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Currently filtering by tag: interstitial fibrosis

Twitter Poll (February 19, 2020)

Twitter Poll, Oxford IgAN Classification
ANSWER: C The Oxford IgAN Classification takes in consideration the percentage of interstitial fibrosis and tubular atrophy (T) as one of the histologic findings to predict outcome, irrespective of treatment. T0 represents <25%, T1 26-50% and T2 >50% cortical involvement. REFERENCES: 1. Trimarchi et al. Oxford Classification of IgA nephropathy 2016: an update from the IgA Nephropathy Classification Working Group. Kidney Int 2017; 91(5):1014-1021. 2. Haas et al. A multicenter study of the predictive value of crescents in IgA nephropathy. J Am Soc Nephrol 2017; 28:691-701.

Methotrexate-Induced Crystal Nephropathy

Methotrexate-induced acute kidney injury, Methotrexate-Induced Crystal Nephropathy, teaching points, Arkana Laboratories
The patient is a 50-year-old male who presents with a creatinine of 4.2 mg/dL (baseline 1.0 mg/dL). He has been receiving high dose methotrexate for treatment of osteosarcoma. Image 1 shows a normal glomerulus. Image 2 shows moderate interstitial fibrosis. Image 3, 4, and 5 shows polarizable silver-positive crystals within the tubular lumens. This is a case of methotrexate-induced crystal nephropathy. Methotrexate-induced crystal nephropathy is characterized by acute tubular injury with scattered intratubular and interstitial needle-shaped, golden-brown crystals which are frequently arranged in annular structures. The crystals show birefringence under polarized light and are methenamine silver positive.  Methotrexate-induced crystal nephropathy...