IgA Nephropathy Coexisting with Linear IgA Bullous Disease
Dear Editor,
Linear IgA bullous disease (LABD) is a rare autoimmune subepidermal bullous disease with different clinical manifestations, characterized by linear deposition of IgA in epidermal basement membrane zone.Citation1 An increased incidence of glomerulonephritis has been reported in patients with autoimmune bullous disease. Here, we report a patient with LABD developing IgA nephropathy (IgAN).
A 28-year-old male was hospitalized for evaluation of macroscopic hematuria and lumbar pain. He has been followed with a diagnosis of LABD for 6 months and his skin symptoms were under control with oral prednisolone 12.5 mg/day therapy. Physical examination of patient was normal, except for brownish hyperpigmentation in recovering skin lesion. The laboratory examinations revealed the presence of proteinuria (985 mg/day), normal renal function (creatinine 88 µmol/L, BUN 5.1 mmol/L), total serum protein 70 g/L, and serum albumin 40 g/L. There were +3 erythrocytes and no cast on urine analysis. Liver function tests were normal. The anti-neutrophil cytoplasmic autoantibody (ANCA) antibodies, anti-neclear antibodies (ANA), anti-dsDNA, the serum complement, and the IgG, IgM, IgA values were within normal limits. Viral serology for HIV, hepatitis B and C were negative. Sonogram of the kidney was normal.
Percutaneous kidney biopsy was performed due to persistent hematuria and proteinuria, and in total 19 glomeruli were obtained and evaluated. Four glomeruli had crescentic formation, and diffuse mesangial proliferation and expanded matrix were observed in the remaining glomeruli by light microscopy. Immunohistochemical staining showed mesangial deposition of 2+ diffuse IgA and, to a much less extent, C3. Staining for amyloidosis was negative. The diagnosis of IgAN was made based on light and immunofluorescence microscopic assessment. His steroid therapy was continued for LABD, but not for IgAN.
IgAN is the most common cause of glomerulonephritis in adult and is characterized by mesangial proliferation and deposition of IgA.Citation2 Secondary IgAN may be associated with several immunological skin diseases such as dermatitis herpetiformis, epidermolysis bullosa, bullous pemphigoid, and LABD. IgAN associated with LABD has been rarely reported so far. In 1995, Pena-Penabad et al. reported IgAN in a 31-year-old woman presenting LABD, who also had autoimmune hemolytic anemia. The other was described in a 16‐year-old girl.Citation3,Citation4 We present a case of IgAN coexisting with LABD.
A relationship between LABD and IgAN is still unclear. Immunopathologically, IgA antibodies have been reported to react with numerous basement membrane antigens in idiopathic LABD.Citation5 These autoimmune phenomena may induce both cellular and humoral immune response with immune complex deposition. Induction of IgA synthesis to autoantigens might explain the presence of IgA in an epidermal basement membrane and glomerular mesangium.
In conclusion, it is important for clinicians to be aware of this novel combination to follow up patients with LABD closely, particularly searching for evidence of renal disease. Therefore, we recommend that urinalysis must be performed annually to detect hematuria and proteinuria in patients with LABD.
References
- Van der Waal RI, van de Scheur MR, Pas HH, Linear IgA bullous dermatosis in a patient with renal cell carcinoma. Br J Dermatol. 2001;144:870–873.
- Wen YK, Chen ML. The spectrum of acute renal failure in IgA nephropathy. Ren Fail. 2010;32:428–433.
- Rositto AE, Cobeñas C, Drut R. Linear IgA disease of childhood developing IgA nephropathy. Pediatr Dermatol. 2008;25: 339–340.
- Pena-Penabad C, Hernández-Vicente I, Hernández-Martín A, IgA mesangial nephropathy and autoimmune hemolytic anaemia associated with linear IgA bullous dermatosis. Br J Dermatol. 1995;133:146–148.
- Eisendle K, Bonatti H, Sepp N, Höpfl R. Vancomycin-induced linear IgA bullous dermatosis in an immunosuppressed transplant recipient. J Eur Acad Dermatol Venereol. 2007;21:996–997.