There Is High Sensitive and Specific Correlation Between Frozen and Permanent Sections in Renal Transplant Biopsies.

INTRODUCTION: Frozen sections have been used for evaluating tumors and margins during daily practice in pathology with high specificity and sensitivity (>90% for both indices both at national level and in our department). The correlation between frozen section tissue for immunofluorescent (IF) studies and permanent sections for light microscopy, along with electron microscopy, is critical for constructing a final renal pathology diagnosis. METHODS: We studied the correlation between the frozen sections for IF studies and separate fragments of tissue for permanent light microscopic sections in our renal transplant biopsies for purposes of quality control. Frozen sections for IF sections were compared with permanent sections for light microscopy in 122 renal transplant biopsies, using inflammation as the key criterion (63 with no inflammation and 59 with inflammation) to determine the correlation. RESULTS: There was high sensitivity (94.9%) and specificity (92.1%) for the correlation between the frozen section and permanent sections. CONCLUSIONS: Our data suggest that parts of renal transplant biopsy tissue dissected to freeze for IF studies and for light microscopy were highly correlated to ensure a high quality of renal tissue dissection for the final diagnosis in renal transplant biopsies.

Feasibility of BK Virus Real-Time PCR Testing in Renal Graft Biopsies With Negative SV40 Staining.

BACKGROUND: BK virus (BKV)-associated nephropathy (BKVAN) is often associated with renal graft dysfunction. When renal transplant recipients present with high clinical suspicion for BKVAN (high serum and urine BKV titer with graft dysfunction) but their graft biopsies stain negatively for BKV, non-correlated situations between the two tests often lead to a dilemma about how to treat them. METHODS: This retrospective investigation was conducted to determine how real-time quantitative PCR (qPCR) for BKV, routinely applied to serum and urine, could be helpful in identifying the existing BKV in biopsy tissue stained negatively for BKV. RESULTS: DNA was extracted from each specimen through the use of five 10-µm curls from the tissue block with use of the QIAamp DNA FFPE Tissue Kit (Qiagen), followed by BKV qPCR to determine copies of BKV/µg of biopsy tissue DNA. Group 1 (11 negative renal controls for BKV) demonstrated 0 to 9 BKV copies/µg DNA. Except for 3 focally staining cases showing low BKV, the remaining 10 positive renal controls in group 2 (13 positive transplant biopsies staining positively) demonstrated elevated BKV up to 160 million copies/µg DNA. Group 3 transplants (13 uncertain transplants with negative BKV staining but positive liquid BKV) were negative for BKV (0-12 copies/µg) in 4 of 13, had low BKV copies (36-346 copies/µg) in 5 of 13, and had high BKV copies (17,240-526,945 copies/µg) in 4 of 13 cases, through the use of qPCR. CONCLUSIONS: The data indicate that qPCR from paraffin-embedded tissue as a backup test is sensitive for ruling in/out BKV infection in renal transplant biopsies, particularly in uncertain cases.

Renal allograft outcome in recipients of positive-crossmatch combined liver-kidney transplantation.

BACKGROUND: Successful kidney transplantation despite positive crossmatch (+CXM) before transplantation is well recognized in combined liver-kidney transplant (CLKT) recipients. This is probably due to immunologic protection of the renal allograft (RA) conferred by the liver allograft. However, occurrences of antibody-mediated rejection and poor long-term RA outcome is also documented with +CXM CLKT recipients, suggesting that such immunologic protection may not be universal. METHODS: A total of 1,401 CLKT recipients with known status of pre-transplantation CXM were identified from the United Network for Organ Sharing registry from January 1, 1986, to December 31, 2006. Univariate analysis for significant differences in clinical variables and Kaplan-Meier estimate for patient and graft survivals were performed. The results were compared between positive and negative CXM groups. RESULTS: Pre-transplantation +CXM was seen in 17.3% (242/1401) of CLKT recipients studied. The demographic and clinical characteristics were similar between the groups, except for higher panel reactive antibody level and CXM positivity in female recipients. Outcome analysis showed higher RA rejection (19.3% vs 10.8%; P = .026) and increased hospital length of stay (37.3 ± 46.0 vs 28.8 ± 33.2 days; P = .028) in the +CXM group. RA survivals at 1, 3, and 5 years were 8%, 7%, and 6% lower in the +CXM group. The patient and liver allograft survivals were not different between the groups. CONCLUSIONS: In CLKT recipients with pre-transplantation +CXM, the immunologic protection of RA conferred by the liver allograft is less robust than previously perceived and may lead to higher rejection rate and poor RA outcome. This can be mitigated with routine pre-transplantation CXM.

Case of fulminant leptospirosis in a renal transplant patient.

We present a case of fulminant leptospirosis that was acquired in the suburban area by a 48-year-old male renal transplant recipient. He developed acute renal and hepatic failure with profound jaundice. Spirochetes were identified on liver biopsy. Weil's disease was suspected, and the diagnosis was further supported by a positive serum Leptospira interrogans icterohaemorrhagiae antibody titer. Unfortunately, he suffered from recurrent lower gastrointestinal bleeding, had a prolonged hospital course, and eventually succumbed to overwhelming sepsis. This case is the third report to our knowledge of leptospirosis in a renal transplant recipient in the English literature.

Contrast-induced acute kidney injury in renal transplant recipients after cardiac catheterization.

Renal transplant (RTX) recipients remain at high-risk for acute kidney injury (AKI) despite having improved renal function and quality of life after transplantation. We sought to identify the incidence and risk factors for contrast-induced AKI in RTX recipients after cardiac catheterization at our institute as identified by electronic records. After excluding patients on dialysis at time of procedure due to failed transplant and who did not have post-exposure creatinine values within 3 days, we reviewed 77 procedures on 57 patients. We studied one case per patient (the most recent procedure). Among the 57 patients, 42 were male, 42 were Caucasian and mean age was 58.2 +/- 10.1 years. Mean serum creatinine 24 h pre-procedure was 1.7 +/- 0.8 mg/dl. Contrast-induced AKI, defined as rise in serum creatinine of 25% or 0.5 mg/dl within 3 days post-catheterization, occurred in 9 procedures (15.8%). One procedure was complicated by AKI requiring dialysis. AKI occurred more frequently with use of low-osmolar contrast (ioxaglate or iohexol) in comparison with iso-osmolar contrast (iodixanol) (9/36 vs. 0/21, p = 0.019). Patients who received prophylactic N-acetylcysteine had lower incidence of AKI than those who did not (4/41 vs. 5/16, p = 0.046). Exact logistic regression analysis revealed odds ratio of developing AKI with use of low-osmolar vs. iso-osmolar contrast to be 7.747 (1.101 - yen); p = 0.0381). Contrast-induced AKI was common in RTX recipients after cardiac catheterization. Iso-osmolar contrast was associated with a lower risk of contrast-induced AKI in comparison with low-osmolar contrast.

Measuring the adequacy of hemodialysis access.

Vascular access morbidity is still an important problem. The risk of thrombosis increases in prosthetic grafts as the access flow decreases below 600 ml/min, whereas native arteriovenous accesses can maintain patency at much lower flows, in some cases flows below those needed to deliver adequate dialysis. Intra-access pressures are also dissipated differently in the two access types. These differences between native and prosthetic grafts determine the utility of the monitoring techniques that are useful for detecting stenosis and assessing function in the two access types. Modern non-urea methods for measuring access recirculation are therefore useful in native but not in graft hemoaccesses. Direct or indirect intra-access pressure measurements and direct flow measurements are most useful in grafts to detect and then correct lesion before thrombosis.