Clinical features in two patients with IgA glomerulonephritis and thin-basement-membrane disease

Background. Both IgA glomerulonephritis (IgA gn) and thin basement membrane disease (TBMD) are common forms of glomerulonephritis. Patients with these conditions may present with identical clinical features, but higher urinary RBC counts, heavier proteinuria, and impaired renal function are more common in patients with IgA gn. Because IEA gn and TBMD are common, some patients will have both diseases. Subjects. We describe the clinical features of two individuals with both IgA gn and TBMD, and compare them with the clinical and laboratory characteristics in patients with TBMD (n = 15) or IEA gn (n = 32) alone. Results. ISA gn was found in two individuals of the 110 with TBMD who were studied. They both had haematuria with >/100 000 RBC/ml and proteinuria > 0.2/day (one had more than 1 g/day). These features were more consistent with IgA gn than TBMD alone. However, both individuals had normal serum creatinine and creatinine clearance at presentation. Additional clinical features were macroscopic haematuria in one and hypertension in both. Conclusions. IgA deposits are not uncommon in patients with TBMD, and these patients have clinical features that resemble those seen in IgA gn rather than TBMD. Patients with both ISA gn and TBMD do not necessarily have the worse prognosis noted in some patients with IgA gn.