis code for juvenile dermatomyositis, organ involvement unspecified. It belongs to category M33 (Dermatopolymyositis), block M30-M36 (systemic connective tissue disorders) and chapter 13 (diseases of the musculoskeletal system and connective tissue). It is billable, so it can be reported on its own for dates of service from October 1, 2026 through September 30, 2027.

Within M33.0, choose M33.00 (organ involvement unspecified) only when documentation doesn't support a more specific option: with respiratory involvement (M33.01), with myopathy (M33.02), without myopathy (M33.03) and with other organ involvement (M33.09).

As a secondary diagnosis it is a CC (complication or comorbidity), which can move an inpatient stay into the "with CC" MS-DRG of its family, unless the principal diagnosis excludes it.

In MS-DRG v44.0, it is part of the grouping logic for DRG 545 (Connective Tissue Disorders with MCC, relative weight 2.3892), DRG 546 (Connective Tissue Disorders with CC, relative weight 1.1745) and DRG 547 (Connective Tissue Disorders without CC/MCC, relative weight 0.7526), 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.

It has been part of ICD-10-CM since the code set took effect on October 1, 2015, and changed in FY2018 (title revised).

Before ICD-10, this condition was coded in ICD-9-CM as 710.3 (dermatomyositis).