Prospective study of toxigenic Clostridium difficile in children given amoxicillin/clavulanate for otitis media

Antibiotics Not Associated with Shorter Duration or Reduced Severity of Acute Lower Respiratory Tract Infection

BACKGROUND

Antibiotic use remains common for the treatment of lower respiratory tract infections. The objective of this study was to evaluate the impact of antibiotic use on the duration and severity of acute lower respiratory tract infection (LRTI).

PARTICIPANTS

Adult patients presenting to US primary or urgent care sites with a chief complaint of cough and symptoms consistent with LRTI.

MAIN MEASURES

Collected data included demographics, comorbidities, symptoms, and 48 viral and bacterial respiratory pathogens by PCR. Severity of signs/symptoms was reported for up to 28 days using diaries and text messages. Interpolation was used where data were missing.

KEY RESULTS

Of 718 patients with baseline data, 29% had an antibiotic prescribed at baseline. The most common antibiotics were amoxicillin-clavulanate, azithromycin, doxycycline, and amoxicillin in 85% of patients. Provision of an antibiotic had no effect on the duration or overall severity of cough, including in patients with viral, bacterial, and mixed infections. Receipt of an antibiotic did reduce the likelihood of a follow-up visit (14.1% vs 8.2%, aOR 0.47, 95% CI 0.26-0.84), perhaps by removing the motivation of getting an antibiotic at a follow-up visit. However, they were also more likely to receive a systemic corticosteroid (31.9% vs 4.5%, p < 0.001) and were also more likely to receive an albuterol inhaler (22.7% vs 7.6%, p < 0.001). Patients believed that receiving an antibiotic would reduce the duration of their illness by nearly 4 days.

CONCLUSIONS

In this large prospective study in the US primary and urgent care setting, antibiotics had no measurable impact on the severity or duration of cough due to acute LRTI. Patients had unrealistic expectations regarding the duration of LRTI and the effect of antibiotics which should be the target of antibiotic stewardship efforts.

Bifidobacterium animalis subsp. lactis BB-12 Protects against Antibiotic-Induced Functional and Compositional Changes in Human Fecal Microbiome

The administration of broad-spectrum antibiotics is often associated with antibiotic-associated diarrhea (AAD), and impacts gastrointestinal tract homeostasis, as evidenced by the following: (a) an overall reduction in both the numbers and diversity of the gut microbiota, and (b) decreased short-chain fatty acid (SCFA) production. Evidence in humans that probiotics may enhance the recovery of microbiota populations after antibiotic treatment is equivocal, and few studies have addressed if probiotics improve the recovery of microbial metabolic function. Our aim was to determine if Bifidobacterium animalis subsp. lactis BB-12 (BB-12)-containing yogurt could protect against antibiotic-induced fecal SCFA and microbiota composition disruptions. We conducted a randomized, allocation-concealed, controlled trial of amoxicillin/clavulanate administration (days 1-7), in conjunction with either BB-12-containing or control yogurt (days 1-14). We measured the fecal levels of SCFAs and bacterial composition at baseline and days 7, 14, 21, and 30. Forty-two participants were randomly assigned to the BB-12 group, and 20 participants to the control group. Antibiotic treatment suppressed the fecal acetate levels in both the control and probiotic groups. Following the cessation of antibiotics, the fecal acetate levels in the probiotic group increased over the remainder of the study and returned to the baseline levels on day 30 (-1.6% baseline), whereas, in the control group, the acetate levels remained suppressed. Further, antibiotic treatment reduced the Shannon diversity of the gut microbiota, for all the study participants at day 7. The magnitude of this change was larger and more sustained in the control group compared to the probiotic group, which is consistent with the hypothesis that BB-12 enhanced microbiota recovery. There were no significant baseline clinical differences between the two groups. Concurrent administration of amoxicillin/clavulanate and BB-12 yogurt, to healthy subjects, was associated with a significantly smaller decrease in the fecal SCFA levels and a more stable taxonomic profile of the microbiota over time than the control group.

Effect of amoxicillin-clavulanic acid on clinical scores, intestinal microbiome, and amoxicillin-resistant Escherichia coli in dogs with uncomplicated acute diarrhea

Background

Despite limited evidence of efficacy, antibiotic treatment is still frequently prescribed in dogs with uncomplicated acute diarrhea (AD).

Objective

To assess whether amoxicillin‐clavulanic acid has a clinical benefit, an effect on the fecal microbiome, and the proportion of amoxicillin‐resistant Escherichia coli in dogs with AD.

Animals

Sixteen dogs with AD of <3 days duration.

Methods

Prospective, placebo‐controlled, double‐blinded study. Clinical scores were compared between client‐owned dogs randomly assigned to an antibiotic (AG) or a placebo (PG) group. The intestinal microbiome was analyzed using quantitative PCR assays. Amoxicillin‐resistant fecal E. coli were assessed semiquantitatively with microbiological methods.

Results

There was no difference in clinical recovery between treated dogs or controls (CADS index day 10: AG group median: 2 (range: 1‐3; CI [1.4; 2.6]); PG group median: 1.6 (range: 1‐3; CI [1.1; 2.4]); P > .99). All dogs gained normal clinical scores (CADS index ≤3) after 1 to 6 days (median 2 days) after presentation. There was no significant difference in the fecal dysbiosis index (during treatment: AG mean −2.6 (SD 3.0; CI [−5.1; 0.0]); PG mean −0.8 (SD 4.0; CI [−4.2; 2.5]; P > .99) or its bacterial taxa. The proportion of resistant fecal E. coli increased (to median: 100%; range: 35%‐100%) during treatment with amoxicillin‐clavulanic acid and was still increased (median: 10%; range 2%‐67%) 3 weeks after treatment, both of which were significantly higher proportions than in the placebo group for both time points (during treatment AG median 100% versus PG median 0.2% (P < .001); after treatment AG median 10% versus PG median 0.0% (P = .002)).

Conclusions and Clinical Importance

Our study suggests that treatment with amoxicillin‐clavulanic acid confers no clinical benefit to dogs with AD, but predisposes the development of amoxicillin‐resistant E. coli, which persist for as long as 3 weeks after treatment. These findings support international guideline recommendations that dogs with diarrhea should not be treated with antimicrobials unless there are signs of sepsis.

Reported rates of diarrhea following oral penicillin therapy in pediatric clinical trials

OBJECTIVES

Antibiotic-associated diarrhea (AAD) is a well-recognized adverse reaction to oral penicillins. This review analyzed the literature to determine the incidence of AAD following amoxicillin, amoxicillin/clavulanate, and penicillin V oral therapy in pediatric clinical trials.

METHODS

An advanced search was conducted in MEDLINE and Embase databases for articles in any language reporting the incidence of AAD following oral penicillin therapy for any indicated infection in children (0-17 years). The search was limited to clinical trials. Articles were excluded if treatment was related to chronic conditions, involved concomitant antimicrobials, or if the dose or number of patients was not specified.

RESULTS

Four hundred thirty-five articles relating to clinical trials were identified (307 from Embase; 128 from MEDLINE). Thirty-five articles reporting on 42 studies were included for analysis. The indications included acute otitis media, sinusitis, pharyngitis, and pneumonia. Thirty-three trials reported on amoxicillin/clavulanate, 6 on amoxicillin, and 3 on penicillin V. In total, the 42 trials included 7729 children who were treated with an oral penicillin. On average, 17.2% had AAD. Data were pooled for each penicillin. The AAD incidence was 19.8% for amoxicillin/clavulanate, 8.1% for amoxicillin, and 1.2% for penicillin V. The amoxicillin/clavulanate data were analyzed according to formulation: pooled-average. The incidence of ADD was 24.6% for the 4:1 formulation, 12.8% for the 7:1 formulation, 19.0% for the 8:1 formulation, and 20.2% for the 14:1 formulation.

CONCLUSIONS

These results demonstrate substantially increased incidence of AAD following use of amoxicillin/clavulanate, compared to use of amoxicillin and penicillin V, as well as varying AAD rates with diffierent amoxicillin/clavulanate formulations. These findings warrant consideration when prescribing. The underlying mechanisms of AAD in children remain unclear.

Clostridium difficile as a cause of healthcare-associated diarrhoea among children in Auckland, New Zealand: clinical and molecular epidemiology

We aimed to determine the incidence of Clostridium difficile infection (CDI), the molecular epidemiology of circulating C. difficile strains and risk factors for CDI among hospitalised children in the Auckland region. A cross-sectional study was undertaken of hospitalised children <15 years of age in two hospitals investigated for healthcare-associated diarrhoea between November 2011 and June 2012. Stool specimens were analysed for the presence of C. difficile using a two-step testing algorithm including polymerase chain reaction (PCR). C. difficile was cultured and PCR ribotyping performed. Demographic data, illness characteristics and risk factors were compared between children with and without CDI. Non-duplicate stool specimens were collected from 320 children with a median age of 1.2 years (range 3 days to 15 years). Forty-six patients (14 %) tested met the definition for CDI. The overall incidence of CDI was 2.0 per 10,000 bed days. The percentage of positive tests among neonates was only 2.6 %. PCR ribotyping showed a range of strains, with ribotype 014 being the most common. Significant risk factors for CDI were treatment with proton pump inhibitors [risk ratio (RR) 1.74, 95 % confidence interval (CI) 1.09-5.59; p = 0.002], presence of underlying malignancy (RR 2.71, 95 % CI 1.65-4.62; p = 0.001), receiving chemotherapy (RR 2.70, 95 % CI 1.41-4.83; p = 0.003) and exposure to antibiotics (RR 1.17, 95 % CI 0.99-1.17; p = 0.03). C. difficile is an important cause of healthcare-associated diarrhoea in this paediatric population. The notion that neonatal populations will always have high rates of colonisation with C. difficile may not be correct. Several risk factors associated with CDI among adults were also found to be significant.

Clostridium difficile infection in children: a comprehensive review

OBJECTIVE

To provide a comprehensive review of the literature relating to Clostridium difficile (C. difficile) infection (CDI) in the pediatric population.

METHODS

Two investigators conducted independent searches of PubMed, Web of Science, and Scopus until March 31st, 2013. All databases were searched using the terms 'Clostridium difficile infection', 'Clostridium difficile associated diarrhea' 'antibiotic associated diarrhea', 'C. difficile', in combination with 'pediatric' and 'paediatric'. Articles which discussed pediatric CDI were reviewed and relevant cross references also read and evaluated for inclusion. Selection bias could be a possible limitation of this approach.

FINDINGS

There is strong evidence for an increased incidence of pediatric CDI. Increasingly, the infection is being acquired from the community, often without a preceding history of antibiotic use. The severity of the disease has remained unchanged. Several medical conditions may be associated with the development of pediatric CDI. Infection prevention and control with antimicrobial stewardship are of paramount importance. It is important to consider the age of the child while testing for CDI. Traditional therapy with metronidazole or vancomycin remains the mainstay of treatment. Newer antibiotics such as fidaxomicin appear promising especially for the treatment of recurrent infection. Conservative surgical options may be a life-saving measure in severe or fulminant cases.

CONCLUSIONS

Pediatric providers should be cognizant of the increased incidence of CDI in children. Early and judicious testing coupled with the timely institution of therapy will help to secure better outcomes for this disease.

Effect of low-intensity focused ultrasound on the middle ear in a mouse model of acute otitis media

We hypothesized that low-intensity focused ultrasound (LIFU) increases vessel permeability and antibacterial drug activity in the mouse middle ear. We determined appropriate settings by applying LIFU to mouse ears with the external auditory canal filled with normal saline and performed histologic and immunohistologic examination. Acute otitis media was induced in mice with nontypable Haemophilus influenzae, and they were given ampicillin (50, 10, or 2 mg/kg) intraperitoneally once daily for 3 days with or without LIFU (1.0 W/cm(2), 20% duty cycle, 30 s). In the LIFU(+) groups receiving the 2- and 10-mg/kg doses, viable bacteria counts, number of inflammatory cells and IL-1β and TNF-α levels in middle ear effusion were significantly lower than in the LIFU(-) groups on the same doses. Severity of AOM also tended to be reduced more in the LIFU(+) groups than in the LIFU(-) groups. LIFU application with antibiotics may be effective for middle ear infection.

Severe ciprofloxacin-associated pseudomembranous colitis in an eight-year-old child

Clostridium difficile is the principal cause of antibiotic-associated diarrhea and pseudomembranous enterocolitis in children. A case of severe pseudomembranous colitis developing in an 8-year-old child who had received oral ciprofloxacin therapy as part of an investigational protocol is presented. The safety and efficacy of fluoroquinolones in children has not yet been established. Use of these antibiotics in children outside investigational protocols ("off-label" use) as oral antipseudomonas agents is discouraged.

Impact of Ketolides on Resistance Selection and Ecologic Effects during Treatment for Respiratory Tract Infections

Ketolides are a new class of antibacterials that have been specifically developed for the treatment of community-acquired respiratory tract infections in an era of increasing resistance among major etiologic pathogens. These agents possess several unique structural features, including a 3-keto function and a large aromatic side chain, that confer not only a mode of action that differentiates them from the macrolide class but also a reduced potential to induce--or select for--resistant strains. Studies also suggest that ketolides such as telithromycin have a lower ecologic impact on the body's microflora than agents such as clarithromycin and amoxicillin-clavulanate, potentially reducing the risk of emergence of resistant strains and the spread of such resistance to pathogenic species. Therefore, available evidence suggests that ketolides may not only provide important new treatment options in an era of increasing resistance but may also contribute to reducing the pressure for development of further resistance. Clearly, further studies are required to confirm this low resistance potential once the ketolide agents become more widely used in routine practice.

Amoxicillin/clavulanate for infections in infants and children: past, present and future

Chemical synthesis of the penicillin nucleus in the 1950s made introduction of a broad array of new and important antimicrobials, including ampicillin and amoxicillin, possible. Ampicillin was introduced in 1962 in oral and parenteral forms as the first of the semisynthetic penicillins to provide increased activity against Gram-negative bacteria. Amoxicillin replaced oral ampicillin beginning in 1974 because amoxicillin resulted in higher and more prolonged serum concentrations than did equivalent doses of ampicillin. Amoxicillin/clavulanate (Augmentin) was introduced in the United States in 1984 to enhance the activity of amoxicillin by addition of the beta-lactamase inhibitor, clavulanic acid. During the past 20 years, amoxicillin/clavulanate has proven effective for a variety of pediatric infectious diseases, particularly acute otitis media (AOM). In 2001, a new pediatric formulation, high dose amoxicillin/clavulanate (Augmentin ES-600) was approved for use in the United States. The high dose preparation addressed the needs of pediatricians by providing greater amounts of amoxicillin while maintaining the same daily dose of clavulanic acid as the regular strength formulation. Doubling the dose of amoxicillin for management of recurrent and persistent AOM was recommended in 1999 by the Centers for Disease Control and Prevention because of concern about the increased incidence of nonsusceptible strains of Streptococcus pneumoniae. The original formulation combined amoxicillin/clavulanate in a 4:1 ratio and was followed by a 7:1 ratio formulation. The high dose formulation (600 mg of amoxicillin per 5 ml) provides a 14:1 ratio of amoxicillin to clavulanate. Although management of AOM will likely undergo changes in the coming years, amoxicillin is expected to remain first line therapy for AOM. For children who fail initial therapy with amoxicillin, high dose amoxicillin/clavulanate, an oral cephalosporin or parenteral ceftriaxone is recommended.

Incidence and risk factors of oral antibiotic-associated diarrhea in an outpatient pediatric population

BACKGROUND

Little information is available on the epidemiologic characteristics of antibiotic-associated diarrhea (AAD) in children. The authors' aim was to evaluate the incidence of AAD in an outpatient pediatric population and to identify risk factors.

METHODS

Children aged 1 month to 15.4 years treated with oral antibiotics for a proven or suspected infection were enrolled from an ambulatory pediatric practice during an 11-month period. Parents recorded the daily frequency and characteristics of stools using a diary during the antibiotic treatment and for 1 week after it was stopped. An episode of diarrhea was defined by at least 3 soft or liquid stools/d for at least 2 consecutive days. Risk factors for AAD-age, type of antibiotic treatment, type of combined treatment, and site of infection-were analyzed.

RESULTS

Of 650 children included, 11% had an episode of AAD, lasting a mean of 4.0 +/- 3.0 days, beginning a mean of 5.3 +/- 3.5 days after the start of antibiotic treatment. No child was hospitalized because of AAD. The incidence of AAD was higher in children less than 2 years (18%) than in those more than 2 years (3%; P < 0.0001). The incidence of AAD was particularly high after administration of certain antibiotics (amoxicillin/clavulanate, 23%; P = 0.003 compared with other antibiotics). The type of combined treatment and site of infection did not influence the onset of AAD.

CONCLUSIONS

Antibiotic-associated diarrhea was common in these outpatient children, especially for those aged less than 2 years and after the prescription of certain antibiotics, particularly, the combination of amoxicillin/clavulanate.

Epidemiology, risk factors and treatments for antibiotic-associated diarrhea

Antibiotic-associated diarrhea (AAD) is a common complication of antibiotics and recent findings on the epidemiology, etiologies and treatment strategies are reviewed. Rates of AAD vary from 5 to 39% depending upon the specific type of antibiotic. The severity of AAD may include uncomplicated diarrhea, colitis or pseudomembranous colitis. The pathogenesis of AAD may be mediated through the disruption of the normal flora and overgrowth of pathogens or through metabolic imbalances. The impact of AAD is reflected by increased hospital stays, higher medical costs and increased rates of comorbidity. The key to decreasing these consequences is prompt diagnosis followed by effective treatment and institution of control measures.