Hepatitis C infection in children and adolescents with end-stage renal disease

The prevalence of hepatitis C virus (HCV) infection and the risk factors associated with its transmission are described in a contemporary cohort of 55 children and adolescents with end-stage renal disease (ESRD). Thirty-seven patients were on dialysis or had been transplanted (ESRD) and 18 had chronic renal failure (CRF) but had not yet received dialysis. Seven (19%) tested positive for HCV by enzyme-linked immunosorbent assay (ELISA), polymerase chain reaction (PCR), or both. None of the children with CRF were infected. HCV infection was associated with length of time on dialysis, but not with age, gender, race, or units of blood transfused. These data corroborate earlier reports and confirm that children with ESRD continue to have a high prevalence of HCV. It is also shown for the first time that elevated transaminases should not be employed to predict HCV infection in this cohort, as all affected children had normal serum levels. Because of unique characteristics in this cohort, both ELISA and PCR are required to maximize HCV diagnostic sensitivity. Although HCV remains an important consideration in pediatric ESRD, the present study shows that recent advances in clinical practice have eliminated one of the major ways in which it was previously being transmitted. Received: 30 July 2001 / Revised: 2 January 2002 / Accepted: 4 January 2002     

Protective action of amlodipine on cardiac negative inotropism induced by lipopolysaccharide in rats

Amlodipine has been shown to prevent decrease in vascular responsiveness induced by injection of Salmonella typhosa lipopolysaccharide (LPS); however, there is no study reporting if this protection by amlodipine extends to ventricular contractility. Therefore, we have investigated in rat isolated right ventricle strips contracted by electrical stimulation (1 and 3 Hz and subsequently 1 Hz) whether pre-treatment with amlodipine (15 mg/kg orally for 1 week) precludes the decrease in ventricular contractility related to the induction of nitric oxide synthase stimulated by LPS injection (4 mg/kg intraperitoneally). The induction of septic shock was confirmed in isolated aortic rings from LPS-injected rats by verifying that the contractile response to 1 microM noradrenaline had been (i) decreased after LPS injection and (ii) markedly potentiated by the addition of 10 microM l-arginine. The injection of saline to untreated and amlodipine-treated rats produced a non-significant effect on right ventricular contractility during 180 min. at 3 Hz; the recovery of the contractile response was improved when the stimulation frequency was subsequently returned to 1 Hz after 30 min. In contrast, injection of LPS to untreated and amlodipine-treated rats (amlodipine + LPS) produced a decrease in right ventricular contractility during 180 min. at 3 Hz, an effect that was more pronounced in LPS than in amlodipine-treated rats. These ex vivo results obtained after LPS injection suggest that amlodipine may have inhibited, at least in part, the induction of nitric oxide synthase with a resulting preclusion of the cardiovascular failure produced by septic shock.     

In vitro activities of 10 combinations of antifungal agents against the multiresistant pathogen Scopulariopsis brevicaulis

The activities of 10 combinations of antifungal agents against 25 clinical isolates of Scopulariopsis brevicaulis were tested by the checkerboard technique. An average indifferent effect was detected for all combinations. Synergy was observed for some isolates and combinations, particularly with posaconazole-terbinafine (68% of strains), amphotericin B-caspofungin (60%), and posaconazole-caspofungin (48%).     

Dynamic expression of the membrane attack complex (MAC) of the complement system in failing human myocardium

Inflammatory cytokine-mediated pathways are activated in heart failure and participate in the pathogenesis and progression of the disease. Another major response to inflammation is mediated through the complement system with the production of the membrane attack complex (MAC), a protein known to cause cell lysis and mediate apoptosis. It was postulated that the complement system is activated in patients with heart failure, and this study investigated whether hemodynamic conditions regulate this pathway. The expression of the MAC was assessed in myocardial biopsy samples of normal and failing hearts by immunohistochemistry and Western blot analysis. Myocardial samples from failing hearts were obtained before and after left ventricular assist device implantation. Immunohistochemical staining and Western blot analysis identified increased MAC expression in failing but not normal myocardium. After hemodynamic unloading with left ventricular assist device support, MAC expression returned to levels found in normal controls. In failing hearts, MAC expression did not differ between ischemic and nonischemic causes of heart failure. In conclusion, increased MAC expression in failing human hearts indicates that the complement system is activated in the heart failure milieu. Its removal after hemodynamic normalization is evidence of dynamic regulation, suggesting a pathogenic role for the MAC. These findings identify the complement system as part of a novel pathophysiologic path in heart failure that can potentially be targeted by future therapy.     

Conservative treatment of staphylococcal prosthetic joint infections in elderly patients

Background

We report the outcome of debridement and prosthesis retention plus long-term levofloxacin/rifampicin treatment of prosthetic joint infections.

Methods

Staphylococcal prosthesis joint infections were defined by positive culture of joint aspirate, intraoperative debridement specimens, or sinus tract discharge in the presence of clinical criteria. Patients received long-term oral levofloxacin 500 mg and rifampicin 600 mg once per day. Sixty patients (age 74.6 ± 8.4 years) were included.

Results

Coagulase-negative staphylococci were significantly more frequently isolated in the knee (78.6%; P = .00001). Of the Staphylococcus aureus isolates, 33.3% were methicillin-resistant. Time from arthroplasty to symptoms onset was higher (P = .03) in coagulase-negative staphylococci infections. Global failure was 35% (higher for the knee) and ranged from 16.6% to 69.2% (P = .0045) in patients with symptoms duration of less than 1 month to more than 6 months. A shorter duration of symptoms (P = .001) and time to diagnosis (P = .01) were found in cured patients versus patients showing failure. Among those with S. aureus infections, a higher failure rate was found with methicillin-resistance.

Conclusions

Efficacy was higher in patients with shorter duration of symptoms, earlier diagnosis, hip infections, and methicillin susceptibility.