Bloodstream infection caused by KPC-producing Klebsiella pneumoniae resistant to ceftazidime/avibactam: epidemiology and genomic characterization.

OBJECTIVES: The aim of this study was to evaluate the incidence of ceftazidime/avibactam resistance among Klebsiella pneumoniae carbapenemase (KPC)-producing K. pneumoniae (KPC-Kp) strains isolated from patients with bloodstream infection. METHODS: We collected 120 carbapenemase producing Enterobacteriaceae (CPE) strains from unique patients hospitalized in two Italian hospitals between January 2018 to February 2019. Strains were phenotypically characterized for the type of carbapenemase production and susceptibility to ceftazidime/avibactam. Ceftazidime/avibactam-resistant strains were characterized by whole-genome sequencing. RESULTS: During the study period, we characterized 105 (87.5%) KPC producers among a total of 120 CPE strains. Ceftazidime/avibactam resistance was found in three KPC-Kp strains isolated from patients with no history of previous ceftazidime/avibactam-based treatment. Of note, two out of three ceftazidime-avibactam-resistant KPC-Kp were also resistant to meropenem/vaborbactam. Genomic characterization showed that a ceftazidime/avibactam-resistant KPC-Kp harboured a mixed population with D179Y mutated KPC-2, while the other two ceftazidime-avibactam-resistant KPC-Kp possessed non-functional ompK35-ompK37 and mutated ompK36 porins associated with higher copy number of blaKPC gene. CONCLUSIONS: Our results showed that incidence of ceftazidime/avibactam resistance emerged in KCP-Kp strains independently from previous antimicrobial exposure. Resistance to ceftazidime/avibactam was associated with mutations within the blaKPC gene or porin deficiency associated with higher blaKPC copy number and is also related to the meropenem/vaborbactam resistance.

Management of KPC-producing Klebsiella pneumoniae infections.

BACKGROUND: Klebsiella pneumoniae carbapenemase (KPC)-producing K. pneumoniae (KPC-KP) has become one of the most important contemporary pathogens, especially in endemic areas. AIMS: To provide practical suggestion for physicians dealing with the management of KPC-KP infections in critically ill patients, based on expert opinions. SOURCES: PubMed search for relevant publications related to the management of KPC-KP infections. CONTENTS: A panel of experts developed a list of 12 questions to be addressed. In view of the current lack of high-level evidence, they were asked to provide answers on the bases of their knowledge and experience in the field. The panel identified several key aspects to be addressed when dealing with KPC-KP in critically ill patients (preventing colonization in the patient, preventing infection in the colonized patient and colonization of his or her contacts, reducing mortality in the infected patient by rapidly diagnosing the causative agent and promptly adopting the best therapeutic strategy) and provided related suggestions that were based on the available observational literature and the experience of panel members. IMPLICATIONS: Diagnostic technologies could speed up the diagnosis of KPC-KP infections. Combination treatment should be preferred to monotherapy in cases of severe infections. For non-critically ill patients without severe infections, results from randomized clinical trials are needed for ultimately weighing benefits and costs of using combinations rather than monotherapy. Multifaceted infection control interventions are needed to decrease the rates of colonization and cross-transmission of KPC-KP.

Predictors of outcome in patients with severe sepsis or septic shock due to extended-spectrum ß-lactamase-producing Enterobacteriaceae.

PURPOSE: There are few data in the literature regarding sepsis or septic shock due to extended-spectrum ß-lactamases (ESBL)-producing Enterobacteriaceae (E). The aim of this study was to assess predictors of outcome in septic patients with bloodstream infection (BSI) caused by ESBL-E. METHODS: Patients with severe sepsis or septic shock and BSI due to ESBL-E were selected from the INCREMENT database. The primary endpoint of the study was the evaluation of predictors of outcome after 30 days from development of severe sepsis or septic shock due to ESBL-E infection. Three cohorts were created for analysis: global, empirical-therapy and targeted-therapy cohorts. RESULTS: 367 septic patients were analysed. Overall mortality was 43.9% at 30 days. Escherichia coli (62.4%) and Klebsiella pneumoniae (27.2%) were the most frequent isolates. ß-lactam/ß-lactamase inhibitor (BLBLI) combinations were the most empirically used drug (43.6%), followed by carbapenems (29.4%). Empirical therapy was active in vitro in 249 (67.8%) patients, and escalation of antibiotic therapy was reported in 287 (78.2%) patients. Cox regression analysis showed that age, Charlson Comorbidity Index, McCabe classification, Pitt bacteremia score, abdominal source of infection and escalation of antibiotic therapy were independently associated with 30-day mortality. No differences in survival were reported in patients treated with BLBLI combinations or carbapenems in empirical or definitive therapy. CONCLUSIONS: BSI due to ESBL-E in patients who developed severe sepsis or septic shock was associated with high 30-day mortality. Comorbidities, severity scores, source of infection and antibiotic therapy escalation were important determinants of unfavorable outcome.

Comparison of clinical and pathological staging and long-term results of liver transplantation for hepatocellular carcinoma in a single transplant center.

Liver transplantation (OLT) is a treatment for hepatocellular carcinoma (HCC) superimposed on cirrhosis provided that the disease meets defined criteria. The aim of the study was to evaluate our experience with respect to clinical and pathological staging and long-term results. From 1996 to 2005, 50 patients underwent OLT for HCC including 43 men (86%) and seven women (14%) of median age 57 years (range 37 to 67). All patients fulfilled the Milan criteria. The HCC diagnosis was based on preoperative imaging and alpha-fetoprotein levels; no tumor biopsy was performed. Upon histological examination of the resected specimens, we discovered 6 (12%) incidentalomas and 8 (16%) cases of no HCC. Finally we had 42 "true" HCC. Twenty-six patients (52%) have been downstaged and 10 (20%) upstaged by preoperative imaging; 15% were pT1, 45% were pT2, 27% pT3, and 13% pT4a. Twenty-six percent of cases exceeded the Milan criteria. One patient (pT4a) with microvascular invasion died of pulmonary metastases at 14 months after transplantation. No HCC recurrences within the liver have been encountered at a median follow-up of 20 months (range 0 to 80 months). Overall the estimated 1-, 3-, and 5-year survival rates were 83%, 77%, and 72%, respectively. One-, 3-, and 5-year estimated survival rates were 87%, 75%, and 75% for pT1, and pT2, and 75%, 67%, and 67% for pT3 and pT4a, respectively (P = .99). Based on our experience OLT for HCC has long-term results comparable to those without HCC despite the presence of a significant number of cases exceeding the Milan criteria upon pathological staging.

De novo malignancies after kidney and liver transplantations: experience on 582 consecutive cases.

De novo malignancies after transplantation are a growing problem of solid organ transplant recipients, due to longer survival follow-up under chronic immunosuppression. The aim of this study was to analyze a population of 582 consecutive kidney (n = 382) and liver (n = 202) transplant recipients, who survived at least 12 months after transplantation, at a single transplant center for the development of de novo cancers. The incidence of de novo malignancies was 7% after both renal and liver transplantation. The median elapsed time from transplant to the diagnosis of de novo malignancy was 45 months (range 3 to 220) months for kidney and 37 months (range 12 to 101 months) for liver transplants. Skin cancers were the most common within renal recipients, while gastroenteric cancers were more frequently encountered in liver transplants. Oropharyngeal and upper digestive tract tumors were always associated with a history of chronic alcohol consumption in liver recipients. Liver transplant recipients treated for acute rejection had a worse cancer prognosis than patients without rejection 1- and 2-year survivals 83% and 63% versus 36% and 17% (P = .026). The estimated 1- and 2-year survival rates for all types of de novo malignancies were 79% and 66%, including 64% and 51% for solid organ tumors versus 89% and 89% for skin cancers and posttransplant lymphoproliferative disorder (PTLD) (P = .17) in renal transplants and 70% and 42%, including 57% and 28% for solid organ tumors versus 85% and 64% for skin cancers and PTLD (P = .43) in liver transplants respectively.

Liver transplantation from old donors into HCV and non-HCV recipients.

BACKGROUND: Chronic liver failure due to HCV-related cirrhosis is the leading indication for liver transplantation in Western countries. Inferior long-term results have been reported for liver transplantation in HCV patients, especially when marginal donor livers are utilized. The aim of this study was to retrospectively analyze the outcome of liver transplantation from elderly donors in HCV versus non-HCV recipients. METHODS: One hundred seventy-nine patients receiving 204 liver transplantations were divided into four groups according to HCV positivity and donor age (> or <65 years). Long-term survivals were calculated by the Kaplan-Meier method. RESULTS: Grafts from donors of >65 years into HCV-positive patients displayed lower patient and graft survival rates than HCV-negative cases, although macrosteatosis was more frequent (55% vs 9%, P =.02) among organs used for non-HCV cases. Moreover, HCV-positive recipients transplanted with a donor aged >65 years had significantly lower patient and graft survival (40% vs 78% [P =.01] and 40% vs 68% [P =.06], respectively) than patients receiving a liver from a younger donor. CONCLUSIONS: Our retrospective analysis, although hampered by a small number of patients transplanted with an old liver, suggest that the results of liver transplantation with a donor graft >65 years of age into an HCV-positive recipient shows a worse outcome than those from younger donors. Older livers should be reserved for non-HCV cases.

[Listeria monocytogenes meningitis. Description of a clinically significant case]. / Meningite da listeria monocytogenes. Descrizione di un caso clinico significativo.

Meningitis caused by Listeria monocytogenes is a rare affection: it develops from close contagion as professional illness (veterinarians, butchers) or in newborns by infected mothers; in indirect way for ingestion of contaminated food in subjects at high risk: elderly, immunosuppressed patients, alcoholics, diabetics. Clinically it is not diversified from the other bacterial meningitises. In this paper we present a case of Listeria monocytogenes meningitis in an adult female, without a sure occasion of infection and in absence of the factors of typical risk.

Intestinal co-infection by Cyclospora sp. and Cryptosporidium parvum: first report in an AIDS patient.

Cyclospora is recently described new human pathogenic coccidian causing intermittent diarrhoeal enteritis which may persist for weeks or months in immunocompetent subjects, particularly travellers visiting some tropical areas and countries, such as Nepal, the Caribbean, Peru and Mexico. More rarely this enteric pathogen affects immunocompromised humans, namely HIV-infected people or AIDS patients, with some clinical pictures recognized in normal hosts. We describe the first case of Cyclospora sp. and Cryptosporidium parvum associated diarrhoeal enteritis in an adult AIDS patient.