Trimethoprim-Sulfamethoxazole Pharmacokinetics during Continuous Ambulatory Peritoneal Dialysis (CAPD)

Ten adult patients on continuous ambulatory peritoneal dialysis (CAPO) received one dose of trimethoprim320 mg (TMP) and sulfamethoxazole 1600 mg (SMX) orally (p.o.), intravenously (i.v.), and intraperitoneally (i.p.) on three separate occasions to characterize the pharmacokinetics of both drugs. Concentrations of both TMP and SMX were measured in serum and dialysate by HPLC to 48 h. Half-life, total body clearance (TBC), and peritoneal clearance (PCI) were determined. The mean half-life of TMP was 28 h, while for SMX it was 12.5 h. Relative to the i.v. dose, the bioavailability following oral administration for TMP was 98% and 87% for SMX. Intraperitoneal bioavailability was 73% for TMP and 65% for SMX after a 4-h dwell.

After 24 h, regardless of the route of administration, less than 3% of TMP and less than 6% of SMX appeared in dialysate.

We conclude that peritoneal losses contribute insignificantly to TMPISMX elimination during CAPO.

Peritonitis in Continuous Ambulatory Peritoneal Dialysis (CAPD) Patients: A Randomized Clinical Trial of Cotrimoxazole Prophylaxis

A double-blind randomized controlled trial compared the effectiveness of prophylactic oral trimethoprim/sulfamethoxazole (cotrimoxazole) to a placebo in preventing peritonitis in continuous ambulatory peritoneal dialysis (CAPD) patients. A daily trimethoprim/sulfamethoxazole dose of 160/800 mg gives a steady state dialysate concentration of 1.07/4.35 mg/L in the final dwell of each dosing interval. Identification of a 40% reduction in peritonitis probability with 80% statistical power and a type 1 error probability of 0.05 required 52 subjects per group. With stratification by previous peritonitis, 56 were allocated to cotrimoxazole and 49 to placebo. For cotrimoxazole there were five deaths and seven catheter losses. For placebo there were three deaths and nine catheter losses. There were 20 withdrawals from cotrimoxazole and 9 from the placebo group. With respect to time to peritonitis, there was no statistically significant difference between cotrimoxazole and placebo groups (p = 0.19). At 6 months, 64.1% of cotrimoxazole and 62.5% of placebo were peritonitis free; at 12 months 41.9% of cotrimoxazole and 35% of placebo were peritonitis free. There was no effect (p > 0.05) of age, sex, catheter care technique, spike or luer, or dialysate additives. Previous peritonitis increased the risk of peritonitis by 2.06 (95% CI, 3.61–1.18) while frequent (six weekly) extension tubing changes increased the risk of by 1.79, (95% CI, 3.04–1.02) when compared to six monthly changes. Cotrimoxazole appears ineffective in prevention of CAPD peritonitis.

De novo WNT5A-associated autosomal dominant Robinow syndrome suggests specificity of genotype and phenotype

Robinow Syndrome (RS), a rare skeletal dysplasia syndrome, is characterized by dysmorphic features resembling a fetal face, mesomelic limb shortening, hypoplastic external genitalia in males, and renal and vertebral anomalies. Both autosomal dominant and autosomal recessive patterns of inheritance have been reported. Since the description of autosomal dominant Robinow Syndrome (ADRS; OMIM 180700) in 1969 by Meinhard Robinow and colleagues, the molecular etiology remained elusive until only recently. WNT5A was proposed to be the candidate gene for ADRS, as mutations were found in two affected families, one of those being the originally described index family. We report three families with RS caused by novel heterozygous WNT5A mutations, which were confirmed in the first family by whole exome sequencing, and in all by Sanger sequencing. To our knowledge, this is the largest number of published families with ADRS in whom a WNT5A mutation was identified. Families 1 and 2 are the first cases showing de novo inheritance in the affected family members and thus strengthen the evidence for WNT5A as the causative gene in ADRS. Finally, we propose WNT5A mutation specificity in ADRS, which may affect interactions with other proteins in the Wnt pathway.

Management considerations to implementing pharmaceutical care

Progressing towards the goal of PC requires a fundamental change to pharmacy practice. Strong leadership and management skills will be needed to facilitate this change. Even with enthusiastic and capable staff, implementation of the PC model will require considerable effort. Changes to the department's mission statement and organizational structure will be required. From this beginning, an action plan for the department can be developed. This plan includes the training of individuals and/or recruiting the necessary personnel. An ongoing education program, as well as determining the value of your service, is required. With successful implementation the PC model will lead to the acceptance of the pharmacist's role as the person responsible for identifying, preventing, and resolving drug-related problems.

Childhood deaths from toy balloons

We describe four children who died of suffocation by rubber balloons in Canada between 1983 and 1988. In the United States, at least 121 children have died in a similar manner in the 15 years between 1973 and 1988 according to a report by the US Consumer Product Safety Commission. Although the highest mortality occurred among infants, 30 (25%) of the 121 deaths occurred in children 6 years of age or older. Balloons account for 43% of the approximately 15 childhood deaths related to children's products that are documented each year by the Consumer Product Safety Commission. Toy rubber balloons are thus the leading cause of pediatric choking deaths from children's products. Preventive efforts should be directed toward a ban on this type of balloon and the development of safer alternatives. Meanwhile, public information campaigns should alert parents, physicians, and policymakers to the dangers of toy rubber balloons.