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Arkanines: Truman

Meet Truman! He belongs to our director, Dr. Walker (and our real boss, Mrs. Gail). Truman enjoys going to daycare, playing in a mud pit, eating chicken jerky, and having goat's milk on top of his dog food.

Myoglobin Casts

A 54-year-old man with a history of hypertension and hypercholesterolemia presented with complaints of generalized “muscle stiffness” and cola-colored urine. He was found to have markedly elevated serum creatinine and creatine kinase levels. A renal biopsy showed acute tubular injury with numerous pigmented casts (Fig 1), which were proven to be myoglobin casts by immunohistochemistry (Fig 2). The etiology of the patient’s myoglobinuria was thought to be statin medication, the dose of which had recently been increased. Here is a link to a recent article describing the morphologic spectrum of myoglobin casts in renal biopsies:

Pushing Glass (April 18, 2017)

A 45 year-old man received renal transplantation for HCV-associated end stage renal disease. He is currently treated with Sofobuvir, Tacrolimus and ACEI. He developed renal function impairment (Serum Cr increased to 2.3 mg/dL) with mild proteinuria. Based on the renal biopsy images, which is the most likely diagnosis? A. Severe acute tubular injury due to Sofobuvir B. Calcineurin inhibitor toxicity C. Polyomavirus nephropathy D. Tubular injury secondary to cryoglobulinemia E. Diabetic nephropathy     The answer is B. The light microscopic examination demonstrates isometric vacuolization of tubular epithelial cells, severe hyaline arteriolopathy and a striped pattern of fibrosis. These features...

Diagnose This! (April 17, 2017)

What is this stain and what does this finding mean in a transplant patient (Hint: It’s not a vascular marker).     ​   ​ ​   ​   ​ ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​ ​...

Necrotizing Vasculitis

Necrotizing vasculitis as shown using fluorescence with DAPI-FITC-Texas Red excitation on an H&E stained section. Subtle and not so subtle necrotizing areas are seen easily using this fluorescence technique. The section shows necrotizing vasculitis in an 87-year-old male who presented with hematuria, proteinuria and a creatinine of 2.5 mg/dl. Following the biopsy, ANCA serologies were ordered with cANCA positivity.


Photomicrographs show extensive interstitial and glomerular deposition of Congo red positive material that stains positive for LECT2. Despite being one of the most recently described amyloid proteins, amyloid composed of leukocyte chemotactic factor 2 (ALECT2) is actually quite prevalent. Two large case series focusing on renal amyloidosis have identified ALECT2 as one of the most common forms of amyloidosis involving the kidney along with AL and AA amyloid.1-4 Additionally, a large case series in the liver identified it as the second most common form of hepatic amyloidosis.5 The vast majority of patients suffering from this disease in the United States...


We can't thank the people at FedEx enough! Our local FedEx staff is just as committed to our patients as we are. We couldn't do this without them!

Jones Stain

The silver impregnation stain is a key method of identifying basement membranes in human tissue, and its application in renal pathology is nearly universal. Notice in this image (Fig 1) how clearly demonstrating the capillary basement membrane using the silver stain allows one to distinguish cells within the capillary lumens from those “extracapillary” cells which are forming the glomerular crescent. In 1951, David B. Jones, MD, reported the development of a periodic acid silver reaction adapted specifically for the kidney which better highlighted basement membranes (American Journal of Pathology, Dec 1951: 991-1009). Most renal pathologists still rely heavily on the Jones...

Arkana Physician Spotlight: Md Shahrier Amin, MD, PhD

Dr. Amin joined Arkana Laboratories in 2016 after successful completion of fellowships in cardiovascular pathology (2015) and renal pathology (2016) at The Mayo Clinic, Rochester. Dr. Amin is involved with our social media team and produces many of our "Pushing Glass" case presentations. In his free time, Dr. Amin enjoys playing the guitar and spending time with family.  Interesting Fact: When Dr. Amin was a kid, he wanted to be an astronomer or a biologist. We’re glad he ultimately decided to pursue renal pathology and glad to have him as a part of the Arkana Laboratories family!

Cryoglobulinemic Glomerulonephritis

Figure 1: PAS-stained section showing a glomerulus with a membranoproliferative pattern of glomerular injury characterized by mesangial matrix expansion and hypercellularity, associated with endocapillary proliferation, glomerular basement membrane double contour formation and accentuation of the lobular architecture. Furthermore, the capillary loops show frequent, large, PAS-positive pseudothrombi, highly suspicious for cryoglobulinemic glomerulonephritis. Cryoglobulins are circulating immunoglobulins that precipitate at 4°C and redissolve at 37°C. They are classified into three types according to the immunochemical composition of the immunoglobulins. Type I cryoglobulins are composed of a single monoclonal immunoglobulin, usually IgM, and are commonly associated with lymphoproliferative disorders such as Waldenstrom macroglobulinemia,...