M31.5: Giant cell arteritis with polymyalgia rheumatica
M31.5, giant cell arteritis with polymyalgia rheumatica, is listed as a covered diagnosis in 4 Medicare billing and coding articles that apply to 25 HCPCS Level II codes, including A9552 (Fluorodeoxyglucose f-18 fdg, diagnostic, per study dose…), A9598 (Positron emission tomography radiopharmaceutical…), A9601 (Flortaucipir f 18 injection, diagnostic, 1 millicurie). The articles come from 4 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 M31.5 as a covered diagnosis
| Code | Description | Medicare coverage | DMEPOS fee 2026 (state range) | Articles listing it |
|---|---|---|---|---|
| A9552 | Fluorodeoxyglucose f-18 fdg, diagnostic, per study dose, up to 45 millicuries | Carrier judgment | — | 1 |
| A9598 | Positron emission tomography radiopharmaceutical, diagnostic, for non-tumor identification, not otherwise classified | Carrier judgment | — | 1 |
| A9601 | Flortaucipir f 18 injection, diagnostic, 1 millicurie | 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 |
| J9260 | Injection, methotrexate sodium, 50 mg | Special coverage instructions apply | — | 1 |
| J9215 | Injection, interferon, alfa-n3, (human leukocyte derived), 250,000 iu | Special coverage instructions apply | — | 1 |
| C8900 | Magnetic resonance angiography with contrast, abdomen | Special coverage instructions apply | — | 1 |
| C8901 | Magnetic resonance angiography without contrast, abdomen | Special coverage instructions apply | — | 1 |
| C8902 | Magnetic resonance angiography without contrast followed by with contrast, abdomen | Special coverage instructions apply | — | 1 |
| C8909 | Magnetic resonance angiography with contrast, chest (excluding myocardium) | Special coverage instructions apply | — | 1 |
| C8910 | Magnetic resonance angiography without contrast, chest (excluding myocardium) | Special coverage instructions apply | — | 1 |
| C8911 | Magnetic resonance angiography without contrast followed by with contrast, chest (excluding myocardium) | Special coverage instructions apply | — | 1 |
| C8912 | Magnetic resonance angiography with contrast, lower extremity | Special coverage instructions apply | — | 1 |
| C8913 | Magnetic resonance angiography without contrast, lower extremity | Special coverage instructions apply | — | 1 |
| C8914 | Magnetic resonance angiography without contrast followed by with contrast, lower extremity | Special coverage instructions apply | — | 1 |
| C8918 | Magnetic resonance angiography with contrast, pelvis | Special coverage instructions apply | — | 1 |
| C8919 | Magnetic resonance angiography without contrast, pelvis | Special coverage instructions apply | — | 1 |
| C8920 | Magnetic resonance angiography without contrast followed by with contrast, pelvis | Special coverage instructions apply | — | 1 |
| G0278 | Iliac and/or femoral artery angiography, non-selective, bilateral or ipsilateral to catheter insertion, performed at the same time as cardiac catheterization and/or coronary angiography, includes positioning or placement of the catheter in the distal aorta or ipsilateral femoral or iliac artery, injection of dye, production of permanent images, and radiologic supervision and interpretation (list separately in addition to primary procedure) | Carrier judgment | — | 1 |
| G0219 | Pet imaging whole body; melanoma for non-covered indications | Non-covered by Medicare | Not covered | 1 |
| G0235 | Pet imaging, any site, not otherwise specified | Non-covered by Medicare | Not covered | 1 |
| G0252 | Pet imaging, full and partial-ring pet scanners only, for initial diagnosis of breast cancer and/or surgical planning for breast cancer (e.g., initial staging of axillary lymph nodes) | Non-covered by Medicare | Not covered | 1 |
Medicare policy articles listing M31.5
- A59318: Billing and Coding: Positron Emission Tomography (PET) Scan for Inflammation and Infection (CGS Administrators, LLC (MAC - Part A, MAC - Part B); 6 Level II codes). LCD with the same title: L39521
- A55639: Billing and Coding: Chemotherapy Agents for Non-Oncologic Conditions (WPS Insurance Corporation (MAC - Part A, MAC - Part B); 6 Level II codes)
- A56805: Billing and Coding: Magnetic Resonance Angiography (MRA) (Novitas Solutions, Inc. (MAC - Part A, MAC - Part B); 12 Level II codes). LCD with the same title: L33633, L34372, L34865
- A57056: Billing and Coding: Aortography and Peripheral Angiography (First Coast Service Options, Inc. (MAC - Part A, MAC - Part B); 1 Level II codes). LCD with the same title: L36767
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 M31 diagnoses (Other necrotizing vasculopathies)
- M31.11 — Hematopoietic stem cell transplantation-associated thrombotic…
- M31.19 — Other thrombotic microangiopathy
- M31.30 — Wegener's granulomatosis without renal involvement
- M31.31 — Wegener's granulomatosis with renal involvement
- M31.4 — Aortic arch syndrome [Takayasu]
- M31.6 — Other giant cell arteritis
- M31.7 — Microscopic polyangiitis
Frequently asked questions
Does Medicare cover M31.5 (Giant cell arteritis with polymyalgia rheumatica)?
Medicare covers items and services, not diagnoses. 4 Medicare billing and coding articles list M31.5 as a covered diagnosis for 25 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 M31.5?
The Level II codes from the policies most specific to this diagnosis are A9552 (Fluorodeoxyglucose f-18 fdg, diagnostic, per study dose…, 1 article); A9598 (Positron emission tomography radiopharmaceutical…, 1 article); A9601 (Flortaucipir f 18 injection, diagnostic, 1 millicurie, 1 article); J9312 (Injection, rituximab, 10 mg, 1 article); Q5123 (Injection, rituximab-arrx, biosimilar, (riabni), 10 mg, 1 article). Code choice depends on the item supplied; check each code's descriptor.
Which Medicare policy articles list M31.5?
A59318 (Billing and Coding: Positron Emission Tomography (PET) Scan for Inflammation and Infection); A55639 (Billing and Coding: Chemotherapy Agents for Non-Oncologic Conditions); A56805 (Billing and Coding: Magnetic Resonance Angiography (MRA)), and 1 more article.
What is ICD-10-CM code M31.5?
M31.5 is the ICD-10-CM code for giant cell arteritis with polymyalgia rheumatica, in category M31 (Other necrotizing vasculopathies), chapter 13: Diseases of the musculoskeletal system and connective tissue.
Next steps
- Run a reimbursement report for a device billed under A9552
- Watch A9552 for fee, coverage and descriptor changes
- Build a full Medicare revenue model for A9552
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