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Background: Acinetobacter pittii is a nosocomial pathogen rarely involved in community-acquired infections. We report for the first time that A. pittii can be responsible for cavitary community-acquired pneumonia and study its virulence, and discuss its pathogenesis and treatment options.Case Presentation: A 45-year-old woman with a history of smoking and systemic lupus was admitted to Nimes University Hospital (France) with coughing and sputum lasting for three weeks. Thoracic CT scanner showed cavitary pneumonia. Broncho-alveolar lavage cultures found community-acquired Acinetobacter calcoaceticus-baumannii complex. The clinical outcome was favourable after twenty-one days of antimicrobial treatment by piperacillin/tazobactam and amikacin then cefepime. Multilocus sequence typing (MLST) analyses identified an A. pittii ST249. Despite the atypical clinical presentation with an unexpected partial destruction of lung parenchyma, we found very low virulence potential of the A. pittii strain with nematode killing assays and biofilm formation test. The median time required to kill 50% of the nematodes was 7 ± 0.3 days for A. pittii ST249, 7 ± 0.2 days for A. baumanii NAB ST2 and 8 ± 0.2 days for E. coli OP50, (p > 0,05). A. pittii ST249 showed significantly slower biofilm formation than A. baumanii NAB ST2: BFI = 8.83 ± 0.59 vs 3.93 ± 0.27 at 2 h (p < 0.0001), BFI = 6.3 ± 0.17 vs 1.87 ± 0.12 at 3 h (p < 0.0001) and BFI = 3.67 ± 0.41 vs 1.7 ± 0.06 after 4 h of incubation (p < 0.01).Conclusions: Community-acquired A. pittii should be considered as possible cause of sub-acute cavitary pneumonia particularly in a smoking and/or immunocompromised patient despite its low virulence potential. [ABSTRACT FROM AUTHOR]

Background: Carbapenemase-producing Enterobacteriaceae (CPE) are difficult to identify among carbapenem non-susceptible Enterobacteriaceae (NSE). We designed phenotypic strategies giving priority to high sensitivity for screening putative CPE before further testing.Methods: Presence of carbapenemase-encoding genes in ertapenem NSE (MIC > 0.5 mg/l) consecutively isolated in 80 French laboratories between November 2011 and April 2012 was determined by the Check-MDR-CT103 array method. Using the Mueller-Hinton (MH) disk diffusion method, clinical diameter breakpoints of carbapenems other than ertapenem, piperazicillin+tazobactam, ticarcillin+clavulanate and cefepime as well as diameter cut-offs for these antibiotics and temocillin were evaluated alone or combined to determine their performances (sensitivity, specificity, positive and negative likelihood ratios) for identifying putative CPE among these ertapenem-NSE isolates. To increase the screening specificity, these antibiotics were also tested on cloxacillin-containing MH when carbapenem NSE isolates belonged to species producing chromosomal cephalosporinase (AmpC) but Escherichia coli.Results: Out of the 349 ertapenem NSE, 52 (14.9%) were CPE, including 39 producing OXA-48 group carbapenemase, eight KPC and five MBL. A screening strategy based on the following diameter cut offs, ticarcillin+clavulanate <15 mm, temocillin <15 mm, meropenem or imipenem <22 mm, and cefepime <26 mm, showed 100% sensitivity and 68.1% specificity with the better likelihood ratios combination. The specificity increased when a diameter cut-off <32 mm for imipenem (76.1%) or meropenem (78.8%) further tested on cloxacillin-containing MH was added to the previous strategy for AmpC-producing isolates.Conclusion: The proposed strategies that allowed for increasing the likelihood of CPE among ertapenem-NSE isolates should be considered as a surrogate for carbapenemase production before further CPE confirmatory testing. [ABSTRACT FROM AUTHOR]

Background: Ingestion of cranberry (Vaccinium macrocarpon Ait.) has traditionally been utilized for prevention of urinary tract infections. The proanthocyanidins (PACs) in cranberry, in particular the A-type linkages have been implicated as important inhibitors of primarily P-fimbriated E. coli adhesion to uroepithelial cells. Additional experiments were required to investigate the persistence in urine samples over a broader time period, to determine the most effective dose per day and to determine if the urinary anti-adhesion effect following cranberry is detected within volunteers of different origins. Methods: Two separate bioassays (a mannose-resistant hemagglutination assay and an original new human T24 epithelial cell-line assay) have assessed the ex-vivo urinary bacterial anti-adhesion activity on urines samples collected from 32 volunteers from Japan, Hungary, Spain and France in a randomized, double-blind versus placebo study. An in vivo Caenorhabditis elegans model was used to evaluate the influence of cranberry regimen on the virulence of E. coli strain. Results: The results indicated a significant bacterial anti-adhesion activity in urine samples collected from volunteers that consumed cranberry powder compared to placebo (p < 0.001). This inhibition was clearly dose-dependent, prolonged (until 24 h with 72 mg of PAC) and increasing with the amount of PAC equivalents consumed in each cranberry powder regimen. An in vivo Caenorhabditis elegans model showed that cranberry acted against bacterial virulence: E. coli strain presented a reduced ability to kill worms after a growth in urines samples of patients who took cranberry capsules. This effect is particularly important with the regimen of 72 mg of PAC. Conclusions: Administration of PAC-standardized cranberry powder at dosages containing 72 mg of PAC per day may offer some protection against bacterial adhesion and virulence in the urinary tract. This effect may offer a nyctohemeral protection. [ABSTRACT FROM AUTHOR]

Background: We describe a case of severe Guillain-Barre syndrome (GBS) associated with chronic active hepatitis C and mixed cryoglobulinemia (MC). To our knowledge, this association between GBS and hepatitis C virus (HCV) infection has been rarely reported.Case Presentation: A 56-year-old man developed symmetrical muscle weakness in all extremities, areflexia and sensorial disorder followed by acute respiratory failure associated with chronic active hepatitis C, which was confirmed by the presence of anti-HCV antibodies in the serum and persistence of HCV RNA viral load for more than 6 months. Chronic hepatitis C was further complicated by type 3 MC. Electromyography showed peripheral nerve injury (mainly in axon). A severe acute motor sensory axonal neuropathy (AMSAN) was diagnosed. After treatment with intravenous immunoglobulin and plasma exchange followed by antiviral therapy by direct-acting antiviral agent, patient showed progressive recovery and was transferred 3 months after his first admission to a rehabilitation center.Conclusions: Our case reported a severe GBS associated with HCV infection and MC. EMG classified for the first time the subtype of GBS (severe AMSAN) correlated with severe clinical form. HCV infection should be screened in high-risk patients to prevent silent progression of the chronic hepatitis C and its potentially severe extra-hepatic manifestations. [ABSTRACT FROM AUTHOR]