M33.12: Other dermatomyositis with myopathy

M33.12, other dermatomyositis with myopathy, is listed as a covered diagnosis in 18 Medicare billing and coding articles that apply to 41 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…). 4 of these codes have a 2026 DMEPOS fee schedule amount; A7020 pays $19.87 to $23.81 (NU) depending on the state. 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 M33.12 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—7
J1561Injection, immune globulin, (gamunex-c/gammaked), non-lyophilized (e.g., liquid), 500 mgSpecial coverage instructions apply—7
J1459Injection, immune globulin (privigen), intravenous, non-lyophilized (e.g., liquid), 500 mgCarrier judgment—7
J1557Injection, immune globulin, (gammaplex), intravenous, non-lyophilized (e.g., liquid), 500 mgCarrier judgment—7
J1556Injection, immune globulin (bivigam), 500 mgCarrier judgment—7
J1568Injection, immune globulin, (octagam), intravenous, non-lyophilized (e.g., liquid), 500 mgCarrier judgment—7
J1566Injection, immune globulin, intravenous, lyophilized (e.g., powder), not otherwise specified, 500 mgSpecial coverage instructions apply—7
J1552Injection, immune globulin (alyglo), 500 mgCarrier judgment—6
J1554Injection, immune globulin (asceniv), 500 mgCarrier judgment—6
J1576Injection, immune globulin (panzyga), intravenous, non-lyophilized (e.g., liquid), 500 mgSpecial coverage instructions apply—5
J1577Injection, immune globulin (qivigy), 100 mgCarrier judgment—5
J1572Injection, immune globulin, (flebogamma/flebogamma dif), intravenous, non-lyophilized (e.g., liquid), 500 mgSpecial coverage instructions apply—4
J1553Injection, immune globulin (yimmugo), 100 mgCarrier judgment—3
J9312Injection, rituximab, 10 mgSpecial coverage instructions apply—4
Q5119Injection, rituximab-pvvr, biosimilar, (ruxience), 10 mgCarrier judgment—4
Q5115Injection, rituximab-abbs, biosimilar, (truxima), 10 mgSpecial coverage instructions apply—4
J1599Injection, immune globulin, intravenous, non-lyophilized (e.g., liquid), not otherwise specified, 500 mgCarrier judgment—4
J1575Injection, immune globulin/hyaluronidase, (hyqvia), 100 mg immuneglobulinCarrier judgment—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
A7020Interface for cough stimulating device, includes all components, replacement onlyCarrier judgment$19.87–$23.81 (NU)1
Q5123Injection, rituximab-arrx, biosimilar, (riabni), 10 mgCarrier judgment—3
E0483High frequency chest wall oscillation system, with full anterior and/or posterior thoracic region receiving simultaneous external oscillation, includes all accessories and supplies, eachCarrier judgment$1,515.12–$1,818.13 (RR)1

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

Medicare policy articles listing M33.12

3 more articles list M33.12.

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 M33.12 (Other dermatomyositis with myopathy)?

Medicare covers items and services, not diagnoses. 18 Medicare billing and coding articles list M33.12 as a covered diagnosis for 41 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 M33.12?

The Level II codes from the policies most specific to this diagnosis are J1569 (Injection, immune globulin, (gammagard liquid/gammagard…, 7 articles); J1561 (Injection, immune globulin, (gamunex-c/gammaked)…, 7 articles); J1459 (Injection, immune globulin (privigen), intravenous…, 7 articles); J1557 (Injection, immune globulin, (gammaplex), intravenous…, 7 articles); J1556 (Injection, immune globulin (bivigam), 500 mg, 7 articles). Code choice depends on the item supplied; check each code's descriptor.

What does Medicare pay for equipment billed with M33.12?

Under the 2026 DMEPOS fee schedule (non-rural state fees): A7020 $19.87 to $23.81 (NU); E0483 $1,515.12 to $1,818.13 (RR); A7025 $61.99 to $74.42 (RR); A7026 $40.96 to $49.15 (NU). Medicare pays 80% of the allowed amount after the Part B deductible.

Which Medicare policy articles list M33.12?

A58582 (Billing and Coding: Off-label Use of Rituximab and Rituximab Biosimilars); A52510 (Mechanical In-exsufflation Devices - Policy Article); A52494 (High Frequency Chest Wall Oscillation Devices - Policy Article), and 15 more articles.

What is ICD-10-CM code M33.12?

M33.12 is the ICD-10-CM code for other dermatomyositis with 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