Atypical Presentation of Microscopic Polyangiitis with Pericarditis Manifesting as Right-Sided Heart Failure

Area of Science:

• Nephrology
• Cardiology
• Rheumatology

Background:

• Microscopic polyangiitis (MPA) is a systemic vasculitis associated with anti-neutrophil cytoplasmic antibodies (ANCA).
• Cardiac involvement is an uncommon complication of MPA.
• MPA typically affects the kidneys and lungs.

Purpose of the Study:

• To report a rare case of MPA presenting with cardiac complications.
• To highlight atypical initial manifestations of MPA.

Main Methods:

• Case report of a patient with MPA.
• Clinical presentation analysis including peripheral edema, weight gain, and echocardiography findings.
• Laboratory tests including myeloperoxidase-ANCA (MPO-ANCA) assessment.
• Renal biopsy for histopathological examination.

Main Results:

• The patient presented with acute pericarditis, borderline cardiac tamponade, and right-sided heart failure.
• Strongly positive MPO-ANCA confirmed MPA.
• Renal biopsy showed pauci-immune crescentic glomerulonephritis, consistent with MPA.
• Pericarditis with compressive syndrome was the initial manifestation.

Conclusions:

• MPA can present atypically with pericarditis and cardiac compromise.
• Early recognition of cardiac involvement is crucial in MPA diagnosis.
• This case expands the spectrum of MPA initial presentations.