Anti-Xa activity after enoxaparin prophylaxis in hospitalized patients weighing less than fifty-five kilograms.

INTRODUCTION: Low-molecular-weight heparins are commonly used for the prophylaxis of thromboembolic disease. In contrast to therapeutic doses, recommended prophylactic doses are fixed (i.e., 40 mg/day enoxaparin). Dosing of patients with extreme body weights has not been well studied, especially dosing of low weight patients. OBJECTIVES: To establish the anti-Xa activity that results from 40 mg/day enoxaparin in inpatients with body weight ≤ 55 kg. PATIENTS/METHODS: Cross-sectional study including inpatients older than 18 years, with body weight ≤ 55 kg, and whose treating physician found indication for 40 mg/day enoxaparin. We excluded patients with renal failure and those using oral anticoagulants. Anti-Xa activity was measured 3 hours after the second dose of enoxaparin. Statistical analyses were conducted to determine the effect of body weight on anti-Xa levels. RESULTS: Average age was 72.5 years (interquartile range, 30) and median body weight was 49.7 kg (interquartile range, 7). Twenty-five percent of patients weighed ≤ 45 kg, 37.5% weighed 46-50 kg, and 37.5% weighed 51-55 kg. The mean anti-Xa activity was 0.54±0.18IU/ml, and 60% of the patients exhibited activity ≥0.5 IU/ml. Weight and anti-Xa activity inversely correlated (Spearman's rho=-0.428, p=0.001). Patients weighing ≤ 45 kg exhibited higher anti-Xa activity (0.61±0.18 IU/ml, p=0.008) than heavier patients and an odds ratio of 8 for anti-Xa level ≥0.5IU/ml (95% CI: 1.42-45.06). CONCLUSIONS: Anti-factor Xa activity rises significantly when body weight decreases. Patients of low weight, especially those weighing <45 kg, exhibited an anti-Xa activity higher than the desired range for thromboembolic prophylaxis.

[Reproductive risk factors and uterine cervix cancer in Mexico City]. / Factores de riesgo reproductivo y cáncer cérvico-uterino en la Ciudad de México.

An epidemiological case control study nested in the Early Cancer Detection program of the Health Ministry in Mexico City was carried out to evaluate the principal reproductive risk factors associated with uterine cervix cancer. Information from 12,741 gynecological cytologies reported to the National Cancer Registry, during the period between January 2 to March 31, 1987 was studied. In this population group the most important reproductive risk factors associated with uterine cervix cancer were: multiple births (seven or more births, OR = 3.24, IC 95% = 2.20-4.76), initiation of active sex life before 14 years (OR = 1.53, 95% IC = 1.13-2.08) and late menarche (in the group with menarche after 17 year of ages OR = 3.22, 95% IC = 1.06-9.77). In relation to the Early Cancer Detection program, an important number of women made use of the program when they showed symptoms. The prevalence among women who had at least one symptom was 43.09 per cent. Women with a tumor at the cervical level at the time of the cytology were 7.76 times more likely to have of uterine cervix cancer (95% IC = 4.84-13.15). Symptoms such as dysfunctional bleeding (OR 2.79, IC 95% = 1.90-4.12), metrorrhagia (OR 2.66, 95% IC 1.83-3.86) and bloody leukorrhea (OR 2.64, 95% IC 2.05-3.38) can be relevant findings in women at high risk. The attributable fraction of higher exposure in the presence of gynecological signs and symptoms is the cervical tumor, with 87.46 per cent.(ABSTRACT TRUNCATED AT 250 WORDS)

A large phenotypic sib-sib discordance for the Rh blood system. A possible new feto-maternal compatibility system.

A large sib-sib phenotypic discordance for the Rh system has been found in a longitudinal follow-up study on growth and development. Sibs born no more than 3 years later than their respective indexes show a significant tendency to have a different phenotype from that of their indexes. The hypothesis that distortion is due to eggs or fetal loss finds support in the existence of increased time intervals between indexes' and sibs' births in those cases in which the losses were suspected. Two groups of index families made according to the presence or absence of the cde haplotype in their genotype show important differences in segregation and reproductive patterns. The observed distortions cannot be explained by the differences in known antigenic Rh specificities. The existence of a new feto-maternal compatibility system would better fit these facts and would also allow the reinterpretation of several distortions associated with Rh described in the literature that have never been satisfactorily explained.