Bleeding self-assessments by patients with immune thrombocytopenia (ITP): An agreement study.

We designed anagreement study to compare the results of bleeding assessments done in tandem by ITP patients and trained research staff. We used a modified version of the ITP Bleeding Scale, which captured the patients' worst bleeding event at any of nine anatomical sites since the time of the last assessment. Interrater agreement was determined using the 2-way kappa for the assessment of severe vs. non-severe bleeds. We analyzed 108 consecutive patients with ITP from the McMaster ITP Registry who had duplicate bleeding assessments. Two-way agreement was excellent for gynecological (k = 0.86, 95% CI 0.71-1.02), gastrointestinal (k = 1), genitourinary (k = 1), pulmonary (k = 1) and intracranial (k = 1) bleeds; good for skin (k = 0.68, 95% CI, 0.54-0.82), oral (k = 0.76, 95% CI, 0.53-0.98) and ocular (k = 0.66, 95% CI, 0.04-1-28) bleeds; and moderate for epistaxis (k = 0.58, 95% CI, 0.21-0.95). Bleeding self-assessments by ITP patients were similar to trained research staff, but disagreements in severity grades were more frequent with skin bleeds, oral bleeds and epistaxis. Bleeding self-assessments could simplify bleeding assessments in clinical trials.

Antibodies against platelet factor 4 and the risk of cerebral venous sinus thrombosis in patients with vaccine-induced immune thrombotic thrombocytopenia.

BACKGROUND: Vaccine-induced immune thrombotic thrombocytopenia (VITT) is a rare complication of adenoviral vector-based vaccines against SARS-CoV-2. This syndrome is caused by antibodies against platelet factor 4 (PF4; CXCL4) that lead to platelet activation and is characterized by thrombocytopenia and thrombosis in unusual locations, including cerebral venous sinus thrombosis (CVST). VITT can be classified based on anti-PF4 antibodies properties in vitro: those that require PF4 to activate platelets (PF4-dependent) and those that can activate platelets without additional PF4 (PF4-independent) in the serotonin release assay. OBJECTIVES: We aim to characterize the relationship of VITT platelet-activating profiles with CVST. METHODS: We conducted a retrospective cohort study involving patients with confirmed VITT who were tested between March and June 2021. Data were collected with an anonymized form and cases were identified as VITT with high clinical suspicion according to platelet activation assays. Anti-PF4 antibody binding regions on PF4 were further characterized with alanine scanning mutagenesis. RESULTS: Of the patients with confirmed VITT (n = 39), 17 (43.6%) had PF4-dependent antibodies and 22 (56.4%) had PF4-independent antibodies. CVST occurred almost exclusively in PF4-independent patients (11 of 22 vs 1 of 17; P < .05). Additionally, PF4-independent antibodies bound to 2 distinct epitopes on PF4, the heparin-binding region and a site typical for heparin-induced thrombocytopenia antibodies, whereas PF4-dependent antibodies bound to only the heparin-binding region. CONCLUSION: These findings suggest that VITT antibodies that cause PF4-independent platelet activation represent a unique subset of patients more likely to be associated with CVST, possibly due to the 2 different types of anti-PF4 antibodies.

Accuracy of International Classification of Diseases, 10th Revision Codes for Identifying Sepsis: A Systematic Review and Meta-Analysis.

Administrative databases are increasingly used in research studies to capture clinical outcomes such as sepsis. This systematic review and meta-analysis examines the accuracy of International Classification of Diseases, 10th revision (ICD-10), codes for identifying sepsis in adult and pediatric patients. DATA SOURCES: We searched MEDLINE, EMBASE, Web of Science, CENTRAL, Epistemonikos, and McMaster Superfilters from inception to September 7, 2021. STUDY SELECTION: We included studies that validated the accuracy of sepsis ICD-10 codes against any reference standard. DATA EXTRACTION: Three authors, working in duplicate, independently extracted data. We conducted meta-analysis using a random effects model to pool sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV). We evaluated individual study risk of bias using the Quality Assessment of Diagnostic Accuracy Studies tool and assessed certainty in pooled diagnostic effect measures using the Grading of Recommendations Assessment, Development, and Evaluation framework. DATA SYNTHESIS: Thirteen eligible studies were included in the qualitative synthesis and the meta-analysis. Eleven studies used manual chart review as the reference standard, and four studies used registry databases. Only one study evaluated pediatric patients exclusively. Compared with the reference standard of detailed chart review and/or registry databases, the pooled sensitivity for sepsis ICD-10 codes was 35% (95% CI, 22-48, low certainty), whereas the pooled specificity was 98% (95% CI: 98-99, low certainty). The PPV for ICD-10 codes ranged from 9.8% to 100% (median, 72.0%; interquartile range [IQR], 50.0-84.7%). NPV ranged from 54.7% to 99.1% (median, 95.9%; interquartile range, 85.5-98.3%). CONCLUSIONS: Sepsis is undercoded in administrative databases. Future research is needed to explore if greater consistency in ICD-10 code definitions and enhanced quality measures for ICD-10 coders can improve the coding accuracy of sepsis in large databases.