Blood cultures from Bangladeshi children with septicaemia: an evaluation of conventional, lysis-direct plating and lysis-centrifugation methods

Biomarkers of endothelial dysfunction predict sepsis mortality in young infants: a matched case-control study

Background

Reducing death due to neonatal sepsis is a global health priority, however there are limited tools to facilitate early recognition and treatment. We hypothesized that measuring circulating biomarkers of endothelial function and integrity (i.e. Angiopoietin-Tie2 axis) would identify young infants with sepsis and predict their clinical outcome.

Methods

We conducted a matched case-control (1:3) study of 98 young infants aged 0–59 days of life presenting to a referral hospital in Bangladesh with suspected sepsis. Plasma levels of Ang-1, Ang-2, sICAM-1, and sVCAM-1 concentrations were measured at admission. The primary outcome was mortality (n = 18); the secondary outcome was bacteremia (n = 10).

Results

Ang-2 concentrations at presentation were higher among infants who subsequently died of sepsis compared to survivors (aOR 2.50, p = 0.024). Compared to surviving control infants, the Ang-2:Ang-1 ratio was higher among infants who died (aOR 2.29, p = 0.016) and in infants with bacteremia (aOR 5.72, p = 0.041), and there was an increased odds of death across Ang-2:Ang-1 ratio tertiles (aOR 4.82, p = 0.013).

Conclusions

This study provides new evidence linking the Angiopoietin-Tie2 pathway with mortality and bacteremia in young infants with suspected sepsis. If validated in additional studies, markers of the angiopoietin-Tie2 axis may have clinical utility in risk stratification of infants with suspected sepsis.

Electronic supplementary material

The online version of this article (10.1186/s12887-018-1087-x) contains supplementary material, which is available to authorized users.

Risk factors for sclerema neonatorum in preterm neonates in Bangladesh

BACKGROUND

This study presents a retrospective analysis of risk factors for sclerema neonatorum in preterm neonates in Bangladesh.

METHODS

Preterm neonates admitted to Dhaka Shishu Hospital in Bangladesh were enrolled in a clinical trial to evaluate the effects of topical treatment with skin barrier-enhancing emollients on prevention of sepsis and mortality. Four hundred ninety-seven neonates were enrolled in the study and 51 (10.3%) developed sclerema neonatorum. We explored risk factors for sclerema neonatorum by comparing patients with and without sclerema neonatorum. Diagnosis of sclerema neonatorum was based on the presence of uniform hardening of skin and subcutaneous tissues to the extent that the skin could not be pitted nor picked up and pinched into a fold. Cultures of blood and cerebrospinal fluid were obtained in all neonates with clinical suspicion of sepsis.

RESULTS

In multivariate analysis, lower maternal education (OR: 1.94; 95% CI: 1.02-3.69; P = 0.043), and signs of jaundice (OR: 2.82; 95% CI: 1.19-6.69; P = 0.018) and poor feeding (OR: 4.71; 95% CI: 1.02-21.74; P = 0.047) on admission were risk factors for developing sclerema neonatorum. The incidence rate ratio of sepsis in neonates who developed sclerema neonatorum was 1.81 (95% CI: 1.16-2.73; P = 0.004), primarily due to Gram-negative pathogens, and risk of death in infants with sclerema neonatorum was 46.5-fold higher (P < 0.001, 95% CI: 6.37-339.81) than for those without sclerema neonatorum.

CONCLUSIONS

Sclerema neonatorum was a relatively common, grave condition in this setting, heralded by poor feeding, jaundice, and bacteremia, and signaling the need for prompt antibiotic treatment.

Effectiveness of Haemophilus influenzae type B conjugate vaccine on prevention of pneumonia and meningitis in Bangladeshi children: a case-control study

BACKGROUND

Few Asian countries have introduced Haemophilus influenzae type b (Hib) conjugate vaccine because of its cost and uncertainty regarding disease burden.

METHODS

To estimate the effectiveness of Hib conjugate vaccine in preventing pneumonia and meningitis in children age <2 years, an incident case-control study was conducted in a birth cohort of about 68,000 infants in Dhaka city, Bangladesh. DPT vaccine was systematically replaced by a combined Hib-DPT vaccine in selected immunization centers of the study area. Four matched community- and 2 hospital-controls were randomly selected for each confirmed case of pneumonia and meningitis from the study area.

RESULTS

About 35% of the infants received each of the 3 doses of Hib-DPT vaccine. There were 2679 children who had a chest roentgenogram. For 475 children, a radiologist and a pediatrician independently identified substantial alveolar consolidation. Following at least 2 doses of Hib vaccine, the preventable fractions [95% confidence intervals (CI)] using community and hospital controls were 17% (-10% to 38%) and 35% (13% to 52%) respectively. Of these 475 cases, 2 radiologists with the World Health Organization concurred with the findings for 343 patients, yielding preventable fractions of 34% (6% to 53%) and 44% (20% to 61%). Fifteen confirmed Hib meningitis cases were identified; the preventable fractions (95% CI) using community and hospital controls, respectively, were 89% (28% to 100%) and 93% (53% to 100%).

CONCLUSIONS

The study documented that significant fractions of pneumonia and meningitis in Bangladeshi children age <2 years can be prevented by the Hib conjugate vaccine.

Ciprofloxacin treatment in preterm neonates in Bangladesh: lack of effects on growth and development

BACKGROUND

Quinolone-induced arthropathic toxicity in weight-bearing joints observed in juvenile animals during preclinical testing has largely restricted the routine use of ciprofloxacin in the pediatric age group. As histopathologic, radiologic and magnetic resonance imaging monitoring evidence has gathered supporting the safety of fluoroquinolones in children, many pediatricians have started to prescribe quinolones to some patients on a compassionate basis.

OBJECTIVE

The objective of this study was to ascertain the safety of ciprofloxacin in preterm neonates <33 weeks gestational age treated at Dhaka Shishu (Children) Hospital in Bangladesh.

METHODS

Long-term follow up was done to monitor the growth and development of preterm infants who were administered intravenous ciprofloxacin in the neonatal period. Ciprofloxacin was used only as a life-saving therapy in cases of sepsis produced by bacterial agents resistant to other antibiotics. Another group of preterm neonates with septicemia who were not exposed to ciprofloxacin, but effectively treated with other antibiotics and followed up, were matched with cases for gender, gestational age and birth weight and included as a comparison group. Forty-eight patients in the ciprofloxacin group and 66 patients in the comparison group were followed up for a mean of 24.7 +/- 18.5 months and 21.6 +/- 18.8 months, respectively.

RESULTS

No osteoarticular problems or joint deformities were observed in the ciprofloxacin group during treatment or follow up. No differences in growth and development between the groups were found.

CONCLUSIONS

Ciprofloxacin is a safe therapeutic option for newborns with sepsis produced by multiply resistant organisms.

Effect of topical treatment with skin barrier-enhancing emollients on nosocomial infections in preterm infants in Bangladesh: a randomised controlled trial

BACKGROUND

Infections and complications of prematurity are main causes of neonatal mortality. Very low birthweight premature infants have compromised skin barrier function, and are at especially high risk for serious infections and mortality. Our aim was to ascertain whether topical application of emollients to enhance skin barrier function would prevent nosocomial infections in this population.

METHODS

We randomly assigned infants born before week 33 of gestation after admission to Dhaka Shishu Hospital, Bangladesh, to daily massage with sunflower seed oil (n=159) or Aquaphor (petrolatum, mineral oil, mineral wax, lanolin alcohol; n=157). We then compared incidence of nosocomial infections among infants in these two groups with an untreated control group (n=181) by an intention-to-treat analysis.

FINDINGS

20 patients in the control group, and 22 in each of the treatment groups left the hospital early, but were included in the final analysis. Overall, infants treated with sunflower seed oil were 41% less likely to develop nosocomial infections than controls (adjusted incidence rate ratio [IRR] 0.59, 95% CI 0.37-0.96, p=0.032). Aquaphor did not significantly reduce the risk of infection (0.60, 0.35-1.03, p=0.065). No adverse events were seen.

INTERPRETATION

Our findings confirm that skin application of sunflower seed oil provides protection against nosocomial infections in preterm very low birthweight infants. The low cost, availability, simplicity, and effect of treatment make it an important intervention for very low birthweight infants admitted to hospital in developing countries.

Rapid identification and antibiotic susceptibility testing of Salmonella enterica serovar Typhi isolated from blood: implications for therapy

The turnaround time (TAT) for Salmonella enterica serovar Typhi identification and reporting of the antibiotic susceptibility profile was determined for 391 cases of typhoid fever, using the lysis direct plating or lysis centrifugation method of blood culture along with rapid antimicrobial susceptibility testing. The TAT was more rapid (TAT for 90% of the patients [TAT(90)] = 30 h; TAT(100) Collapse

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MESH Headings

• Adolescent
• Adult
• Anti-Bacterial Agents/pharmacology
• Anti-Bacterial Agents/therapeutic use
• Bacteremia/drug therapy
• Bacteremia/microbiology
• Blood/microbiology
• Centrifugation
• Child
• Culture Media
• Drug Resistance, Multiple, Bacterial
• Hemolysis
• Humans
• Microbial Sensitivity Tests/methods
• Salmonella typhi/classification
• Salmonella typhi/drug effects
• Time Factors
• Typhoid Fever/drug therapy
• Typhoid Fever/microbiology

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Grants Collapse

Affiliation(s)

S K Saha Department of Microbiology, Institute of Child Health, Dhaka Shishu Hospital, Dhaka, Bangladesh.
G L Darmstadt
A H Baqui
M Hanif
M Ruhulamin
M Santosham
T Nagatake
R E Black

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Typhoid fever in Bangladesh: implications for vaccination policy

OBJECTIVE

To describe the age-specific distribution of typhoid fever including the degree of Salmonella typhi bacteremia among patients evaluated at a large private diagnostic center in Bangladesh, a highly endemic area.

METHODS

We conducted a prospective-, passive- and laboratory-based study to identify patients with S. typhi bacteremia. Subjects (n = 4,650) from whom blood cultures were obtained during 16-month period were enrolled from private clinics and hospitals throughout Dhaka. Isolation and quantification of S. typhi from blood cultures were performed by the lysis direct plating/ centrifugation method.

RESULTS

Bacterial pathogens were recovered from blood of 538 of 4,650 patients (11.6%) evaluated. S. typhi was the single most common pathogen recovered, comprising nearly three-fourths of isolates (72.7%; 391 of 538). Isolation rate of S. typhi was highest in monsoon and summer seasons and lowest in winter months. The majority (54.5%; 213 of 391) of S. typhi isolates were from children who were younger than 5 years, and 27% (105 of 391) were from children in the first 2 years of life. The isolation rate was highest (17.4%, 68 of 486) in the second year of life. The number of bacteria in blood on the basis of colony-forming units per ml of blood by age group was inversely related to age.

CONCLUSIONS

Detection of S. typhi bacteremia in young children in Dhaka, Bangladesh, was considerably higher than previously appreciated, with a peak detection rate in children < or =2 years of age, indicating the need to reassess the age-specific burden of typhoid fever in the community on a regional basis. Contrary to current recommendations this study suggests that development of new vaccines should target infants and young children.

Worldwide Haemophilus influenzae type b disease at the beginning of the 21st century: global analysis of the disease burden 25 years after the use of the polysaccharide vaccine and a decade after the advent of conjugates

Vaccination against Haemophilus influenzae type b (Hib) diseases began a quarter of a century ago with a polysaccharide vaccine; this vaccine was followed by four different conjugates 10 years later. In this review, the burden of global Hib disease is quantified following this 25-year period of vaccine availability to determine the potential impact of conjugate vaccines. This task was accomplished by analysis of data available in 10 languages in 75 geographical regions of over 50 countries. All severe Hib diseases, not only meningitis, were characterized, and special attention was paid to the most vulnerable age group, i.e., children aged 0 to 4 years. Prior to vaccination, the weighted worldwide incidence of meningitis in patients younger than 5 years was 57/100,000, and for all Hib diseases except nonbacteremic pneumonia, it was 71/100,000, indicating 357,000 and 445,000 cases per year, respectively. At least 108,500 of these children died. For all age groups combined, there were 486,000 cases of Hib disease, excluding pneumonia, with 114,200 deaths and probably an equal number of sequelae per annum. If the figures for nonbacteremic pneumonia are included, a conservative estimate is that over 2.2 million cases of infection and 520,000 deaths from Hib disease occurred worldwide, but the true numbers might have been greater. Despite these large numbers and availability of safe and efficacious vaccines, only 38,000 cases annually are prevented-a meager 8% or less than a 2% reduction in cases, depending on whether nonbacteremic pneumonia is included in the calculations. Although vaccination has had great success in some affluent countries, the current level of activity has had a very small impact globally. The use of conjugates, preferably with a reduced number of doses and in combination with other vaccines or perhaps in fractional doses, should be extended to less privileged countries, where most Hib disease occurs.

Worldwide Haemophilus influenzae type b disease at the beginning of the 21st century: global analysis of the disease burden 25 years after the use of the polysaccharide vaccine and a decade after the advent of conjugates

Vaccination against Haemophilus influenzae type b (Hib) diseases began a quarter of a century ago with a polysaccharide vaccine; this vaccine was followed by four different conjugates 10 years later. In this review, the burden of global Hib disease is quantified following this 25-year period of vaccine availability to determine the potential impact of conjugate vaccines. This task was accomplished by analysis of data available in 10 languages in 75 geographical regions of over 50 countries. All severe Hib diseases, not only meningitis, were characterized, and special attention was paid to the most vulnerable age group, i.e., children aged 0 to 4 years. Prior to vaccination, the weighted worldwide incidence of meningitis in patients younger than 5 years was 57/100,000, and for all Hib diseases except nonbacteremic pneumonia, it was 71/100,000, indicating 357,000 and 445,000 cases per year, respectively. At least 108,500 of these children died. For all age groups combined, there were 486,000 cases of Hib disease, excluding pneumonia, with 114,200 deaths and probably an equal number of sequelae per annum. If the figures for nonbacteremic pneumonia are included, a conservative estimate is that over 2.2 million cases of infection and 520,000 deaths from Hib disease occurred worldwide, but the true numbers might have been greater. Despite these large numbers and availability of safe and efficacious vaccines, only 38,000 cases annually are prevented-a meager 8% or less than a 2% reduction in cases, depending on whether nonbacteremic pneumonia is included in the calculations. Although vaccination has had great success in some affluent countries, the current level of activity has had a very small impact globally. The use of conjugates, preferably with a reduced number of doses and in combination with other vaccines or perhaps in fractional doses, should be extended to less privileged countries, where most Hib disease occurs.

Interpretation of the Widal test in the diagnosis of typhoid fever in Bangladeshi children

The value of a Widal test in diagnosing typhoid fever was assessed in children aged between 1 and 10 years in Bangladesh. The test was done on sera specimens from 300 healthy school children, 100 patients with non-typhoidal febrile illness and 150 bacteriologically proven cases of typhoid fever. Salmonella typhi O and H agglutinin titres > 1:80 and > 1:160 were considered to be significant with 88% sensitivity and 98% specificity, respectively. Among the bacteriologically proven cases, 11.3% showed no response to either agglutinin, and in another 17.3% of cases there was no response for TO agglutinin. This study suggests that in children in an endemic area a positive Widal test is of considerable importance in diagnosing typhoid fever. Furthermore, negative results should be interpreted with caution and both the agglutinins must be considered equally important. Reliance on somatic (TO) antigen only will result in missed diagnosis.

Evaluation and comparison of different blood culture techniques for bacteriological isolation of Salmonella typhi and Brucella abortus

An experimental study was carried out to evaluate and compare various noncommercial methods of blood culture for the isolation of Salmonella typhi and Brucella abortus from fresh human blood samples that had been artificially inoculated with 1 to 50 microorganisms per ml of blood. The methods compared included the Ruiz-Castañeda blood culture, broth blood culture, leukocyte lysis and direct plating on agar (WBL-P), leukocyte lysis and filtration, Ficoll-Hypaque centrifugation and filtration, Ficoll-Hypaque centrifugation, and Ficoll-Hypaque centrifugation and leukocyte lysis methods. Results with the WBL-P technique showed that S. typhi was isolated in 18 h, and its recovery rate was 36.6% (calculated from the number of CFU recovered per milliliter versus the number inoculated). B. abortus was isolated in 48 h by the same technique, and its recovery rate was 48.8%. The isolation times for the other blood culture techniques were between 36 and 44 h for S. typhi and 66 h for B. abortus. The techniques which relied on filtering systems for the recovery of S. typhi and B. abortus performed poorly. The WBL-P technique for the isolation of S. typhi and B. abortus is faster than the other methods tested.