Hairy kydneys unusual

Hairy kidney's sign is usualy discribe like a pathognomonic sign of Erdheim-Chester disease, rare, non-Langerhans cell histiocytosis. Case report: A 72-years-old men, kown for chronic myelomonocytic leukemia (CMML) JAK2 muted, presented an acute kidney failure, revealing un hairy kidney's sign at computed tomography. Kidney biopsy find an extramedullary hematopoeisis of CMML. We observed an improvement of the renal function with ruxolitinib. It was never been described until then. Conclusion: Hairy kidney's sign is usualy discribe like a pathognomonic sign of Erdheim-Chester disease, however, an extramedullary hematopoeisis of CMML, in this case, could be considered. In addition, this is the first reported case of a favorable therapeutic response to ruxolitinib in kidney infiltration of CMML.