Immunoglobulin A Nephropathy, Celiac Disease, and Immune Complex Pneumonitis: A Rare Case Report of an Immunoglobulin A-Associated Pathologic Trifecta.

INTRODUCTION: The systemic manifestations of immunoglobulin A (IgA) nephropathy with lung involvement include diffuse alveolar hemorrhage due to monoclonal IgA disorders, IgA-variant Good pasture's syndrome, and Henoch-Schoenlein purpura. However, pneumonitis due to IgA immune complex has rarely been reported as the pulmonary manifestations of IgA nephropathy. CASE
PRESENTATION: A 35-year-old woman presented with 2 years of progressive shortness of breath, dry cough, low-grade fever along with progressive loss of appetite, and loss of weight. She underwent renal, duodenal, and lung biopsies. She was diagnosed with a rare combination of IgA-mediated nephropathy, IgA-associated celiac disease, and IgA-mediated immune complex cavitary lung disease. DISCUSSION: Secretory IgA may be acting as an immune complex or proinflammatory agent to provoke the signs and symptoms in this case. Thus, the respiratory process may incite renal disease or vice-versa. Further research is needed to analyze the possibility of such associations.