Close Modal


Currently filtering by tag: C4d

Twitter Poll (February 20, 2019)

Antibody-Mediated Rejection, Twitter Poll, Arkana Laboratories
ANSWER: B The findings are suspicious for active antibody-mediated rejection (ABMR), based on the presence of moderate glomerulitis (g2), severe peritubular capillaritis (ptc3) and C4d staining in PTCs (C4d2). Serologic evidence of DSA is advised in order to meet the criteria for diagnosis. Reference: Haas M, et al. The Banff 2017 Kidney Meeting Report: Revised diagnostic criteria for chronic active T-cell mediated rejection, antibody-mediated rejection, and prospects for integrative endpoints for next-generation clinical trials. Am J Transplant. 2018; 1-15.

Chronic Active Antibody-Mediated Rejection

A diagnosis of chronic active antibody-mediated rejection (ABMR) requires morphologic evidence of chronic tissue injury (e.g. transplant glomerulopathy), evidence of current or recent antibody interaction with the vascular endothelium (e.g. linear C4d staining of peritubular capillaries), and serologic evidence of donor specific antibody (DSA) formation.  Importantly, the revised 2017 Banff classification of ABMR and T cell-mediated rejection (TCMR) recognizes C4d positivity as a substitute for DSA for diagnosing ABMR, although DSA testing is still strongly encouraged (see reference).  The images are from a patient with an elevated serum creatinine who had undergone living unrelated kidney transplant four years ago.  The...

Antibody-Mediated Rejection

This biopsy was performed on a 37-year-old female with a history of type 1 diabetes mellitus, status post second deceased donor renal transplant, who now presents with allograft dysfunction (Cr 3.1 mg/dl) and mild proteinuria (UPC 1.1 g/g). No donor-specific antibody (DSA) data was available at the time of the biopsy. The biopsy shows severe glomerulitis and chronic transplant glomerulopathy (Fig 1), along with mild peritubular capillaritis (Fig 2) and diffusely positive C4d staining in peritubular capillaries (Fig 3). Based on the Banff 2017 kidney meeting report, this case can now be diagnosed as chronic active antibody-mediated rejection, and the...

Pushing Glass (October 10, 2017)

The patient is a 50-year-old African-American female with a past medical history significant for ESRD secondary to lupus nephritis who presents two weeks after a renal transplant with a delay in graft function. Her creatinine at the time of presentation is 9. She reports feeling fine and does not have any rashes or joint discomfort. A renal biopsy is performed on the transplanted kidney. Which is the best diagnosis? A. Acute Tubular Injury B. Thrombotic thrombocytopenic purpura C. Acute Antibody-Mediated Rejection D. Vasculitis  The correct answer is c (acute antibody-mediated rejection). The biopsy shows a constellation of findings. This includes...

Intimal Arteritis

The image in Figure 1 shows mild intimal arteritis in an allograft biopsy from a patient who had undergone a kidney transplant. Note that the mononuclear inflammatory cells are found beneath the endothelium rather than simply adherent to the endothelial surface, which may be seen with inflammatory cell margination. Remember, too, as reflected in the 2013 revised Banff working classification, that intimal arteritis may be seen in antibody-mediated rejection in addition to T-cell-mediated rejection. In the patient’s biopsy, the additional presence of linear C4d positivity in peritubular capillaries (Figure 2) and the absence of significant interstitial inflammation and tubulitis provided...

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).     ​   ​ ​   ​   ​ ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​ ​...