Biomedical subjects

A Lubetsky

Publications and source records attributed to A Lubetsky.

25 records · Page 2Linked to original sources

PubMed1999

Does thrombophilia play an aetiological role in Legg-Calvé-Perthes disease?

Heritable thrombophilic disorders have been proposed as one of the causes for Legg-Calvé-Perthes disease. A total of 62 patients diagnosed with this disease between 1988 and 1997 and 50 controls were screened for thrombophilia. The incidence and relationship of thrombophilia to the severity of the disease were evaluated. One patient and none of the controls had protein S deficiency. One of the control group and one of the patients had protein C deficiency with the latter child also having a combined deficiency with a mutant factor V gene. The number of children with a mutant factor V gene, protein C deficiency, who were homozygous for the C 677T polymorphism of methylenetetrahydrofolate reductase or were heterozygous for mutant G20210A prothrombin did not differ statistically in the study and the control groups. No patient had antithrombin deficiency or positive lupus anticoagulant. We found no correlation between thrombophilia and the extent of the disease. The most common risk factors for arteriovenous thromboembolism showed no statistical significance in our patients compared with the control group or with the general population. These data do not confirm an aetiological role for thrombophilia in Perthes' disease.

Child↗

PubMed1999

Safety and efficacy of continuous infusion of a combined factor VIII-von Willebrand factor (vWF) concentrate (Haemate-P) in patients with von Willebrand disease.

We studied the safety and efficacy of treatment with continuous infusion of a von Willebrand factor (vWF) concentrate Haemate-P in patients with von Willebrand disease (vWD). Three patients with mild and 5 patients with severe forms of vWD, were treated with continuous infusion of Haemate-P by minipump. The indications for treatment were: to prevent bleeding during 9 surgical procedures or 1 vaginal delivery in 6 patients and to treat 2 bleeding episodes in 2 patients. The patients were monitored daily for factor VIII (FVIII:C) and ristocetin cofactor (vWF: RCo) levels and the infusion rate was adjusted to maintain the desired therapeutic level of vWF:RCo. The treatment was effective in preventing surgical bleeding and controlling bleeding episodes. All factor VIII:C and most of the vWF:RCo levels measured during the study period were above the target therapeutic levels. A significant decrease in clearance of FVIII:C and vWF:RCo was observed over the treatment period. Haemate-P consumption averaged 24.3+/-7.9 vWF:RCo U/kg/day which is approximately half the expected dose had intermittent bolus injections been used. We suggest that continuous Haemate-P infusion is superior to intermittent bolus injections for the treatment of vWD patients by virtue of its efficiency, simplicity and considerable savings.

Adolescent↗

PubMed1999

Vitamin K intake and sensitivity to warfarin in patients consuming regular diets.

The effect of dietary vitamin K intake on warfarin sensitivity is known only from case reports and few small clinical studies. We followed 50 patients commencing warfarin and consuming their regular diets (for 8 weeks) to study this relationship. A one-week recall dietary questionnaire was completed at weeks 2 and 8. Daily intake of nutrients and vitamin K was calculated from standard tables. Warfarin sensitivity index (WSI) was defined as final INR/final warfarin dose (mg/day/m2 of body surface area) (week 8). Vitamin K intake was 17-974 (median: 179) microg/day. Median WSI was 0.82 (0.31-4.47). A WSI value of 1.1 significantly separated excess (>250 microg/day) from normal (<250 microg/day) vitamin K consumers (16/18 vs. 15/32, respectively, p <0.01). The former had lower day 5 INR (median: 1.9 vs. 3.0, p <0.001), needed more warfarin to achieve INR > or =2.0 (32.0+/-9.2 mg vs. 25.4+/-6.4 mg, p = 0.009) and required a higher maintenance steady state warfarin dose (5.7+/-1.7 mg/day vs. 3.5+/-1.0 mg/day, p <0.001). We conclude that in 32% (16/50) of anticoagulated patients under usual dietary conditions sensitivity to warfarin is decreased by vitamin K intake > or =250 microg/day.

Adult↗

PubMed1998

Cone and platelet analyser (CPA): a new test for the prediction of bleeding among thrombocytopenic patients.

The risk of bleeding among thrombocytopenic patients was evaluated using our new cone and platelet analyser (CPA) test. Using this test, adherence of platelets was quantitated on extracellular matrix and expressed as percent of surface coverage (SC) and the average size (AS) of aggregates. 42 thrombocytopenic patients with ITP (n=23), post chemotherapy (n= 12) and others (n= 7) were tested over a total of 82 visits. On each visit, complete blood count and CPA tests were performed and patients were evaluated for evidence of bleeding (found in 40 visits). Bleeding patients had significantly lower platelet counts (27.4 +/- 22.0 v 47.1 +/- 21.0 x 10(9)/l), lower haematocrit values (30.2 +/- 8.1 v 35.2 +/- 6.6%), lower MPV (6.83 +/-1.89 v 8.98 +/- 1.13 fl), and lower SC (4.87 +/- 3.95 v 10.33 +/-5.48%) and AS (33.99 +/- 14.94 v 52.9 +/- 24.34 microm2). Univariate analysis yielded platelet count < or =20.0 x 10(9)/l, MPV < or =8 fl, haematocrit <35%, SC <5%, AS< or =40 microm2 as significantly associated with bleeding, whereas only MPV and SC were associated with bleeding (OR 6.95, CI 2.25-21.46 and OR 4.27, CI 1.29-14.16, respectively) by multivariate analysis. When taken together, 21/22 of patients (95%) with both low SC (<5%) and low MPV (<8.0 fl) had bleeding symptoms, whereas only 9/43 (21%) patients with both these parameters above these values experienced bleeding symptoms. We conclude that the CPA test and the parameter SC (<5%) together with MPV (< or =8 fl) might be used as independent predictors of bleeding in the management of thrombocytopenic patients.

Adolescent↗

PubMed1992

The effect of the plasma levels of proteins C and S on the prediction of warfarin maintenance dose requirements.

OBJECTIVE: Determination of the effects of the vitamin K-dependent anticoagulants, proteins C and S, on warfarin dose requirements and on the prediction error of a bayesian warfarin dose predicting program. METHODS: Patients in the study were consecutive inpatients (n = 18) starting treatment with warfarin who were monitored as outpatients for 4 weeks. The following measurements were taken: repeated (n = 8) prothrombin times, expressed as the international normalized ratio (INR), plasma protein C and S antigen levels (percentage of pooled normal plasma), demographic, clinical and biochemical variables. RESULTS: Maintenance doses (adjusted to INR 2.5) were 6.7 +/- 3.4 mg/day. Protein C decreased to 56.9% +/- 15.3%, protein S to 63.7% +/- 17.3%, INR increased to 2.46 +/- 0.14. Prediction error decreased from 2.84 +/- 2.0 mg/day to 0.95 +/- 0.78 mg/day. Protein C accounted for only 4.2% of the mean maintenance dose but protein C and S levels accounted for 31% of the mean dose prediction error. CONCLUSION: Protein C and S levels affect warfarin doses and predictions significantly but not to a clinically meaningful degree.

Adolescent↗

PubMed1992

[Atrial septal defects and embolic stroke in young adults].

The mechanism of embolic stroke in young adults remains unidentified in about 35% of cases. In recent years defects in the atrial septum have been described as an important route for cerebral and retinal embolism. These include classical atrial septal defect and patent foramen ovale, as well as the less well-recognized entity of atrial septal aneurysm, with or without interatrial communication. The combined incidence of these defects in the general population is between 20-35%. The introduction of transesophageal echocardiography and the use of echogenic contrast have lead to significant improvement in identification. We describe 3 patients in whom atrial defects were identified as possible routes for cerebral embolism: The first presented with recurrent stroke and combined atrial septal aneurysm and patent foramen ovale. In the second, patent foramen ovale was found in a patient with 2 prosthetic values. The third was a soldier in whom patent foramen ovale was found following transient loss of consciousness. Based on our modest experience and review of the literature we believe that transesophageal and contrast echocardiography should be performed in every young patient with unexplained cerebral ischemia.

Adult↗

PubMedDate not supplied

The 1226G (N370S) Gaucher mutation among patients with Legg-Calve-Perthes disease.

Legg-Calve-Perthes disease (LCPD) is an avascular necrosis of the femoral head with an annual incidence of 5-15/100,000. The estimated incidence of Gaucher disease, a lysosomal recessive storage disease, is 1:850, with a carrier rate of 1:17.5 for the 1226G (N370S) mutation among Ashkenazi Jews in whom there is a predilection. Since clinical and radiological findings of avascular hip necrosis due to either Gaucher disease or LCPD may be indistinguishable, misdiagnosis may occur. The purpose of this study was to evaluate the incidence of 1226G Gaucher mutation in a cohort of radiologically confirmed LCPD patients (diagnosed 1986-2000) in Israel. Enzyme assay was performed for confirmation of affected versus carrier status in patients with the 1226G mutation. In all, 78 LCPD patients, 86% males, 51% with severe bone disease, were studied. Family history was negative for Gaucher disease. Ethnic origin was 39% Ashkenazi Jewish, 6% Arab, and 55% other ethnicities. One Ashkenazi Jewish LCPD patient was homozygous for the 1226G mutation, and 4 LCPD patients were carriers: 3 Ashkenazi Jewish and 1 Arab patient. The frequency of the 1226G mutation among the LCPD patients was increased relative to historical Ashkenazi Jewish Israeli controls (P = 0.01). Since Gaucher disease may be misdiagnosed as LCPD, glucocerebrosidase enzyme testing is recommended among Ashkenazi Jewish children diagnosed with LCPD.

Clinical Enzyme Tests↗