Severe hepatic cholestasis after treatment with amoxicillin/clavulanic acid.

Amoxicillin/clavulanate is a commonly used antibiotic. Though relatively rare, amoxicillin/clavulanate carries the highest incidence of idiosyncratic drug-induced liver disease. This case report presents an 80-year-old woman treated for simple respiratory tract infection with amoxicillin/clavulanate who was subsequently hospitalized with malaise and icterus and a biochemical cholestatic pattern with high alkaline phosphatase and bilirubin. Diagnostically challenging, ultimately, liver biopsy revealed drug-induced liver injury with a fatal course after attempt of supportive, symptomatic treatment.

No evidence of difference in mortality with amoxicillin versus co-amoxiclav for hospital treatment of community-acquired pneumonia.

OBJECTIVES: Current guidelines recommend broad-spectrum antibiotics for high-severity community-acquired pneumonia (CAP), potentially contributing to antimicrobial resistance (AMR). We aim to compare outcomes in CAP patients treated with amoxicillin (narrow-spectrum) versus co-amoxiclav (broad-spectrum), to understand if narrow-spectrum antibiotics could be used more widely. METHODS: We analysed electronic health records from adults (≥16 y) admitted to hospital with a primary diagnosis of pneumonia between 01-January-2016 and 30-September-2023 in Oxfordshire, United Kingdom. Patients receiving baseline ([-12 h,+24 h] from admission) amoxicillin or co-amoxiclav were included. The association between 30-day all-cause mortality and baseline antibiotic was examined using propensity score (PS) matching and inverse probability treatment weighting (IPTW) to address confounding by baseline characteristics and disease severity. Subgroup analyses by disease severity and sensitivity analyses with missing covariates imputed were also conducted. RESULTS: Among 16,072 admissions with a primary diagnosis of pneumonia, 9685 received either baseline amoxicillin or co-amoxiclav. There was no evidence of a difference in 30-day mortality between patients receiving initial co-amoxiclav vs. amoxicillin (PS matching: marginal odds ratio 0.97 [0.76-1.27], p = 0.61; IPTW: 1.02 [0.78-1.33], p = 0.87). Results remained similar across stratified analyses of mild, moderate, and severe pneumonia. Results were also similar with missing data imputed. There was also no evidence of an association between 30-day mortality and use of additional macrolides or additional doxycycline. CONCLUSIONS: There was no evidence of co-amoxiclav being advantageous over amoxicillin for treatment of CAP in 30-day mortality at a population-level, regardless of disease severity. Wider use of narrow-spectrum empirical treatment of moderate/severe CAP should be considered to curb potential for AMR.

Amoxicillin/clavulanate in combination with rifampicin/clarithromycin is bactericidal against Mycobacterium ulcerans.

BACKGROUND: Buruli ulcer (BU) is a skin neglected tropical disease (NTD) caused by Mycobacterium ulcerans. WHO-recommended treatment requires 8-weeks of daily rifampicin (RIF) and clarithromycin (CLA) with wound care. Treatment compliance may be challenging due to socioeconomic determinants. Previous minimum Inhibitory Concentration and checkerboard assays showed that amoxicillin/clavulanate (AMX/CLV) combined with RIF+CLA were synergistic against M. ulcerans. However, in vitro time kill assays (TKA) are a better approach to understand the antimicrobial activity of a drug over time. Colony forming units (CFU) enumeration is the in vitro reference method to measure bacterial load, although this is a time-consuming method due to the slow growth of M. ulcerans. The aim of this study was to assess the in vitro activity of RIF, CLA and AMX/CLV combinations against M. ulcerans clinical isolates by TKA, while comparing four methodologies: CFU enumeration, luminescence by relative light unit (RLU) and optical density (at 600 nm) measurements, and 16S rRNA/IS2404 genes quantification. METHODOLOGY/PRINCIPAL FINDINGS: TKA of RIF, CLA and AMX/CLV alone and in combination were performed against different M. ulcerans clinical isolates. Bacterial loads were quantified with different methodologies after 1, 3, 7, 10, 14, 21 and 28 days of treatment. RIF+AMX/CLV and the triple RIF+CLA+AMX/CLV combinations were bactericidal and more effective in vitro than the currently used RIF+CLA combination to treat BU. All methodologies except IS2404 quantitative PCR provided similar results with a good correlation with CFU enumeration. Measuring luminescence (RLU) was the most cost-effective methodology to quantify M. ulcerans bacterial loads in in vitro TKA. CONCLUSIONS/SIGNIFICANCE: Our study suggests that alternative and faster TKA methodologies can be used in BU research instead of the cumbersome CFU quantification method. These results provide an in vitro microbiological support to of the BLMs4BU clinical trial (NCT05169554, PACTR202209521256638) to shorten BU treatment.

Effect of tebipenem pivoxil hydrobromide on the normal gut microbiota of a healthy adult population in Sweden: a randomised controlled trial.

BACKGROUND: Antimicrobials cause perturbations in the composition and diversity of the host microbiome. We aimed to compare gut microbiome perturbations caused by oral tebipenem pivoxil hydrobromide (a novel carbapenem) and by amoxicillin-clavulanic acid (an orally administered ß-lactam-ß-lactam inhibitor combination widely used in clinical practice). METHODS: We did a phase 1, single-centre, randomised, parallel-group, active-control trial to evaluate the effect of tebipenem pivoxil hydrobromide on the human gut microbiota. Healthy participants aged 18 years or older with no documented illnesses during recruitment were enrolled at Karolinska University Hospital (Stockholm, Sweden). Study participants were stratified by sex and block-randomised in a 1:1 ratio to treatment with either tebipenem pivoxil hydrobromide (600 mg orally every 8 h) or amoxicillin-clavulanic acid (500 mg amoxicillin and 125 mg clavulanic acid orally every 8 h). The study included 10 days of treatment (days 1-10) and four follow-up visits (days 14, 21, 90, and 180). The trial was open-label for clinical investigators and patients, but masked for microbiology investigators. Faecal samples were collected at all visits. Sequencing of 16S rDNA was used to measure the diversity metrics, and quantitative culture to quantify selected taxa. The primary outcomes were changes in the α and ß diversity and log count of colony-forming units for selected taxa between samples compared with baseline (day 1), and whether any changes reverted during the follow-up period. The analyses were done in the intention-to-treat population. This study was registered with ClinicalTrials.gov (NCT04376554). FINDINGS: The study was conducted between Jan 23, 2020, and April 6, 2021. 49 volunteers were screened for eligibility, among whom 30 evaluable participants (14 men and 16 women) were assigned: 15 (50%) to the tebipenem pivoxil hydrobromide group and 15 (50%) to the amoxicillin-clavulanic acid group. Baseline characteristics were similar between groups. Complete follow-up was available for all participants, and all participants except one completed treatment as assigned. The diversity metrics showed significant changes from baseline during the treatment period. Significant decreases in richness were observed on days 4-10 (p≤0·0011) in the amoxicillin-clavulanic acid group and on days 4-14 (p≤0·0019) in the tebipenem pivoxil hydrobromide group. Similarly, evenness was significantly decreased during treatment in the amoxicillin-clavulanic acid group (day 4, p=0·030) and the tebipenem pivoxil hydrobromide group (days 4-10, p<0·0001) compared with baseline. Quantitative cultures showed significant decreases in Enterobacterales (days 4-7, p≤0·0030), Enterococcus spp (days 4-14, p=0·025 to p<0·0001), Bifidobacterium spp (days 2-4, p≤0·026), and Bacteroides spp (days 4-10, p≤0·030) in the tebipenem pivoxil hydrobromide group. Similarly, in amoxicillin-clavulanic acid recipients, significant changes were observed in Enterobacterales (days 4-10, p≤0·048), Bifidobacterium spp (days 2-4, p≤0·013), and Lactobacillus spp (days 2-4, p≤0·020). Samples from the follow-up period were not significantly different from those at baseline in ß diversity analysis (PERMANOVA, p>0·99). By the end of the study, no significant change was observed compared with baseline in either group. There were no deaths or severe adverse events. INTERPRETATION: The impact of tebipenem pivoxil hydrobromide on the gut microbiome was similar to that of amoxicillin-clavulanic acid. The safety of antibiotic use with regard to the microbiome should be given attention, as dysbiosis is associated with health and disease. FUNDING: Spero Therapeutics.

Clinical Outcomes Associated with Amoxicillin Treatment for Acute Otitis Media in Children.

BACKGROUND: Acute otitis media (AOM) is the most common reason children are prescribed antibiotics. Bacteria that produce beta-lactamase are an increasingly frequent cause of AOM and may be resistant to amoxicillin, the currently recommended treatment for AOM. We aimed to evaluate the clinical outcomes of children treated with amoxicillin for AOM and assessed whether outcomes vary by infecting pathogen or beta-lactamase production. METHODS: 205 children 6-35 months old diagnosed with AOM and prescribed amoxicillin were included. Bacterial culture and qualitative multiplex real-time polymerase chain reaction were performed on nasopharyngeal swabs collected at enrollment. Parents completed surveys assessing symptoms, antibiotic adherence, and potential adverse events. The primary outcome was treatment failure with amoxicillin. Secondary outcomes included recurrence, symptom improvement, resolution, and adverse drug events (ADE). RESULTS: 8 children (5.4%) experienced treatment failure and 14 (6.8%) had recurrence. By day 5, 152 (74.1%) children had symptom improvement and 97 (47.3%) had resolution. Parents reported ADE for 56 (27.3%) children. Among 149 children who did not take any amoxicillin before enrollment, 98 (65.8%) had one or more beta-lactamase-producing bacteria. Common bacterial otopathogens were Moraxella catarrhalis (79, 53.0%), Streptococcus pneumoniae (51, 34.2%), Haemophilus influenzae (30, 20.1%), and Staphylococcus aureus (21, 14.1%). Treatment failure did not differ between children that did (5, 5.1%) and did not (3, 5.9%) have beta-lactamase-producing otopathogens (p = .05). CONCLUSIONS: Among children diagnosed with AOM treated with amoxicillin, treatment failure was uncommon and did not differ by pathogen or beta-lactamase production. These data support guidance recommending amoxicillin despite an increasing prevalence of beta-lactamase-producing bacteria.

[Skin abscess caused by Actinomyces radingae]. / Hautabszess verursacht durch Actinomyces radingae.

We report a 77-year-old man with a skin abscess caused by Actinomyces radingae. Targeted antibiotic therapy with amoxicillin/clavulanic acid for 6 weeks resulted in clearing of the infection. A. radingae is a rare pathogenic agent of skin and soft tissue infections. As with other Actinomyces infections, the early identification of the pathogen and specific antibiotic therapy is crucial for successful resolution of the infection because of the chronic course and the long treatment time needed. Usually, A. radingae is sensitive to ß­lactam antibiotics.

Acute pyelonephritis in cats is frequently caused by Escherichia coli resistant to potentiated penicillins but has a better prognosis than other causes of acute kidney injury.

OBJECTIVE: To describe the clinical findings, microbiological data, treatment, and outcome of a population of cats with suspected acute pyelonephritis (APN). ANIMALS: 32 client-owned cats. CLINICAL PRESENTATION AND PROCEDURES: Retrospective case series from 2 veterinary teaching hospitals between January 1, 2014, and December 31, 2020. Cats were included if they had a positive bacterial urine culture and a clinical diagnosis of acute kidney injury. RESULTS: Older female cats with underlying chronic kidney disease have a higher probability to develop bacterial culture-positive acute kidney injury or APN. Escherichia coli was the most commonly cultured bacterial species, and E coli isolates with susceptibility testing were resistant to amoxicillin-clavulanate but susceptible to fluoroquinolones or third-generation cephalosporins. Of the 20 cats with available follow-up information in the medical record, 14 were alive at 3 months after hospital discharge. Markers of renal function including creatinine (P = .008), BUN (P = .005), and phosphorus (P < .001) at the time of presentation were all higher in nonsurvivors compared with survivors. CLINICAL RELEVANCE: The survival rate with feline APN is higher than previous reports of acute kidney injury when all etiologies are considered. Nonsurvivors had more pronounced azotemia upon initial presentation. Amoxicillin-clavulanate was a poor empirical antimicrobial in this cohort based on the microbiological data.

Antimicrobial therapy in the management of odontogenic infections: the penicillin-allergic patient.

This retrospective analysis was performed to investigate whether clindamycin remains the preferred antibiotic for penicillin-allergic patients with odontogenic infections. The medical records of 311 patients admitted to the study department with odontogenic infections between 2018 and 2022 and treated with either intravenous amoxicillin-clavulanic acid (Augmentin) or intravenous clindamycin were analyzed. The Augmentin-treated group included 268 patients (86.2%) and the clindamycin-treated group included 43 patients (13.8%). Severity parameters did not differ significantly between the two groups, except for a higher prevalence of abscesses in the clindamycin-treated group (58.1% vs 41.0% in the Augmentin-treated group; P = 0.035). The clindamycin-treated group required a longer duration of intravenous antibiotics (P = 0.001) and had a higher rate of treatment failure (14.0% vs 2.2%; P = 0.002) when compared to the Augmentin-treated group, with a seven-fold increased risk of treatment failure. Moreover, significantly more isolated organisms in the clindamycin-treated group were resistant to clindamycin (P = 0.015); these were all Streptococcus anginosus group. Given the higher risk of treatment failure with clindamycin, it is necessary to choose the antibiotic treatment for penicillin-allergic patients carefully. A detailed history and allergy testing followed by combination therapy is recommended, especially in severe cases.

Comparative efficacy and optimal duration of first-line antibiotic regimens for acute otitis media in children and adolescents: a systematic review and network meta-analysis of 89 randomized clinical trials.

INTRODUCTION: Antibiotic use for acute otitis media (AOM) is one of the major sources of antimicrobial resistance. However, the effective minimal antibiotic duration for AOM remains unclear. Moreover, guidelines often recommend broad ranges (5-10 days) of antibiotic use, yet the clinical impact of such a wide window has not been assessed. METHODS: We systematically searched PubMed/MEDLINE, Embase, Scopus, Web of Science, and Cochrane Library from database inception to 6 October 2021. Network meta-analysis was conducted on randomized controlled trials that assessed antibiotic treatment for AOM in children (PROSPERO CRD42020196107). RESULTS: For amoxicillin and amoxicillin-clavulanate, 7-day regimens were noninferior to 10-day regimens in clinical responses [amoxicillin: risk ratio (RR) 0.919 (95% CI 0.820-1.031), amoxicillin-clavulanate: RR 1.108 (0.957-1.282)], except for ≤ 2 years. For the third-generation cephalosporins, 7-day and 10-day regimens had similar clinical responses compared to placebo [7-day: RR 1.420 (1.190-1.694), 10-day: RR 1.238 (1.125-1.362) compared to placebo]. However, 5-day regimens of amoxicillin-clavulanate and third-generation cephalosporins were inferior to 10-day regimens. Compared to amoxicillin, a shorter treatment duration was tolerable with amoxicillin-clavulanate. CONCLUSIONS: Our findings indicated that 10 days of antibiotic use may be unnecessarily long, while the treatment duration should be longer than 5 days. Otherwise, 5-day regimens would be sufficient for a modest treatment goal. Our findings revealed that the current wide range of recommended antibiotic durations may have influenced the clinical outcome of AOM, and a narrower antibiotic duration window should be re-established.

Prophylactic therapy for prevention of surgical site infection after extraction of third molar: An overview of reviews

Background: To compare the effect of different prophylactic therapies on prevention of surgical site infection after extraction of third molars with different degree of impaction. Material and Methods: Systematic reviews and meta-analyses evaluating the effect of different prophylactic therapies on prevention of surgical site infection after extraction of third molars were included. An electronic search was performed in PubMed, EMBASE, and the Cochrane Database of Systematic reviews. AMSTAR 2 tool was used to evaluate the confidence in results from the included reviews. Descriptive analyses were performed. Results: Six reviews were included. A significant benefit of different antibiotics to the prevention of site infection after extraction of third molars was reported. Amoxicillin/amoxicillin clavulanic acid could significantly reduce the rate of surgical site infection versus placebo. Chlorhexidine gel could significantly reduce the frequency of alveolar osteitis versus placebo. Conclusions: Based on the limited evidence, there is a significant benefit of prophylactic therapy while the comparative effect of different types of prophylactic regimes are controversial. (AU)

Efficacy of Raphamin against Pneumococcal Infection: a Preclinical Study.

The aim of the study was to evaluate the activity of Raphamin in a model of non-lethal pneumococcal infection caused by Streptococcus pneumoniae 3 in BALB/c mice. The drug or placebo was administered intragastrically 3 days prior to infection, 2 h before and 2 h post infection, and then for 3 full days, alone or in combination with antibiotic (amoxicil-lin/clavulanic acid). Raphamin monotherapy significantly decreased bacterial load in the lungs in comparison with placebo (p<0.05) which was comparable to the effect in antibiotic alone or combined with Raphamin. Raphamin prevented reproduction of Streptococcus pneumoniae in the lower respiratory tract and its combination with the antibiotic was safe and did not reduce the efficacy of amoxicillin/clavulanic acid.

Non-operative treatment of acute appendicitis in children: clinical efficacy of amoxicillin-clavulanic acid in a retrospective single-centre study.

BACKGROUND: The success rate of non-operative treatment (NOT) of acute uncomplicated appendicitis (AUA) in children varies from 65% to 95%. There are no recommendations on the appropriate antibiotic therapy. OBJECTIVE: To determine the clinical efficacy of amoxicillin-clavulanic acid for NOT of AUA in children. METHODS: Design: Cross-sectional study in a single medical centre. SETTINGS: Emergency department and Paediatric Visceral Surgery department of the Children Hospital in Toulouse, France. PATIENTS: Patients 5-15 years old who were diagnosed with appendicitis, (1) With abdominal pain and a first episode of acute appendicitis, (2) With no radiological or ultrasound evidence of appendicolith, appendiceal perforation, pelvic abscess nor peritonitis, and (3) With non-septic general aspect, were included. INTERVENTIONS: NOT consisted of hospital admission. The antibiotic treatment was a combination of amoxicillin and clavulanic acid (80 mg/kg/day of amoxicillin): intravenous regimen during 48 hours followed by oral route during 7 days. MAIN OUTCOME MEASURE: Success rate of amoxicillin-clavulanic acid NOT in children with AUA at 2 years. RESULTS: The initial success rate of amoxicillin-clavulanic acid NOT in children with AUA was 100% (104/104 patients). The success rate at 2 years was 85.6% (89/104) at discharge. None of the 15 patients who underwent surgery after recurrence of appendicitis presented with peritonitis, appendiceal perforation nor pelvic abscess. CONCLUSION: Narrowed antibiotic therapy with amoxicillin and clavulanic acid seems to be an alternative to surgery in children with AUA. It is necessary to wait for the results of ongoing studies to confirm these results.

Association of antimicrobial perioperative prophylaxis with cefuroxime plus metronidazole or amoxicillin/clavulanic acid and surgical site infections in colorectal surgery.

OBJECTIVE: To compare intravenous (IV) amoxicillin/clavulanic acid (A/CA) to IV cefuroxime plus metronidazole (C + M) for preventing surgical site infections (SSI) in colorectal surgery. BACKGROUND: Given their spectra that include most Enterobacterales and anaerobes, C + M is commonly recommended as prophylaxis of SSI in colorectal surgery. A/CA offers good coverage of Enterobacterales and anaerobes as well, but, in contrast to C + M, it also includes Enterococcus faecalis which is also isolated from patients with SSI and could trigger anastomotic leakage. METHODS: Data from a Swiss SSI surveillance program were used to compare SSI rates after class II (clean contaminated) colorectal surgery between patients who received C + M and those who received A/CA. We employed multivariable logistic regression to adjust for potential confounders, along with propensity score matching to adjust for group imbalance. RESULTS: From 2009 to 2018, 27,922 patients from 127 hospitals were included. SSI was diagnosed in 3132 (11.2%): 278/1835 (15.1%) in those who received A/CA and 2854/26,087 (10.9%) in those who received C + M (p < 0.001). The crude OR for SSI in the A/CA group as compared to C + M was 1.45 [CI 95% 1.21-1.75]. The adjusted OR was 1.49 [1.24-1.78]. This finding persisted in a 1:1 propensity score matched cohort of 1835 patients pairs with an OR of 1.60 [1.28-2.00]. Other factors independently associated with SSI were an ASA score > 2, a longer duration of operation, and a reoperation for a non-infectious complication. Protective factors were female sex, older age, antibiotic prophylaxis received 60 to 30 min before surgery, elective operation, and endoscopic approach. CONCLUSIONS: Despite its activity against enterococci, A/CA was less effective than C + M for preventing SSI, suggesting that it should not be a first choice antibiotic prophylaxis for colorectal surgery.

Treatment Failure and Adverse Events After Amoxicillin-Clavulanate vs Amoxicillin for Pediatric Acute Sinusitis.

Importance: Acute sinusitis is one of the most common indications for antibiotic prescribing in children, with an estimated 4.9 million such prescriptions in the US annually. Consensus does not exist regarding the optimal empirical antibiotic. Objective: To compare amoxicillin-clavulanate vs amoxicillin for the treatment of acute sinusitis in outpatient children. Design, Setting, and Participants: Cohort study of children and adolescents aged 17 years or younger with a new outpatient diagnosis of acute sinusitis and a same-day new prescription dispensation of amoxicillin-clavulanate or amoxicillin in a nationwide health care utilization database. Propensity score matching was used to mitigate confounding. Exposure: A new prescription dispensation of amoxicillin-clavulanate or amoxicillin. Main Outcomes and Measures: Treatment failure, defined as an aggregate of a new antibiotic dispensation, emergency department or inpatient encounter for acute sinusitis, or inpatient encounter for a sinusitis complication, was assessed 1 to 14 days after cohort enrollment. Adverse events were evaluated, including gastrointestinal symptoms, hypersensitivity and skin reactions, acute kidney injury, and secondary infections. Results: The cohort included 320 141 patients. After propensity score matching, there were 198 942 patients (99 471 patients per group), including 100 340 (50.4%) who were female, 101 726 (51.1%) adolescents aged 12 to 17 years, 52 149 (26.2%) children aged 6 to 11 years, and 45 067 (22.7%) children aged 0 to 5 years. Treatment failure occurred in 1.7% overall; 0.01% had serious failure (an emergency department or inpatient encounter). There was no difference in the risk of treatment failure between the amoxicillin-clavulanate and amoxicillin groups (relative risk [RR], 0.98 [95% CI, 0.92-1.05]). The risk of gastrointestinal symptoms (RR, 1.15 [95% CI, 1.05-1.25]) and yeast infections (RR, 1.33 [95% CI, 1.16-1.54]) was higher with amoxicillin-clavulanate. After patients were stratified by age, the risk of treatment failure after amoxicillin-clavulanate was an RR of 0.98 (95% CI, 0.86-1.12) for ages 0 to 5 years; RR was 1.06 (95% CI, 0.92-1.21) for 6 to 11 years; and RR was 0.87 (95% CI, 0.79-0.95) for 12 to 17 years. The age-stratified risk of adverse events after amoxicillin-clavulanate was an RR of 1.23 (95% CI, 1.10-1.37) for ages 0 to 5 years; RR was 1.19 (95% CI, 1.04-1.35) for 6 to 11 years; and RR was 1.04 (95% CI, 0.95-1.14) for 12 to 17 years. Conclusions and Relevance: In children with acute sinusitis who were treated as outpatients, there was no difference in the risk of treatment failure between those who received amoxicillin-clavulanate compared with amoxicillin, but amoxicillin-clavulanate was associated with a higher risk of gastrointestinal symptoms and yeast infections. These findings may help inform decisions for empirical antibiotic selection in acute sinusitis.

Association between perioperative prophylaxis with cefuroxime plus metronidazole or amoxicillin/clavulanic acid and surgical site infections in paediatric uncomplicated appendectomy: a Swiss retrospective cohort study.

OBJECTIVE: We aimed to evaluate the association between post-appendectomy SSI rates and the two most commonly used regimens for perioperative antimicrobial prophylaxis in Swiss children. METHODS: We conducted a retrospective cohort study, analysing data from the Swiss national SSI surveillance database with a study period from 2014 to 2018. All hospitals undertaking paediatric appendectomies in Switzerland participate in the surveillance. We compared the cumulative incidence and odds of post-appendectomy SSI within 30 days of surgery in children ≤ 16 years of age undergoing appendectomy for uncomplicated appendicitis and receiving perioperative antimicrobial prophylaxis with cefuroxime plus metronidazole or with amoxicillin/clavulanic acid using multivariable adjusted logistic regression and propensity-score matching. RESULTS: A total of 6207 cases were recorded in the study time frame. Overall SSI cumulative incidence was 1.9% (n = 119). 4256 children (54.9% male, median (IQR) age 12 [10, 14] years) received either cefuroxime plus metronidazole (n = 2348, 53.8% male) or amoxicillin/clavulanic acid (n = 1491, 57.0% male). SSI cumulative incidence was 1.1% (25/2348) among children receiving cefuroxime plus metronidazole and 2.8% (42/1491, p < 0.001) when receiving amoxicillin/clavulanic acid. The administration of cefuroxime plus metronidazole was associated with statistically significantly lower SSI odds compared to amoxicillin/clavulanic acid (aOR 0.35, 95%CI [0.20, 0.61], p < 0.001), and this was confirmed upon propensity-score matching. CONCLUSION: We found lower odds of post-appendectomy SSI in children receiving cefuroxime plus metronidazole compared to amoxicillin/clavulanic acid. Treating amoxicillin/clavulanic acid as the baseline, only 55 children need to receive cefuroxime plus metronidazole perioperative prophylaxis to avert one SSI. Existing guidelines recommending amoxicillin/clavulanic acid may need to be revised. Trial registration ISRCTN47727811, registered retrospectively.

Antibiotic treatment failure of uncomplicated urinary tract infections in primary care.

BACKGROUND: Higher resistance rates of > 20% have been noted in Enterobacteriaceae urinary isolates towards ciprofloxacin and co-trimoxazole (C + C) in Singapore, compared with amoxicillin-clavulanate and nitrofurantoin (AC + N). This study examined if treatment failure varied between different antibiotics, given different resistant rates, for uncomplicated urinary tract infections (UTIs) managed in primary care. We also aimed to identify gaps for improvement in diagnosis, investigations, and management. METHODS: A retrospective cohort study was conducted from 2019 to 2021 on female patients aged 18-50 with uncomplicated UTIs at 6 primary care clinics in Singapore. ORENUC classification was used to exclude complicated UTIs. Patients with uncomplicated UTIs empirically treated with amoxicillin-clavulanate, nitrofurantoin, ciprofloxacin or co-trimoxazole were followed-up for 28 days. Treatment failure was defined as re-attendance for symptoms and antibiotic re-prescription, or hospitalisation for UTI complications. After 2:1 propensity score matching in each group, modified Poisson regression and Cox proportional hazard regression accounting for matched data were used to determine risk and time to treatment failure. RESULTS: 3194 of 4253 (75.1%) UTIs seen were uncomplicated, of which only 26% were diagnosed clinically. Urine cultures were conducted for 1094 (34.3%) uncomplicated UTIs, of which only 410 (37.5%) had bacterial growth. The most common organism found to cause uncomplicated UTIs was Escherichia coli (64.6%), with 92.6% and 99.4% of isolates sensitive to amoxicillin-clavulanate and nitrofurantoin respectively. Treatment failure occurred in 146 patients (4.57%). Among 1894 patients treated with AC + N matched to 947 patients treated with C + C, patients treated with C + C were 50% more likely to fail treatment (RR 1.49, 95% CI 1.10-2.01), with significantly higher risk of experiencing shorter time to failure (HR 1.61, 95% CI 1.12-2.33), compared to patients treated with AC + N. CONCLUSION: Treatment failure rate was lower for antibiotics with lower reported resistance rates (AC + N). We recommend treating uncomplicated UTIs in Singapore with amoxicillin-clavulanate or nitrofurantoin, based on current local antibiograms. Diagnosis, investigations and management of UTIs remained sub-optimal. Future studies should be based on updating antibiograms, highlighting its importance in guideline development.

Efficacy of antimicrobials or placebo compared to amoxicillin-clavulanate in children with acute otitis media: a systematic review.

BACKGROUND: Acute otitis media (AOM) is the inflammation of the middle ear. It constitutes one of the most frequent infections which affects children and usually occurs between 6 to 24 months of age. AOM can emerge due to viruses and/or bacteria. The aim of the current systematic review is to assess in children between 6 months and 12 years of age with AOM, the efficacy of any antimicrobial agent or placebo compared with amoxicillinclavulanate, to measure the resolution of AOM or symptoms. METHODS: The medical databases PubMed (MEDLINE) and Web of Science were used. Data extraction and analysis were performed by two independent reviewers. Eligibility criteria were set, and only randomised control trials (RCTs) were included. Critical appraisal of the eligible studies was performed. Pooled analysis was conducted using the Review Manager v. 5.4.1 software (RevMan). RESULTS: Twelve RCTs were totally included. Three (25.0%) RCTs studied the impact of azithromycin, two (16.7%) investigated the impact of cefdinir, two (16.7%) investigated placebo, three (25.0%) studied quinolones, one (8.3%) investigated cefaclor and one (8.3%) studied penicillin V, compared to amoxicillin-clavulanate. In five (41.7%) RCTs, amoxicillin-clavulanate proved to be superior to azithromycin, cefdinir, placebo, cefaclor and penicillin V, while in seven (58.3%) RCTs its efficacy was comparable with other antimicrobials or placebo. The rates of AOM relapse after treatment with amoxicillin-clavulanate were comparable to those of other antimicrobials or placebo. However, amoxicillin-clavulanate was more effective in eradicating Streptococcus pneumoniae from the culture, when compared to cefdinir. The results of the meta-analysis were not evaluated due to substantial heterogeneity between studies. CONCLUSIONS: Amoxicillin-clavulanate should be the treatment of choice for children between 6 months and 12 years of age with AOM.