Small proportions: what to report for confidence intervals?

The original article to which this Erratum refers was published in Pharmacoepidemiology and Drug Safety 2005; 14: 239–247.     

Piperacillin-Tazobactam Pharmacokinetics in Patients With Intraabdominal Infections

Study Objective . To determine the appropriate compartmental and noncompartmental pharmacokinetic parameters for intravenous piperacillin and tazobactam. Design . Sequential selection of patients entered into a randomized, open-label clinical efficacy trial. Setting . Los Angeles County-University of Southern California Medical Center. Participants . Sequential sample of 18 patients admitted for intraabdominal infections and consented into a comparative antibiotic trial. Interventions . Patients received piperacillin 4 g plus tazobactam 500 mg by intravenous intermittent infusion every 8 hours. Measurements and Main Results . The estimated noncompartmental pharmacokinetic parameters (mean ± SD) for piperacillin and tazobactam, respectively, were as follows: maximum concentration in plasma 218.7 ± 48.9 μg/ml and 27.8 ± 9.1 μg/ml; half-life 1.07 ± 0.22 hours and 1.00 ± 0.27 hours; elimination rate constant 0.67 ± 0.13 hr⁻¹ and 0.73 ± 0.18 hr⁻¹; area under the concentration-time curve from zero hour to infinity 288.5 ± 71.25 mg·hr/L and 36.3 ± 9.55 mg·hr/L; total plasma clearance 14.75 ± 3.93 L/hour and 14.78 ± 4.39 L/hour; renal clearance 5.69 ± 1.94 L/hour and 7.85 ± 3.37 L/hour; volume of distribution at steady state 21.00 ± 4.18 L and 22.47 ± 8.27 L; and mean residence time 1.72 ± 0.29 hours and 1.79 ± 0.35 hours. Conclusion . Our findings were similar to those in other surgical patient models. The two-compartmental model best described piperacillin and tazobactam disposition in our patients. Bayesian analyses of the two-compartment models of piperacillin and tazobactam were able to predict trough, peak, and 2-hour postadministration levels without bias.     

Intercellular adhesion molecule‐1 gene polymorphisms in Behçet’s disease

Intercellular adhesion molecule‐1 (ICAM‐1) gene polymorphisms have been implicated in the susceptibility to inflammatory diseases, including multiple sclerosis and inflammatory bowel disease. The expression of both soluble and tissue ICAM‐1 is increased in Behçet’s disease (BD) but the contribution of ICAM‐1 gene polymorphisms to this disease remains unknown. Associations with BD have been reported for genes within the MHC, including HLA‐B51, TNF and MICA, but the role of non‐MHC genes in BD remains largely unexplored. We have investigated the frequency of the R/G 241 and K/E 469 ICAM‐1 gene polymorphisms in 83 patients with BD disease and 103 healthy controls, all of Palestinian and Jordanian descent, and demonstrated an association between BD and the ICAM‐1 E469 allele (P_c = 0.046, OR = 2.1). Among patients, no association was found between the presence of ocular disease and ICAM‐1 polymorphisms. While the functional correlate of this polymorphism remains unclear, this finding indicates that a genetic polymorphism in the ICAM‐1 gene domain, which is independent of the MHC, may contribute to disease.     

Cystic renal melanoma: CT/ultrasound correlation

A new computed tomographic and sonographic appearance of renal metastatic melanoma is described. Bilateral cystic masses with thick walls, many with mural nodules, were noted. Sonography also demonstrated complex echopenic masses with irregularly thickened walls and mural nodules.     

Membership and attendance patterns in Tavistock Clinic general practitioner seminars

Patterns of recruitment and attendance (1951-79) of general practitioners at seminars at the Tavistock Clinic are analysed. Latterly about 40 general practitioners have attended each week; a turnover of about 15 join or leave each year; about 60 per cent stay at least two years and 40 per cent stay over three years. Half come from outside London. The ratio of men and women reflects the prevailing ratio in the profession. Most join five to 10 years after qualifying and younger general practitioners tend to leave early. At least seven per cent of recent members have left general practice; but the proportion involved in training, course organizing and the Royal College of General Practitioners is far above the average for all general practitioners.