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Currently filtering by tag: Pyelonephritis

Acute Pyelonephritis in Transplants

Acute pyelonephritis in the transplant setting (allograft pyelonephritis) is a known cause of allograft dysfunction and a complication that occurs in approximately 10-16% of transplanted patients. Given the overlap of clinical findings between acute pyelonephritis and rejection, acute pyelonephritis is seen more often in biopsies performed on allografts than on native kidneys. This 32 year old patient presented with increased creatinine (2.6 mg/dl) 2 years after receiving a deceased donor kidney transplant. As shown in Fig 1 and 2, the biopsy shows severe neutrophilic inflammation associated with remarkable rimming of the tubules, neutrophilic tubulitis and neutrophilic casts. These features are...

Acute Pyelonephritis

This renal biopsy from a 65-year-old male with a history of E. Coli urinary tract infection and bacteremia shows severe neutrophil-rich interstitial inflammation with neutrophilic rimming of the tubules, neutrophilic tubulitis and neutrophilic casts (Figures 1-3).  These features are diagnostic of acute pyelonephritis. In addition to the aforementioned morphologic findings, a characteristic feature of acute pyelonephritis is the patchy nature of the infiltrate (Fig 4). Relatively spared areas of renal parenchyma are often intermixed with areas displaying severe tubulointerstitial inflammation.  While an ascending urinary tract infection is the main mechanism for the development of acute pyelonephritis, hematogenous infections may also...

Acute Pyelonephritis

The renal biopsy image shows features characteristic of acute pyelonephritis. There is a neutrophil-rich interstitial inflammatory infiltrate and evidence of acute tubular injury. Some tubular lumens are filled with neutrophils (arrow), and in some areas, neutrophils encircle the outer aspect of the tubules between the tubular basement membrane and the interstitium (arrowhead). In some cases, micro abscesses may even form (not shown). In most cases of ascending infection, large vessels and glomeruli are uninvolved. If arteritis or neutrophilic infiltrates involve glomeruli, the possibility of a hematogenous infectious source should be considered.