M33.13: Other dermatomyositis without myopathy

M33.13, other dermatomyositis without myopathy, is listed as a covered diagnosis in 13 Medicare billing and coding articles that apply to 37 HCPCS Level II codes, including J1569 (Injection, immune globulin, (gammagard liquid/gammagard…), J1561 (Injection, immune globulin, (gamunex-c/gammaked)…), J1459 (Injection, immune globulin (privigen), intravenous…). The articles come from 7 Medicare contractors. A listed diagnosis supports medical necessity only; coverage still depends on the LCD's criteria and on documentation in the medical record.

HCPCS Level II codes with M33.13 as a covered diagnosis

CodeDescriptionMedicare coverageDMEPOS fee 2026 (state range)Articles listing it
J1569Injection, immune globulin, (gammagard liquid/gammagard liquid erc), 500 mgSpecial coverage instructions apply—5
J1561Injection, immune globulin, (gamunex-c/gammaked), non-lyophilized (e.g., liquid), 500 mgSpecial coverage instructions apply—5
J1459Injection, immune globulin (privigen), intravenous, non-lyophilized (e.g., liquid), 500 mgCarrier judgment—5
J1557Injection, immune globulin, (gammaplex), intravenous, non-lyophilized (e.g., liquid), 500 mgCarrier judgment—5
J1556Injection, immune globulin (bivigam), 500 mgCarrier judgment—5
J1568Injection, immune globulin, (octagam), intravenous, non-lyophilized (e.g., liquid), 500 mgCarrier judgment—5
J1566Injection, immune globulin, intravenous, lyophilized (e.g., powder), not otherwise specified, 500 mgSpecial coverage instructions apply—5
J1554Injection, immune globulin (asceniv), 500 mgCarrier judgment—5
J1576Injection, immune globulin (panzyga), intravenous, non-lyophilized (e.g., liquid), 500 mgSpecial coverage instructions apply—4
J1552Injection, immune globulin (alyglo), 500 mgCarrier judgment—4
J1577Injection, immune globulin (qivigy), 100 mgCarrier judgment—4
J1575Injection, immune globulin/hyaluronidase, (hyqvia), 100 mg immuneglobulinCarrier judgment—3
J1572Injection, immune globulin, (flebogamma/flebogamma dif), intravenous, non-lyophilized (e.g., liquid), 500 mgSpecial coverage instructions apply—3
J1559Injection, immune globulin (hizentra), 100 mgCarrier judgment—2
J1555Injection, immune globulin (cuvitru), 100 mgCarrier judgment—2
J1558Injection, immune globulin (xembify), 100 mgCarrier judgment—2
J1551Injection, immune globulin (cutaquig), 100 mgCarrier judgment—2
J1553Injection, immune globulin (yimmugo), 100 mgCarrier judgment—2
J1599Injection, immune globulin, intravenous, non-lyophilized (e.g., liquid), not otherwise specified, 500 mgCarrier judgment—3
J9312Injection, rituximab, 10 mgSpecial coverage instructions apply—3
Q5123Injection, rituximab-arrx, biosimilar, (riabni), 10 mgCarrier judgment—3
Q5119Injection, rituximab-pvvr, biosimilar, (ruxience), 10 mgCarrier judgment—3
Q5115Injection, rituximab-abbs, biosimilar, (truxima), 10 mgSpecial coverage instructions apply—3
J2791Injection, rho(d) immune globulin (human), (rhophylac), intramuscular or intravenous, 100 iuSpecial coverage instructions apply—1
J2792Injection, rho d immune globulin, intravenous, human, solvent detergent, 100 iuSpecial coverage instructions apply—1

12 more codes are listed. See every code with payment by region in Caduvo.

Medicare policy articles listing M33.13

A diagnosis listed as covered in a billing and coding article supports medical necessity for the article's codes; it does not guarantee payment. Coverage depends on the LCD's criteria, the contractor's jurisdiction and documentation in the medical record.

Other M33 diagnoses (Dermatopolymyositis)

Frequently asked questions

Does Medicare cover M33.13 (Other dermatomyositis without myopathy)?

Medicare covers items and services, not diagnoses. 13 Medicare billing and coding articles list M33.13 as a covered diagnosis for 37 HCPCS Level II codes: the diagnosis can support medical necessity for those codes, but payment still depends on the LCD's coverage criteria and the medical record.

Which HCPCS codes can be billed with ICD-10 M33.13?

The Level II codes from the policies most specific to this diagnosis are J1569 (Injection, immune globulin, (gammagard liquid/gammagard…, 5 articles); J1561 (Injection, immune globulin, (gamunex-c/gammaked)…, 5 articles); J1459 (Injection, immune globulin (privigen), intravenous…, 5 articles); J1557 (Injection, immune globulin, (gammaplex), intravenous…, 5 articles); J1556 (Injection, immune globulin (bivigam), 500 mg, 5 articles). Code choice depends on the item supplied; check each code's descriptor.

Which Medicare policy articles list M33.13?

A56786 (Billing and Coding: Immune Globulin); A57778 (Billing and Coding: Immune Globulin); A56718 (Billing and Coding: Intravenous Immunoglobulin (IVIG)), and 10 more articles.

What is ICD-10-CM code M33.13?

M33.13 is the ICD-10-CM code for other dermatomyositis without myopathy, in category M33 (Dermatopolymyositis), chapter 13: Diseases of the musculoskeletal system and connective tissue.

Next steps

Sources: CMS Medicare Coverage Database billing and coding articles (covered ICD-10 code lists and HCPCS links); ICD-10-CM FY2026; CMS HCPCS Level II release October 2026; CMS DMEPOS fee schedule 2026 (non-rural state fees). Not billing or legal advice.

Chapter 13: Diseases of the musculoskeletal system and connective tissue · All diagnoses · HCPCS lookup