arrow-right-realarrow-right-whitearrow-rightback-to-topdoctordownloadfacebookinstagramlogo-markerlogo-wordmarkpodcastsearchsearch_whitetwitter
Close Modal

Blog


Currently filtering by tag: Acute tubular injury

Hemosiderosis

An 80-year-old white male presents with a creatinine of 4.2 (baseline 1.1) on routine lab examination. His medical history is significant for coronary artery disease, aortic valve replacement, hypertension, and peripheral artery disease. He reports no episodes of dehydration and reports that he has been in his normal state of health. Figure 1 shows a normal glomerulus. Figure 2 shows a mild interstitial fibrosis. Figure 3 shows brown spherules within the tubular epithelial cells. Figure 4 confirms the presence of iron within these brown spherules. This is a case of renal hemosiderosis. The presence of iron deposits speaks towards intravascular...

Diagnose This (February 25, 2019)

What is your diagnosis?     ​ ​   ​   ​ ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​ ​   ​ ​   ​ ​   ​ ​     ​   ​   ​ ​  ...

Renal Oxalosis

A 25-year-old female presents to the hospital with malaise and a creatinine of 3.5. She reports that she was in her normal state of health until about 2 weeks ago when she had the “flu.” The patient has minimal proteinuria and bland urine sediment. A kidney biopsy was obtained. Figure 1 shows a normal glomerulus. Figure 2 shows severe chronicity. Figure 3 and 4 show polyhedral clear crystals within the tubular lumina. Figure 5 shows an increased number of oxalate crystals under polarized light. Renal oxalosis is characterized by excess deposition of calcium oxalate crystals within the kidney. There are...

Step By Step

The biopsy is from a 65 year-old female who presented with acute renal failure and elevated creatinine up to 1.9 mg/dl.  She has non-ischemic cardiomyopathy and protein electrophoresis is positive for lambda light chains.  Serologies for ANA and rheumatoid factor are within normal limits.  A biopsy was performed to rule out paraprotein associated disease and there was a specific concern for amyloidosis, due to cardiac changes. The biopsy consisted of a good sample, contained multiple cores of tissue and more than 20 glomeruli.   The glomeruli were very unremarkable by light microscopy – loops were open, with regular contours, and no...

Diagnose This (November 19, 2018)

What is your diagnosis? What additional stains would you like to confirm your diagnosis?     ​ ​   ​   ​ ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​ ​   ​ ​   ​ ​   ​...

Twitter Poll (September 26, 2018)

ANSWER: D Hall’s stain is used to confirm the presence of bile casts. This technique uses the oxidizing action of Fouchet’s reagent to convert the bile pigment (bilirubin) into an easily identifiable green color (biliverdin). Bile pigments appear green against a yellow background. The color ranges from olive green to emerald green, depending upon the concentration of bilirubin. REFERENCES: Hall MJ. A staining reaction for bilirubin in sections of tissue. Amer J Clin Path, 1960; 34:313-316. Luna LG. Manual of Histologic Staining Methods of the Armed Forces Institute of Pathology, 3rd ed., McGraw-Hill, N.Y., c. 1968, p.174. van Slambrouck CM,...

Diagnose This (July 16, 2018)

What is your diagnosis in this native kidney biopsy? And for bonus points, what do you suspect is the underlying etiology of the diagnosis?   ​   ​ ​   ​   ​ ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​...

Hemoglobin Casts

This 58-year-old African American male without significant past medical history presents with fatigue and weakness. During workup, he was found to have anemia, mild thrombocytopenia, elevated LDH, low haptoglobin and acute kidney injury. The serum creatinine at presentation was 5.5 mg/dl. A renal biopsy was performed and shows acute tubular injury with numerous granular and globular eosinophilic (Fig 1) and fuchsinophilic casts (Fig 2) within the tubular lumens. A myoglobin immunoperoxidase stain is negative (not shown) and a hemoglobin stain is diffusely positive within the pigmented casts. Otherwise, the glomeruli and vessels appear normal, without evidence of microangiopathy. These findings...

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...