Emergence and persistence of beta-lactamase-producing bacteria in the upper respiratory tract in children treated with beta-lactam antibiotics

β-Lactam-Resistant Streptococcus pneumoniae Dynamics Following Treatment: A Dose-Response Meta-analysis

BACKGROUND

Patient exposure to antibiotics promotes the emergence of drug-resistant pathogens. The aim of this study was to identify whether the temporal dynamics of resistance emergence at the individual-patient level were predictable for specific pathogen-drug classes.

METHODS

Following a systematic review, a novel robust error meta-regression method for dose-response meta-analysis was used to estimate the odds ratio (OR) for carrying resistant bacteria during and following treatment compared to baseline. Probability density functions fitted to the resulting dose-response curves were then used to optimize the period during and/or after treatment when resistant pathogens were most likely to be identified.

RESULTS

Studies of Streptococcus pneumoniae treatment with β-lactam antibiotics demonstrated a peak in resistance prevalence among patients 4 days after completing treatment with a 3.32-fold increase in odds (95% confidence interval [CI], 1.71-6.46). Resistance waned more gradually than it emerged, returning to preexposure levels 1 month after treatment (OR, 0.98 [95% CI, .55-1.75]). Patient isolation during the peak dose-response period would be expected to reduce the risk that a transmitted pathogen is resistant equivalently to a 50% longer isolation window timed from the first day of treatment.

CONCLUSIONS

Predictable temporal dynamics of resistance levels have implications both for surveillance and control.

Haemophilus influenzae Prevalence, Proportion of Capsulated Strains and Antibiotic Susceptibility During Colonization and Acute Otitis Media in Children, 2019-2020

BACKGROUND

The objective of this study was to determine the prevalence, proportion of encapsulated strains and antibiotic susceptibility of Haemophilus influenzae isolated from young children.

METHODS

Children, 6 months to 30 months old, were prospectively enrolled from September 2019 to September 2020 at Rochester, NY, pediatric clinics. H. influenzae isolates from nasopharynx (NP) at healthy visits and disease isolates from NP and middle ear fluid (MEF) at onset of acute otitis media (AOM) were characterized by capsular typing, β-lactamase production and antibiotic susceptibility.

RESULTS

Samples from 565 healthy visits and 130 AOM visits were collected. H. influenzae was detected 5.9% and 27% in the NP from healthy and AOM visits, respectively. In the MEF, H. influenzae was isolated in 43% of samples. Eight percent of H. influenzae isolates were encapsulated, 88% type f. Overall 39.7% of isolates were β-lactamase producing; 43% for MEF isolates. Ampicillin, trimethoprim/sulfamethoxazole, erythromycin and clarithromycin nonsusceptibility were found in more than 25% of isolates. None of the encapsulated H. influenzae isolates were positive for β-lactamase production or ampicillin nonsusceptibility. 9.2% of isolates were β-lactamase negative, ampicillin resistant (β-lactamase negative, ampicillin resistant + β-lactamase negative, ampicillin intermediate).

CONCLUSIONS

The prevalence of H. influenzae in the NP of young children is very low at times of health, but H. influenzae is highly prevalent in MEF at onset of AOM. Nontypeable H. influenzae accounts for >90% of all H. influenzae isolates. Type f predominated among encapsulated strains. β-lactamase production and antibiotic nonsusceptibility among H. influenzae strains isolated from the NP and MEF are common.

Resistance decay in individuals after antibiotic exposure in primary care: a systematic review and meta-analysis

BACKGROUND

Antibiotic resistance is an urgent global problem, but reversibility is poorly understood. We examined the development and decay of bacterial resistance in community patients after antibiotic use.

METHODS

This was a systematic review and meta-analysis. PubMed, EMBASE and CENTRAL (from inception to May 2017) were searched, with forward and backward citation searches of the identified studies. We contacted authors whose data were unclear, and of abstract-only reports, for further information. We considered controlled or times-series studies of patients in the community who were given antibiotics and where the subsequent prevalence of resistant bacteria was measured. Two authors extracted risk of bias and data. The meta-analysis used a fixed-effects model.

RESULTS

Of 24,492 articles screened, five controlled and 20 time-series studies (total 16,353 children and 1461 adults) were eligible. Resistance in Streptococcus pneumoniae initially increased fourfold after penicillin-class antibiotic exposure [odds ratio (OR) 4.2, 95% confidence interval (CI) 3.5-5.4], but this fell after 1 month (OR 1.7, 95% CI 1.3-2.1). After cephalosporin-class antibiotics, resistance increased (OR 2.2, 95%CI 1.7-2.9); and fell to (OR 1.6, 95% CI 1.2-2.3) at 1 month. After macrolide-class antibiotics, resistance increased (OR 3.8, 95% CI 1.9-7.6) and persisted for 1 month (OR 5.2, 95% CI 2.6-10.3) and 3 months (OR 8.1, 95% CI 4.6-14.2, from controlled studies and OR 2.3, 95% CI 0.6-9.4, from time-series studies). Resistance in Haemophilus influenzae after penicillins was not significantly increased (OR 1.3, 95% CI 0.9-1.9) initially but was at 1 month (OR 3.4, 95% CI 1.5-7.6), falling after 3 months (OR 1.0, 95% CI 0.5-2.2). Data were sparse for cephalosporins and macrolides. Resistance in Enterobacter increased post-exposure (OR 3.2, 95% CI 0.9-10.8, from controlled studies and OR 7.1, 95% CI 4.2-12, from time-series studies], but was lower after 1 month (OR 1.8, 95% CI 0.9-3.6).

CONCLUSIONS

Resistance generally increased soon after antibiotic use. For some antibiotic classes and bacteria, it partially diminished after 1 and 3 months, but longer-term data are lacking and urgently needed.

TRIAL REGISTRATION

PROSPERO CRD42015025499 .

Children with respiratory tract infections in Swedish primary care; prevalence of antibiotic resistance in common respiratory tract pathogens and relation to antibiotic consumption

BACKGROUND

The majority of antibiotics consumed in developed countries are prescribed in primary care. However, little is known about resistance levels in the primary care population.

METHOD

Nasopharyngeal cultures were obtained from children, 0-10 years of age, seeking care at their Primary Health Care Centre with symptoms of respiratory tract infection. Parental questionnaires were used to retrieve information about the child's previous antibiotic consumption.

RESULT

Cultures from 340 children were gathered. The level of resistant Haemophilus influenzae was low and the prevalence of penicillin non-susceptible pneumococci (PNSP MIC ≥ 0.125 mg/L) was 6% compared to 10% (p = 0.31) in corresponding cultures from children diagnosed at the local clinical microbiology laboratory. Antibiotic treatment within the previous 4 weeks predisposed for resistant bacteria in the nasopharynx, OR: 3.08, CI 95% (1.13-8.42).

CONCLUSION

Low prevalence of PNSP supports the use of phenoxymethylpenicillin as empirical treatment for childhood upper respiratory tract infections attending primary care in our setting. It is important that studies on resistance are performed in primary care populations to evaluate data from microbiological laboratories. Recent antibiotic treatment increases risk of bacterial resistance in children and continuous work to reduce unnecessary antibiotic prescribing should be prioritised.

Frequency of penicillin-resistant pneumococci in children is correlated to community utilization of antibiotics

OBJECTIVE

To study the impact of the utilization of antibiotics in children at the population level on the frequency of penicillin-nonsusceptible pneumococci (PNSP).

DESIGN

Children ages 0 to 6 years with a nasopharyngeal culture of PNSP were registered on place of residency in the 20 municipalities of the former Malmöhus County (since 1998 a part of Skåne County). Where possible the total number of nasopharyngeal cultures with growth of pneumococci was registered as well. All antibiotic prescriptions for 0- to 6-year-old children were analyzed in the 20 municipalities.

MAIN OUTCOME MEASURES

Correlation between the utilization of antibiotics and the frequency of PNSP in children at the municipality level.

RESULTS

The proportion of PNSP among all isolates of pneumococci from nasopharyngeal cultures varied between 0 and 49.5%. The antibiotic utilization in children varied among the 20 neighboring municipalities from 8.5 to 19.7 defined daily doses per 1000 children per day. The municipalities with high total utilization also had more frequent use of macrolides and broad spectrum antibiotics. The was a significant correlation between antibiotic use and the proportion of PNSP (correlation coefficient, 0.96; P = 0.002), and the correlation coefficients for trimethoprim-sulfamethoxazole, amoxicillins, macrolides and cephalosporins were significant at the 0.001 level. There was no significant correlation between the use of penicillin V and the frequency of PNSP. CONCLUSIONS. There was a significant correlation between the frequency of PNSP and the utilization of antibiotics in children at the population level.

Predicting bacteremia and bacteremic mortality in liver transplant recipients

Predictors of bacteremia and mortality in bacteremic liver transplant recipients were prospectively assessed. One hundred eleven consecutive episodes of fever or infections were documented in 59 patients over a 4-year period. Forty-nine percent (29 of 59 patients) of the patients had bacteremia, 39% (23 of 59 patients) had nonbacteremic infections, and 12% (7 of 59 patients) had fever of noninfectious cause. Primary (catheter-related) bacteremia (31%; 9 of 29 patients), pneumonia (24%; 7 of 29 patients), abdominal and/or biliary infections (14%; 4 of 29 patients), and wound infections (10%; 3 of 29 patients) were the predominant sources of bacteremia. Diabetes mellitus (odds ratio, 6.9; P =.03) and serum albumin level less than 3.0 mg/dL (odds ratio, 0.14; P =.02) were independently significant predictors of bacteremia compared with nonbacteremic infections. Mortality at 14 days was 28% (8 of 29 patients) in those with bacteremia compared with 4% (1 of 23 patients) in those with nonbacteremic infections and 0% (0 of 7) in patients with fever of noninfectious cause (P =.03). Intensive care unit stay at the time of bacteremia (100% v 47%; P =.005), absence of chills (0% v 53%; P =.005), lower temperature at the onset of bacteremia (99.2 degrees F v 101.5 degrees F; P =.009), lower maximum temperature during the course of bacteremia (99.3 degrees F v 102 degrees F, P =.008), greater serum bilirubin level (7.6 v 1.5 mg/dL; P =.024), presence of abnormal blood pressure (80% v 16%; P =. 0013), and greater prothrombin time (15.6 v 13.3 seconds; P =.013) were significantly predictive of greater mortality in the bacteremic patients. These data have implications for discerning the likelihood of bacteremia and initiation of empiric antibiotics pending cultures. Lack of febrile response in bacteremic liver transplant recipients portended a poorer outcome.

A population-based study of antibiotic prescriptions for Danish children

BACKGROUND

The aim of the study was to examine the use of systemic and topical antibiotics in relation to age and sex in Danish children.

METHODS

We used the Pharmacoepidemiological Prescription Database to identify the individual prescriptions of antibiotics provided for all 0-to 15-year-old children in North Jutland County, Denmark, during 1997. The population was approximately 95000 children.

RESULTS

We identified 44640 prescriptions for systemic antibiotics. The annual prescription rate was highest in the 1- to 2-year-olds, with 945 prescriptions/1000 children/year. One-half of these children received at least 1 prescription, and 12% received 3 or more prescriptions. Among the 11- to 15-year-old children 17% received one or more prescriptions. Overall 88% of the prescriptions were penicillins and 10% were macrolides. In children younger than 3 years 57% of prescriptions were for broad spectrum penicillins, but in children older than 6 years penicillin V was the most frequently used antibiotic. We identified 12 661 prescriptions for topical antibiotics used in eye infections. The prescription rate peaked in the 1- to 2-year-old children, one-third of whom received at least 1 prescription.

CONCLUSIONS

Almost two-thirds of the 0- to 2-year-old children in the population were treated with either systemic or topical antibiotics during 1 year. Physicians prescribe mostly penicillins, but the proportion of broad spectrum penicillins for young children was so high, however, that enforcement of national guidelines should be reconsidered.

Eradication of penicillin-resistant pneumococci in the nasopharynx with antibiotic combinations including rifampicin: experiences from the South Swedish Pneumococcal Intervention Project

39 children with prolonged nasopharyngeal carriage (48-328 days) of intermediately to highly penicillin-resistant pneumococci (PRP) were treated for 7 days with rifampicin in combination with amoxicillin (n = 18) erythromycin (n = 17) or clindamycin (n = 4), according to resistance pattern. In all children, except for 1 carrying a rifampicin-resistant strain, control cultures from the nasopharynx 1-2 weeks after the last antibiotic dosage, yielded no growth of PRP. In 2 brothers, PRP with the same serogroup and resistance pattern were found in nasopharynx 10 weeks after the antibiotic treatment. These preliminary findings indicate that antibiotic regimens including rifampicin are effective in eradicating nasopharyngeal carriage, but reappearance of the same strain may occur after several weeks. Such treatments should be given with caution due to the risk of selecting rifampicin-resistant strains. Further controlled studies are needed to determine the optimal combination of antibiotics and appropriate duration of therapy.

Prescriptions of antibiotics for children. Prescribing habits of district, hospital, and private physicians

OBJECTIVE

To study how different categories of physicians prescribe antibiotics for children with respiratory tract infections.

DESIGN

Prescriptions of antibiotics for children less than 15 years of age were registered at the pharmacies in the municipality of Växjö during the month of March from 1990 to 1993.

SUBJECTS

Three categories of physicians were studied: district, hospital, and private. They made 3047 prescriptions for one of the following groups of antibiotics: penicillin V, ampicillin derivatives, erythromycin or other macrolides, and peroral cephalosporins.

MAIN OUTCOME MEASURES

The choice and cost of drug for each physician category. The proportion of prescriptions made by district physicians in relation to distance from town centre and doctor density in local health centre.

RESULTS

The district physicians used penicillin V more frequently (70% of prescriptions) than the other categories of physicians (50% and 19%), but ampicillin derivatives and cephalosporins less frequently. District physicians had a lower cost per prescription in general (SEK 92) than hospital physicians (SEK 110) and private physicians (SEK 175). The proportion of prescriptions issued by district physicians increased with increasing distance from the town centre and with higher doctor density in the local health centre.

CONCLUSION

District physicians use more penicillin V, and have a lower cost per prescription, than other physicians. This might be due to differing infectious disease panoramas, but can also reflect differences in practice and attitudes.

Whether to transfer? Factors associated with hospitalization and outcome of elderly long-term care patients with pneumonia

OBJECTIVE

To determine factors associated with the decision to treat elderly long-term care patients with pneumonia in the hospital vs in the long-term care facility (LTCF) and factors associated with patient outcomes.

DESIGN

Retrospective cohort study.

SETTING

Hebrew Rehabilitation Center for Aged.

PATIENTS

Nursing home residents who had an episode of pneumonia, defined as a new respiratory sign or symptom and a new infiltrate.

MEASUREMENTS AND MAIN RESULTS

The majority of the 316 pneumonia episodes (78%) were managed in the LTCF, most (77%) with oral antibiotics. Both patient-related factors, such as elevated respiratory rate, and non-patient-related factors, such as evening evaluation, were associated with hospitalization. No patient who had a do-not-hospitalize (DNH) order was hospitalized. Equal proportions of patients given LTCF therapy (87%) and hospital therapy (88%) survived. Elevated respiratory rate was associated with dying from pneumonia in the LTCF but not in the hospital. Dependent functional status was associated with dying from pneumonia in both sites.

CONCLUSIONS

Many episodes of pneumonia can be managed in the LTCF with oral antibiotics. Because, in the absence of DNH orders, both patient-related and non-patient-related factors are associated with hospital transfer, discussion regarding preferences for hospitalization should occur prior to the development of an acute illness. A high respiratory rate may be a good marker for those LTCF patients requiring hospitalization. Dependent functional status may be a good marker for those LTCF patients unlikely to benefit from hospital transfer.

Characterization of cell-bound papain-soluble beta-lactamases in BRO-1 and BRO-2 producing strains of Moraxella (Branhamella) catarrhalis and Moraxella nonliquefaciens

In Moraxella (Branhamella) catarrhalis and Moraxella nonliquefaciens strains isolated from clinical specimens in the south of Sweden two variants of beta-lactamase were distinguished by isoelectric focusing (IEF). The BRO-1 (Ravasio type) enzyme was the most common in Branhamella catarrhalis, constituting about 90% of the beta-lactamase found in this species, while the BRO-2 enzyme (1908 type) was as common as BRO-1 in Moraxella nonliquefaciens. The determinants mediating the production of BRO-1 and BRO-2 were both transferable by conjugation. Cell-bound beta-lactamase from reference strains producing BRO-1 and BRO-2 could be solubilized by papain digestion. The isoelectric point of the solubilized enzymes differed distinctly between BRO-1 (pI 6.5) and BRO-2 (pI 6.9). The molecular species of BRO-1 and BRO-2 released by papain digestion were purified by affinity chromatography with phenylboronic acid agarose gel. They had identical molecular weights of approximately 28,000. Their kinetic constants were indistinguishable for a number of substrates and beta-lactamase inhibitors.

Production of betalactamase by respiratory tract bacteria in children: relationship to antibiotic use

Sales of antibiotics have increased in Sweden during the past decade. This has been paralleled by an increase in the frequency of beta-lactamase-producing respiratory tract bacteria. To investigate the effects of regional differences in use of antibiotics on beta-lactamase production in respiratory tract bacteria, we collected nasopharyngeal specimens and information about antibiotic use from 1133 children attending day-care centres in four rural municipalities with low use, and one urban municipality with high use of antibiotics, use being assessed from pharmacy sales. The frequency of beta-lactamase production among isolates of Branhamella catarrhalis and Moraxella nonliquefaciens was significantly higher in the urban municipality. This appeared to be a long-term ecological effect of differences in the level of use of antibiotics between the urban and rural populations, rather than an effect of recent antibiotic treatment of individual patients.

Beta-lactamase production in Branhamella catarrhalis isolated from lower respiratory tract secretions in Danish children: an increasing problem

Findings in specimens from the lower respiratory tract of children were reviewed retrospectively in order to assess the rate of Branhamella catarrhalis and beta-lactamase production. B. catarrhalis was isolated in 139 of 756 samples (18.4%) in 1986 and 211 of 723 samples (29.2%) in 1989. Beta-lactamase production was found in 55.6% of B. catarrhalis strains in 1986 and 80.1% in 1989 (p less than 0.001). Prevalence of beta-lactamase in B. catarrhalis has now reached the same level in Europe as in the USA.