We present a 61-year-old male with FLT3-mutated acute myeloid leukemia treated with midostaurin who developed acute kidney injury requiring hemodialysis and pulmonary renal syndrome. cannot be excluded when faced with bad serologies. We present a unique case of hardly ever reported ANCA-negative necrotizing pauci-immune GN-associated pulmonary renal syndrome (PRS) and its first reported association with midostaurin. Case statement A 61-year-old male with relapsed FLT3-mutated acute myeloid leukemia (AML) offered to the emergency division (ED) with chest pain, cough, diarrhea, and occasional syncope. He was recently treated for relapsed AML with IV decitabine 20?mg/m2 for 10?days, venetoclax 200?mg daily for 14?days and midostaurin 50? mg twice daily. Three days after discharge, he arrived to the ED with hypotension, which improved with IV fluids. He was pancytopenic on introduction having a platelet count of 36?K/L, white blood cell count of 1 1.2?K/L, and hemoglobin of 8.4?g/dL. He quickly developed hemoptysis and microscopic hematuria. Chest X-ray and non-contrast computed tomography (CT) imaging of his chest, stomach, and pelvis exposed considerable bilateral pulmonary infiltrates concerning for multifocal pneumonia versus DAH and was treated with empiric broad spectrum antibiotics. However, Roy-Bz bronchoscopy performed showed the presence of blood in the BAL. No pulmonary biopsy was carried out. An esophagogastroduodenoscopy (EGD) exposed no active bleeding. He required many platelet transfusions throughout his hospitalization due to significant thrombocytopenia. He had refused any prior history of hypertension or renal dysfunction. He had history of nephrolithiasis and prostate malignancy, which never required treatment. His analysis of AML was Roy-Bz 10?years prior to demonstration and was treated with intensive therapy and achieved remission which sustained until a 12 months prior to current check out. His baseline creatinine was 0.76?mg/dL, measured a week prior to demonstration. No urinary evaluation was required prior to the current demonstration. Upon arrival to the ED, his creatinine was 1.90?mg/dL which improved to 1 1.06?mg/dL with IV fluids but increased to 2.55?mg/dL within a week of hospitalization, prompting Nephrology discussion. Urinalysis revealed more than 182 reddish blood cells (RBC)/high power field (HPF), 219 hyaline solid. Urinary protein-to-creatinine percentage was 1.53?g/g of creatinine. Renal ultrasound exposed a remaining kidney sized at 10.7?cm, ideal kidney sized at 15.3?cm, and diffusely echogenic renal cortices. Midostaurin and venetoclax were halted within the 1st week of hospitalization. He was continued on IV fluids and started on Acyclovir, Posaconzole, Cefepime, Linezolid and Azithromycin. However, Roy-Bz his renal function continued to decrease and he had prolonged hemoptysis. Immunologic workup was unrevealing: antinuclear antibody titer less than 1:40, undetectable levels of anti-double-stranded DNA antibody (dsDNA), anti-glomerular basement membrane (anti-GBM), anti-myeloperoxidase antibody (anti-MPO), anti-proteinase-3 antibody (anti-PR3), and normal C3 and C4 match levels, bad hepatitis B and C serologies, and a negative HIV display. Workup for IgA Nephropathy or thrombotic microangiopathy (TMA) was unrevealing with elevated haptoglobin, no schistocytes, and bad stool studies. Ischemic acute tubular necrosis (ATN) was suspected given his significant hypotension on introduction or drug-induced acute interstitial nephritis (AIN). The patient was started empirically on methylprednisolone 1?mg/kg every 12?h for his DAH, but his renal function continued to decrease during this therapy. Within the tenth hospital day time, his creatinine increased to 7.11?mg/dL and hemodialysis was initiated for symptoms of uremia and volume overload. Since the etiology of his renal dysfunction was not obvious, a renal biopsy was wanted. The renal biopsy showed acute pauci-immune focal necrotizing GN with fibrin crescents (seen in Fig.?1), ATN (seen in Fig.?1), 38% (14 out of 37 glomeruli) global glomerulosclerosis, and less than 5% interstitial fibrosis with tubular atrophy (IFTA). The crescents were made up primarily of fibrin with only early epithelial proliferation. Segmental necrosis with fibrin crescents was seen in 39% (9 out of the 23) of the glomeruli. Interestingly, the 38% globally sclerosed glomeruli were fully obsolescent and consistent with hypertensive nephrosclerosis not DAP6 related to the acute GN. Open in a separate windows Fig.?1 a Acute tubular epithelial injury consistent with acute tubular necrosis (ATN) and mild arterial and arteriolar sclerosis. Red blood cell casts (right). Pub?=?50?m. b Crescent made up primarily of fibrin with early epithelial proliferation indicating very acute necrotizing glomerulonephritis. Pub?=?20?m. c Jones Metallic stain: very segmentally interrupted Glomerular Basement Membrane (GBM arrow). d IgA trace mesangial deposits. e IgG bad glomerulus. Roy-Bz f Electron microscopy with normal structure and no deposits He was already started on daily pulse dose methylprednisolone 500?mg for his DAH which we continued for a total of 3?days followed by daily prednisone 60?mg, IV cyclophosphamide.