a 71-year-old female
NSAID-induced secondary membranous nephropathy with acute kidney injury, from long-term unsupervised NSAID use for polymyalgia rheumatica
She reached clinical remission after she stopped the NSAID drug and was treated with intravenous methylprednisolone combined with rituximab. When she was accidentally given the NSAID again, the disease came back.
A 71-year-old woman's severe kidney damage was caused by long-term unsupervised NSAID painkiller use, not by primary kidney disease, and it improved once the drug was stopped and she was treated.
- A positive anti-PLA2R antibody test (hers was 39.69 U/mL) does not always mean primary membranous nephropathy, because it can also show up in drug-caused kidney disease.
- Her real cause was only found by a kidney biopsy taken during a relapse, which confirmed the NSAID painkiller was to blame.
- Stopping the NSAID plus treatment with intravenous methylprednisolone and rituximab brought her into clinical remission.
- Her disease came back after she was accidentally exposed to the NSAID again, which strongly points to the drug as the trigger.
- The biopsy showed extra clues (IgG1-predominant deposits, 2+ C1q staining, and severe interstitial nephritis) that helped separate drug-caused disease from the primary form.
Why it might work
The paper frames this as removing the cause. Her kidney filters were being damaged by a painkiller she took for a long time without medical supervision. Because the drug kept injuring the kidney, the damage continued as long as she kept taking it. Once the painkiller was stopped, the ongoing injury was removed, and the added medicines (a steroid, methylprednisolone, plus rituximab) helped calm the immune reaction in the kidney. The fact that her disease returned after she took the NSAID again is the clearest sign that the drug, not a primary kidney disease, was driving the harm.
The honest limits
- This is a single patient case (n=1), so it cannot tell us how often this happens or how well the same treatment works for others.
- The abstract does not give any after-treatment numbers, so we do not know her final albumin, creatinine, proteinuria, or antibody levels, only that she reached clinical remission.
- The cause of her first episode was unclear at the time and was only confirmed later by biopsy during a relapse.
- The abstract does not state any conflicts of interest or funding, so those are not disclosed here.
- Could any painkillers or other medicines I take regularly be harming my kidneys, and should I stop or change any of them?
- If my anti-PLA2R antibody test is positive, do I still need a kidney biopsy to rule out a drug-caused or secondary cause?
- Would IgG subclass testing and C1q staining on a biopsy help pin down the exact cause of my kidney disease?