Asher Barzilai

Quantitative blood cultures in the evaluation of septicemia in children with Broviac catheters

We applied quantitative methods of analysis to all blood cultures drawn during the course of treatment in 28 children with Broviac catheters in a central vein. Thirty febrile episodes in 14 of these patients were evaluated. Samples of blood obtained from a peripheral vein and through the central catheter were cultured quantitatively on agar plates and nonquantitatively in standard broth media. Catheters were judged to be a source of septicemia nine times in seven children. In all nine positive catheter samples, the concentration of pathogens was 10 times as great as that observed in the peripheral venous sample. The blood drawn through the Broviac catheter contained greater than or equal to 2000 colony-forming units per milliliter in six cases. Quantitative cultures in two patients with septicemia not attributable to the catheter yielded low colony counts in the catheter sample. Cultures of blood samples drawn through the catheter when a child was well were not helpful in predicting subsequent septicemia. The technique of inoculating blood directly onto agar plates is easily performed and superior to standard broth cultures, because it detected pathogens within 16 hours and identified infections with multiple organisms.

Pseudomonas aeruginosa bacteremia in children: analysis of trends in prevalence, antibiotic resistance and prognostic factors.

Objective. To determine the factors predisposing to Pseudomonas aeruginosa bacteremia as well as the prevalence, source of infection, outcome and prognostic factors in pediatric patients. Methods. Retrospective review of pediatric patients with P. aeruginosa bacteremia, at a large tertiary care hospital during a 6.5-year period. Results. Seventy patients with P. aeruginosa bacteremia were identified. The annual rate of P. aeruginosa bacteremia remained unchanged during the study period. Antibiotic susceptibility remained unchanged except for two patients with extensive burns who developed resistant strains. Underlying diseases were malignancy (50%), prematurity (6%), burns (7%) and others (37%). The overall mortality associated with P. aeruginosa bacteremia was 20%. The fatality rate was higher among the young infants (compared with older children) and those who received previous antibiotic therapy (P = 0.02). Mortality rate was higher in nosocomial than in community-acquired infections (25% compared with 11.5%). The mortality rate of low birth weight and burns patients was significantly higher when compared with oncology patients or other patients, 75 and 40% compared with 11 and 19%, P = 0.01. Multiple regression analysis revealed a correlation only between the underlying disease and mortality (P = 0.02). In the oncology patients the only significant risk factor for mortality was absolute neutrophil count ≤ 0.1 × 109/l (P = 0.06). Conclusion. P. aeruginosa bacteremia, although apparently not increasing in incidence and antibiotic resistance, is still a common serious complication in immunocompromised children with a high mortality rate. We conclude that the underlying disease is the main determinant of the clinical outcome.

Universal neonatal cytomegalovirus screening using saliva – Report of clinical experience

OBJECTIVES To analyze the results of a neonatal universal screen for congenital cytomegalovirus (CMV) using saliva real-time polymerase chain reaction (rt-PCR). STUDY DESIGN During one year (15/5/2011-15/5/2012), saliva was collected from 9845 infants (97% of 10,137 newborns). Viral DNA was extracted by Magna-Pure LC (Roche) and was tested for the presence of CMV IE and gB genes. Urine culture was collected from positive infants for confirmation. For all infants with congenital CMV maternal data were collected and head ultrasound, blood count, liver enzymes, retinal examination and auditory brainstem response testing were performed. Parents were notified in advance and had the option to avoid screening. The ethical committee approved retrospective analysis of the data. RESULTS Fifty six infants (0.57%) had a positive saliva assay. Of these, 47 were confirmed by urine rt-PCR and culture, in another one maternal sero-conversion was documented during pregnancy (48 infants). Twenty-eight mothers (28/47, 60%) had primary infection during pregnancy, 14 (30%) had non-primary infection, and no serological data were obtained from five (10%). Four infants (8.5%), two with prenatal diagnosis of CMV and normal fetal brain imaging and two born to mothers sero-positive before pregnancy, exhibited symptoms related to CMV and were offered antivirals. Hearing impairment was diagnosed in two infants (late onset HI in one case). CONCLUSIONS Saliva rt-PCR assay is a feasible and effective means of universal neonatal CMV screening that can detect affected infants who might benefit from treatment and follow-up. The long-term clinical significance of screening and its cost effectiveness are yet to be determined.

Placental transfer of maternal poliovirus antibodies in full-term and pre-term infants

This study was designed to investigate the placental transfer of maternal poliovirus antibodies in full-term and pre-term infants. Two hundred healthy, Israeli born mothers and their infants, were enrolled immediately after birth. The study population comprised two groups: a full-term group of 150 mothers and their infants, and a pre-term group of 50 mothers and their infants (gestational age < 35 weeks). Maternal and umbilical cord blood samples were taken in all cases. Antibody titers against the three poliovirus serotypes and a polio virus type 1 strain that caused an outbreak in 1988 (epidemic strain 1) were measured by a microneutralization system. The proportion of individuals with protective titers against each of the poliovirus types tested was slightly lower in the infants compared with their mothers. When protection to all strains combined was tested, the difference between mothers and infants was significant (P < 0.05). Transplacental transfer to epidemic strain 1 was less effective--12% of the premature infants were not protected against it at birth. The geometric mean titers against poliovirus types 1, 3 and epidemic type 1 strain were significantly lower in the pre-term group than in the full-term group. In both the full-term and pre-term groups there were significant linear correlations between the maternal and neonatal antibody titers for each of the polio viruses tested. For all poliovirus types, the transfer of maternal antibodies to the full-term infant was significantly higher than the transfer of maternal antibodies to the pre-term infant (P < 0.001). Owing to diminished transfer of maternal antibodies, pre-term infants are at greater risk of poliovirus infection.

THE IMMUNE RESPONSE OF PREMATURE INFANTS TO RECOMBINANT HEPATITIS B VACCINE WHEN BOTH INACTIVATED POLIOVIRUS AND RECOMBINANT HEPATITIS B VACCINES ARE GIVEN SOON AFTER BIRTH † 1324

THE IMMUNE RESPONSE OF PREMATURE INFANTS TO RECOMBINANT HEPATITIS B VACCINE WHEN BOTH INACTIVATED POLIOVIRUS AND RECOMBINANT HEPATITIS B VACCINES ARE GIVEN SOON AFTER BIRTH † 1324

SEPTICEMIA IN THE ABSENCE OF CRP ELEVATION

At the Childrens Center of the Mount Sinai Hospital quantitative measurements of serum C-reactive protein (CRP) are frequently made. We have performed more than 30,000 such tests since 1974. A serum CRP determination is made whenever a blood culture is obtained. This practice made it possible for us to assess the value of quantitative CRP measurement in the prediction of septicemia.Over a three-year period, 127 positive blood cultures were identified. In 18 episodes of septicemia in 17 patients (ages 2 weeks to 17 years) the initial CRP was ≤ 1.5 mg/dl. In 14 of these 18 episodes, it was ≤ 1 mg/dl. Three children (4 episodes) were on chemotherapy for malignancy. Three children died the day of the determinations. The remaining children had serious infections with a variety of different agents, including H. influenzae, S. pneumoniae, S. aureus, Ps. aerugenosa, group B streptococcus, salmonella species, K. pneumoniae, E. cloacae and candida species.Our data illustrate that a normal initial CRP value is not inconsistent with septicemia. Physicians using CRP measurements for diagnostic purposes should be aware of this.