Decubitus ulcer infection and bacteremia due to tazobactam/piperacillin-resistant Veillonella parvula.

This is the first case report of decubitus infection and bacteremia due to Veillonella parvula (V. parvula). A patient in his 70s with pre-existing diabetes mellitus was admitted with decubitus infection, and tazobactam/piperacillin treatment was initiated. Tazobactam/piperacillin-resistant V. parvula was detected in the blood and decubitus site cultures. The antimicrobial treatment was changed to clindamycin and cefmetazole. Antimicrobial therapy was administered for 28 days. The patient was transferred to a convalescent hospital. V. parvula occasionally causes infection in immunocompromised patients with underlying diseases, such as diabetes. An appropriate evaluation by culture test is important for diagnosis, treatment, and recurrence prevention. Tazobactam/piperacillin is often used in the treatment of multi-bacterial infections such as decubitus infections. V. parvula may be resistant to tazobactam/piperacillin, and this possibility should be taken into account when administering treatment.

Antibiotic Prophylaxis in Patients Undergoing Lung Transplant: Single-Center Cohort Study.

Perioperative antibiotic prophylaxis (PAP) in lung transplant recipients (LuTRs) has high heterogeneity between centers. Our aim was to investigate retrospectively the approach to PAP in our center over a 20-year period (2002-2023), and its impact on early post-operative infections (EPOIs) after lung transplantation (LuT). Primary endpoint was diagnosis of EPOI, defined as any bacterial infection including donor-derived events diagnosed within 30 days from LuT. Main exposure variables were type of PAP (combination vs. monotherapy) and PAP duration. We enrolled 111 LuTRs. PAP consisted of single-agent or combination regimens in 26 (25.2%) and 85 (74.8%) LuTR. Median PAP duration was 10 days (IQR 6-13) days. Piperacillin/tazobactam was the most common agent used either as monotherapy (n = 21, 80.7%) or as combination with levofloxacin (n = 79, 92.9%). EPOIs were diagnosed in 30 (27%) patients. At multivariable analysis no advantages were found for combination regimens compared to single-agent PAP in preventing EPOI (OR: 1.57, 95% CI: 0.488-5.068, p:0.448). The impact of PAP duration on EPOIs development was investigated including duration of PAP ≤6 days as main exposure variables, without finding a significantly impact (OR:2.165, 95% CI: 0.596-7.863, p: 0.240). Our results suggest no advantages for combination regimens PAP in preventing EPOI in LuTR.

Optimizing Piperacillin Dosing in Pediatric Liver Transplant Recipients: A Case Series.

BACKGROUND: Pathophysiological changes post-liver transplantation impact the pharmacokinetics and pharmacodynamics of antibiotics. Piperacillin, often used in combination with tazobactam, is a key antibiotic after transplantation to its broad-spectrum activity, but there is a lack of specific pharmacokinetic data in this population. This study aims to describe the pharmacokinetic parameters and target attainment of piperacillin in pediatric liver transplant recipients. METHODS: Patients with preserved renal function (estimated glomerular filtration rate > 50 mL/min/1.73 m2) receiving intravenous piperacillin-tazobactam at 112.5 mg/kg every 8 h (100 mg piperacillin/12.5 mg tazobactam), with a rapid infusion (0.5-1 h), were included. Two blood samples per child were collected during the same interval within 48 h of starting therapy. A Bayesian approach was applied to estimate individual pharmacokinetic parameters and perform dosing recommendations against Enterococcus spp., Enterobacterales and Pseudomonas aeruginosa. RESULTS: Eight patients with median age of 8 months were included. Median piperacillin clearance and central volume of distribution for the cohort were 11.11 L/h/70 kg and 9.80 L/70 kg, respectively. Seven patients (87.5%) presented with concentrations below the target of 100% fT > MIC. Simulations suggested that these patients required more frequent dosing and extended duration of infusion to ensure target attainment. One patient (12.5%) had trough concentrations that exceed 16 mg/L and could receive a lower daily dose. CONCLUSIONS: This case series highlights the importance of personalized therapy in pediatric liver transplant recipients due to the unpredictable and highly variable piperacillin pharmacokinetics in this population.

Aspiration Pneumonia Leading to Clostridium ramosum Bacteremia in a Neutropenic Patient: Case Report and Management Strategy.

BACKGROUND Clostridium ramosum is an anaerobic, spore-producing, gram-positive rod, enteric pathogen that is difficult to identify and is rarely pathogenic. We present a case of Clostridium ramosum bacteremia secondary to aspiration pneumonia in a 65-year-old immunocompromised man on chemotherapy for follicular lymphoma. CASE REPORT We report the case of a 65-year-old man, on active chemotherapy for follicular lymphoma, presenting with a fever of 38.3°C, nonproductive cough, fatigue, and confusion. Physical examination was unremarkable except for +2 lower-extremity pitting edema. CT abdomen pelvis showed left lower-lung consolidation and CT chest angiogram showed that the consolidation was concerning for infarct verses abscess and segmental/subsegmental pulmonary emboli despite anticoagulation use. Blood cultures later grew Clostridium ramosum, which was successfully treated with IV piperacillin-tazobactam. Subsequent outpatient imaging demonstrated resolution of the lung consolidation. CONCLUSIONS Our case highlights the rare diagnosis of Clostridium ramosum bacteremia secondary to aspiration pneumonia in an immunocompromised patient and our approach to management. We highlight the difficulties in identification of Clostridium ramosum, rare pathogenicity, risk factors, and potential sources.

Need for a targeted perioperative antibiotic treatment protocol for patients with preoperative biliary drainage undergoing pancreaticoduodenectomy.

PURPOSE: To evaluate the bacterobilia in patients undergoing pancreaticoduodenectomy (PD) based on whether they carry a preoperative biliary drainage or not and to analyse if a targeted perioperative antibiotic treatment based on the expected microbiology leads in no differences in Surgical Site Infections (SSI) between the groups. METHODS: Retrospective observational single-center study of patients undergoing pancreaticoduodenectomy with preoperative biliary stent (group P, Prosthesis) and without stent (group NP, No Prosthesis). Postoperative complications including SSI and its subtypes were analyzed after applying a targeted perioperative antibiotic treatment protocol with cefotaxime and metronidazole (group NP) and piperacillin-tazobactam (group P). RESULTS: Between January 2014 and December 2021, 127 patients were treated (84 in group NP and 43 in group P). Intraoperative cultures were positive in 16.7% (group NP) vs 76.7% (group P, p < 0.01). Microorganisms isolated in group NP included Enterobacterales (10.7%) and Enterococcus spp. (7.1%) with no Candida detected. In group P: Enterobacterales (51.2%), Enterococcus spp. (48.8%), and Candida (16.3%) were higher (p < 0.01%). No differences in morbidity and mortality were observed between the groups. SSI rate was 17.8% in group NP and 23.2% in group P (ns). CONCLUSION: Bacterobilia differs in patients with biliary drainage, showing a higher presence of Enterobacterales, Enterococcus spp., and Candida. There were no differences in SSI incidence after applying perioperative antibiotic treatment tailored to the expected microorganisms in each group. This raises the need to reconsider conventional surgical prophylaxis in patients with biliary stent.

Are Antibiotics of Value for a Whipple Procedure?

Pancreatoduodenectomy is a complex surgical procedure with a high rate of morbidity, of which surgical-site infections (SSIs) make a large portion. Reduction of SSI rates is critical to decrease hospital lengths of stay, readmissions, delays in adjuvant therapies, and financial health care burden. Current clinical guidelines recommend the administration of cefoxitin as surgical prophylaxis prior to pancreatoduodenectomy. In April 2023, a randomized controlled trial was published in JAMA which showed that piperacillin-tazobactam as perioperative surgical prophylaxis prior to pancreatoduodenectomy decreased 30 day SSI rates (primary outcome), clinically relevant postoperative pancreatic fistula, postoperative sepsis, and Clostridium difficile infection rates.

The role of piperacillin/tazobactam in the treatment of Hidradenitis suppurativa.

Background: Hidradenitis suppurativa (HS) is a chronic inflammatory skin disease. Most patients with moderate-to-severe disease require long-term antibiotic treatment, or biologic treatments to control their disease. Despite these interventions, relapses are common. This study evaluated the effectiveness of piperacillin/tazobactam treatment in patients with Hurley stage II and III HS who experienced disease flares and did not respond to conventional antibiotic and biologic treatment. Methods: Patients with HS hospitalized at the Department of Dermatology, Sheba Medical Center between August 2021 and January 2023 were retrospectively analyzed. Results: A cohort of ten such patients were treated with piperacillin/tazobactam for 6-21 days. Eight (80%) and two (20%) patients respectively demonstrated 2- and 1-grade improvements, from their baseline HS-Physician Global Assessment score. During the follow-up period, nine patients were monitored. HS Clinical Response (HiSCR) was achieved in six (66.7%) and five (55.6%) patients at the 3- and 6-month follow-up visits, respectively. Conclusions: In conclusion, Piperacillin/tazobactam emerges as a promising therapeutic option for disease flare-up in patients with Hurley stage II and III HS who do not respond to conventional treatment. Thus, piperacillin/tazobactam should be considered as crisis therapy for this patient subset.

A NSQIP-Based Randomized Clinical Trial Evaluating Choice of Prophylactic Antibiotics for Pancreaticoduodenectomy.

Surgical site infection is a common complication following pancreaticoduodenectomy and is a major source of postoperative morbidity. Surgical site infection is more common among patients who undergo preoperative biliary instrumentation, likely because of the introduction of intestinal flora into the normally sterile biliary tree. Frequently, bacterial isolates from surgical site infections after pancreaticoduodenectomy demonstrate resistance to the antibiotic agents typically used for surgical prophylaxis, suggesting that broad-spectrum coverage may be beneficial. This chapter summarizes the current evidence regarding surgical site infection following pancreatic surgery and describes the rationale and methodology underlying a multicenter randomized trial evaluating piperacillin-tazobactam compared with cefoxitin for surgical site infection prevention following pancreaticoduodenectomy. As the first U.S. randomized surgical trial to utilize a clinical registry for data collection, this study serves as proof of concept for registry-based clinical trials. The trial has successfully completed patient accrual, and study results are forthcoming.

Risk of Clostridioides difficile infection following different antibiotics: insights from multi-source medical data.

OBJECTIVE: Antibiotic utilization stands as the strongest modifiable determinant for Clostridioides difficile infection (CDI). However, previous studies have relied on aggregated antibiotic categories, leaving prescribers without detailed comparative risk information for individual antibiotics. The objective of this study was to estimate the risk of CDI comprehensively across specific antibiotics. METHODS: Two methodologies were integrated to access and rank the risk of CDI associated with individual antibiotics or classes. Initially, a network comparison was conducted by analysing data from randomized controlled trials (RCTs). Subsequently, a real-world disproportionality analysis using the Food and Drug Adverse Event Reporting System (FAERS) database complemented and enriched the findings from RCTs. RESULTS: The network comparison, encompassing 61 RCTs with 25,931 patients, revealed that exposure to cefepime [odds ratio (OR) 2.56, 95% confidence interval (CI) 1.20-5.44; P=0.02] and imipenem/cilastatin (OR 3.86, 95% CI 1.61-9.29; P=0.003) exhibited higher frequencies of CDI compared with piperacillin/tazobactam. No significant differences were observed between the carbapenems, albeit a trend indicating higher incidence of CDI with imipenem/cilastatin compared with meropenem (OR 3.89, 95% CI 0.94-16.09). In the FAERS disproportionality analysis, nearly all antibiotics displayed associations with CDI, and CDI risk signals often clustered within the majority of antibiotic classes. Among these, lincomycin demonstrated the strongest association (OR 112.17, 95% CI 51.68-243.43). Additionally, oral third-generation cephalosporins tended to exhibit higher CDI risk signals than other antibiotics. CONCLUSIONS: The findings unveiled substantial diversity in the risk of CDI, both within and between antibiotic classes, providing valuable guidance for clinicians in antibiotic prescription decisions and for initiatives aimed at antibiotic stewardship.

Clinical manifestations and treatment outcomes for patients with Pseudomonas endocarditis.

OBJECTIVES: To investigate clinical outcomes of patients with Pseudomonas endocarditis and identify factors associated with treatment failure. METHODS: Adult patients meeting definitive Duke's criteria for Pseudomonas endocarditis at 11 hospitals were identified between May 2000 and February 2024. Failure was defined as death or microbiological failure by day 42. First-line therapy consisted of cefepime, piperacillin/tazobactam, ceftazidime or ceftolozane/tazobactam alone or in combination. RESULTS: Forty-eight patients met inclusion criteria; 29% were persons who inject drugs and 13% were organ transplant recipients. Pseudomonas aeruginosa was the causative species in 98% of cases. Patients who experienced 42 day cure were more likely to be initially managed with first-line ß-lactam agents compared with those who experienced clinical failure (97% versus 62%, P = 0.004). Treatment with first-line ß-lactams was associated with shorter time to treatment initiation and a lower likelihood of infection due to MDR Pseudomonas spp. In the univariate model, patients who experienced 90 day mortality were more likely to have prosthetic valve endocarditis (57% versus 24%, P = 0.02), an intracardiac complication (36% versus 9%, P = 0.04) and a higher median (IQR) Pitt bacteraemia score [2.5 (2-3.8) versus 1 (0-2), P = 0.048]. Combination therapy did not improve clinical outcomes but did increase the rate of adverse effects resulting in drug discontinuation compared with monotherapy, (21% versus 0%, P = 0.08). CONCLUSIONS: This is the largest study of Pseudomonas endocarditis to date. We identified improved clinical outcomes when cefepime, piperacillin/tazobactam, ceftazidime or ceftolozane/tazobactam were used for initial treatment. We did not identify a clinical benefit for combination treatment.

Surgical prophylaxis in pancreatoduodenectomy: Is cephalosporin still the drug of choice in patients with biliary stents in situ?

BACKGROUND: Universal surgical prophylaxis for pancreatoduodenectomy (PD) is practiced, with cephalosporins recommended in most guidelines. Recent studies suggest piperacillin-tazobactam (PTZ) prophylaxis in biliary-stented patients is superior in preventing surgical site infections (SSIs). This study aims to refine surgical prophylaxis recommendations based on the local microbial profile and evaluate the clinical outcomes of biliary-stented compared with non-stented patients. METHODS: This was a retrospective study of all consecutive PD patients at Singapore General Hospital between January 2013 to December 2019. The primary outcome was post-operative SSI rates. Secondary outcomes included rates of ceftriaxone-resistant Klebsiella pneumoniae, Escherichia coli, and Enterococcus species from intraoperative bile cultures and 30-day mortality. RESULTS: There were 130 biliary-stented and 211 non-stented patients included. Majority of biliary-stented patients received ceftriaxone ± metronidazole prophylaxis (83/130, 63.8 %) while 30/130 (23.8 %) received PTZ. Most non-stented patients received ceftriaxone ± metronidazole prophylaxis (163/211, 77.3 %). Between biliary-stented and non-stented patients, post-operative SSIs (40.8 % vs 38.4 %, p = 0.662), and 30-day mortality rates (1.5 % vs 1.4 %, p = 1.000) were comparable. The adjusted odds of post-operative SSIs was significantly lower in biliary-stented patients prescribed PTZ as compared to non-PTZ prophylaxis (0.29, 95 % CI (0.10-0.79), p = 0.015). Ceftriaxone-resistant Klebsiella spp. and/or Escherichia coli (27.6 % vs 3.8 %, p < 0.001) as well as Enterococcus species (46.1 % vs 11.5 %, p < 0.001), were more prevalent in intraoperative bile cultures of biliary-stented patients, while frequencies in non-stented patients were low. CONCLUSION: PTZ prophylaxis effectively reduced SSIs in stented patients post-pancreatoduodenectomy. Based on the local microbial profile, ceftriaxone prophylaxis may be used for prophylaxis in non-stented patients.

Chloramphenicol treatment revisited - demographics, clinical characteristics, and outcomes of hospitalized patients.

Limited literature exists on chloramphenicol's clinical use. In this retrospective, single-center case-series, we examined 183 chloramphenicol-treated and 81 piperacillin-tazobactam-treated medical patients. Chloramphenicol recipients were older, more debilitated, cognitively impaired, and penicillin allergic, while increased need for inotropics, higher leukocyte count, and higher creatinine levels were notable in the piperacillin-tazobactam group. Pneumonia was the most common indication, with no mortality difference between groups. While acknowledging its antimicrobial activity and potential benefit in specific conditions such as pneumonia, further clinical studies are needed to assess the role of chloramphenicol in the setting where other alternatives are available.

Preventing Pneumonia in High-risk Patients After Esophageal Cancer Surgery: Mini-tracheostomy and Tazobactam/Piperacillin.

BACKGROUND/AIM: We evaluated the usefulness of prophylactic mini-tracheostomy (PMT) and perioperative administration of tazobactam/piperacillin (TAZ/PIPC) in high-risk patients after esophagectomy. PATIENTS AND METHODS: We retrospectively studied 89 consecutive high-risk patients who underwent esophagectomy for esophageal cancer between January 2013 and December 2021. We defined patients with two or more of the following factors as high risk: age ≥70 years, performance status ≥1, respiratory dysfunction, liver dysfunction, cardiac dysfunction, renal dysfunction, diabetes mellitus, albumin <3.5 g/dl, and Brinkman index >600. Standard management was administered to the first 50 patients (standard group). PMT and TAZ/PIPC were administered to the next 39 patients (combination group). Patient characteristics and short-term outcomes were compared before and after propensity-score matching. RESULTS: Before propensity-score matching, 24-hour urine creatinine clearance, retrosternal route, 3-field lymph node dissection, and open abdominal approach were more common, postoperative pneumonia (13% vs. 36%, p=0.045) and complications of grade ≥3b (2.6% vs. 22%, p=0.01) were less frequent, and the postoperative hospital stay was shorter (median: 23 vs. 28 days, p=0.022) in the combination group than in the standard group. In propensity-score matching, patient characteristics, except for 24-h creatinine clearance and reconstructive route, were matched for 23 paired patients. Postoperative pneumonia (8.7% vs. 39%, p=0.035) and complications of grade ≥3b (0% vs. 26%, p=0.022) were less frequent and postoperative hospital stay was shorter (median: 22 vs. 25 days, p=0.021) in the combination group than in the standard group. CONCLUSION: PMT with TAZ/PIPC can potentially prevent postoperative pneumonia in high-risk patients after esophagectomy.

Piperacillin/tazobactam-induced sudden severe thrombocytopenia in a patient with a pressure ulcer: a case report.

The standard treatment for an infected pressure ulcer (PU) with osteomyelitis is debridement, wound coverage and antibiotic administration. However, systemic administration of antibiotics in patients with osteomyelitis is controversial, and the optimal treatment duration for chronic osteomyelitis has not been standardised. We report a case of sudden severe thrombocytopenia induced by piperacillin/tazobactam (PIPC/TAZ) in a patient with PU-related osteomyelitis. A 57-year-old male patient with paraplegia, using a wheelchair full-time, presented to our plastic surgery department with infection of a stage IV hard-to-heal ischial PU. We surgically debrided the necrotising tissue and raised an ipsilateral biceps femoris musculocutaneous propeller flap for wound coverage. Polymicrobial infections, including Pseudomonas aeruginosa, were detected in the bone biopsy sample; therefore, systemic PIPC/TAZ was administered for the osteomyelitis. Unexpectedly, during the next 12 days of antibiotic administration, the patient's platelet count acutely dropped to 1×103/µl over three days. Based on a series of examinations, PIPC/TAZ was suspected to be the most likely cause of the severe thrombocytopenia. After drug discontinuation, the thrombocytopenia gradually improved. PIPC/TAZ is one of the most widely used antibiotic combinations in the plastic surgery field; it is conventionally administered for hard-to-heal wounds such as PUs and diabetic foot. The present case suggests that surgeons must take special precautions for patients undergoing PIPC/TAZ treatment. In this report, PIPC/TAZ-induced thrombocytopenia and the efficacy of antibiotic treatment for PU-related osteomyelitis are discussed in light of the available literature.

Postdiscontinuation Antibiotic Exposure in Hospitalized Infants at Risk for Late-onset Sepsis in the Neonatal Intensive Care Unit.

BACKGROUND: In the neonatal intensive care unit, infants are at risk for late-onset sepsis. When blood cultures are negative, antibiotic stewardship efforts encourage stopping antibiotics, yet the duration of therapeutic exposure after the last dose is unknown. METHODS: This retrospective cohort study of simulated antibiotic exposures used published population pharmacokinetic models within drug-specific neonatal intensive care unit cohorts of preterm and term infants, postnatal age 7-60 days and exposed to cefepime, piperacillin-tazobactam or tobramycin. Monte Carlo simulations (NONMEM 7.3) were used to predict steady-state exposures after a 72-hour antibiotic course per Neofax dosing. Exposure was assessed relative to drug-specific minimum inhibitory concentration (MIC) targets between 1 and 16 mcg/mL for Pseudomonas and Enterobacteriaceae species. Postdiscontinuation antibiotic exposure (PDAE) was defined as the time from the last dose to when antibiotic concentration decreased below a specific MIC. RESULTS: Piperacillin-tazobactam, cefepime and tobramycin cohorts included infants with median gestation age 29, 32 and 32 weeks and postnatal age 17, 19 and 15 days, respectively. The mean PDAE was 19-68 hours, depending on the specific antibiotic/MIC combination. PDAE was longer for infants <28 days old and preterm (vs. term) infants. Cefepime exhibited the longest mean PDAE of 68 hours for Enterobacteriaceae MIC 1. Piperacillin mean PDAE was 25 hours for Enterobacteriaceae MIC 8. Tobramycin had a short mean PDAE of 19 hours. CONCLUSIONS: Piperacillin and cefepime exposures remained therapeutic long after the expected 8- to 12-hour dosing interval. PDAE is an important consideration for antibiotic stewardship among hospitalized infants, particularly premature infants and those within 1 month postbirth.