An unexpected complication of chronic myelomonocytic leukemia: severe renal failure due to malignant tubulo-interstitial cell infiltration

A rare cause of acute kidney injury with chronic myelomonocytic leukemia

An 80-year-old man with myelodysplastic syndrome developed acute kidney injury (AKI) and peripheral blood monocyte-dominant leukocytosis. Glomerular disease was suspected from urinalysis, which showed proteinuria and microscopic hematuria with red cell casts. Eventually, he died of respiratory failure, after which a postmortem was performed. In the glomeruli, the extracapillary space was filled with numerous mononuclear cells and erythrocytes. At first interpretation, the glomerular findings appeared to represent cellular crescents. However, immunostaining revealed that the extracapillary mononuclear cells were in fact leukemic cells. Furthermore, tubular injury due to marked accumulation of lysozyme was also recognized together with infiltration of leukemic cells in the interstitium. The diagnosis of kidney infiltration by chronic myelomonocytic leukemia (CMML) and lysozyme-induced tubular injury was eventually made. Our case is the first report showing extracapillary infiltration of leukemic cells by immunostaining. In addition, lysozyme-induced tubular injury is a forgotten cause of kidney injury in patients with CMML. This case teaches us the rare and forgotten causes of AKI with CMML.

Successful treatment of a patient with Philadelphia chromosome-positive acute lymphoblastic leukemia complicated by bone marrow necrosis and acute renal insufficiency: A case report

Philadelphia chromosome (Ph)-positive acute lymphoblastic leukemia (ALL) complicated by bone marrow necrosis (BMN) and acute renal insufficiency (ARI) is rare in clinical practice. The aim of the present study was to summarize the clinical characteristics and treatment methods of a case of Ph⁺ ALL complicated by BMN and ARI. A 23-year-old male patient presented with pyrexia and a 2-month history of bone pain, and was diagnosed with Ph⁺ ALL complicated with BMN and ARI on peripheral blood tests, blood biochemistry tests, BM smear and fluorescence in situ hybridization. The patient underwent repeated hemodialysis, imatinib combination and maintenance chemotherapy, followed by allogeneic hematopoietic stem-cell transplantation. Some of the clinical signs and symptoms were alleviated, whereas others disappeared, and renal function was restored to normal. BM aspiration confirmed absence of necrosis and null lymphoblasts. Therefore, timely accurate diagnosis and effective treatment are crucial for patients with Ph⁺ ALL exhibiting potentially fatal complications.