Magnesium deficiency during lactation as a precipitant of ventricular tachyarrhythmias

A young ICD recipient with a history of syncope and idiopathic polymorphic ventricular tachycardia/ventricular fibrillation presented after an ICD discharge. She had delivered her first child 8 days prior to the event and she had been lactating. Numerous short runs of polymorphic ventricular tachycardia/ventricular fibrillation resolved with aggressive replacement of magnesium and elimination of breast-feeding.     

Anticardiolipin antibodies as a risk factor for venous thromboembolism in a population-based prospective study

Anticardiolipin antibodies, one of the family of 'antiphospholipid' antibodies, increase the risk of venous thromboembolism in the presence of autoimmune disease. Our objective was to determine prospectively whether there is a positive association between anticardiolipin antibodies and venous thromboembolism in ostensibly healthy adults. We conducted a nested case-control study (n = 317 patients and n = 655 control subjects) in a longitudinal study of over 20 000 participants. Baseline (prediagnosis) anticardiolipin IgG and IgM antibodies were assessed by enzyme-linked immunoassays. Venous thromboembolism was validated using standardized criteria for venous thrombosis and pulmonary embolism. There was no association between anticardiolipin antibodies and subsequent venous thromboembolism occurrence, overall or in any subgroup. For example, the multivariate-adjusted relative risk was 0.88 (95% confidence interval, 0.43, 1.78) for greater than versus less than the 95th percentile of anticardiolipin IgG. In conclusion, in this general population sample, an elevated anticardiolipin antibody level was not a risk factor for venous thromboembolism.     

Incidence of malignancy in complex cystic renal masses (Bosniak category III): should imaging-guided biopsy precede surgery?

OBJECTIVE: Complex indeterminate renal cystic masses (Bosniak type III) can have benign and malignant causes and have been traditionally considered surgical lesions. We sought to determine the incidence of malignancy and to assess a possible role for imaging-guided biopsy for this category of renal masses. MATERIALS AND METHODS: Three hundred ninety-seven renal biopsies were performed at our institution between 1991 and 2000. Between January 1997 and August 2000, 28 Bosniak category III lesions, based on established CT imaging criteria on helical CT scans, were identified for analysis. The incidence of malignancy, based on surgical pathology or imaging follow-up and percentage of lesions proceeding to surgery, among these 28 lesions, was determined. The surgical results were correlated with the biopsy findings. RESULTS: Of the 28 biopsied category III lesions, 17 (60.7%) were malignant (16 renal cell carcinomas and one lymphoma), and 11 (39.3%) were benign (six hemorrhagic cysts, three inflammatory cysts, one metanephric adenoma, and one cystic oncocytoma). Seventeen of the 28 lesions (16 renal cell carcinomas and one inflammatory cyst) had surgical resection after the biopsy. All resected lesions had pathologic diagnoses identical to the percutaneous imaging-guided biopsy results. The remaining 11 patients who had undergone nonsurgical biopsies had radiologic follow-up for a minimum of 1 year, with benign lesions showing no interval change. CONCLUSION: Renal biopsy and radiologic follow-up were useful in identifying nonmalignant lesions in complex cystic renal masses and avoided unnecessary surgery in 39% of patients.     

Psychiatric comorbidity and physicians with substance use disorders: a comparison between the 1980s and 1990s

The assessment and treatment of physicians with substance use disorders has been of considerable interest over the past twenty years. This study compares two cohorts of addicted physicians treated at a single program. Data from 101 physicians treated during 1985 to 1987 were compared with 73 physicians treated from 1995 to 1997. Although the cohorts were similar on demographic, physician specialty, and drug of choice variables, psychiatric comorbidity was significantly more prevalent in the later sample.     

Short-term variability in the measurement of plasma homocysteine, fasting and post-methionine loading

OBJECTIVES: Hyperhomocysteinemia is associated with premature cerebral, peripheral and coronary vascular disease. Evaluation of the significance of changes in plasma total homocysteine (tHcy) results obtained by analysis of serial specimens may be accomplished only by taking into account biologic (between-person and within-person) as well as analytical variation. Since the repeatability of a measurement significantly determines our ability to associate tHcy level with the presence of disease, this study was performed to evaluate various components of variation in tHcy values. DESIGN AND METHODS: We report the within-person, between-person, and methodological variability of tHcy, both fasting and postmethionine load (PML) values, in 20 healthy volunteers from whom samples were drawn weekly for 4 weeks. RESULTS: The short-term reliability coefficient (R) was 0.72 for fasting tHcy and 0.83 for PML tHcy. CONCLUSIONS: The current study demonstrates for the first time that the short-term reliability coefficient for PML tHcy is relatively high (0.83), suggesting that an individual's PML tHcy, like fasting tHcy, is relatively constant over at least one month, and that a single measurement should provide a reasonable characterization of an individual's PML tHcy concentration.     

Migraine and masticatory muscle volume, bite force, and craniofacial morphology

The purpose of this investigation was to compare the masticatory muscle volume, bite force, and craniofacial morphology of migrainous subjects with age- and sex-matched controls. Ten adult dentate migraineurs were matched with 10 dentate age- and sex-matched controls. The groups consisted of nine women and one man (mean age, 43 years; range, 29 to 51 years). Volumetric analysis of the masseter and medial pterygoid muscles was performed using magnetic resonance imaging. Craniofacial morphology was analyzed from standard cephalometric radiographs using 30 angular and linear variables. Recordings of bite force were made using a strain gauge transducer. There was a significant difference in the volume of both masseter and medial pterygoid muscles between the two subject groups (P<.0001), with the muscles of the migraineurs nearly 70% larger. The migraineurs recorded significantly higher maximal bite forces (P<.0001) than did the controls. No significant differences for any craniofacial morphological measurement were demonstrated between the two groups. It was concluded that the migraineurs had larger masseter and medial pterygoid muscle volumes, and greater bite forces than the controls, which could not be explained by any change in craniofacial morphology.