Prevalence of upper extremity deep venous thrombosis diagnosed by color Doppler duplex sonography in cancer patients with central venous catheters.

OBJECTIVE: The purpose of this study was to review the literature concerning upper extremity deep venous thrombosis (UEDVT) diagnosed by color Doppler duplex sonography (CDDS) in cancer patients with indwelling central venous catheters (CVCs). METHODS: From computerized databases (MEDLINE and Ovid), relevant publications regarding CDDS of the upper limb veins in cancer patients with CVCs were reviewed. RESULTS: Patients with malignancy have a higher rate of thrombosis, which is increased by the presence of CVCs. Screening CDDS in asymptomatic patients showed CVC-related UEDVT in 11.7% to 44% of patients. In symptomatic cancer patients, the range was similar to the asymptomatic ones, 6.7% to 48%. The presence of a CVC almost doubled the incidence of UEDVT in symptomatic patients. Color Doppler duplex sonography is an accurate examination for the diagnosis of UEDVT, with sensitivity ranging from 78% to 100% and specificity ranging from 82% to 100%. The main obstacle for the diagnosis of UEDVT is the presence of overlying bones, making it difficult to visualize and impossible to directly assess by compression techniques. Color and spectral Doppler sonography and the use of small transducers aid in the diagnosis. When several parameters are evaluated in combination, CDDS is a reliable method for diagnosing CVC-related thrombosis. CONCLUSIONS: Great variability in the prevalence of catheter-related thrombosis in cancer patients has been reported, although it is uniformly higher compared with patients without cancer. Color Doppler duplex sonography is the modality of choice for the diagnosis of CVC-related UEDVT in symptomatic cancer patients and for screening for asymptomatic thrombosis in this specific population.     

Enoxaparin-induced alopecia in patients with cerebral venous thrombosis

OBJECTIVE: To report three cases of alopecia induced by the anticoagulant enoxaparin in cerebral venous thrombosis (CVT) patients. CASE SUMMARY: Three female patients were treated initially with direct intrasinus urokinase, and then followed by low-molecular-weight heparin (LMWH) enoxaparin at 1 mg/kg given subcutaneously twice daily for 3 weeks. It was switched to oral anticoagulant warfarin at 5 mg daily for another 6 months. Nearly 3 weeks after the initiation of anticoagulation, all of the three patients complained of excessive hair loss with large areas of patchy, non-scarring alopecia. Hair growth returned to normal within 1 month after the completion of enoxaparin. DISCUSSION: Unfractionated heparin remains the first-line treatment of CVT because of its efficacy, safety and feasibility. Alopecia has been reported as a side effect of LMWHs dalteparin and tinzaparin. The pattern of hair loss, telogen effluvium, involves the induction of the hair follicle into a resting phase without apparent pathologic implication. In addition, this article also reviewed other medications taken by the patients that are possibly associated with hair loss. CONCLUSION: From the review of literature, there is no report of alopecia caused by urokinase. Using the Naranjo ADR Probability Scale, a score of 6 suggests that enoxaparin was the probable cause of alopecia in our three patients. This report introduces evidence of alopecia as a probable side effect of enoxaparin, but stresses the efficacy and safety of LMWH. As this is not a life-threatening disorder, we hope to increase the awareness of pharmacists and clinicians to this relatively rare but important side effect.     

Genetic determinants of heritable venous thrombosis: genotyping methods for factor V(Leiden)A1691G, methylenetetrahydrofolate reductase C677T, prothrombin G20210A mutation, and algorithms for venous thrombosis investigations.

OBJECTIVES: To implement cost effective and clinically relevant thrombophilic genotyping and homocysteine analysis in our coagulation laboratory. METHODS: We describe genotyping assays for three of the genetic defects associated with hereditary thrombosis: factor V(Leiden) A1691G, methylenetetrahydrofolate reductase C677T, and prothrombin gene G20210A. A second confirmatory assay for factor V(Leiden) using allele specific oligonucleotide polymerase chain reaction is also presented. We suggest an algorithm for the rational integration of the traditional assays routinely used to investigate venous thrombosis with genotyping and plasma homocysteine measurements. RESULTS: These polymerase chain reaction based assays were designed to be performed under identical reaction conditions, permitting simultaneous setup, amplification, digestion, and analysis. CONCLUSIONS: The three genotyping assays presented are robust and relatively easy to perform. Use of an algorithm will ensure efficient resource utilization and minimize unnecessary testing.     

A guide for diagnosis of patients with arterial and venous thrombosis.

Inasmuch as coagulation laboratories are involved in providing a diagnosis for underlying causes of venous and arterial thrombosis, we present a comprehensive review of the biological properties and functions of the components of the hemostatic system as they relate to the diagnosis of arterial and venous thrombosis. Moreover, as coagulation laboratories are necessary to evaluate the success of initial treatment modalities and to provide guidance for supplemental therapeutic intervention, we include information on antiplatelet and antithrombotic therapy. Included in clinical coagulation testing are assays that evaluate the potential of blood to form clots and tests for platelet numbers and platelet functions. Clot-based assays directly detect the biological activity of procoagulant factors and fibrinogen; chromogenic substrate assays evaluate proteolytic activities of clotting as well as fibrinolysis enzymes; and specific antibodies measure the concentrations of coagulation and fibrinolysis enzymes in plasma. Genetic testing is rapidly becoming incorporated into the clinical routine. The prothrombin time (PT), activated partial prothrombin time (APTT), and thrombin time (TT) are screening assays that measure the clotting times of recalcified whole blood or platelet-poor plasma. In addition to their function as screening assays, PT, APTT, and TT are the backbone of all the specialized clot-based assays for factor activities and for the indirect measurement of inhibitory antithrombin and protein C activities. Molecular markers related to hemostasis and fibrinolysis consist of proteins or peptides that indicate an ongoing physiological or abnormal process related to clot formation, thrombosis, vascular damage, or drug effect. Molecular markers are currently identified by means of specific antibodies prepared against them. The list of hemostatic molecular markers is rapidly growing. Most of the assays developed for molecular marker measurement, with the notable exception of the d-dimer assay, are typically used in clinical research.     

Mesenteric venous thrombosis.

BACKGROUND: Mesenteric venous thrombosis is an uncommon but often lethal form of intestinal ischemia. METHODS: We reviewed pertinent literature on mesenteric venous thrombosis using MEDLINE search. RESULTS: We found that previous abdominal surgery and hypercoagulable states are the most common conditions associated with mesenteric venous thrombosis. The symptoms and signs related to mesenteric venous thrombosis are not specific. In the majority of cases, the diagnosis is established by a high index of clinical suspicion and noninvasive imaging techniques. Immediate operation is indicated if signs of peritonitis or intestinal infarction are present. Administration of heparin is beneficial for reducing recurrence and mortality. CONCLUSION: Clinicians should consider the possibility of acute mesenteric venous thrombosis when faced with a patient having abdominal pain out of proportion to the physical findings and with a negative workup for the common causes of abdominal pain.     

Deep venous thrombosis.

Venous thrombosis involving the deep veins is a major US health problem that affects over 2.5 million people annually. The most serious complication of a deep venous thrombosis (DVT) is pulmonary embolism (PE), which is associated with 50,000 to 200,000 deaths each year. DVT and PE are often silent and difficult to detect by clinical examination; however, DVT rarely occurs in the absence of risk factors. This article reviews normal venous anatomy and discusses the etiology of DVT, its clinical manifestations, and diagnosis. Then it reviews treatment of DVT, highlighting the nurse's role. A discussion of DVT prophylaxis based on patient risk follows.     

Lower extremity deep venous thrombosis in cancer patients: correlation of presenting symptoms with venous sonographic findings.

We sought to determine how rates of sonographically detected deep venous thrombosis correlate with presenting symptoms in cancer patients. We performed venous sonography in 588 cancer patients with clinically suspected lower extremity deep venous thrombosis. Results were correlated with clinical findings. Deep venous thrombosis was diagnosed in 32% of patients with unilateral lower extremity symptoms and in 17% of patients with bilateral symptoms. Patients with unilateral symptoms of pain and swelling, swelling alone, or pain alone had significantly different rates of deep venous thrombosis (47%, 31%, and 16%, respectively). In patients with bilateral leg symptoms, deep venous thrombosis was significantly more likely when symptoms were not bilaterally symmetric.     

恶性肿瘤患者合并下肢深静脉血栓的介入治疗

目的 研究在恶性肿瘤患者合并下肢深静脉血栓中置入下腔静脉滤器预防肺栓塞并进行溶栓的效果。方法 回顾性分析 2003年6月至2007年4月，经病理学或细胞学确诊为恶性肿瘤，并于治疗前存在下肢深静脉血栓的20例患者，安放下腔静脉滤器后肺栓塞的发生情况，12例保留导管溶栓治疗。结果 下腔静脉滤器全部置入成功，溶栓治疗有效。随访1--24个月，滤器无移位，无肺栓塞发生。结论 对恶性肿瘤合并下肢深静脉血栓形成的患者放置下腔静脉滤器 可较好地预防肺栓塞发生。     

Prophylaxis of catheter-related venous thrombosis in cancer patients

BACKGROUND: The use of indwelling central venous catheters (CVCs) for chemotherapy delivery is common practice in cancer patients. Central venous lines facilitate ease of blood drawing along with administration of blood products and various other therapies. Significant risks, however, include infection and catheter-related thrombosis. Several attempts have been investigated to reduce CVC-associated thrombosis, in particular anticoagulation strategies. Given the lack of clear efficacy, there is at present no recommendation for the use of prophylactic anti-coagulation in patients with solid malignancy and an indwelling CVC. MATERIALS AND METHODS: This paper reviews recent given recommendations based on controlled trials.     

A detailed analysis of equivocal duplex findings in patients with suspected deep venous thrombosis.

OBJECTIVE: To analyze equivocal duplex findings in patients with clinically suspected deep venous thrombosis and thus to increase the diagnostic utility of color duplex sonography in this category of patients. METHODS: Phlebography was requested in a series of 102 consecutive patients with inconclusive duplex findings. These patients were, according to the duplex findings only, subdivided into having low, intermediate, and high probability of deep venous thrombosis. RESULTS: Phlebographywas attempted in 71 cases and successfully performed in 49. The remaining 53 patients were prospectively followed clinically for 6 months. Phlebography showed deep venous thrombosis in 1 of 63 patients in the group with low probability, 3 of 31 in the intermediate group, and all of the 8 patients with high probability. Twenty-two (31%) of the 71 attempted phlebographic examinations were nondiagnostic. None of the patients in the follow-up group had any thromboembolic complications. CONCLUSIONS: Even if a duplex examination is equivocal, it is still possible to extract clinically useful information by categorizing the duplex results into subgroups with low, intermediate, and high probability of deep venous thrombosis. This can have implications for the diagnostic or therapeutic handling of these patients and thus can increase the utility of sonography in patients with inconclusive duplex findings.     

Activation of innate immunity in patients with venous thrombosis: the Leiden Thrombophilia Study.

BACKGROUND: Previous studies have suggested that levels of inflammatory mediators are risk indicators for venous thrombotic disease. We have sought to confirm and extend these findings by measuring plasma tumor necrosis factor (TNF)-alpha, interleukin (IL)-1beta, IL-6, IL-8, IL-10 and IL-12p70 levels in a case-control study for venous thrombotic disease. METHODS: The plasma levels of these inflammatory mediators were measured by flow cytometric analysis using a multiplexed bead assay. Patient and control samples came from the Leiden Thrombophilia Study (474 controls and 474 patients). RESULTS: In a subset of patients and controls inflammatory mediators are detectable in plasma. The crude odds ratios (ORs) associated with the presence of detectable markers were 2.1 [TNF-alpha, 95% confidence interval (CI) 1.1, 3.9], 1.7 (IL-1beta, 95% CI 1.1, 2.9), 2.4 (IL-6, 95% CI 1.9, 5.3), 2.8 (IL-8, 95% CI 1.8, 4.4), 0.8 (IL-10, 95% CI 0.3, 1.8), and 1.3 (IL-12p70, 95% CI 0.9, 2.0). Adjustment for putative confounders did not influence the risk estimates. CONCLUSION: TNF-alpha, IL-6, and IL-8 levels are risk determinants for venous thrombosis. Individuals with detectable levels of either of these mediators in plasma have an OR of about 2. In line with these findings, the odds for the anti-inflammatory cytokine Il-10 tend to be < 1. These results add further evidence for the contention that there is an inflammatory component to venous thrombotic disease and may explain why anti-inflammatory agents such as aspirin may be effective for prevention.     

Deep venous thrombosis associated with heterotopic ossification.

The differential diagnosis of the swollen lower extremity in the patient with spinal cord injury includes deep venous thrombosis, fracture, cellulitis, joint sepsis, heterotopic ossification, hematoma formation, and neoplasm. A patient with an asymmetrically swollen limb who was found to have concurrent ipsilateral acute deep venous thrombosis and active heterotopic ossification is described. The diagnostic workup included various laboratory and radiologic studies. Therapy included anticoagulation with heparin and warfarin. To treat the heterotopic ossification, indomethacin, etidronate, and graded range of motion were used. We learned from this patient and several similar cases that acute deep-venous thrombosis and active heterotopic ossification may occur concurrently, and therapeutic anticoagulation did not lead to bleeding within or around the area of active heterotopic ossification. The possibility of a relationship between heterotopic ossification and deep venous thrombosis is presently being studied at our institution.     

Factor V Leiden with deep venous thrombosis.

Factor V Leiden (FVL) is an autosomal co-dominantly inherited Arg506-->Gly substitution of the activated protein C cleavage site affecting 5% of the Caucasian population. FVL results in impaired anticoagulant function without procoagulant modification. Heterozygotes experience a seven-fold increase in thrombotic events, whereas homozygotes may incur a 50 to 100 fold increase. Even though patients are at increased risk for deep venous thrombi, they experience a smaller risk of pulmonary embolism compared to individuals affected by other coagulopathies.