(H,I) Caco2 and HCA7 cells with cytokeratin or isotype control (using CaCo2 cells) and circulation cytometry performed

(H,I) Caco2 and HCA7 cells with cytokeratin or isotype control (using CaCo2 cells) and circulation cytometry performed. crystals, and swelling upon oral intake of sevelamer, as well as the formation of neutrophil extracellular traps in proximity to small sevelamer crystals. Indeed, drug crystals reduced metabolic activity and induced barrier dysfunction and cell death in human being intestinal epithelial cells in vitro. In addition, drug crystals induced the release of neutrophil and monocyte extracellular traps. Taken together, these data raise the probability that besides additional factors including chronic kidney disease, diabetes mellitus, and hypertension, drug crystals may further amplify a pre-existing barrier dysfunction and necroinflammation inside a crescendo of local intestinal necrosis and systemic swelling/infection, as occasionally observed in individuals on ion-exchange resin therapy. 0.05; ns shows not significant (> 0.05). Sample sizes are indicated in each related figure story. 3. Results 3.1. Sevelamer Crystal-Related Intestinal Necrosis Involves Local Formation of Neutrophil Extracellular Traps A 67-year-old man with chronic kidney disease stage G4A3 and kidney atrophy was admitted to the Division of Nephrology in the Medical University or college of Graz in 2017. His past medical history included chronic hyponatremia, hypertension, schizophrenic paranoia, syncope, renal anemia, and chronic nicotine misuse. In February 2019, he returned to the hospital due to deterioration of kidney function and hyperphosphatemia (Number 1A). Serum creatinine, urea, and phosphate levels had increased compared with the first check out in 2017 (Number 1B). Therapy with the phosphate binder sevelamer (800 mg two times per day) was started. One month later on, no improvement of phosphate levels had occurred (Number 1B); consequently, the dose of sevelamer was increased to 800 mg three times per day. Mid-April 2019, he was readmitted to the hospital with abdominal pain. The patient underwent right hemicolectomy. Macroscopic and histological examination of the medical specimen revealed colon perforation, confluent fibrinoid necrosis, and ulceration of the colonic mucosa with diffuse peritonitis and sevelamer crystals (black arrow) (Number 1C,C). Sevelamer crystals were displayed as irregularly spaced fish scales of different sizes (Number 1D,E, top panel). Smaller sevelamer crystals were birefringent under polarized light (Number 1D,E, bottom panel). The dilated sigmoid colon was resected Acenocoumarol having a transition point, an end colostomy with Hartmanns pouch was created, and vacuum-assisted closure therapy was initiated. Sevelamer medication was discontinued. After four weeks, the vacuum-assisted closure was eliminated and the patient could be discharged from the hospital. Despite this severe complication, no dialysis was required. Open in a separate window Number 1 Sevelamer crystal-induced intestinal necrosis associated with neutrophil extracellular capture formation. (A) Clinical course of a patient (67 years of age) with chronic kidney disease (CKD). The intake of sevelamer due to phosphatemia and the long term decrease in kidney function caused intestinal necrosis, perforation, and peritonitis. Surgery with Acenocoumarol vacuum-assisted closure (VAC) was needed and the patient recovered. Sevelamer therapy was discontinued. (B) Serum urea, phosphate, and creatinine levels over Acenocoumarol the medical course of the same patient. (C,C) Periodic acid-Schiff (PAS) staining of sections of the colonic resection specimen from the patient. The arrow shows sevelamer crystal deposits. Magnification 25. (D,E) Hematoxylin and eosin (H&E) staining of the same resection specimen showing necrotic lesions, infiltration of cells, fibrosis, and Acenocoumarol Ly6a massive sevelamer crystal deposits. Only small sevelamer crystals are birefringent under polarized light but not big crystal people (D,E). (F,F,G,G) Fluorescence (F,G) and light (F,G) microscopy of the same colonic resection specimen stained with 4,6-diamidin-2-phenylindol (DAPI) (nuclei/DNA, blue) and neutrophil elastase to identify neutrophil extracellular capture (NET)-like structures, reddish. (G) A close-up representative image indicating decondensed non-aggregated NETs (white arrowheads), diffuse NETs with decondensed nuclei (DNA) (white arrows), and neutrophils with intact DNA/nuclei (*). Since crystalline particles can result in neutrophil necrosis and NET launch [13], we investigated NETs in the cells samples of this case of sevelamer crystal-related intestinal necrosis. Immunofluorescence and light microscopy of Acenocoumarol the colon biopsy showed that neutrophil elastase-positive neutrophils (red color) did not localize around large sevelamer crystals.