Research and Practice in Thrombosis and Haemostasis最新文献

Background: Wells score comprises subjective elements, making physicians reluctant to use Wells score or cause them to use it incorrectly.

Objectives: To develop and internally validate a prediction score that is objective and simple for evaluating suspected deep vein thrombosis (DVT), with a safety comparable with that of Wells score.

Methods: We performed a post hoc analysis using data from the Ri-Schedule study (NCT02486445) involving suspected DVT patients at Østfold Hospital's Emergency Department, Norway (2015-2018). Candidate variables were identified through bootstrapping technique, with a confirmed DVT diagnosis as the outcome variable. Sensitivity, specificity, negative predictive value (NPV), and positive predictive values (PPV) were estimated and compared with the 2-tier Wells score.

Results: Among 1312 patients (median age, 64 years [IQR, 52-73]; 55% women), 19.9% were diagnosed with DVT. Exploration of 30 variables identified tenderness along deep veins and previous venous thromboembolism as significant predictors (selection frequency >60% in 1000 bootstrapping samples). The derived score categorized 450 patients with 0 items as unlikely to have DVT, of whom 8.0% were diagnosed with DVT, compared with 8.2% in DVT unlikely category according to Wells score. Compared with Wells score, the derived score demonstrated sensitivity of 86.2 (95% CI, 81.4-90.2) vs 80.1 (95% CI, 74.7-84.8), specificity of 39.4 (95% CI, 36.4-42.4) vs 55.3 (95% CI, 52.2-58.3), NPV of 92.0 (95% CI, 89.4-94.0) vs 91.8 (95% CI, 89.7-93.5), and PPV of 26.1 (95% CI, 24.8-27.5) vs 30.8 (95% CI, 28.9-32.8). When incorporating D-dimer cutoff of <0.5 µg/mL, the derived score had sensitivity of 99.6 (95% CI, 97.9-99.9), specificity of 16.1 (95% CI, 13.1-18.4), NPV of 99.4 (95% CI, 96.0-99.9), and PPV of 22.8 (95% CI, 22.3-23.3).

Conclusion: The derived DVT score, with 2 objective variables, had a comparable safety with that of the Wells score. However, an external validation is mandated prior to clinical use.

Background: Postpartum hemorrhage is considered a risk factor for pregnancy-associated complement-mediated hemolytic uremic syndrome (CM-HUS; previously known as atypical hemolytic uremic syndrome) but has not been systematically studied.

Objectives: To systematically examine the role of postpartum hemorrhage in precipitating CM-HUS and to describe the characteristics of postpartum hemorrhage-associated CM-HUS, its prognosis and recommended management.

Methods: A systematic review of individual participant data from case series and reports in addition to a case series from our institution. Search terms were "thrombotic microangiopathy," "atypical hemolytic uremic syndrome," and "complement mediated" combined with "pregnancy," "postpartum," and/or "postpartum hemorrhage". Cases of thrombotic microangiopathy other than CM-HUS were excluded. Outcomes were clinical and laboratory characteristics of postpartum hemorrhage-associated CM-HUS, treatment, and outcomes.

Results: Thirty-three studies comprising 48 women with postpartum hemorrhage-associated CM-HUS and 3 patients from our institution were included in the study. Most women presented at term (28/45; 62%), delivered by cesarean section (21/41; 51%), and had pregnancy complications, mainly preeclampsia (16/51; 31%) or fetal demise (9/51; 18%). Hematological and renal abnormalities usually appeared within the first 24 hours postdelivery. The median platelet count was 46 × 10⁹/L (IQR, 26-72), and the median maximal lactate dehydrogenase was 2638 U/L (IQR, 1620-3588). Renal function normalized in 20/23 (87%) women treated with C5 inhibitors with or without plasma exchange; in 7/11 (63%) women treated with plasma exchange alone, but only in 3/17 (18%) patients treated with supportive care. Patients treated with C5 inhibitors and/or plasma exchange achieved significantly better renal outcomes compared with supportive care alone (P < .001).

Conclusion: CM-HUS is a rare complication following postpartum hemorrhage and occurs mainly in women with preeclampsia and/or following cesarean section. Patients treated with C5 inhibitors and/or plasma exchange had a better renal prognosis compared with patients who received supportive treatment alone.