M33.91: Dermatopolymyositis, unspecified with respiratory involvement
M33.91, dermatopolymyositis, unspecified with respiratory involvement, is listed as a covered diagnosis in 12 Medicare billing and coding articles that apply to 32 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 5 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 M33.91 as a covered diagnosis
| Code | Description | Medicare coverage | DMEPOS fee 2026 (state range) | Articles listing it |
|---|---|---|---|---|
| J1569 | Injection, immune globulin, (gammagard liquid/gammagard liquid erc), 500 mg | Special coverage instructions apply | — | 5 |
| J1561 | Injection, immune globulin, (gamunex-c/gammaked), non-lyophilized (e.g., liquid), 500 mg | Special coverage instructions apply | — | 5 |
| J1459 | Injection, immune globulin (privigen), intravenous, non-lyophilized (e.g., liquid), 500 mg | Carrier judgment | — | 5 |
| J1557 | Injection, immune globulin, (gammaplex), intravenous, non-lyophilized (e.g., liquid), 500 mg | Carrier judgment | — | 5 |
| J1556 | Injection, immune globulin (bivigam), 500 mg | Carrier judgment | — | 5 |
| J1568 | Injection, immune globulin, (octagam), intravenous, non-lyophilized (e.g., liquid), 500 mg | Carrier judgment | — | 5 |
| J1566 | Injection, immune globulin, intravenous, lyophilized (e.g., powder), not otherwise specified, 500 mg | Special coverage instructions apply | — | 5 |
| J1552 | Injection, immune globulin (alyglo), 500 mg | Carrier judgment | — | 4 |
| J1554 | Injection, immune globulin (asceniv), 500 mg | Carrier judgment | — | 4 |
| J1599 | Injection, immune globulin, intravenous, non-lyophilized (e.g., liquid), not otherwise specified, 500 mg | Carrier judgment | — | 4 |
| J1576 | Injection, immune globulin (panzyga), intravenous, non-lyophilized (e.g., liquid), 500 mg | Special coverage instructions apply | — | 3 |
| J1577 | Injection, immune globulin (qivigy), 100 mg | Carrier judgment | — | 3 |
| J1572 | Injection, immune globulin, (flebogamma/flebogamma dif), intravenous, non-lyophilized (e.g., liquid), 500 mg | Special coverage instructions apply | — | 2 |
| J1553 | Injection, immune globulin (yimmugo), 100 mg | Carrier judgment | — | 1 |
| J2791 | Injection, rho(d) immune globulin (human), (rhophylac), intramuscular or intravenous, 100 iu | Special coverage instructions apply | — | 1 |
| J2792 | Injection, rho d immune globulin, intravenous, human, solvent detergent, 100 iu | Special coverage instructions apply | — | 1 |
| G0238 | Therapeutic procedures to improve respiratory function, other than described by g0237, one on one, face to face, per 15 minutes (includes monitoring) | Carrier judgment | — | 1 |
| G0237 | Therapeutic procedures to increase strength or endurance of respiratory muscles, face to face, one on one, each 15 minutes (includes monitoring) | Carrier judgment | — | 1 |
| G0239 | Therapeutic procedures to improve respiratory function or increase strength or endurance of respiratory muscles, two or more individuals (includes monitoring) | Carrier judgment | — | 1 |
| J9312 | Injection, rituximab, 10 mg | Special coverage instructions apply | — | 1 |
| Q5123 | Injection, rituximab-arrx, biosimilar, (riabni), 10 mg | Carrier judgment | — | 1 |
| Q5119 | Injection, rituximab-pvvr, biosimilar, (ruxience), 10 mg | Carrier judgment | — | 1 |
| Q5115 | Injection, rituximab-abbs, biosimilar, (truxima), 10 mg | Special coverage instructions apply | — | 1 |
| J1575 | Injection, immune globulin/hyaluronidase, (hyqvia), 100 mg immuneglobulin | Carrier judgment | — | 1 |
| J1460 | Injection, gamma globulin, intramuscular, 1 cc | Special coverage instructions apply | — | 1 |
7 more codes are listed. See every code with payment by region in Caduvo.
Medicare policy articles listing M33.91
- A57187: Billing and Coding: Immune Globulin Intravenous (IVIg) (Noridian Healthcare Solutions, LLC (MAC - Part A, MAC - Part B); 13 Level II codes). LCD with the same title: L34314
- A56779: Billing and Coding: Intravenous Immune Globulin (CGS Administrators, LLC (MAC - Part A, MAC - Part B); 9 Level II codes). LCD with the same title: L33610, L35891
- A56718: Billing and Coding: Intravenous Immunoglobulin (IVIG) (Palmetto GBA (MAC - Part A, MAC - Part B); 13 Level II codes). LCD with the same title: L34580
- A59105: Billing and Coding: Off-Label Use of Intravenous Immune Globulin (IVIG) (Wellpoint Federal (MAC - Part A, MAC - Part B); 11 Level II codes). LCD with the same title: L39314
- A56717: Billing and Coding: Respiratory Therapy (Respiratory Care) (Palmetto GBA (MAC - Part A); 3 Level II codes). LCD with the same title: L34430
- A59101: Billing and Coding: Off-label Use of Rituximab and Rituximab Biosimilars (Wellpoint Federal (MAC - Part A, MAC - Part B); 4 Level II codes). LCD with the same title: L38920, L39297
- A57307: Billing and Coding: Nerve Conduction Studies and Electromyography (CGS Administrators, LLC (MAC - Part A, MAC - Part B); 1 Level II codes). LCD with the same title: L34594, L34859, L35048, L35081
- A57478: Billing and Coding: Nerve Conduction Studies and Electromyography (WPS Insurance Corporation (MAC - Part A, MAC - Part B); 1 Level II codes). LCD with the same title: L34594, L34859, L35048, L35081
- A57554: Billing and Coding: Immune Globulins (WPS Insurance Corporation (MAC - Part A, MAC - Part B); 20 Level II codes). LCD with the same title: L34771
- A54969: Billing and Coding: Nerve Conduction Studies and Electromyography (Noridian Healthcare Solutions, LLC (MAC - Part A, MAC - Part B); 1 Level II codes). LCD with the same title: L34594, L34859, L35048, L35081
- A57668: Billing and Coding: Nerve Conduction Studies and Electromyography (Wellpoint Federal (MAC - Part A, MAC - Part B); 1 Level II codes). LCD with the same title: L34594, L34859, L35048, L35081
- A56619: Billing and Coding: Nerve Conduction Studies and Electromyography (Palmetto GBA (MAC - Part A, MAC - Part B); 1 Level II codes). LCD with the same title: L34594, L34859, L35048, L35081
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)
- M33.90 — Dermatopolymyositis, unspecified, organ involvement unspecified
- M33.92 — Dermatopolymyositis, unspecified with myopathy
- M33.93 — Dermatopolymyositis, unspecified without myopathy
- M33.99 — Dermatopolymyositis, unspecified with other organ involvement
- M33.00 — Juvenile dermatomyositis, organ involvement unspecified
- M33.01 — Juvenile dermatomyositis with respiratory involvement
- M33.02 — Juvenile dermatomyositis with myopathy
- M33.03 — Juvenile dermatomyositis without myopathy
- M33.09 — Juvenile dermatomyositis with other organ involvement
- M33.10 — Other dermatomyositis, organ involvement unspecified
- M33.11 — Other dermatomyositis with respiratory involvement
- M33.12 — Other dermatomyositis with myopathy
- M33.13 — Other dermatomyositis without myopathy
- M33.19 — Other dermatomyositis with other organ involvement
- M33.20 — Polymyositis, organ involvement unspecified
- M33.21 — Polymyositis with respiratory involvement
- M33.22 — Polymyositis with myopathy
- M33.29 — Polymyositis with other organ involvement
Frequently asked questions
Does Medicare cover M33.91 (Dermatopolymyositis, unspecified with respiratory…)?
Medicare covers items and services, not diagnoses. 12 Medicare billing and coding articles list M33.91 as a covered diagnosis for 32 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 M33.91?
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 M33.91?
A57187 (Billing and Coding: Immune Globulin Intravenous (IVIg)); A56779 (Billing and Coding: Intravenous Immune Globulin); A56718 (Billing and Coding: Intravenous Immunoglobulin (IVIG)), and 9 more articles.
What is ICD-10-CM code M33.91?
M33.91 is the ICD-10-CM code for dermatopolymyositis, unspecified with respiratory involvement, in category M33 (Dermatopolymyositis), chapter 13: Diseases of the musculoskeletal system and connective tissue.
Next steps
- Run a reimbursement report for a device billed under J1569
- Watch J1569 for fee, coverage and descriptor changes
- Build a full Medicare revenue model for J1569
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