Case of the week Details

B. LEGENDS

• Well-defined rounded lesions with central lucency and surrounding dense consolidation – “Atoll sign”. Diffuse peribronchovascular consolidations in left upper lobe and superior segment of right lower lobe.
• Patchy subpleural peripheral consolidation in superior and lateral basal segment of right lower lobe. Multiple ground glass centrilobular nodules scattered in all segments of bilateral lungs. Diffuse peribronchovascular wall and interstitial thickening.

Mucosal thickening in right maxillary & right sphenoid sinus.

DIAGNOSIS:

• Granulomatosis with polyangiitis. (GPA)

DISCUSSION:

• Main pulmonary manifestations of GPA.

*Reverse Halo Sign

Think organizing pneumonia first, but always exclude GPA, fungal infection, and pulmonary infarction.

*GGO + Hemorrhage

Think pulmonary capillaritis until proven otherwise

*GGO + Atoll Sign + Hemorrhage + Nodules/Cavities
GPA rises to the top of the differential

Diagnostic Criteria

The 2022 ACR/European Alliance of Associations for Rheumatology (EULAR) classification criteria for GPA includes the following weighted criteria:

• Bloody nasal discharge, nasal crusting, or sinonasal congestion (+3)
• Cartilaginous involvement (+2)
• Conductive or sensorineural hearing loss (+1)
• Cytoplasmic ANCA or anti-PR3 ANCA positivity (+5)
• Pulmonary nodules, mass, or cavitation on chest imaging (+2)
• Granuloma or giant cells on biopsy (+2)
• Inflammation or consolidation of the nasal/paranasal sinuses on imaging (+1)
• Pauci-immune glomerulonephritis (+1)
• Perinuclear ANCA or anti-MPO ANCA positivity (−1)
• Eosinophil count more than 1×10⁹ cells/L (−4)

After excluding mimics of vasculitis, a patient diagnosed with small- or medium-vessel vasculitis could be classified as having GPA if the cumulative score is 5 or more points.

MANAGEMENT

The treatment of GPA involves the use of immunosuppressive agents in a variety of combinations.
Treatment is classified into 2 phases:
The induction phase and The maintenance phase.

Commonly used agents are cyclophosphamide, glucocorticoids, rituximab, azathioprine, methotrexate, and plasmapheresis if indicated.

REFERENCES

Granulomatosis with polyangitis
Preeti Rout; Priyatha Garlapati; Ahmad Qurie.
https://www.ncbi.nlm.nih.gov/books/NBK557827/

From Head to Toe: Granulomatosis with Polyangiitis
Authors: From Head to Toe: Granulomatosis with Polyangiitis
Authors: Mahatma I. Guzman-Soto, MD
https://pubs.rsna.org/doi/abs/10.1148/rg.2021210132

Dr. DEEPTI H V
Senior Consultant Radiologist
Manipal Hospital, Yeshwanthpur, Bengaluru.

Dr SAMIR KUMAR
Radiology Resident
Manipal Hospital, Yeshwanthpur, Bengaluru.