Atypical Anti-Glomerular Basement Membrane Nephritis Occurring After SARS-CoV-2 Infection: A Case Report

Background: Atypical anti-glomerular basement membrane (GBM) disease, seronegative anti-GBM disease, is a variant where serum anti-GBM antibodies can not be identified in circulation although GBM is stained by Ig-G on an immunofluorescence microscope. We present a 19-year-old male patient who was previously healthy and developed the atypical anti-GBM disease after a SARS-CoV-2 infection. Case presentation The patient, who started to complain of hematuria and hemoptysis on the 3rd day of the negativity of the SARS-CoV-2 infection test, was referred to the hospital on the 15th day. The SerumAnti-GBM antibody of the patient who did not need hemodialysis was negative. Tubulointerstitial nephritis (TIN) was diagnosed in the kidney biopsy of the patient, and corticosteroid therapy was given. However, when the patient's complaints of hematuria and hemoptysis continued, a rebiopsy was performed. A diagnosis of atypical anti-GBM was made after linear IgG staining was detected in the glomerular basement membrane in the pathology of the patient whose serum anti-GBM antibodies were negative. Cyclophosphamide was given to the patient who was under corticosteroid treatment. Conclusion Although the classical anti-GBM disease is known to occur after SARS-CoV-2 infection, according to our knowledge, this case is the first case of atypical anti-GBM disease developed after SARS-CoV-2 infection.