[Lysozyme-induced nephropathy: A rare cause of renal failure in chronic myelomonocytic leukemia]

Introduction: Lysozyme-induced nephropathy is a rare and unknown complication of chronic myelomonocytic leukemia with overproduction of lysozyme by tumoral cells leading to proximal tubular cells injuries. The present case reports a lysozyme nephropathy secondary to chronic myelomonocytic leukemia.

Observation: We reported a case of a 82-years-old woman who presented an acute renal failure in a context of diarrhea and vomiting. Her background was characterized by untreated chronic myelomonocytic leukemia and high blood pressure. Despite rehydration, renal function deteriorated. Renal biopsy revealed a tubulo-interstitial lysozyme-induced nephropathy with a vacuolization of the tubular epithelium by eosinophilic droplets stained by anti-lysozyme antibody, without tumoral infiltration of the renal parenchyma.

Conclusion: Lysozyme-induced nephropathy is a rare disease which can be suspected biologically and needs histologic confirmation. Other causes of renal failure secondary to chronic myelomonocytic leukemia have to be eliminated first in these patients. The treatment is symptomatic and is associated with treatments of the underlying hematologic pathology.

Keywords: Chronic myelomonocytic leukemia; Insuffisance rénale; Leucémie myélomonocytaire chronique; Lysozyme; Renal failure.