Association between urine microscopy and severe acute kidney injury in critically ill patients following non-cardiac surgery: a prospective cohort study.

BACKGROUND: Acute kidney injury (AKI) is a common and adverse complication following non-cardiac surgery. Evidence have shown urine microscopy could help early detection, differentiating the causes and predicting the progression of AKI. However, little evidence is available on AKI after non-cardiac surgery. Thus, we investigated the association between urine microscopy and severe AKI in critically ill patients after non-cardiac surgery. METHODS: This was a single-center prospective cohort study. The primary outcome was severe AKI, defined as stage 2 or 3 according to maximal KDIGO criteria within 7 days following non-cardiac surgery. Urine microscopy immediately, 6 and 12 hours after surgical intensive care unit (SICU) admission were examined and graded by a urine microscopy score (UMS) based on the observed quantification of renal tubular cells and casts in the sediment. Then, multivariate Logistic regression models were used to analyze the associations between UMS and postoperative severe AKI. RESULTS: From May 20, 2019 to November 24, 2020, 661 patients were enrolled with 147 patients (22.2%) developing postoperative severe AKI. Multivariate Logistic regression model showed elevated UMS (≥1) 6 and 12 hours after SICU admission were independently associated with postoperative severe AKI (OR 2.200, 95% CI: 1.182-4.095, P=0.013 and OR 2.949, 95% CI: 1.657-5.248, P<0.001, respectively). Furthermore, higher UMS 6 hours after SICU admission demonstrated correlation with greater risk of severe AKI with OR 3.887 (95% CI: 1.430-10.563) for UMS ≥3 and OR 2.429 (95% CI: 1.237-4.770) for UMS =1-2. The specificity and sensitivity of UMS ≥1 for severe AKI was 93.8% (95% CI: 91.7-95.9%) and 15.6% (95% CI: 9.7-21.5%), respectively. While the negative and positive predictive value was 79.5% (95% CI: 76.3-82.7%) and 41.8% (95% CI: 28.8-54.8%), respectively. In addition, patients with higher UMS (≥3, 1-2 and 0) had significantly more postoperative complications and longer SICU stay; and they also showed a trend toward other adverse postoperative outcomes. CONCLUSIONS: Early urine microscopy was independently associated with severe AKI in critically ill patients following non-cardiac surgery with higher UMS related to greater risk. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT03880110.

[A new method for the detection of platelet derived microparticles by cytometric bead array and its evaluation].

OBJECTIVE: To establish a new method for the detection of platelet derived microparticles (PMPs) by cytometric bead array and to evaluate the characteristic of this method. METHODS: Using detection beads coated with monoclonal antibody against platelet glycoprotein IIIa to capture PMPs, then using CD41 PE to react with PMPs captured by detection beads, finally using flow cytometer detect beads-PMPs-CD41 PE complex. Anticoagulant, reaction time and other condition were optimized. Then reproducibility and linear range of this method were evaluated. PMPs of 45 health adults were determined by this method. RESULTS: Detection beads were stable in 4 degrees C for over 90 days (coefficient of variance was 0.65%) which matched the basic request of clinical detection. CTAD could restrain the in vitro release of PMPs efficiently; The reaction could reach maximum combination at room temperature after 4 hour; Non-specific absorbance of detection beads could be eliminated by washing of PBS. This method had preferable reproducibility (CV in batch was 6.8%; CV between batch was 10.4%) and a wide linear range from 0 to 200 microl of platelet activation suspension (r = 0.9962). PMP level of 45 health adults was 1.031-1.766. CONCLUSION: PMPs can be detected exactly by cytometric bead array, and it's important for PMPs detection to be an assistant for diagnosis of haemorrhagic and thrombotic diseases.

Impact of surgery and epirubicin intravesical chemotherapy on peripheral blood dendritic cell subsets in patients with superficial urothelial carcinoma of the bladder.

BACKGROUND: Superficial urothelial carcinoma (SUC) of the bladder is a common urinary tract tumor in China. There is a high recurrence rate of this tumor even after surgery and intravesical instillation. Previous reports have described a suppression of the immune system in cancer patients. Dendritic cells (DCs) play a pivotal role in the induction of an effective antitumor immune response. The aim of this study was to investigate the effects of surgery and epirubicin intravesical chemotherapy (IC) on peripheral blood DCs in subsets of patients with bladder SUC. METHODS: A total of 66 SUC patients and 38 healthy controls were enrolled in this study. All the patients had undergone transurethral resection (TUR) of their cancer and adjunctive IC after tumor removal. The patients were divided into a non-recurrence group (n = 40) and a recurrence group (n = 26) based on the presence or absence of tumor recurrence. Blood samples were taken preoperatively (PreOP), on postoperative days (POD) 1 and 7, and at postoperative month (POM) 3. Flow cytometric analysis was used for the determination and quantitation of the surface markers CD80 and CD86 in circulating DC subsets. RESULTS: The preoperative percentages of myeloid dendritic cells (mDCs) and expression of CD80 and CD86 were impaired in SUC patients compared to healthy controls (P < 0.05). The percentages of mDCs and these surface markers decreased significantly on POD 1 and increased on POD 7, remaining higher than the preoperative values in POM 3 (P < 0.05). The percentages of mDCs, and CD80 and CD86 in the non-recurrence group on PreOP, POD 7, and POM 3 were higher than those in recurrence group. CONCLUSIONS: Surgical removal of SUC and adjunctive IC were associated with improved circulating mDC counts and function. Persistent depression of mDC counts and function after treatment in recurrence patients indicated lower antitumor immunity that may lead to tumor recurrence.

Establishment of a flow cytometric assay for determination of human platelet glycoprotein VI based on a mouse polyclonal antibody.

Glycoprotein VI (GPVI) is the major signaling receptor for collagen on platelets. Recent studies suggest that the surface density of GPVI is related to the activation of platelets by collagen. To measure the level of GPVI on platelets, a mouse polyclonal antibody BJ010 was prepared using an amplified fragment of extracellular domain in GPVI. The specific reactivity of BJ010 was identified by anti-GPVI specific monoclonal antibody 11a12 using immunoprecipitation, sandwich enzyme-linked immunosorbent assay (ELISA) and flow cytometry. The antibody BJ010 recognized both native and denatured human GPVI so that it was used to set up a flow cytometric assay to detect the level of GPVI in normal subjects. The relative level of GPVI on platelets was detected in 101 healthydonors. The median geometric mean fluorescence intensity (GMFI) of platelet GPVI level was 57.7. The variation between minimum and maximum values of platelet GPVI and integrin alpha2beta1 were found to be 3.5- and 4.1-fold, respectively, in the normal subjects. There was a week correlation between the amount of GPVI and integrin alpha2beta1 on platelet surfaces. For the method, the intraassay and interassay coefficient of variation was 6.3% and 8.8%, respectively. The flow cytometric assay described here provides a simple, reliable, reproducible, and readily available means of quantitation of collagen receptor GPVI density on the platelet surface in a larger number of blood samples.