Prenatal diagnosis of the isodicentric chromosome 22 associated with cat eye syndrome by multiplex ligation-dependent probe amplification

Cat eye syndrome (CES) is a very rare chromosomal syndrome characterized by various malformations such as anal atresia, preauricular malformation, coloboma of the iris, and congenial heart and renal defects. This genetic disorder is caused by partial duplication of chromosome 22, mostly as a result of a supernumerary isodicentric marker chromosome idic(22)(q11.2). Various congenital abnormalities and extreme phenotypic variability in CES patients have been reported, which have made prenatal diagnosis of CES difficult. We report the first case diagnosed with CES prenatally by multiplex ligation-dependent probe amplification in a woman who was referred to our hospital, for a fetus presenting with heart anomaly.

Pseudoisodicentric X chromosome in a female with primary amenorrhea

A 24-year-old female with primary amenorrhea was referred for a chromosome study. The karyotype of the patient was 46,X,der(X) under initial GTG-banding analysis. Fluorescence in situ hybridization (FISH) analysis with an LSI Kallmann (KAL) region probe [probes for Xp22.3(KAL) and CEP(X) for control] was carried out. The abnormal chromosome was KAL- and CEP(X)x2. In addition, interphase FISH analysis revealed the patient to be mosaic for two different cell lines: 90% of cells had three signals and 10% of the cells had only one signal for CEP(X). Based on these results, the karyotype of the patient was 45,X/46,X,psu idic(X)(p22.1), which is partial trisomy for Xqter-->Xp22.1 and partial monosomy for Xpter-->Xp22.1. This karyotype was considered a variant of Turner syndrome. In summary, Idic(X) and low-level mosaicism was successfully characterized by FISH analysis with a CEP(X) probe.

Therapeutic Drug Monitoring of Vancomycin / 감염

BACKGROUND: Vancomycin assay was performed to evaluate the clinical significance of therapeutic drug monitoring (TDM) of vancomycin and to compare pharmacokinetic parameters of vancomycin in our patients with population pharmacokinetic parameters. METHODS: In seventy-eight patients (45 males, 33 females), vancomycin serum concentrations were measured by fluorescence polarization immunoassay. At steady-state, peak levels were obtained one hour postinfusion, and trough levels were obtained just before a next dose. And also predicted serum vancomycin levels were determined by CAPCIL program in all subjects and compared with measured values, respectively. All patients were divided into two groups. Sixty-two patients in group I had a creatinine concentration in serum of 1.2 mg/dL. Follow-up second vancomycin concentrations were measured in 22 of 78 patients several days after initial TDM and were compared with initial TDM results. RESULTS: Mean values of peak and trough vancomycin concentration were 30.1 and 10.4, and 37.3 and 14.5 microgram/mL in groups I, and II, respectively. Predicted mean values of those were 26.3 and 9.2, and 28.2 and 7.8 microgram/mL in groups I, and II, respectively. Statistically significant differences between predicted and measured values in peak levels of group I,and IIand in trough level of group IIwere observed (P<0.01). Dose modification were required in 13 (21%) of 62 patients with normal renal function, and in 9 (56%) of 16 patients with abnormal renal function. Among 79 paired samples with a trough value below 15 mg/L, there were no peaks greater than 40 mg/L except two samples. CONCLUSION: Significant differences were noted between predicted and measured serum vancomycin concentrations and so TDM of vancomycin is needed to obtain effective dose and interval of vancomycin. More data about measured peak and trough values should be collected to establish pharmacokinetic parameters of vancomycin in Korean population.