Concurrent Fabry disease and <scp>IgA</scp> nephropathy in a patient with Crohn's disease: A case report

We present a unique case of concurrent Fabry disease (FD) and IgA nephropathy (IgAN) in a 27-year-old female with a 10-year history of Crohn's disease (CD). The patient presented to the nephrology clinic with microscopic haematuria and proteinuria on routine tests. A kidney biopsy revealed mesangial matrix widening, mesangial cell proliferation, and podocyte enlargement with prominent lacy and clear cytoplasm, as observed with haematoxylin and eosin staining. Immunofluorescence staining demonstrated diffuse immunoglobulin A deposits in the mesangium. Electron microscopy identified myelin-like figures in the cytoplasm of podocytes and electron-dense deposits in the mesangium, confirming IgAN and suggesting FD. Subsequent testing showed low alpha-galactosidase A (α-gal) enzyme activity in the patient's white blood cells, confirming the FD diagnosis. Enzyme replacement therapy was initiated following the diagnosis. To our knowledge, this is the first reported case of the coexistence of FD, IgAN, and CD in a single patient. This case highlights the importance of considering FD in patients with proteinuria, emphasising the need for comprehensive diagnostic evaluations in complex cases.