A case of Robinsoniella peoriensis bacteremia during using piperacillin-tazobactam.

Infections caused by Robinsoniella peoriensis, particularly bacteremia, are rare, of which only six cases were reported R. peoriensis bloodstream infections. This case report describes an instance of R. peoriensis bacteremia arising while we treated the patient with piperacillin-tazobactam. We treated an 84-year-old female patient with peritoneal carcinoma and febrile neutropenia using piperacillin-tazobactam. The patient's fever subsided. However, she developed a fever again on the fourth day of treatment with piperacillin-tazobactam. Blood cultures taken at this time were positive for R. peoriensis. We substituted meropenem and vancomycin for piperacillin-tazobactam, after which the patient improved. We administered meropenem and vancomycin for 17 days. There is currently no appropriate established treatment for R. peoriensis. In this case, we isolated R. peoriensis from blood cultures using piperacillin-tazobactam, although it was susceptible to piperacillin-tazobactam in vitro. Therefore, monotherapy with penicillins, especially piperacillin-tazobactam, may not be sufficient for R. peoriensis infections, although it was susceptible in vitro. Carbapenem may be effective in the treatment of R. peoriensis bloodstream infections.

Antibiotic Prophylaxis with Piperacillin-Tazobactam Reduces Post-Operative Infectious Complication after Pancreatic Surgery: An Interventional, Non-Randomized Study.

Background: This study aimed to evaluate the effectiveness of piperacillin-tazobactam as antibiotic prophylaxis in patients affected by a peri-ampullary tumor submitted to pancreatic surgery. Methods: A prospective, non-randomized, non-blinded, interventional study was conducted from January 2015 to March 2018. Patients were screened pre-operatively for Enterobacteriaceae producing extended-spectrum beta-lactamases (ESBL-PE). During the baseline period (January 2015-October 2016), surgical prophylaxis was performed with ampicillin-sulbactam. In the intervention phase (November 2016-March 2018), patients received piperacillin-tazobactam. Statistical analysis was performed by univariable and multivariable analysis with logistic regression models. Results: Overall, 383 patients were included in the baseline period and 296 in the intervention period. The surveillance strategy identified 47 ESBL-PE carriers (14%) in the baseline phase and 29 (10%) in the intervention phase. In the baseline period, the patients had a higher rate of hospital-acquired infection (43% versus 33%; p = 0.004), superficial surgical site infection (SSI) (11% versus 2%; p < 0.001), and pneumonia (16% versus 9%; p = 0.006). After the logistic regression, the baseline group had an odds ratio to develop superficial SSI and pneumonia of 7.7 (95% confidence interval [CI] 3-20) and 1.8 (95% CI 1-3.3), respectively. The ESBL colonization increased the mortality rate significantly (8% versus 3%; p = 0.017). Conclusions: Adopting antibiotic prophylaxis based on piperacillin-tazobactam is associated with a reduction in post-operative SSI, particularly superficial-SSIs. Further randomized studies would be warranted to evaluate this antibiotic combination more extensively in preventive strategies.

Prospective Cohort Study of the Tolerability of Prosthetic Joint Infection Empirical Antimicrobial Therapy.

The empirical use of vancomycin in combination with a broad-spectrum beta-lactam is currently recommended after the initial surgery of prosthetic joint infection (PJI). However, the tolerability of such high-dose intravenous regimens is poorly known. Adult patients receiving an empirical antimicrobial therapy (EAT) for a PJI were enrolled in a prospective cohort study (2011 to 2016). EAT-related adverse events (AE) were described according to the common terminology criteria for AE (CTCAE), and their determinants were assessed by logistic regression and Kaplan-Meier curve analysis. The EAT of the 333 included patients (median age, 69.8 years; interquartile range [IQR], 59.3 to 79.1 years) mostly relies on vancomycin (n = 229, 68.8%), piperacillin-tazobactam (n = 131, 39.3%), and/or third-generation cephalosporins (n = 50, 15%). Forty-two patients (12.6%) experienced an EAT-related AE. Ten (20.4%) AE were severe (CTCAE grade ≥ 3). The use of vancomycin (odds ratio [OR], 6.9; 95% confidence interval [95%CI], 2.1 to 22.9), piperacillin-tazobactam (OR, 3.7; 95%CI, 1.8 to 7.2), or the combination of both (OR, 4.1; 95%CI, 2.1 to 8.2) were the only AE predictors. Acute kidney injury (AKI) was the most common AE (n = 25; 51.0% of AE) and was also associated with the use of the vancomycin and piperacillin-tazobactam combination (OR, 6.7; 95%CI, 2.6 to 17.3). A vancomycin plasma overexposure was noted in nine (37.5%) of the vancomycin-related AKIs only. Other vancomycin-based therapies were significantly less at risk for AE and AKI. The EAT of PJI is associated with an important rate of AE, linked with the use of the vancomycin and the piperacillin-tazobactam combination. These results corroborate recent findings suggesting a synergic toxicity of these drugs in comparison to vancomycin-cefepime, which remains to be evaluated in PJI. (This study has been registered at ClinicalTrials.gov under identifier NCT03010293.).

Ceftolozane/tazobactam sensitivity patterns in Pseudomonas aeruginosa isolates recovered from sputum of cystic fibrosis patients.

Ceftolozane/tazobactam is a combination intravenous antibiotic with potentially important activity against drug-resistant Gram-negative organisms. Ceftolozane/tazobactam's in vitro activity was evaluated in 30 samples collected from 23 adult cystic fibrosis patients with extended and pan-resistant Pseudomonas aeruginosa in 2015. Testing results demonstrated that 30% of the isolates were susceptible,13% were intermediate, and 57% were resistant. This suggests that ceftolozane/tazobactam may be a useful antibiotic in carefully selected, multidrug-resistant Pseudomonas isolates.

Campylobacter jejuni and Pseudomonas coinfection in the setting of ulcerative colitis.

A 66-year-old woman presented with 2 days of fever and severe diarrhoea. She has a history of ulcerative colitis (UC), well controlled with medication. She also has a history of Ehlers-Danlos syndrome, infective endocarditis following aortic valve replacement and pulmonary embolism. She had complained of passing stool with traces of blood about 30 times per day. Stool testing for Clostridium difficile, routine culture and microscopy was done. She was started on ceftriaxone. CT scan revealed thick-walled colon consistent with UC flare. Flexible sigmoidoscopy showed active continuous colitis extending from the rectum to the proximal descending colon. Campylobacter jejuni was isolated from the stool and blood cultures yielded Pseudomonas aeruginosa. The antibiotic was transitioned to intravenous piperacillin/tazobactam and azithromycin followed by 2 weeks of intravenous cefepime. Her diarrhoea was controlled, and she was discharged for follow-up in 2 months.

Liver abscess caused by Clostridium haemolyticum infection after transarterial chemoembolization for hepatocellular carcinoma: A case report.

RATIONALE: Liver abscesses caused by Clostridium species infection are extremely rare. PATIENT CONCERNS: The authors report the first case of a liver abscess due to Clostridium haemolyticum, which occurred after transarterial chemoembolization (TACE) for hepatocellular carcinoma, in a 76-year-old woman who presented with right upper quadrant pain and fever. DIAGNOSES: Computed tomography of the abdomen after the second TACE showed an air-filled abscess around a compact, lipiodolized lesion in the right hepatic lobe. Pus culture showed the growth of C haemolyticum. INTERVENTIONS: Broad-spectrum antibiotics, including piperacillin/tazobactam and metronidazole, were administered, and a percutaneous 10-French pigtail catheter for pus drainage and culture was inserted in the liver abscess. OUTCOMES: Despite administering intensive treatments, she presented with rapid deterioration in mental status, liver function, and infection markers. She was transferred to the local hospital for palliative conservative treatment. LESSONS: Clostridia infections, including those involving C haemolyticum, are extremely rare, but should be considered as one of the causative organisms of liver abscess formation after TACE because of its rapid and fatal clinical course.

Onset of Hemophagocytic Lymphohistiocytosis during Piperacillin-Tazobactam Therapy in Three Children with Acute Focal Bacterial Nephritis.

Hemophagoytic lymphohistiocytosis (HLH) is a rare life-threatening disorder caused by overactivation of the immune system, associated with infections, autoimmune disorders, and malignancies. The pathological hallmark of HLH is phagocytosis of blood cells and platelets by activated macrophages and histiocytes. In this report, we describe the onset of HLH in three children, aged 2, 5 and 7 years old, during the treatment of acute focal bacterial nephritis (AFBN) with an antibiotic, piperacillin-tazobactam (PIPC-TAZ). AFBN is acute localized bacterial infection of the kidney without abscess formation. PIPC-TAZ was chosen for the treatment of AFBN, because it not only has indications for complicated urinary tract infections, but also covers most of the causative bacteria of urinary tract infections, including ß-lactamase-producing Escherichia coli. The clinical courses of the three patients were similar, and they were treated with PIPC-TAZ and amikacin (AMK) for AFBN. Fever went down 2 to 5 days later, and AMK was discontinued by day 6. However, fever recurred on 13 to 15 days after introduction of PIPC-TAZ therapy, even though all of the patients had no signs of recurrence of AFBN. The clinical features and laboratory tests of two patients fulfilled the criteria of HLH, whereas the other patient had initiated therapy before fulfilling the criteria. Cessation of PIPC-TAZ combined with corticosteroid therapy improved clinical symptoms. HLH of our patients was probably induced by PIPC-TAZ, as judged by the timing of the onset of HLH and the positivity of the drug-lymphocyte stimulation test. In conclusion, prolonged antibiotic therapy with PIPC-TAZ could be a cause of HLH.

Simplification of first-line antibacterial regimen for complicated appendicitis in children is associated with better adherence to guidelines and reduced use of antibiotics.

Acute appendicitis in children requires early surgery and short-course antibiotics active against Enterobacteriaceae and anaerobes. Although an aminoglycoside-containing three-drug regimen has been used successfully for decades, simpler regimens with similar efficacy are increasingly used. This study evaluated the impact of a switch from the combination of cefotaxime, metronidazole and gentamicin (regimen 1) to piperacillin/tazobactam (regimen 2) as first-line regimen for complicated acute appendicitis in children. In total, 171 children were enrolled [median (IQR) age, 10 (6-13) years], treated with regimen 1 (n = 80) or regimen 2 (n = 91) following surgery for complicated acute appendicitis. The two groups were comparable except for surgical approach (through laparoscopy in 46% vs. 88% for regimens 1 and 2, respectively; P < 0.001). Post-operative complications and duration of hospital stay were similar. Deviations from antibacterial treatment protocol decreased from 36% (29/80) to 14% (13/91) (P < 0.001), with a dramatic reduction in antibacterial treatment duration from median (IQR) of 15 (12-16) days to 5 (5-8) days (P < 0.001). Post-operative intra-abdominal abscess developed in 32 children (18.7%). Female sex (OR = 2.76, 95% CI 1.18-6.48; P = 0.02) and sepsis/septic shock on admission (OR = 4.72, 95% CI 1.12-19.97; P = 0.035) were independently associated with post-operative intra-abdominal abscess, but not antibacterial regimen. This study shows that simplification of first-line antibacterial regimen for complicated appendicitis in children was associated with reduced protocol deviation, reduced duration of antibiotics, and similar outcomes (post-operative complications and duration of hospital stay).

Propionibacterium acnes and Staphylococcus epidermidis olecranon bursitis/osteomyelitis: a case involving surgical and antibiotic treatment.

This report describes a 63-year-old generally healthy male with septic olecranon bursitis caused by Propionibacterium acnes The patient sustained a small laceration after striking the posterior aspect of his left elbow on a metal railing when he was at a public swimming pool. We concluded that P. acnes was not initially detected because cultures were only kept for 5 days. Consequently, initial antibiotic treatment failed. P. acnes and Staphylococcus epidermidis grew in a subsequent tissue culture. The infection did not respond to intravenous vancomycin although soft-tissue debridements were done. This likely reflected the presence of olecranon osteomyelitis (seen on MRI scans) in addition to inadequate treatment with this antibiotic in the setting of a polymicrobial infection. Eventually, the infection was eradicated with multiple soft-tissue debridements in addition to the continuation of vancomycin with daily intravenous piperacillin/tazobactam that was added for the final 4 weeks of antibiotic treatment.

Ceftolozane-tazobactam therapy for multidrug-resistant Pseudomonas aeruginosa infections in patients with hematologic malignancies and hematopoietic-cell transplant recipients.

Multidrug-resistant (MDR) Pseudomonas aeruginosa infection causes significant mortality among patients with hematologic malignancies and hematopoietic-cell transplant recipients. Ceftolozane-tazobactam (C-T) is a novel therapeutic option for MDR-P. aeruginosa infections but clinical experience in these patients is limited. We report favorable clinical outcomes and lack of limiting toxicities using C-T monotherapy to treat invasive MDR-P. aeruginosa infections in these patient populations.

Role Of Conservative Management In Emphysematous Gastritis.

Emphysematous gastritis (EG) is a rare disease of the stomach that is caused by gas-forming bacteria, and it can be lethal. There have been <70 reported cases in the English literature of this disease which carries a mortality rate up to 60%. Early recognition and treatment through conservative management have been a popular and successful choice in today's medicine. Studies have shown that surgical intervention does not confer a statistical benefit on mortality in this condition. We present another case of EG in a 33-year-old woman who was successfully managed conservatively.

Empiric antibiotic protocols for cancer patients with neutropenia: a single-center study of treatment efficacy and mortality in patients with bacteremia.

BACKGROUND: There are several empiric antibiotic treatment options for febrile neutropenia, yet there is no universally-accepted initial protocol. We aimed to assess the performance of a protocol (piperacillin, gentamicin and cefazolin) introduced over 40 years ago and compare its coverage against bacteria isolated from blood of neutropenic patients with that of various commonly used antibiotic treatment protocols. METHODS: Adults with neutropenia admitted between 2003 and 2012 to the hemato-oncologic departments and in whom blood cultures were taken on admission were included. Appropriateness of several common antibiotic protocols was assessed based on the susceptibility of the blood isolates. Crude mortality rates were computed by the susceptibility of bacteria isolated from patients' blood to the actual treatment given. RESULTS: In total, 180 admissions of neutropenic patients (95 in patients who had fever above 38 °C) with positive blood cultures were analyzed. The actual antibiotic regimen prescribed was deemed appropriate in 82% of bacteremia episodes. The recommended institutional protocol was used in 62% of bacteremia episodes in neutropenic patients. This protocol would have been appropriate in 85% of all neutropenic bacteremia episodes and 89% of episodes in febrile neutropenia patients compared with piperacillin/tazobactam (79%, P = 0.13 and 76%, P = 0.002, respectively) and imipenem (93%, P = 0.004 and 92%, P = 0.74, respectively). Isolation of bacteria resistant to the actual antibiotic treatment given was associated with higher mortality at one week and at 30 days. CONCLUSION: Common current antibiotic regimens provide similar coverage among febrile neutropenic patients, whereas broad spectrum antibiotic combinations maximize coverage among neutropenic patients.

Case Report: Strongyloides stercoralis Hyperinfection in a Patient with Chronic Lymphocytic Leukemia.

Strongyloides stercoralis is an intestinal nematode that can cause disseminated infection in an immunocompromised host. It is most commonly acquired in developing countries. It was previously a common infection in many parts of the United States, particularly in the Appalachian region, but is rarely identified currently. Here, we describe a patient born and raised in Appalachia, with no history of travel outside the United States, who presented with chronic lymphocytic leukemia and S. stercoralis hyperinfection characterized by acute respiratory failure, altered mental status, and extended-spectrum-beta-lactamase Klebsiella pneumoniae bacteremia. Despite prompt identification of the parasite on sputum microscopy and initiation of therapy with oral ivermectin and meropenem, the patient subsequently died. This case highlights the continued possibility of S. stercoralis infection in patients from Appalachia.

The burden of neutropenic sepsis in patients with advanced non-small cell lung cancer treated with single-agent docetaxel: A retrospective study.

OBJECTIVES: To describe rates of confirmed and suspected neutropenic sepsis (NS) and associated hospital resource utilisation in patients with non-small cell lung cancer (NSCLC) treated with docetaxel monotherapy following relapse after ≥1 line of chemotherapy in routine UK clinical practice. MATERIALS AND METHODS: A multi-centre, retrospective, observational research study was conducted in seven centres across England and Wales. Adult patients with stage III/IV NSCLC initiated on docetaxel monotherapy between 2010 and 2016 in routine clinical practice (aged ≥18 years at initiation) following failure of first-line chemotherapy were eligible. Data were collected from hospital medical records between May 2016 and July 2016, on all episodes of confirmed or suspected NS related to docetaxel monotherapy, including patient characteristics. Episodes of confirmed NS were defined as documented absolute neutrophil count <1.0×109/L, plus temperature >38°C or other signs/symptoms of sepsis, otherwise episodes were classified as suspected NS. RESULTS: 121 patients were included (median age 65.5 years; 57.9% male; median 4.0 cycles of docetaxel; 19.8% treated with prophylactic granulocyte-colony stimulating factor). Episodes of confirmed or suspected NS were recorded in 21/121 (17.4%) patients (11 confirmed episodes in 11 [9.1%] patients and 11 suspected episodes in 10 [8.3%] patients). Resource utilisation data were available for 21/22 episodes; the mean length of stay for confirmed NS admissions (n=11) was 9.2 (SD: 9.2) days and for suspected NS admissions (n=10) was 4.7 (SD: 4.6) days. The most commonly prescribed treatment for NS was piperacillin/tazobactam therapy (46.5% of all documented treatments). The mean total costs of managing patients with confirmed NS (n=11) and suspected NS (n=9) were £3163 (SD: £2921) and £1790 (SD: £1585) per patient, respectively. CONCLUSION: Rates of confirmed NS in UK clinical practice were broadly similar to those reported in clinical trials; however, the burden of suspected NS, not routinely reported elsewhere, is also substantial.

Lemierre's syndrome variant of the gut.

Infectious suppurative thrombophlebitis of the portal venous system, referred to as pylephlebitis, is a rare complication of intra-abdominal inflammatory processes. Advances in diagnostics and antibiotics have improved survival, but mortality remains remarkably high even in the most recent literature. The majority of patients have concomitant bacteraemia on presentation most commonly with typical gastrointestinal (GI) organisms. On rare occasion, patients have culture positive Fusobacterium, which has recently been associated with occult GI and genitourinary malignancies. Here, we describe a patient presenting with pylephlebitis and Fusobacterium bacteraemia who responded well to medical therapy, review pertinent literature and discuss the benefits of screening endoscopy in this patient population.

Using Population Pharmacokinetic Modeling and Monte Carlo Simulations To Determine whether Standard Doses of Piperacillin in Piperacillin-Tazobactam Regimens Are Adequate for the Management of Febrile Neutropenia.

Changes in the pharmacokinetics of piperacillin in febrile neutropenic patients have been reported to result in suboptimal exposures. This study aimed to develop a population pharmacokinetic model for piperacillin and perform dosing simulation to describe optimal dosing regimens for hematological malignancy patients with febrile neutropenia. Concentration-time data were obtained from previous prospective observational pharmacokinetic and interventional therapeutic drug monitoring studies. Nonparametric population pharmacokinetic analysis and Monte Carlo dosing simulations were performed with the Pmetrics package for R. A two-compartment model, with between-subject variability for clearance (CL), adequately described the data from 37 patients (21 males, age of 59 ± 12 years [means ± standard deviations] and weight of 77 ± 16 kg). Parameter estimates were CL of 18.0 ± 4.8 liters/h, volume of distribution of the central compartment of 14.3 ± 7.3 liters, rate constant for piperacillin distribution from the central to peripheral compartment of 1.40 ± 1.35 h-1, and rate constant for piperacillin distribution from the peripheral to central compartment of 4.99 ± 7.81 h-1 High creatinine clearance (CLCR) was associated with reduced probability of target attainment (PTA). Extended and continuous infusion regimens achieved a high PTA of >90% for an unbound concentration of piperacillin remaining above the MIC (fT>MIC) of 50%. Only continuous regimens achieved >90% PTA for 100% fT>MIC when CLCR was high. The cumulative fraction of response (FTA, for fractional target attainment) was suboptimal (<85%) for conventional regimens for both empirical and directed therapy considering 50% and 100% fT>MIC FTA was maximized with prolonged infusions. Overall, changes in piperacillin pharmacokinetics and the consequences on therapeutic dosing requirements appear similar to those observed in intensive care patients. Guidelines should address the altered dosing needs of febrile neutropenic patients exhibiting high CLCR or with known/presumed infections from high-MIC bacteria.

Clinical characteristics and outcomes of Pseudomonas aeruginosa bacteremia in febrile neutropenic children and adolescents with the impact of antibiotic resistance: a retrospective study.

BACKGROUND: Although the proportion of Pseudomonas aeruginosa infections has reduced after the introduction of antibiotics with anti-pseudomonal effects, P. aeruginosa bacteremia still causes high mortality in immunocompromised patients. This study determined the clinical characteristics and outcomes of P. aeruginosa bacteremia and the antibiotic susceptibilities of strains isolated from febrile neutropenic patients. METHODS: Thirty-one febrile neutropenic children and adolescents with underlying hematologic/oncologic disorders diagnosed with P. aeruginosa bacteremia between 2011 and 2016 were enrolled in the study. Their medical records were retrospectively reviewed to evaluate the demographic and clinical characteristics. Antibiotic susceptibility rates of the isolated P. aeruginosa to eight antibiotic categories (anti-pseudomonal penicillin, anti-pseudomonal penicillin and ß-lactamase inhibitor combination, anti-pseudomonal cephalosporin, monobactam, carbapenem, aminoglycoside, fluoroquinolone, and colistin) were also determined. Among the investigated factors, risk factors for mortality and infections by a multidrug-resistance (MDR) strain were determined. RESULTS: Thirty-six episodes of P. aeruginosa bacteremia were identified. The mean age of the enrolled patients was 9.5 ± 5.4 years, and 26 (72.2%) episodes occurred in boys. Acute myeloid leukemia (41.7%) and acute lymphoblastic leukemia (33.3%) were the most common underlying disorders. The 30-day mortality was 38.9%, and 36.1% of the episodes were caused by MDR strains. The deceased patients were more likely to experience breakthrough infection (P = 0.036) and bacteremia (P = 0.005) due to MDR strains when compared with the patients who survived. The survived patients more likely received appropriate empirical antibiotic therapy (P = 0.024) and anti-pseudomonal ß-lactam and aminoglycoside combination therapy (P = 0.039) compared with the deceased patients. The antibiotic susceptibility rates of the isolated P. aeruginosa strains were as follows: piperacillin/tazobactam, 67.6%; meropenem, 72.2%; and amikacin, 100%. CONCLUSIONS: Mortality due to P. aeruginosa bacteremia remained at 38.9% in this study, and more than one-third of the isolated strains were MDR. In this context, empirical antibiotic combination therapy to expand the antibiotic spectrum may be a strategy to reduce mortality due to P. aeruginosa bacteremia in febrile neutropenic patients.

Bacteraemia and liver abscess due to Fusobacterium necrophorum.

Fusobacterium necrophorum is the oropharyngeal pathogen usually associated with Lemierre's syndrome, a pharyngeal infection which evolves to sepsis, septic emboli and thrombophlebitis of the adjacent neck vessels. It is an uncommon causative bacteria of a liver abscess, and an extensive workup should, therefore, be performed in order to rule out potential sources of the infection. This case report describes the workup that led to the diagnosis of a colorectal carcinoma, which was deemed to be the source of the Fusobacterium bacteraemia.

Exacerbation of bronchiectasis by Pseudomonas monteilii: a case report.

BACKGROUND: Pseudomonas spp are important opportunistic and nosocomial pathogens. One such species is Pseudomonas monteilii (P. monteilii). It has been described as an environmental contaminant and potential pathogen. We identified this organism as the causative agent of an exacerbation of bronchiectasis and an environmental contaminant in our hospital on two separate occasions. CASE PRESENTATION: P. monteilii was the cause of an exacerbation of bronchiectasis in a 30-year-old HIV negative male. Patient presented with cough with sputum production and exertional dyspnea. The isolate was recovered from a sputum sample in significant counts and definitively identified by Matrix-Assisted Laser Desorption/Ionisation- Time of Flight Mass Spectrometry (MALDI-TOF MS). He was treated with piperacillin-tazobactam and recovered clinically and microbiologically. Another two isolates of the organism were contaminants from the hospital environment. The three isolates were susceptible to all tested antibiotics. Typing by Random amplification of polymorphic DNA (RAPD) found no clonal relationship between them. CONCLUSIONS: Less common species of Pseudomonas need to be identified accurately. This organism is identified by commonly used phenotypic systems as P. putida which may have contributed to a lower reported prevalence. P. monteilii is a known environmental contaminant and must also be considered as a potential pathogen, particularly in patients with chronic lung disease.