[Proton pump inhibitor-induced nephrotoxicity]. / Nefrotoxiciteit van protonpompremmers.

Proton pump inhibitors are widely used, and generally considered safe. In this clinical lesson two cases are presented with a strong suspicion of proton pump inhibitor induced decline of kidney function. This adverse event has only recently been identified in epidemiological studies. Our cases illustrate that chronic proton pump inhibitor nephrotoxicity can manifest subtle and may therefore be difficult to recognize. We discuss the current epidemiological evidence to support these observations, and the pathophysiology and clinical manifestations of proton pump inhibitor nephrotoxicity. In case a subject using a proton pump inhibitor shows kidney function decline, without a clear cause, withdrawal of this medication is advised. Although for an individual patient the risk may not be high, the large number of proton pump users makes that this adverse event is important on a population level.

Nephrotic syndrome due to lupus-like glomerulonephritis in an HIV-positive patient.

Lupus nephritis, a well-known complication in systemic lupus erythematosus, is characterised by a proliferative glomerulonephritis or membranous nephropathy along with a full-house immunofluorescence pattern on renal biopsy. There are very few exceptions in which similar histopathological findings are present, but case reports show that an increasing number of HIV-positive patients (mostly black Africans, but also white patients) have HIV-immune complex disease (HIVICK), which can mimic lupus nephritis. Lupus-like HIVICK is treated differently than 'true' lupus nephritis, so distinction is warranted.