Antimicrobial therapy and local toxicity of intraventricular administration of vancomycin in a neonate with ventriculitis

Infection is the most common complication and cause of failure of cerebrospinal fluid (CSF) shunt devices used to control hydrocephalus. A male newborn was admitted for treatment of congenital occlusive hydrocephalus by means of a ventriculo-peritoneal shunt. A day later, the skin area around the site of insertion of ventriculo-peritoneal catheter was red and edematous. Intravenous ceftazidime and vancomycin were initiated. The shunt was removed but the external ventricular drain was preserved. Blood and CSF cultures showed Enterococcus faecalis sensitive to vancomycin, ciprofloxacin and gentamicin, but resistant to ampicillin. Intraventricular administration of vancomycin 10 mg/24 h was initiated through the external ventricular drain. Before the first dose of vancomycin intraventricularly, CSF levels were 19 mg/dL as a result of administration. On the third day of intraventricular dosing, vancomycin levels in CSF reached 388 mg/dL and protein levels were 1160 mg/dL. On the fifth day of intraventricular treatment the patient had clinically improved and was bacteriologically cured. However, in CSF, protein levels were 3300 mg/dL and vancomycin levels 201 mg/dL. In an attempt to prevent high and potentially toxic levels in CSF, the intraventricular dose of vancomycin should be individualized according to clinical response, bacteriological cultures, vancomycin levels in CSF, and surrogate markers of neurotoxicity, that is, eosinophilia and high protein levels in CSF.

Experience of a Successful Pediatric Liver Transplant Program in Mexico

Orthotopic liver transplantation (OLT) has been very difficult to develop in Mexico and for many years its occurrence was anecdotal. This report presents the results of a pediatric liver transplant program, analyzing the variables that affect outcomes. Between June 1998 and March 2004, 35 OLT were performed in 34 recipients including 80% cadaveric whole-organ grafts and 20% segmental grafts, with 11% from cadaveric and 9% from living donors. Most of the recipients were infants or toddlers weighing less than 15 kg. There was only 1 case of arterial thrombosis (2.8%); the graft was saved with a Kasai procedure. Biliary complications were present in 22% of cases, all resolved with reoperations. Posttransplant cytomegalovirus infection or reactivation (28%), acute rejection (25%), or posttransplant lymphoproliferative disorders (5.7%) were not a cause of graft or patient loss. Overall, 1- and 5-year patient survival rates are 77.1% and 74.2%, respectively; however, when the 1998-2000 cohort was compared with the 2001-2004 cohort, there was a significant difference in survival (P = .004). The 1-year patient survival for the later group is 91.6%. We performed the first successful living donor liver transplantation and the first simultaneous liver-kidney transplantation in a child in our country. Our results demonstrate that pediatric liver transplantation is a feasible undertaking in Mexico, with survival rates comparable to those of foreign centers.

[Exposure to group B Streptococcus among Mexican women in reproductive age]

OBJECTIVE

To assess the prevalence of IgG antibodies against Group B streptococci (GBS) among women of reproductive age in Mexico.

MATERIAL AND METHODS

Serum specimens were drawn from 15 to 40 year-old women, representative of all regions and socioeconomic levels of the country. The sample was randomly selected from Banco Nacional de Sueros (National Sera Bank); serum samples were collected during a national seroepidemiologic survey conducted in 1987-1988. The assays for standardization and for evaluation of seroprevalence were carried out at the Hospital de Pediatría del Centro Médico Nacional Siglo XXI (Children's Hospital) Instituto Mexicano del Seguro Social (IMSS) (Mexican Institute of Social Security) from January to November 1995. IgG antibodies against group B antigen were studied with an enzyme-linked immunosorbent assay (ELISA) developed in our lab. Group B antigen was produced and purified from the reference strain GBS 110.

RESULTS

A total of 2669 serum samples were studied; 2405 were positive to anti-group B antigen IgG antibodies, for a seroprevalence of 90.2%. No differences in prevalence were found among the different age groups or among the different states of the country.

CONCLUSIONS

The high seroprevalence of antibodies against GBS suggests that young women in Mexico are commonly exposed to GBS infection.

Cytomegalovirus infection in patients with solid-organ transplant. Recently reviewed immunologic response and pathogenicity mechanisms

Cytomegalovirus (CMV) infection in immunocompromised host is an important cause of morbidity and mortality. The protective immunity against the virus is both humoral and cellular. Immunologic mechanisms in rejection as in the immune response against CMV infection are similar but there is difficult to separe as histologic and clinically independent events. At least eight different genes of CMV are homologous to human proteins related to the immune response. The potential role of these genes with homology to human genes can be at different levels. The relevance that immunodominant antigens have on the natural control of CMV infection, suggests that the future design of a vaccine directed to protecting from disease those susceptible to primary infection, in an immunocompromised state, should involve a combination of antigens that include pp65, IE1-exon 4 and gB as a recombinant proteins.