Microscopic polyangitis presenting with temporal arteritis and multiple cranial neuropathies.

Area of Science:

• Rheumatology
• Neurology
• Nephrology

Background:

• Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) encompasses a group of systemic autoimmune diseases characterized by inflammation of small-to-medium-sized blood vessels.
• Neurological complications, including cranial neuropathies, can occur in AAV, but simultaneous large vessel involvement is less commonly reported.

Observation:

• A 77-year-old male presented with dysphagia, hoarseness, dysgeusia, gait instability, and temporal pain, alongside multiple cranial neuropathies.
• Investigations revealed elevated perinuclear ANCA, severe inflammation, mild proteinuria, and dural enhancement on brain MRI.
• Biopsies confirmed necrotizing glomerulonephritis and temporal arteritis without giant cells.

Findings:

• The patient was diagnosed with microscopic polyangiitis manifesting as temporal arteritis and cranial nerve involvement.
• Pathological confirmation of AAV lesions in both the temporal artery (large vessel) and the kidney (microvasculature) was established.
• Treatment with predonisolone led to symptom resolution and normalization of laboratory markers.

Implications:

• This case demonstrates that AAV can affect large arteries, such as the temporal artery, concurrently with microvasculature in organs like the kidney and nerves.
• It underscores the importance of considering AAV in patients presenting with cranial neuropathies and systemic inflammation, even with atypical large vessel involvement.
• The findings expand the understanding of the vascular distribution in AAV, suggesting a broader spectrum of potential organ system engagement.