Granulomatosis with polyangiitis

Case contribution: Dr Radhiana Hassan

Clinical:

  • A 57 years old lady
  • Previously diagnosed Wagener granulomatosis (biopsy-proven) with lung involvement
  • Also had renal tubular acidosis and corticosteroid-induced osteoporosis
  • Latest presentation of progressive body weakness with reduced oral intake
  • The weakness is more on the right side
Non-contrast CT brain in axial plane soft tissue window
Axial and coronal CT scan in bone window
MPR Coronal CT brain in soft tissue window at different level

CT scan findings:

  • An area of hypodensity at left frontoparietal region
  • There are hyperintense foci within this hypodensity (yellow arrows)
  • Minimal mass effect and effacement of ipsilateral cerebral sulci
  • No midline shift
  • Presence of extraconal soft tissue density mass in the left orbital cavity (red arrow)
  • Abnormality also noted at paranasal sinuses with mucosal thickening and wall thickening (blue arrows)
MRI brain in axial plane; T1WI (first column), T2WI (second column), FLAIR (third column) and post contrast (fourth column)
CT scan brain in axial planes; T1, T2, FLAIR and T1+Gadolinium

 

MRI brain in axial plane DWI (upper row) and ADC (lower row) sequences

 

MRI brain in axial plane, hemo sequences
MRI brain in coronal plane, T2WI and post contrast images
MRI brain in sagittal plane; T1-weighted images (upper row) and T1+Gadolinium (lower row)

MRI findings:

  • There is restricted diffusion at left frontoparietal region.
  • Areas of T1-hyperintensity seen also at the same region (blue arrows)
  • There is abnormal vasogenic oedema of surrounding brain
  • Gyriform enhancement is seen at this region (green arrows)
  • Blooming artifacts are seen on hemo sequences (pink arrows)
  • All the paranasal sinuses shows mucosal thickening and fluid filled with heterogenous enhancement post contrast (red arrows)
  • Both globes are distorted. Enhancing lesion is seen in the right globe. Retro-orbital lesion is seen in the left side causing left proptosis (yellow arrows)
  • No significant finding on MRA and MRV (images not shown)

Diagnosis: Granulomatosis with polyangiitis: CNS, PNS and orbital manifestation

Discussion:

  • Granulomatosis with polyangiitis was previously known as Wagener granulomatosis.
  • It is a multisystem necrotizing non-caseating granulomatous vasculitis affecting small to medium-sized arteries, capillaries and veins with a predilection to respiratory system and kidneys.
  • There is slight male predilection and onset is typically at approximately 50 years of age.
  • Pulmonary manifestation: interstitial fibrosis at bases, multiple pulmonary nodules, cavitating nodule, pleural effusion and mediastinal nodes enlargement
  • Renal manifestation: either focal or diffuse lesion, focal glomerulonephritis
  • Upper respiratory tract and paranasal sinuses: mucosal ulceration and granulomatous masses within the nasal cavities with adjacent bony and cartilagenous destruction
  • Eyes and ears: proptosis and otitis media
  • Heart and pericardium : myocardial infarction
  • Skin : inflammatory skin lesion
  • Joints: migratory polyarthopathy
  • Spleen: may cause splenic infarction
  • CNS manifestation is rare and occurs in only about 5% of cases. Cerebral or meningeal granulomatous lesion include; hypertrophic pachymeningitis, small vessel CNS vasculitis causing infarcts and arterial occlusion, intracanial hemorhrage or continuous invasion of extracranial granuloma
Author: radhianahassan