Optimal Duration Of Antimicrobial Therapy Research Articles

Short-Course Versus Prolonged-Course Antimicrobial Therapy in Adults With Catheter-Related Septic Thrombosis: A Propensity-Weighted Retrospective Study

Abstract Background Optimal duration of antimicrobial therapy (AT) for catheter-related septic deep venous thrombosis (DVT) is unknown. We aimed to compare the outcomes of patients receiving short-course AT (≤21 days) versus prolonged-course AT (>21 days). Methods This was a monocentric retrospective study comparing adults with catheter-related septic DVT from 2015 to 2020 treated with short- or prolonged-course AT. A propensity score–weighted analysis was used to mitigate potential bias. The primary outcome was a composite of all-cause mortality or recurrent bloodstream infection 30 days after AT discontinuation. Results Of 172 patients with catheter-related septic DVT, 104 were treated with prolonged-course AT and 68 with short-course AT. In the propensity score analysis, we found no significant difference in 30-day all-cause mortality or relapse between the 2 groups (inverse probability of treatment weighted hazard ratio [wHR], 2.16 [95% confidence interval {CI}, .68–6.88]; P = .192). No differences in 90-day all-cause mortality and 90-day relapse were observed between the treatment groups (wHR, 1.01 [95% CI, .49–2.05], P = .987 and 1.13 [95% CI, .08–15.62], P = .928, respectively). Conclusions A 21-day AT could be an effective and safe option to treat catheter-related septic DVT. Further randomized studies are needed to establish the optimal duration of AT for patients with catheter-related septic DVT.

1815. Assessment of Therapy Duration for Non-Staphylococcal Gram-Positive Bloodstream Infections

Abstract Background The optimal duration of antimicrobial therapy for non-staphylococcal Gram-positive (GP) bloodstream infections (BSIs) remains unknown. The purpose of this study was to evaluate clinical outcomes in patients with short (6-10 days) vs. long (11-21 days) duration of therapy (DOT) for non-staphylococcal GP BSIs. Methods Adult patients with BSI due to Streptococcus or Enterococcus spp. admitted to a community health system from January 2016 to December 2021 were included in this retrospective chart review. Patients were excluded for polymicrobial BSI, positive culture deemed contamination, infectious source requiring prolonged treatment, DOT < 6 or > 21 days, or transfer, hospice, or death prior to therapy completion. The primary endpoint was 90-day all-cause mortality. Descriptive statistics, chi-square or Fisher’s exact test, and the student t-test were used for data analysis. Results Of 3,544 patients identified, 384 were screened and 86 included. There were 71 patients in the long DOT group and 15 patients in the short DOT group. All included patients were on active therapy for the entire DOT. Baseline characteristics were similar except patients in the long DOT group were more likely to have an infectious diseases consultation and a non-pulmonary source of infection (Table 1). All-cause mortality at 90 days was similar between short vs. long DOT groups (0% vs. 3%, p=0.51) (Table 2). The secondary endpoints of 30-day all-cause mortality, 30-day and 90-day BSI recurrence due to the same organism, 30-day readmission, and hospital length of stay were not statistically different between groups (Table 2). The most common pathogen identified in the short DOT group was Streptococcus pneumoniae (n=8), and the most common identified pathogens identified in the long DOT group was Streptococcus agalactiae (n=22), Enterococcus faecalis (n=14), and S. pneumoniae (n=13) (Table 3). Conclusion In this retrospective review of non-staphylococcal GP BSIs, there was no statistical difference in clinical outcomes between the short and long DOT arms. Additional research is needed to identify the optimal duration of antimicrobial therapy for non-staphylococcal GP BSIs. Disclosures All Authors: No reported disclosures.

Duration of antimicrobial therapy after video-assisted thoracoscopic surgery for thoracic empyema and complicated parapneumonic effusion: A single-center study

BackgroundThere are no evidence-based reports on the proper duration of antimicrobial therapy following video-assisted thoracoscopic surgery debridement (VATS-D) in thoracic empyema (TE) or complicated parapneumonic effusion (PPE). This study aimed to investigate the optimal duration of antimicrobial therapy after VATS-D. MethodsBetween January 2011 and December 2019, 33 patients corresponding to American College of Chest Physicians (ACCP) category 3 or 4 undergoing VATS-D were included. The times until the body temperature (BT) was confirmed to be less than 37.5 °C and 37.0 °C, white blood cell count (WBC) less than 10,000/μl, segmented neutrophils (seg) less than 80%, and C-reactive protein (CRP) level less than 25% of the preoperative value were retrospectively analyzed. ResultsThe median time from the onset of TE/PPE to surgery was 13 days. The median durations of preoperative and postoperative antibiotic use were five and seven days, respectively. Major complications occurred in four cases (three and one cases of respiratory failure and cerebral infarction, respectively). The median postoperative hospital stay was 14 days. Recurrence or progression to chronic empyema was seen in four cases. The median numbers of days until the conditions were met were three days for BT < 37.5 °C, six days for BT < 37.0 °C, four days for WBC<10,000, seven days for seg<80% and seven days for CRP<25%. ConclusionsThe proper duration of antimicrobial therapy after VATS-D for TE/PPE is approximately three to seven days. Urgent VATS-D may shorten the total antibiotic usage.

Shorter versus longer durations of antibiotic treatment for patients with community-acquired pneumonia: a protocol for a systematic review and meta-analysis

IntroductionCommunity-acquired pneumonia (CAP), frequently encountered in both outpatient and inpatient settings, is the leading cause of infectious disease-related mortality. While equipoise regarding the optimal duration of antimicrobial therapy to treat...

Pyogenic and Non-pyogenic Spinal Infections: Diagnosis and Treatment.

Spinal Infection (SI) is an infection of vertebral bodies, intervening disc, and/or adjoining para-spinal tissue. It represents less than 10% of all skeletal infections. There are numerous factors that predispose to developing a SI. Due to the low specificity of signs, delayed diagnosis is common. Hence, SI may be associated with poor outcomes. Diagnosis of SI must be supported by clinicopathological and radiological findings. MRI is a reliable modality of choice. Treatment options vary according to the site of the infection, disease progression, neurology, presence of instability, and general condition of the subject. Conservative treatment (orthosis/ bed-rest + antibiotics) is recommended during the early course with no/ lesser degree of neurological involvement and to medically unfit patients. Nevertheless, when conservative measures alone fail, surgical interventions must be considered. The use of concomitant antimicrobial drugs intravenously during initial duration followed by oral administration is a necessity. Controversies exist regarding the optimal duration of antimicrobial therapy, yet never given less than six weeks. Heterogeneity in clinical picture and associated co-morbidities with a range of treatment modalities are available; however, a common applicable guideline for SI does not exist. Managing SI must be tailored on a case-to-case basis.

61. Short- versus prolonged-courses of antimicrobial therapy for patients with uncomplicated Pseudomonas aeruginosa bloodstream infection

BackgroundThe optimal duration of antimicrobial therapy for uncomplicated Pseudomonas aeruginosa bloodstream infection (BSI) is unknown. We compared the outcomes of short and prolonged courses of antimicrobial therapy in adults with uncomplicated pseudomonal BSI.MethodsAll patients with uncomplicated P. aeruginosa BSI admitted at a tertiary-care hospital from May 2016 to September 2020 were included. We compared the rate of recurrent P. aeruginosa infection and 30-day mortality among patients who underwent short (7‒11 days) and prolonged (12‒21 days) courses of antimicrobial therapy using propensity score analysis with the inverse probability of treatment weighting (IPTW) method. ResultsWe evaluated 1,477 patients with uncomplicated P. aeruginosa BSI; of them, 290 met the eligibility criteria, including 97 (33%) who underwent short-course therapy (9 [interquartile range (IQR), 8‒11] days) and 193 (67%) who underwent prolonged-course therapy (15 [IQR, 14‒18] days). We found no significant difference in the risk of recurrence or 30-day mortality between the prolonged-course and short-course groups (n=10, 11% vs. n=32, 16%; IPTW-adjusted hazard ratio (HR) 0.61; 95% confidence interval (CI) 0.30−1.24; p=0.17). The recurrence of P. aeruginosa infection at any site within 180 days of completing therapy occurred significantly more in the prolonged-course group (n=10, 10% vs. n=38, 20%; IPTW-adjusted HR 0.48; 95% CI 0.24−0.96, p=0.04). The resistance acquisition in subsequent P. aeruginosa isolates was more frequent in the prolonged-course group, although the difference was not statistically significant (n=2, 20% vs. n=12, 32%; p=0.70). ConclusionShort-course antimicrobial therapy could be as effective as prolonged-course therapy for uncomplicated P. aeruginosa bloodstream infection.Disclosures All Authors: No reported disclosures

111. Duration of Antibiotic Therapy after Debridement and Implant Retention in Patients with Periprosthetic Joint Infections

BackgroundDebridement, antibiotics, and implant retention (DAIR) is appropriate for select acute postoperative and hematogenous periprosthetic joint infections (PJIs). However, the optimal duration of antimicrobial therapy in patients treated with DAIR has not been defined. Therefore, we aimed to identify the ideal duration of parenteral and oral antibiotics after DAIR. MethodsWe performed a retrospective study of patients >18 years of age with hip or knee PJI managed with DAIR between January 1, 2008, and December 31, 2018, at Mayo Clinic. PJI was defined using criteria adapted from the International Consensus Meeting on PJI. The outcome was defined as either PJI recurrence or unplanned reoperation due to infection. Joint-stratified Cox proportional hazards regression models with time-dependent covariates were used to assess nonlinear effects of antibiotic duration. Hazard ratios were computed based on prespecified time points for comparison, whereas p-values represented the overall effect across the entire range of durations.ResultsThere were 247 unique episodes of PJI in 237 patients during the study period. Parenteral antibiotics were given in 99.2% of cases (n=245). This was followed by chronic oral antibiotic suppression in 92.2% (n=226) with a median duration of 2.2 years (1.0-4.1).DAIR failed in 65 cases over a median follow-up of 4.4 years, with a 5-year cumulative incidence of 28.1%. After adjustment for risk factors, there was no significant association between duration of parenteral antibiotics and treatment failure (p=0.203), with no difference between four versus six weeks (HR 1.11; 95% CI 0.71-1.75) (Figure 1). However, both use and longer duration of oral antibiotic therapy was associated with a lower risk of failure (p=0.006). To account for the possibility that this association was driven by results during early follow-up, conditional analyses at one- and two-year follow-up were performed. Both showed a significantly lower risk for a longer duration of antibiotics (Figure 2). Figure 1. Time-Dependent Analysis of Parenteral Antibiotic Duration Figure 2. Time-Dependent Analysis of Oral Antibiotic Suppression Duration ConclusionAfter DAIR, efficacy from four weeks of parenteral antibiotics was no different from six weeks when followed by chronic oral antibiotic suppression. Our results could not establish an optimal duration but suggested that continuing suppression portends a lower risk of failure of DAIR. Disclosures Elie Berbari, MD, Uptodate.com (Other Financial or Material Support, Honorary unrelated to this work) Matthew P. Abdel, MD, Stryker and AAOS Board of Directors (Board Member, Other Financial or Material Support, Royalties) Aaron J. Tande, MD, UpToDate.com (Other Financial or Material Support, Honoraria for medical writing)

Short versus prolonged courses of antimicrobial therapy for patients with uncomplicated Pseudomonas aeruginosa bloodstream infection: a retrospective study.

The optimal duration of antimicrobial therapy for uncomplicated Pseudomonas aeruginosa bloodstream infection (BSI) is unknown. We compared the outcomes of short and prolonged courses of antimicrobial therapy in adults with uncomplicated pseudomonal BSI. All patients with uncomplicated P. aeruginosa BSI admitted at a tertiary-care hospital from April 2010 to April 2020 were included. We compared the primary outcome (a composite of the rate of recurrent P. aeruginosa infection and mortality within 30 days after discontinuing antimicrobial therapy) among patients who underwent short (7‒11 days) and prolonged (12‒21 days) courses of antimicrobial therapy using propensity score analysis with the inverse probability of treatment weighting (IPTW) method. We evaluated 1477 patients with P. aeruginosa BSI; of them, 290 met the eligibility criteria who received antimicrobial agents with in vitro activity, including 97 (33%) who underwent short-course therapy [median of 9 (IQR = 8‒11) days] and 193 (67%) who underwent prolonged-course therapy [median of 15 (IQR = 14‒18) days]. We found no significant difference in the risk of recurrence or 30 day mortality between the prolonged-course and short-course groups [n = 30 (16%) versus n = 11 (11%); IPTW-adjusted HR = 0.68, 95% CI = 0.34 - 1.36, P = 0.28]. The prolonged-course therapy did not significantly reduce the risk of the recurrence of P. aeruginosa infection within 180 days compared with short-course therapy [n = 37 (19%) versus n = 12 (12%); IPTW-adjusted HR = 0.57, 95% CI = 0.29 - 1.10, P = 0.09]. Short-course antimicrobial therapy could be as effective as prolonged-course therapy for uncomplicated P. aeruginosa BSI.

How Antibiotics Stewardship Can Be Safely Implemented in Patients with Septic Shock?

In critically ill patients with sepsis and septic shock, the need for prompt and adequate antibiotic therapy is balanced by the risk of excessive antibiotic exposure that leads to emergence of multidrug-resistant pathogens. As such, antibiotic stewardship programs propose a set of operating rules from antibiotic treatment initiation to de-escalation and finally cessation. In this review, we will describe the rationale for early antibiotic treatment in septic patients, how to optimize initial antibiotic treatment, rules for early treatment discontinuation in pathogen-negative sepsis, and optimal duration of antimicrobial therapy.

Science, Medicine, and the Anesthesiologist

Science, Medicine, and the Anesthesiologist

The optimal duration of antimicrobial therapy for lower respiratory tract infection in patients with neuromuscular disorders based on a clone library analysis of the bacterial 16S rRNA gene sequence

ObjectivesThe aim of this study is to determine the optimal duration of antimicrobial therapy for lower respiratory tract infection (LRTI) in neuromuscular disorder (NMD) patients. MethodsThis prospective study included 13 episodes from 9 NMD patients hospitalized for bacterial LRTI. Sputum samples were collected from these patients during the three consecutive days after their admission. Bacterial cell counts and the proportion of the most predominant bacterium identified by a clone library analysis of the bacterial 16S rRNA gene sequence in the samples obtained before antimicrobial therapy were serially investigated. ResultsAll episodes were initially treated with ampicillin/sulbactam. In 12 episodes with a therapeutic effect, the bacterial cell counts in the samples obtained on the third day of therapy were significantly lower than those before therapy (P = 0.0013). In most of these episodes, the most predominant bacterium in the sample obtained before therapy was undetectable by the third day of therapy. In the one patient without a therapeutic effect, neither the bacterial cell counts nor the proportion of the most predominant bacterium in the sample obtained before therapy decrease after therapy. ConclusionShort-term antimicrobial therapy is sufficiently effective for LRTI in NMD patients if the initial therapy is effective.

Shortening antibiotic duration in the treatment of acute cholangitis: rationale and study protocol for an open-label randomized controlled trial

BackgroundAntimicrobial therapy with appropriate biliary drainage is considered the standard of care for acute cholangitis, but the optimal duration of antimicrobial therapy remains unknown. Seven to 10 days of antimicrobial therapy are common for the treatment of acute cholangitis, but a recent retrospective cohort study suggested a shorter duration might be effective. A shorter duration of antimicrobial therapy can be beneficial in decreasing the length of hospital stay, improving patients’ quality of life, decreasing adverse effects, and even contributing to a decrease in the occurrence of antimicrobial resistance.Methods/designWe will conduct a multi-centre, open-label, randomized, non-inferiority trial to compare short-course therapy (SCT) with conventional long-course therapy (LCT) in treating patients with acute cholangitis. SCT consists of 5-day intravenous antimicrobial therapy if the patients had clinical improvement, while at least 7 days of intravenous antibiotics will be provided to the LCT group. The primary outcome is clinical cure at 30 days after onset. Patients will be randomly assigned in an open-label fashion. A total sample size of 150 was estimated to provide a power of 80% with a one-sided α level of 2.5% and a non-inferiority margin of 10%.DiscussionThis trial is expected to reveal whether SCT is non-inferior to conventional LCT or not, and may provide evidence that one can shorten the treatment duration for acute cholangitis for the benefit of patients.Trial registrationUniversity Hospital Medical Information Network, UMIN000028382. Registered on 30 August 2017.

Efficacy and safety of intermittent maintenance therapy after successful treatment of Mycobacterium avium complex lung disease.

The optimal duration of antimicrobial therapy for Mycobacterium avium complex lung disease (MAC-LD) is unknown, and recurrence rates are high after treatment discontinuation. Intermittent therapy is recommended for the initial treatment of non-cavitary nodular/bronchiectatic MAC-LD. We hypothesized that intermittent maintenance therapy (IMT) could effectively prevent recurrence after successful treatment of MAC-LD. Adult patients diagnosed with MAC-LD who received IMT after successful daily therapy (DT) between January 1, 2006 and December 31, 2016 were identified from clinical databases at three institutions in Japan. Treatment outcomes were evaluated for all patients. Of 38 patients (median age, 66 years; 29 women; nodular/bronchiectatic form, 29 patients) who received IMT after successful treatment, one was excluded due to death from an unknown cause, 1 month after IMT initiation. Finally, treatment outcomes were evaluated for 37 patients. Twenty-eight (76%) patients had sustained negative culture results over a median follow-up duration of 2.7 (interquartile range [IQR], 1.9-6.0) years, while six (16%) required switching to DT because of clinical deterioration over a median follow-up duration of 2.7 (IQR, 1.6-4.1) years. Favorable clinical outcomes were achieved for all patients who exhibited clinical deterioration. All patients tolerated the antimicrobials without discontinuation, and follow-up drug susceptibility testing showed negative results for clarithromycin-resistant MAC in the patients who experienced clinical deterioration. IMT after successful treatment may be a feasible option for patients with MAC-LD. Further studies should determine the population that would benefit from this strategy.

Prosthetic Joint Infections: an Update.

Prosthetic joint infection (PJI) is a rare but serious complication that is frequently misdiagnosed. We aimed to highlight the nuances of PJI diagnosis and antimicrobial therapies and provide clarity in key areas of management. Current research in PJI centers on a potential role for diagnostic biomarkers, molecular techniques, and implant sonication to reduce culture-negativity rates. The optimal duration of antimicrobial therapy remains controversial. A high clinical index of suspicion for PJI combined with data from multiple preoperative and intraoperative tests enables timely diagnosis and treatment. Biomarkers, molecular methods, and implant sonication are currently adjunctive to traditional diagnostic techniques. Shorter courses of antimicrobial therapies as well as the role of chronic suppressive therapy need confirmation by randomized controlled trials. Existing practices for preoperative dental prophylaxis and treatment of asymptomatic bacteriuria warrant revision based on evidence arguing against risk for PJI.

Short-Course Antimicrobial Therapy Does Not Increase Treatment Failure Rate in Patients with Intra-Abdominal Infection Involving Fungal Organisms.

Fungi frequently are isolated in intra-abdominal infections (IAI). The Study to Optimize Peritoneal Infection Therapy (STOP-IT) recently suggested short-course treatment for patients with IAI. It remains unclear whether the presence of fungi in IAI affects the optimal duration of Antimicrobial therapy. We hypothesized that a shorter treatment course in IAI with fungal organisms would be associated with a higher rate of treatment failure. Patients enrolled in the STOP-IT trial were stratified according to the presence or absence of a fungal isolate. They were analyzed as a subgroup based on original randomization to either the control group or an experimental group that received a four-day course of Antimicrobial therapy and by comparison with those without a fungal component to their infection. Descriptive comparisons were performed using a χ2, Fisher exact, or Kruskal-Wallis test as appropriate. The primary outcome was a composite of recurrent IAI, surgical site infection, and death. A total of 411 patients in the study (79%) had available culture data, of which 58 (14%) had positive fungal cultures. The most common organisms were Candida albicans and C. glabrata. The treatment failure rate was equivalent in the experimental and control arms (29.6% vs. 22.6%; p = 0.54). Patients with fungal isolates were more likely to have malignant disease (25.9% vs. 9.6%; p = 0.0004) and coronary artery disease (22% vs. 12%; p = 0.04), but were otherwise similar to those without fungal isolates. Patients with fungal isolates had more hospital days (median 10 vs. 7; p < 0.0001) and more days to resumption of enteral intake (median 5 vs. 3; p = 0.0006), but there was no difference in the composite outcome. Patients with IAI involving fungal organisms randomized to a shorter course of Antimicrobial therapy had no difference in the rate of treatment failure. These results suggest that the presence of fungi in IAI may not indicate independently the need for a longer course of Antimicrobial therapy.

Evaluation of a Short Course of Antimicrobial Therapy for Complicated Intra-Abdominal Infections in Critically Ill Surgical Patients.

The optimal duration of antimicrobial therapy for treatment of complicated intra-abdominal infections (cIAI) in critically ill surgical patients is unknown. Recent evidence suggests that a short (four-day) course of therapy may be effective, however data in severely critically ill patients are limited. A single-center, retrospective, cohort study was conducted at a tertiary academic medical center. Adult patients admitted to the surgical intensive care unit (SICU) with cIAI between December 2011 and July 2015 were enrolled. Patients undergoing transplantation and those with less than 24 h in the SICU were excluded. Patients were divided into two groups, short (≤ 7 d) and long (> 7 d) antimicrobial therapy. The primary outcome was treatment failure, which was defined as a composite of recurrent cIAI, secondary extra-abdominal infection, and/or in-hospital mortality from any cause. Categorical and continuous data were analyzed with χ2 and Mann-Whitney U tests, respectively. Binary logistic regression was performed to determine factors associated with treatment failure and mortality. Of 1,679 patients screened, 240 were included, 103 in the short and 137 in the long group. Patients in the short and long groups received a median of 5 and 14 d of therapy, respectively (p < 0.001). Treatment failure occurred less frequently with a short duration of therapy (39% versus 63%, p < 0.001) and it occurred two days sooner after source control in patients receiving the shorter courses of antimicrobial therapy (short, median 6 d, interquartile range [IQR] 3-9; long, 8 d, IQR 6-14; p < 0.001). Logistic regression demonstrated that a long duration of therapy was associated with treatment failure (odds ratio [OR] 2.186, 95% confidence interval [CI] 1.251-3.820, p = 0.006), but not with mortality (OR 0.738, 95% CI 0.329-1.655, p = 0.461). In critically ill surgical patients with cIAI, a short duration of antimicrobial therapy after source control resulted in similar outcomes to previously published studies, providing support for the safety of this approach in critically ill patients.

Optimal duration of antimicrobial therapy for uncomplicated Gram-negative bloodstream infections.

Optimal antimicrobial treatment duration for Gram-negative bloodstream infection (BSI) remains unclear. This retrospective cohort study examined effectiveness of short (7-10days) and long (>10days) courses of antimicrobial therapy for uncomplicated Gram-negative BSI. Hospitalized adults with uncomplicated Gram-negative BSI at Palmetto Health hospitals in Columbia SC, USA from January 1, 2010 to December 31, 2013 were identified. Multivariate Cox proportional hazards regression with propensity score adjustment was used to examine risk of treatment failure in the two groups. During the study period, 117 and 294 patients received short and long courses of antimicrobial therapy for uncomplicated Gram-negative BSI, respectively. Overall, the median age was 67years, 258 (63%) were women, 282 (69%) had urinary source of infection, and 271 (66%) had BSI due to Escherichia coli. The median duration of antimicrobial therapy was 8.5 and 13.3days in the short and long treatment groups, respectively. After adjustment for the propensity to use a short course of therapy, risk of treatment failure was higher in patients receiving short compared to long courses of antimicrobial agents (HR 2.60, 95% CI: 1.20-5.53, p=0.02). Other risk factors for treatment failure included liver cirrhosis (HR 5.83, 95% CI: 1.89-15.02, p=0.004) and immune compromised status (HR 4.30, 95% CI: 1.57-10.80, p=0.006). Definitive antimicrobial therapy with intravenous or highly bioavailable oral agents was associated with reduced risk of treatment failure (HR 0.33, 95% CI: 0.14-0.73, p=0.006). The current results support common clinical practice of 2weeks of antimicrobial therapy for uncomplicated Gram-negative BSI.

Optimal Duration of Antimicrobial Therapy for Bloodstream Infections Due to Gram-Negative Bacilli

Optimal Duration of Antimicrobial Therapy for Bloodstream Infections Due to Gram-Negative Bacilli

Complicated Intra-Abdominal Infections: The Old Antimicrobials and the New Players.

Complicated intra-abdominal infections (cIAIs) are an important cause of morbidity and mortality worldwide. They are diagnosed when the initial abdominal organ infection has spread into the peritoneal space. Successful treatment relies on adequate source control and appropriate empiric antimicrobial therapy. Inappropriate antimicrobial therapy may result in poor patient outcomes and increases in healthcare costs. Current guidelines recommend several single and combination antimicrobial regimens; however, empiric antimicrobial treatment has been complicated by the increasing rates of resistant organisms, especially the extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae. Additionally, the overuse of carbapenems to combat these resistant pathogens has contributed to the rise of carbapenemase-producing microorganisms, especially Klebsiella pneumoniae. This increasing resistance has prompted the development of novel antimicrobials like ceftazidime-avibactam and ceftolozane-tazobactam, whose activity extends to ESBL-producing microorganisms. Furthermore, the optimal duration of antimicrobial therapy is still unknown, and further research is necessary to find a definitive answer. This review will focus on antimicrobial therapies recommended by the current guidelines, the individual properties of these agents, appropriate duration of therapy, recent clinical trials, and place in therapy of the antimicrobial agents recently approved for the treatment of cIAIs.

Short-Course Therapy for Intra-Abdominal Infection

For complicated intra-abdominal infections, the optimal duration of antimicrobial therapy after achievement of source control remains unclear. Now, in