Prophylaxis, cost and effectiveness of therapy of infections caused by gram-positive organisms in neutropenic children

Safety of fluconazole in paediatrics: a systematic review

PURPOSE

To determine the safety of fluconazole in neonates and other paediatric age groups by identifying adverse events (AEs) and drug interactions associated with treatment.

METHODS

A search of EMBASE (1950-January 2012), MEDLINE (1946-January 2012), the Cochrane database for systematic reviews and the Cumulative Index to Nursing and Allied Health Literature (1982-2012) for any clinical study about fluconazole use that involved at least one paediatric patient (≤17 years) was performed. Only articles with sufficient quality of safety reporting after patients' exposure to fluconazole were included.

RESULTS

We identified 90 articles, reporting on 4,209 patients, which met our inclusion criteria. In total, 794 AEs from 35 studies were recorded, with hepatotoxicity accounting for 378 (47.6 %) of all AEs. When fluconazole was compared with placebo and other antifungals, the relative risk (RR) of hepatotoxicity was not statistically different [RR 1.36, 95 % confidence interval (CI) 0.87-2.14, P = 0.175 and RR 1.43, 95 % CI 0.67-3.03, P = 0.352, respectively]. Complete resolution of hepatoxicity was achieved by 84 % of patients with follow-up available. There was no statistical difference in the risk of gastrointestinal events of fluconazole compared with placebo and other antifungals (RR 0.81, 95 % CI 0.12-5.60, P = 0.831 and RR 1.23, 95 %CI 0.87-1.71, P = 0.235, respectively). There were 41 drug withdrawals, 17 (42 %) of which were due to elevated liver enzymes. Five reports of drug interactions occurred in children.

CONCLUSION

Fluconazole is relatively safe for paediatric patients. Hepatotoxicity and gastrointestinal toxicity are the most common adverse events. It is important to be aware that drug interactions with fluconazole can result in significant toxicity.

Antibiotic prophylaxis for bacterial infections in afebrile neutropenic patients following chemotherapy

BACKGROUND

Bacterial infections are a major cause of morbidity and mortality in patients who are neutropenic following chemotherapy for malignancy. Trials have shown the efficacy of antibiotic prophylaxis in reducing the incidence of bacterial infections but not in reducing mortality rates. Our systematic review from 2006 also showed a reduction in mortality.

OBJECTIVES

This updated review aimed to evaluate whether there is still a benefit of reduction in mortality when compared to placebo or no intervention.

SEARCH METHODS

We searched the Cochrane Cancer Network Register of Trials (2011), Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library Issue 2, 2011), MEDLINE (1966 to March 2011), EMBASE (1980 to March 2011), abstracts of conference proceedings and the references of identified studies.

SELECTION CRITERIA

Randomised controlled trials (RCTs) or quasi-RCTs comparing different types of antibiotic prophylaxis with placebo or no intervention, or another antibiotic, to prevent bacterial infections in afebrile neutropenic patients.

DATA COLLECTION AND ANALYSIS

Two authors independently appraised the quality of each trial and extracted data from the included trials. Analyses were performed using RevMan 5.1 software.

MAIN RESULTS

One-hundred and nine trials (involving 13,579 patients) that were conducted between the years 1973 to 2010 met the inclusion criteria. When compared with placebo or no intervention, antibiotic prophylaxis significantly reduced the risk of death from all causes (46 trials, 5635 participants; risk ratio (RR) 0.66, 95% CI 0.55 to 0.79) and the risk of infection-related death (43 trials, 5777 participants; RR 0.61, 95% CI 0.48 to 0.77). The estimated number needed to treat (NNT) to prevent one death was 34 (all-cause mortality) and 48 (infection-related mortality).Prophylaxis also significantly reduced the occurrence of fever (54 trials, 6658 participants; RR 0.80, 95% CI 0.74 to 0.87), clinically documented infection (48 trials, 5758 participants; RR 0.65, 95% CI 0.56 to 0.76), microbiologically documented infection (53 trials, 6383 participants; RR 0.51, 95% CI 0.42 to 0.62) and other indicators of infection.There were no significant differences between quinolone prophylaxis and TMP-SMZ prophylaxis with regard to death from all causes or infection, however, quinolone prophylaxis was associated with fewer side effects leading to discontinuation (seven trials, 850 participants; RR 0.37, 95% CI 0.16 to 0.87) and less resistance to the drugs thereafter (six trials, 366 participants; RR 0.45, 95% CI 0.27 to 0.74).

AUTHORS' CONCLUSIONS

Antibiotic prophylaxis in afebrile neutropenic patients significantly reduced all-cause mortality. In our review, the most significant reduction in mortality was observed in trials assessing prophylaxis with quinolones. The benefits of antibiotic prophylaxis outweighed the harm such as adverse effects and the development of resistance since all-cause mortality was reduced. As most trials in our review were of patients with haematologic cancer, we strongly recommend antibiotic prophylaxis for these patients, preferably with a quinolone. Prophylaxis may also be considered for patients with solid tumours or lymphoma.

Antibiotic prophylaxis for bacterial infections in afebrile neutropenic patients following chemotherapy

BACKGROUND

Bacterial infections are a major cause of morbidity and mortality in neutropenic patients following chemotherapy for malignancy. Trials have shown the efficacy of antibiotic prophylaxis in decreasing the incidence of bacterial infections, but not in reducing mortality rates.

OBJECTIVES

This review aimed to evaluate whether antibiotic prophylaxis in afebrile neutropenic patients reduced mortality when compared to placebo or no intervention.

SEARCH STRATEGY

Electronic searches on The Cochrane Cancer Network Register of Trials (2004), Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library Issue 4, 2004), MEDLINE (1966 to 2004) and EMBASE (1980 to 2004) and abstracts of conference proceedings; references of identified studies; the first author of each included trial was contacted.

SELECTION CRITERIA

RCTs or quasi-RCTs comparing different types of antibiotic prophylaxis with placebo or no intervention, or another antibiotic to prevent bacterial infections in afebrile neutropenic patients.

DATA COLLECTION AND ANALYSIS

Two authors independently appraised the quality of each trial and extracted data from the included trials. Relative risks (RR) or average differences, with their 95% confidence intervals (CI) were estimated.

MAIN RESULTS

One hundred trials (10,274 patients) performed between the years 1973 to 2004 met inclusion criteria. Antibiotic prophylaxis significantly decreased the risk for death when compared with placebo or no intervention (RR, 0.66 [95% CI 0.54 to 0.81]). The authors estimated the number needed to treat (NNT) in order to prevent 1 death from all causes as 60 (95% CI 34 to 268). Prophylaxis resulted in a significant decrease in the risk of infection-related death, RR 0.58 (95% CI 0.45 to 0.74) and in the occurrence of fever, RR 0.78 (95% CI 0.75 to 0.82). A reduction in mortality was also evident when the more recently conducted quinolone trials were analysed separately. Quinolone prophylaxis reduced the risk for all-cause mortality, RR 0.52 (95% CI, 0.37 to 0.84).

AUTHORS' CONCLUSIONS

Our review demonstrated that prophylaxis significantly reduced all-cause mortality. The most significant reduction in mortality was observed in trials assessing prophylaxis with quinolones. The benefit demonstrated in our review outweighs harm, such as adverse effects, and development of resistance, since all-cause mortality is reduced. Since most trials in our review were of patients with haematologic cancer, prophylaxis, preferably with a quinolone, should be considered for these patients.

A survey of the use of teicoplanin in patients with haematological malignancies and solid tumours

A significant number of open and comparative studies have now addressed the use of teicoplanin in the treatment of documented or presumed infection in patients with haematological and non-haematological malignancy. Available evidence suggests that teicoplanin is an effective agent against such infections, with an excellent safety profile. The use of teicoplanin and vancomycin may be justified as part of the initial management of clinically infected right atrial catheters in patients with malignancy. The first-line use of glycopeptides may also be appropriate in units where streptococcal and methicillin resistant staphylococcal infections are prevalent. However, such a policy should be reviewed regularly. Except in the above situations, a delay in the introduction of either teicoplanin or vancomycin in cancer patients does not appear to produce any excess mortality, but there may be some additional morbidity in terms of fever and malaise. The introduction of glycopeptides as second-line agents is indicated for sensitive, microbiologically documented infections and for patients who have not responded to empirical, first-line therapy. Non-inpatient treatment with teicoplanin is an area of ongoing interest and may be justified on both humanitarian and pharmacoeconomic grounds. The use of glycopeptides in the prophylactic setting remains controversial and should be avoided while the emergence of resistance, particularly in enterococci, should be monitored closely.

Detection of bacteraemia in patients with fever and neutropenia using 16S rRNA gene amplification by polymerase chain reaction

Episodes of fever and neutropenia are common complications of treatment for cancer. The use of prophylactic and early empirical antibiotics has reduced mortality but decreases the sensitivity of diagnostic tests based on culture. The aim of this study was to determine the potential of a broad diagnostic approach (eubacterial) based on 16S rRNA gene amplification and sequencing to augment cultural methods of diagnosis of bacteraemia in patients with fever and neutropenia in a regional paediatric oncology centre. One hundred eleven patient-episodes of fever and neutropenia were evaluated during the study period, 17 of which were associated with positive blood cultures, as follows: Staphylococcus epidermidis (n = 6 episodes), Enterococcus faecium (n = 2), Streptococcus sanguis (n = 3), Streptococcus mitis (n = 3), Staphylococcus aureus (n = 1), Micrococcus spp. (n = 1), and Stenotrophomonas maltophilia (n = 1). Eubacterial polymerase chain reaction (PCR) detected bacterial DNA in nine of 11 blood culture-positive episodes for which a sample was available for PCR; the species identified by sequence analysis were identical to those derived from the conventional identification of the cultured isolates. Bacterial DNA was detected in 20 episodes (21 bacterial sequences) associated with negative blood cultures, 18 of which occurred in patients who were receiving antibiotics at the time of sample collection. The species presumptively identified by partial 16S rRNA gene sequencing were as follows: Pseudomonas spp. (n = 6 episodes), Acinetobacter spp. (n =5 ); Escherichia spp. (n = 3); Moraxella spp. (n = 3); Staphylococcus spp. (n = 2); Neisseria spp. (n = 1); and Bacillus spp. (n = 1). The results of this study suggest that molecular techniques can augment cultural methods in the diagnosis of bacteraemia in patients who have been treated with antibiotics.

Infection risk factors in febrile, neutropenic children and adolescents

We studied 276 fever episodes with an absolute neutrophil count (ANC) < 500/mm3 to determine patient characteristics predicting serious infection. Infections occurred in 38% of patients. Blood cultures were positive in 58% of documented infections. There was no difference in the rates of infection or positive blood culture when ANC was < 200/mm3 compared with a higher ANC. However, certain high risk infections were more common with an ANC < 200/ mm3. Leukemia patients had more infections compared with other groups. Serious infections were more common during induction therapy or relapse. Infection incidence varied significantly with patient age and onset of fever in the inpatients. Less than one fifth of febrile neutropenic episodes had no risk features for serious infection. We conclude that several clinical characteristics correlate with serious infection in febrile, neutropenic children and adolescents receiving modern supportive care. Despite improvements in supportive care measures, most febrile, neutropenic patients need close observation and empiric intravenous antibiotic therapy.

Prevention of catheter-related infections by silver coated central venous catheters in oncological patients

Catheter-related infection (CRI) is a serious complication of central venous catheterization. We have investigated the efficacy of a silver-coated polyurethane catheter (Pellethane, Fresenius AG, Germany) in preventing CRI in oncological patients receiving chemotherapy in a phase II study. From November 1992 through April 1994, 266 patients were assigned to receive single lumen catheters, either standard uncoated catheters (UC, n = 113) or silver-coated ones (SC, n = 120). Catheters were inserted into the internal jugular vein after institutional approval and informed consent. Duration of catheterization (UC vs. SC = 13.3 vs. 12.7 days) and leukopenia (< 1.0 x 10(9) WBC/l; 4.3 vs. 3.6 days) were similar in both groups demonstrating a comparable risk for infections. Skin reactions at the catheter entry site were recorded daily. CRI and colonization rates were studied by semiquantitatively culturing intradermal and intravascular segments. CRI were confirmed by blood cultures obtained via catheter and from peripheral veins in cases of suspected sepsis or at the end of catheterization. No adverse effects from the silver-coated catheter could be observed. The bacteriological results showed that SC were colonized (> 15 CFU) in 45.1% and UC in 44.2%. CRI developed in 21.2% of the UC patients but only in 10.2% of the SC patients (p = 0.011). We conclude that this new silver-coated central venous catheter is biocompatible and effective in reducing the incidence of catheter-related infections in oncological patients.

Teicoplanin or vancomycin in the treatment of gram-positive infections?

The glycopeptide antibiotics vancomycin and teicoplanin have similar mechanisms of action on bacterial cell wall synthesis. Their spectra of activity are limited to Gram-positive bacteria, with the degree of bactericidal activity depending on the species of micro-organism. Staphylococcus aureus, Staphylococcus epidermis, enterococci and Clostridium difficile are generally sensitive, including methicillin-resistant strains of S. aureus and S. epidermidis. Glycopeptide resistance has recently emerged in staphylococci and enterococci. Vancomycin has a shorter half-life than teicoplanin and requires multiple dosing to maintain adequate serum levels. It can only be given by prolonged intravenous infusion over 1 h. In contrast, the pharmacokinetics of teicoplanin allow for once-daily dosing, either by rapid intravenous infusion or by the intramuscular route. The latter offers reliable absorption for patients with limited venous access and is also of benefit for out-patient therapy. Teicoplanin is a safer drug than vancomycin. It is associated with a lower incidence of nephrotoxicity or ototoxicity. Compared to vancomycin, the availability of the intramuscular route and the absence of a requirement for routine serum monitoring, together with the reduced need to treat drug-related side-effects make teicoplanin more cost-effective. It is as effective as vancomycin for most indications, is safe, easy to administer and an important agent for treating Gram-positive infections. Its role in hospitals is likely to increase if the price of drug acquisition is kept low.

In vitro activity of vancomycin and teicoplanin against Staphylococcus aureus and Staphylococcus epidermidis colonizing catheters

In a quantitative in vitro model the activity of vancomycin and teicoplanin in two concentrations (4 x MBC and 1 mg/l) against Staphylococcus aureus and a slime-producing Staphylococcus epidermidis strain colonizing the internal surface of polyurethane and silicone catheters was studied. In comparison with vancomycin, teicoplanin achieved a significantly greater reduction (p < 0.05) in the counts of Staphylococcus aureus and Staphylococcus epidermidis adhering to both polyurethane and silicone catheters.