Microscopic polyangiitis complicated with bilateral brachial plexopathy: a case report and review of the literature

Area of Science:

• Rheumatology
• Neurology
• Pulmonology

Background:

• Microscopic polyangiitis (MPA) is a small-vessel vasculitis often associated with anti-neutrophil cytoplasmic antibodies (ANCA).
• MPA commonly affects the kidneys (glomerulonephritis) and lungs (hemorrhagic capillaritis).
• Peripheral nervous system involvement is recognized in ANCA-associated vasculitis, though brachial plexopathy is rare.

Observation:

• A 22-year-old male with diagnosed MPA on maintenance therapy presented with worsening cough, dyspnea, and hemoptysis.
• He also developed upper limb pain, paresthesia, hypoesthesia, absent reflexes, and decreased muscle strength.
• Chest CT revealed ground glass opacities, and electrodiagnostic studies confirmed bilateral brachial plexopathy.

Findings:

• The patient exhibited pulmonary symptoms consistent with MPA flare.
• Neurological examination and electrodiagnostic studies revealed significant bilateral brachial plexopathy.
• The brachial plexopathy involved all cervical roots, with greater severity on the left and lower roots.

Implications:

• This case underscores the potential for MPA to manifest with diverse and unusual neurological complications.
• Early recognition of brachial plexopathy in MPA patients is crucial for timely diagnosis and management.
• Further research may elucidate the specific mechanisms linking MPA to brachial plexopathy.