Assessment of the in vivo formation of biofilm on external ventricular drainages.

Biofilm formation on external ventricular drainages (EVDs) has been postulated as the main pathogenic mechanism for EVD-associated ventriculitis. However, biofilm on EVDs has never been systematically studied and the in vivo effect of antibiotic-impregnated EVDs on biofilm has not been assessed. The aim of this study was to measure the prevalence of biofilm formation on EVDs and to analyze the influence of antibiotic-impregnated EVD on the risk of biofilm formation and ventriculitis. Consecutive patients with EVDs were included in the study. Surveillance cerebrospinal fluid (CSF) cultures were performed twice a week. Withdrawn EVDs were cultured using standard bacteriologic techniques and examined under a scanning electron microscope. We collected 32 EVDs, 18 of which (56 %) were antibiotic-impregnated EVDs. Biofilm was present on 24 EVDs (75 %), ventriculitis was diagnosed in 6 patients (19 %), and colonization occurred in 12 patients (38 %). All cases of ventriculitis were due to Gram-negative bacteria. Biofilm was more frequent on EVDs originating from patients with ventriculitis or bacterial colonization. Impregnated EVDs did not avoid ventriculitis or colonization, but biofilm development on these devices depended on the time from insertion and varied from 67 % for those used for <7 days to 88 % for those used for ≥ 7 days (p = 0.094). In conclusion, biofilm is a common phenomenon on EVDs. Currently available impregnated EVDs could not avoid ventriculitis due to multidrug-resistant Gram-negative bacteria, but a trend of delayment of biofilm development was observed.

Initial proximal obstruction of ventriculoperitoneal shunt in patients with preterm-related posthaemorrhagic hydrocephalus.

BACKGROUND/AIMS: Obstruction is the most common complication of ventriculoperitoneal shunts in patients with hydrocephalus. Despite technical advances, rates of obstruction have barely decreased and remain at over 40% of cases. Patients suffering from preterm-related posthaemorrhagic hydrocephalus are considered a group with a particularly high risk of obstruction. The aim of the present study was to review our series of patients with preterm-related posthaemorrhagic hydrocephalus and analyse the occurrence of the first ventricular shunt obstruction as well as the related clinical and radiological factors. METHODS: We conducted a retrospective review of 103 cases treated from 1982 to 2010. Descriptive analysis, raw and adjusted bivariate correlations and survival analysis were performed. RESULTS: Over the course of the follow-up, 42 patients presented at least one episode of obstruction that required proximal revision. Medium-opening pressure valves were associated with a higher rate of obstruction compared to low-opening pressure valves; however, in our series this association became statistically significant only in patients with a weight of over 2,000 g at the time of surgery (odds ratio 6.75). The occurrence of previous infection and the development of late slit ventricle syndrome were also significantly associated with obstruction of the ventricular catheter (odds ratios 3.35 and 4.27, respectively). CONCLUSIONS: Rates of shunt obstruction in preterm-related posthaemorrhagic hydrocephalus remain high but do not seem to be higher than in other groups of paediatric hydrocephalus. Prevention of infection and the use of the appropriate type of valve design can help to decrease the incidence of proximal shunt obstruction, which in turn could decrease the incidence of symptomatic slit ventricle syndromes.

Ventriculitis por Listeria monocytogenes / Ventriculitis secondary to Listeria monocytogenes

No disponible

Surgical removal after first bleeding of an arteriovenous malformation previously obliterated with radiosurgery: case report.

BACKGROUND: Radiosurgery has been widely used to treat cerebral AVMs, providing angiographic evidence of obliteration of the malformation in 80% to 95% of patients, after a latency period of 2 to 5 years. CASE DESCRIPTION: We describe a case of hemorrhage, 6 years after radiosurgery and 4 years after complete angiographic obliteration of an AVM that had not previously bled and that persisted angiographically, obliterated after bleeding. RESULTS: Several treatment options have been reported for patients with completely obliterated AVMs that bled, including conservative treatment, repeated radiosurgery, and open surgery with resection of AVM remnants. In the present case, the decision to perform surgery based on the probable association of the enhancing area observed on the MRI and the histologic findings was finally confirmed. CONCLUSIONS: Magnetic resonance imaging enhancement areas on the obliterated AVMs may have a histopathologic correlation with persistence of permeable vessels and can be used as a guide for surgery and postoperative control. The follow-up of angiographically obliterated AVMs that bleed remains a matter of discussion twofold: regarding timing and use of a proper diagnostic test.

Silicon, phosphorus, sulphur, chlorine and ash contents of Spanish commercial honeys.

Silicon, phosphorus, sulphur, chlorine and ash contents were determined in samples of 24 Spanish commercial honeys. Mean contents (mg/kg of honey) were 3.2 for silicon, 78 for phosphorus, 45 for sulphur and 262 for chlorine. The values for phosphorus and chlorine are high with respect to honeys from other regions. Mean ash content was 0.19%. In all cases there were high coefficients of variation, ranging from 0.43 for silicon to 0.58 for phosphorus.