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Currently filtering by tag: Calcium oxalate

Twitter Poll (July 8, 2020)

Twitter Poll, Deficiency of adenine phosphoribosyltransferase , APRT, Arkana Laboratories
ANSWER: D Renal oxalosis is a progressive tubulointerstitial disease which can be primary or secondary in nature. Specifically, secondary causes can be due to increased ingestion or absorption of sources of oxalate, decreased excretion, and certain vitamin imbalances. Oxalosis secondary to ingestion can occur with ingestion of oxalate containing foods such as rhubarb, spinach, peanuts, tea, starfruit, and ethylene glycol poisoning, among others. Increased absorption of oxalate containing substances occurs in maladaptive states such as after gastric/intestinal bypass surgery, prolonged antibiotic use, Crohn's disease, pancreatic insufficiency, and in short bowel syndrome. Other causes of oxalosis would include hypervitaminosis C, vitamin...

Diagnose This (July 1, 2019)

Renal Oxalosis, arkana laboratories, renal pathology, kidney biopsy, Diagnose This
What is your diagnosis?       ​ ​   ​   ​ ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​ ​   ​ ​   ​ ​   ​ ​     ​   ​   ​ ​...

Bile Stained Calcium Oxalate Crystals

A renal biopsy was performed on this 75-year-old female who presented with acute liver failure, jaundice and acute renal failure (serum creatinine 6.4 mg/dl). The predominant biopsy findings are those of acute tubular injury with scattered translucent crystals which show a fan-like morphology (Fig 1) and birefringence upon polarization (Fig 2), consistent with calcium oxalate crystals. Due to the paucity of these crystals, they are favored to represent non-specific deposition in the setting of ongoing tubular injury. Interestingly, the deposited calcium oxalate crystals are bile-stained (Fig 1), a phenomenon which may be seen in the setting of hyperbilirubinemia. Although not...

Oxalate Due to Vitamin C

A 51-year-old female with a history of SLE was found to have acute renal failure. There was no evidence of glomerular proliferation by light microscopy but the biopsy did show (A) focal tubules with intraluminal and intracytoplasmic refractile crystals (arrows) (hematoxylin and eosin; original magnification × 100).  (B)  There are numerous intra-tubular birefringent crystals visible under polarized light (hematoxylin and eosin; original magnification × 50). These findings are consistent with kidney injury due to oxalate nephropathy. Known causes of oxalate nephropathy include primary hyperoxaluria, ethylene glycol intoxication, enteric hyperoxaluria (e.g. due to gastric bypass, chronic pancreatitis, small bowel resection, or...

Randall’s Plaques

Randall’s plaques are microscopic calcium phosphate deposits in the basement membranes of the thin loops of Henle. These plaques act as anchored nucleation sites for the formation of calcium oxalate crystals and are thought to play an important role in a subset of patients with calcium oxalate stones. They are rarely seen on medical kidney biopsies due to their location in an infrequently biopsied site. When present, basophilic crystalline deposits are present along tubular basement and nearby vascular bundles in the deep medulla as seen in these H&E-stained sections. These deposits highlight by von Kossa stain, a special stain which...

Oxalate Nephropathy

This biopsy is from a patient with metabolic acidosis, a CPK of 8000 mg/dl a creatinine of 22 mg/dl on admission. The H&E stained section shows birefrigent bluish crystals consistent with calcium oxalate crystals on a background of acute tubular injury. The extensive number of intratubular crystals associated with acute tubular injury support renal oxalosis as the cause of the renal failure. (H&E with polarized light, 200x)

Oxalate Nephropathy

H&E stained section (Fig. 1) demonstrating acute tubular injury with frequent translucent intratubular crystalline deposits on a background of severe tubulointerstitial scarring. The crystals show birefringence under polarized light (Fig. 2) characteristic of renal oxalosis. After the biopsy, this 60-year-old male admitted consumption of small quantities of ethylene glycol over the past 16 months.  Other causes of secondary renal oxalosis include enteric forms (Crohn’s disease, celiac sprue, pancreatic insufficiency, small intestinal or gastric bypass or resection), over-ingestion of oxalate containing foods (e.g., dark leafy vegetables, rhubarb, kale, starfruit, tea, spinach, sesame seeds, almonds, peanuts, beets, buckwheat flour, chocolate soy milk),...