ABSTRACT

BACKGROUND Cerebral ischemia and hemorrhages were reported to be the main complications of polycythemia vera (PV). The relationship between PV and increased risk of the cerebrovascular events has been established. Some patients with secondary polycythemia have thromboembolic events comparable to those of PV. However, secondary polycythemia that leads to cerebrovascular events is uncommon. CASE REPORT A 35-year-old man without any prior medical history presented with mild clinical acute ischemic stroke and polycythemia. The patient then showed worsening neurological deficits that were later attributed to the concurrent cerebral venous thrombosis, which led to malignant cerebral infarction with hemorrhagic transformation, and subarachnoid hemorrhage. His polycythemia appeared to be secondary to bacterial infection. The treatments for the secondary polycythemia were first phlebotomy and intravenous hydration, followed by intravenous broad-spectrum antibiotics. PV was excluded because the JAK2 V617F mutation was absent, the patient's peripheral blood smear suggested secondary polycythemia due to bacterial infection, and there were improvements in hemoglobin, erythrocyte count, and hematocrit after intravenous antibiotics. At the 1-month follow-up, he was moderately dependent, and hemoglobin, erythrocyte count, and hematocrit were within normal limits, without receiving any further phlebotomy or cytoreductive agents. CONCLUSIONS This case highlights the plausible causation of secondary polycythemia that could lead to concomitant cerebral thrombosis and hemorrhagic events. The diagnosis of cerebral venous thrombosis should be considered in a patient who presents with headache, focal neurological deficits, polycythemia, and normal head computed tomography scan.

PMID:37838828 | PMC:PMC10584197 | DOI:10.12659/AJCR.941507

07:11

PubMed articles on: Cancer & VTE/PE

Causal effect of atrial fibrillation on pulmonary embolism: a mendelian randomization study

J Thromb Thrombolysis. 2023 Oct 15. doi: 10.1007/s11239-023-02903-w. Online ahead of print.

ABSTRACT

Atrial fibrillation (AF) can increase thrombosis, especially arterial thrombosis, and some studies show that AF patients have a higher risk of developing pulmonary embolism (PE). The objective of our study is to investigate whether there is a direct causal effect of AF on PE. A two-sample Mendelian randomization (MR) approach was utilized to determine whether there is a causal relationship between AF and PE. European population-based consortia provided statistical data on the associations between Single Nucleotide Polymorphisms (SNPs) and relevant traits. The AF dataset was obtained from genome-wide association studies (GWAS) comprising 60,620 cases and 970,216 controls, while a GWAS of 1846 cases and 461,164 controls identified genetic variations associated with PE. Estimation of the causal effect was mainly performed using the random effects inverse-variance weighted method (IVW). Additionally, other tests such as MR-Egger intercept, MR-PRESSO, Cochran's Q test, "Leave-one-out," and funnel plots were conducted to assess the extent of pleiotropy and heterogeneity. Using 70 SNPs, there was no evidence to suggest an association between genetically predicted AF and risk of PE with multiplicative random-effects IVW MR analysis (odds ratio = 1.0003, 95% confidence interval: 0.9998-1.0008, P = 0.20). A null association was also observed in other methods. MR-Egger regression and MR-PRESSO respectively showed no evidence of directional (intercept, - 2.25; P = 0.94) and horizontal(P-value in the global heterogeneity test = 0.99) pleiotropic effect across the genetic variants. No substantial evidence was found to support the causal role of AF in the development of PE. Causal effect of atrial fibrillation on pulmonary embolism: a Mendelian randomization study. AF atrial fibrillation, PE pulmonary embolism, GWAS genome-wide association studies, SNPs single nucleotide polymorphisms, OR odds ratio, CI confidence interval.

PMID:37839022 | DOI:10.1007/s11239-023-02903-w

07:11

PubMed articles on: Cancer & VTE/PE

Persistent underuse of extended venous thromboembolism prophylaxis in patients undergoing major abdominal cancer operations

J Surg Oncol. 2023 Oct 6. doi: 10.1002/jso.27473. Online ahead of print.