[Risk of thrombosis recurrence among patients with COVID-19- and surgery-associated venous thromboembolism]. / Riesgo de recurrencia de la trombosis en pacientes con tromboembolia venosa asociada a COVID-19 y a cirugía.

Introduction: Recent surgery is a well-known major transient risk factor for venous thromboembolism (VTE) due to the low risk of VTE recurrence after anticoagulation is discontinued. On the other hand, the risk of VTE recurrence among patients with COVID-19-associated VTE is unknown. This study aimed to compare the risk of VTE recurrence between patients with COVID-19- and surgery-associated VTE. Methods: A prospective observational single-center study was performed including consecutive patients diagnosed with VTE in a tertiary hospital from January 2020 to May 2022 and followed up for at least 90 days. Baseline characteristics, clinical presentation, and outcomes were assessed. The incidence of VTE recurrence, bleeding, and death was compared between both groups. Results: A total of 344 patients were included in the study: 111 patients with surgery-associated VTE and 233 patients with COVID-19-associated VTE. Patients with COVID-19-associated VTE were more frequently men (65.7% vs 48.6%, p = 0.003). VTE recurrence was 3% among COVID-19 patients and 5.4% among surgical patients, with no significant differences (p = 0.364). The incidence rate of recurrent VTE was 1.25 per 1000 person-months in COVID-19 patients and 2.29 person-months in surgical patients, without significant differences (p = 0.29). In the multivariate analysis, COVID-19 was associated with higher mortality (HR 2.34; 95% CI 1.19-4.58), but not with a higher risk of recurrence (HR 0.52; 95% CI 0.17-1.61). No differences were found in recurrence in the multivariate competing risk analysis (SHR 0.82; 95% CI 0.40 - 2.05). Conclusions: In patients with COVID-19 and surgery-associated VTE, the risk of recurrence was low, with no differences between both groups.

Risk of thrombosis recurrence among patients with COVID-19 and surgery-associated venous thromboembolism.

INTRODUCTION: Recent surgery is a well-known major transient risk factor for venous thromboembolism (VTE) due to the low risk of VTE recurrence after anticoagulation is discontinued. On the other hand, the risk of VTE recurrence among patients with COVID-19-associated VTE is unknown. This study aimed to compare the risk of VTE recurrence between patients with COVID-19- and surgery-associated VTE. METHODS: A prospective observational single-center study was performed including consecutive patients diagnosed with VTE in a tertiary hospital from January 2020 to May 2022 and followed up for at least 90 days. Baseline characteristics, clinical presentation, and outcomes were assessed. The incidence of VTE recurrence, bleeding, and death was compared between both groups. RESULTS: A total of 344 patients were included in the study: 111 patients with surgery-associated VTE and 233 patients with COVID-19-associated VTE. Patients with COVID-19-associated VTE were more frequently men (65.7% vs 48.6%, p =  0.003). VTE recurrence was 3% among COVID-19 patients and 5.4% among surgical patients, with no significant differences (p =  0.364). The incidence rate of recurrent VTE was 1.25 per 1000 person-months in COVID-19 patients and 2.29 person-months in surgical patients, without significant differences (p =  0.29). In the multivariate analysis, COVID-19 was associated with higher mortality (HR 2.34; 95% CI 1.19-4.58), but not with a higher risk of recurrence (HR 0.52; 95% CI 0.17-1.61). No differences were found in recurrence in the multivariate competing risk analysis (SHR 0.82; 95% CI 0.40-2.05). CONCLUSIONS: In patients with COVID-19 and surgery-associated VTE, the risk of recurrence was low, with no differences between both groups.

Monitoring anti-Xa levels in patients with cancer-associated venous thromboembolism treated with bemiparin.

OBJECTIVE: To analyze the relationship between therapeutic (weight-adjusted) dose of bemiparin and anti-Xa activity in patients with venous thromboembolism (VTE) and cancer in comparison with a cohort of patients with VTE without cancer, and its relationship with outcomes. MATERIALS AND METHODS: This is a prospective cohort study that comprised a cohort of patients with cancer-associated VTE and a cohort of non-cancer patients with VTE, all of them treated with bemiparin. The ethics committee approved the study and informed consent was obtained from the patients. RESULTS: One hundred patients were included (52 with cancer and 48 without cancer), with a median follow-up of 9.8 months. Mean anti-Xa activity was 0.89 (± 0.33) UI/mL in oncological patients and 0.83 (± 0.30) UI/mL in non-cancer patients (mean difference - 0.05 95% CI - 0.18; 0.06). A multiple linear regression model showed that anti-Xa peak was associated with the dose/kg independently of possible confounding variables (presence of cancer, age, sex and eGFR-estimated Glomerular Filtration Rate), in a way that for every 1 UI of dose/kg increase, the anti-Xa peak activity increased 0.006 UI/mL (95% CI 0.003; 0.009) (p < 0.001). The predictive capacity of anti-Xa peak in the oncology cohort showed an area under the ROC curve of 0.46 (95% CI 0.24-0.68), 0.70 (95% CI 0.49-0.91) and 0.74 (95% CI 0.44-0.94) for death, first bleeding and recurrence of VTE, respectively, and none was statistically significant. CONCLUSION: In patients with venous thromboembolism treated with bemiparin, anti-Xa levels were not influenced by the presence of cancer.

Massive generalized crystal-storing histiocytosis associated with extracellular crystalline nephropathy: clinical, immunohistochemical, and ultrastructural studies of a unique disorder and review of the literature.

Crystal-storing histiocytosis (CSH) is a rare disorder characterized by the accumulation of nonneoplastic histiocytes containing intracytoplasmic crystallized immunoglobulins. In most cases, there is an associated underlying lymphoplasmacytic neoplasm expressing Ig kappa light chain. About 131 cases of CSH have been identified. There is a localized and a generalized form of CSH and it can involve several sites including bone marrow, lungs, lymph nodes, liver, spleen, gastrointestinal tract, and kidney. Generalized CSH is less frequent and involves multiple organs and tends to have a worst prognosis than localized CSH. Around 20 cases of renal involvement in CSH have been reported so far. Paraprotein-induced crystalline nephropathy can be divided into two categories based on whether the crystals in the kidney are intracellular (including light chain proximal tubulopathy with crystals and CSH) or extracellular (including the crystalline variant of myeloma cast nephropathy and crystalglobulin-induced nephropathy). The former tends to present with slowly worsening kidney dysfunction and generally has a good prognosis, whereas the latter usually presents with rapidly progressive renal failure and is associated with poor renal outcome. We present a case of generalized CSH associated with extracellular crystalline nephropathy with a fulminant and fatal clinical course. Kappa light-chain crystals were found exclusively extracellularly within the tubular lumen, not within the tubular epithelial cells nor the histiocytes, and the massive presence of those precipitates led to the acute renal failure. Consequently, we review the renal involvement in CSH in the literature and discuss the unique mechanism of renal injury in this case.