Treatment of childhood bacterial meningitis

Outbreak History, Biofilm Formation, and Preventive Measures for Control of Cronobacter sakazakii in Infant Formula and Infant Care Settings

Previously known as Enterobacter sakazakii from 1980 to 2007, Cronobacter sakazakii is an opportunistic bacterium that survives and persists in dry and low-moisture environments, such as powdered infant formula. Although C. sakazakii causes disease in all age groups, infections caused by this pathogen are particularly fatal in infants born premature and those younger than two months. The pathogen has been isolated from various environments such as powdered infant formula manufacturing facilities, healthcare settings, and domestic environments, increasing the chance of infection through cross-contamination. The current study discusses the outbreak history of C. sakazakii and the ability of the microorganism to produce biofilms on biotic and abiotic surfaces. The study further discusses the fate of the pathogen in low-moisture environments, articulates preventive measures for healthcare providers and nursing parents, and delineates interventions that could be utilized in infant formula manufacturing to minimize the risk of contamination with Cronobacter sakazakii.

Invasive Enterobacter sakazakii disease in infants

Enterobacter sakazakii kills 40%–80% of infected infants and has been associated with powdered formula. We analyzed 46 cases of invasive infant E. sakazakii infection to define risk factors and guide prevention and treatment. Twelve infants had bacteremia, 33 had meningitis, and 1 had a urinary tract infection. Compared with infants with isolated bacteremia, infants with meningitis had greater birthweight (2,454 g vs. 850 g, p = 0.002) and gestational age (37 weeks vs. 27.8 weeks, p = 0.02), and infection developed at a younger age (6 days vs. 35 days, p<0.001). Among meningitis patients, 11 (33%) had seizures, 7 (21%) had brain abscess, and 14 (42%) died. Twenty-four (92%) of 26 infants with feeding patterns specified were fed powdered formula. Formula samples associated with 15 (68%) of 22 cases yielded E. sakazakii; in 13 cases, clinical and formula strains were indistinguishable. Further clarification of clinical risk factors and improved powdered formula safety is needed.

Enterobacter sakazakii: a coliform of increased concern to infant health

The first cases of neonatal meningitis believed to have been caused by Enterobacter sakazakii were reported in 1961. Prompted by several subsequent outbreaks of E. sakazakii infections in neonates and an increasing number of neonates in intensive care units being fed rehydrated powdered infant formula, considered to be a source of the pathogen, public health authorities and researchers are exploring ways to eliminate the bacterium or control its growth in dry infant formula, processing environments and formula preparation areas in hospitals. Reviewed here are advances in taxonomy and classification of E. sakazakii, methods of detecting, isolating and typing the bacterium, antibiotic resistance, clinical etiology and pathogenicity. Outbreaks of E. sakazakii infections in neonates and adults are summarized. Reports on the presence of E. sakazakii in clinical settings, the environment and foods and food processing facilities are reviewed. Tolerance of the pathogen to environmental stresses, its behavior in powdered and rehydrated infant formulae and hazard analysis and risk management are discussed. Research needs are presented.

Treatment of Salmonella meningitis: two case reports and a review of the literature

BACKGROUND

Salmonella species now represent a leading cause of Gram-negative bacterial meningitis in the developing world. Various drugs have been used for the treatment of Salmonella meningitis over the past decades, but mortality, neurologic sequelae and relapse rates remain high. In this report we describe two children aged 8 and 9 months who presented within a week to our hospital with Salmonella meningitis. They were treated with penicillin and chloramphenicol but progressed rapidly to death within 48 h.

AIM

The aim of this article is to review all published English literature on the treatment of Salmonella meningitis and identify the best drug option for its treatment. This was done by comparing the outcomes such as cure, failure, relapse, and death rates.

METHOD

A Medline electronic search was carried out to find and retrieve articles that have been published since 1987, when the last review of Salmonella meningitis was done.

RESULTS

Salmonella typhimurium was the commonest organism reported, and 89.7% of infections occurred in children less than 1 year old. Fluoroquinolones had a cure rate of 88.9%, while the third-generation cephalosporins had a cure rate of 84.6%. Conventional antibiotics (chloramphenicol, ampicillin, and cotrimoxazole) had a cure rate of 41.2%, a relapse rate of 11.8%, and an associated mortality of 44.7%. Treatment with fluoroquinolone and imipenem resulted in no deaths. There were, however, only two cases that were treated with imipenem.

CONCLUSION

When Salmonella meningitis is suspected, third-generation cephalosporins, with or without a fluoroquinolone, may be the best option for treatment.

Enterobacter sakazakii infections among neonates, infants, children, and adults. Case reports and a review of the literature

Enterobacter sakazakii can cause serious infections especially among the very young and the elderly. It continues to be more common among neonates and infants than adults. Its tropism for the central nervous system in neonates and infants remains a mystery. Among neonates and infants, E. sakazakii has a propensity to cause meningitis resulting in ventriculitis, brain abscess or cyst formation, and development of hydrocephalus requiring ventricular-peritoneal shunt. Computed tomography of the head is therefore useful in following patients with E. sakazakii meningitis. Mortality and morbidity of E. sakazakii meningitis is high, and virtually all patients recovering from the central nervous system infection suffered mental and physical developmental delays. The case-fatality rate decreased among patients with meningitis treated with the third-generation cephalosporins. Most adults with E. sakazakii infection had serious underlying diseases and 50% of the adults with the infection had malignancies. However there has never been a known case of meningitis. Increasing antibiotic resistance among Enterobacter species should lead one to consider using the carbapenems or the newer cephalosporins in combination with a second agent such as an aminoglycoside. Limited data suggest that trimethoprim-sulfamethoxazole may be a useful agent in the treatment of infections caused by the Enterobacter species, especially in view of the production of extended-spectrum beta-lactamases capable of inactivating the cephalosporins and extended-spectrum penicillin.

Neonatal Salmonella meningitis: two case reports

Two cases of neonatal Salmonella meningitis are reported. Both infants were seriously ill: one died 6 days after admittance to the hospital; the other required artificial ventilation for 4 days and recovered without sequelae. In both cases close relatives had shown signs of gastrointestinal infection just prior to the reported cases. The symptoms, the outcome and antibiotic treatment are discussed. In view of the increasing incidence of salmonella infections in Denmark and the serious prognosis of neonatal meningitis, it is important to consider the diagnosis in all cases of bacterial meningitis in infancy.

Salmonella typhi meningitis

Whereas typhoid fever is still an endemic disease in some parts of the world, meningeal involvement in this disease is a rare occurrence. We report a case of Salmonella typhi meningitis in a 70-year-old woman. The patient was treated with ampicillin and the only sequela was right-sided deafness.

Cefotaxime dosage in infants and children. Pharmacokinetic and clinical rationale for an extended dosage interval

Cefotaxime is a third generation cephalosporin antimicrobial agent which has received wide acceptance as a first-line antibiotic for many infections in neonates, infants and children. With an average elimination half-life of about 1 h, cefotaxime is not considered to be a 'long half-life cephalosporin' like ceftriaxone. For this reason, currently accepted dosage regimens for cefotaxime in infants and children employ a dosage of 50 mg/kg every 6 h. Re-examination of the paediatric pharmacokinetic data for cefotaxime and use of simple multiple-dose pharmacokinetic simulation of alternative dosage regimens was performed. From this analysis, regimens administering 75 mg/kg of the drug every 8 h or every 12 h were projected to produce serum cefotaxime concentrations adequate to effectively kill many of the common pathogens against which the drug is currently indicated for use in children. The clinical utility of these alternative dosage regimens was supported by a review of the medical literature and examination of the clinical results from studies in neonates, infants and children where cefotaxime was administered in 2 to 3 divided doses daily. It would appear, therefore, that increasing the cefotaxime dosage to 75 mg/kg administered at 8 h intervals would result in less frequent drug administration which would not be expected to compromise safety and efficacy. Alternative dosage regimens for cefotaxime merit further consideration and clinical evaluation before they become commonly used in paediatric therapeutics.