The benzalkonium chloride resistant or sensitive phenotype of Listeria monocytogenes planktonic cells did not dictate the susceptibility of its biofilm counterparts

The main goal of this work was to approach food industry conditions in the comparison of the susceptibility of biofilms of Listeria monocytogenes to the biocides benzalkonium chloride (BAC) and peracetic acid (PAA). Twelve isolates of L. monocytogenes, including nine well characterized BAC resistant strains were used. Biofilms were produced on stainless steel coupons (SSC), at 11 °C (refrigeration temperature) or at 25 °C (room temperature), in culture media simulating clean (nutrient limiting) or soiled (nutrient rich) growth conditions. Neither different nutrient availability nor growth temperature showed significant effect (p > .05) on biofilm formation. PAA confirmed to be more effective than BAC in biofilm elimination. Biofilms formed under nutritional stress tended to differentiate more the response to BAC of the resistant or sensitive strains, but the resistant or sensitive phenotype of the planktonic cells did not dictate biofilm susceptibility.

Correlation of genotypes and route of transmission with histologic activity and disease stage in chronic hepatitis C.

Our objective was to evaluate the histopathological features of chronic hepatitis C of 64 liver biopsies and to correlate this with the route of transmission of hepatitis C virus, the genotype of HCV, and the patient's age. Moderate chronic hepatitis was the most frequently observed (62.5%). Cirrhosis was observed in 14 patients (21.9%) and was more frequently found among patients over 40 years of age (34.3% vs. 6.9%, P = 0.025). The mean histopathological activity index (HAI) was significantly higher in the sporadic (10+/-3.1) than the posttransfusional (7.5+/-3.7) and the intravenous drug use (IVDU) groups (6.3+/-2.8) (P<0.02). Moreover the sporadic group showed more fibrosis (P<0.04) than the posttransfusional group. No liver cirrhosis was found in the IVDU group. The overall prevalence of HCV variants was: 54.7% type 1b, 4.6% type 1a, 37.5% type 2c, 1.6% type 2b, 1.6% type 2. The genotype distribution showed no relation to the HAI, hepatitis activity (grade), and fibrosis (stage) of the liver disease. In conclusion, the sporadic route of transmission of HCV was related to a more severe chronic hepatic disease, a finding that could influence future antiviral therapies. The predominance of HCV type 1b in this study reflects the higher frequency of this variant in our area. Our data suggests that the ultimate consequence of HCV chronic infection depends on patient age rather than on HCV genotype.

Idiopathic hypereosinophilic syndrome presenting as cholestatic liver disease.

We report the case of a 34-year-old white man with recurrent episodes of abdominal pain, cholestasis and eosinophilia. The diagnosis of idiopathic hypereosinophilic syndrome (IHS) was made after exclusion of all known causes of eosinophilia. Liver biopsy revealed an eosinophilic infiltrate with biliary damage. The patient recovered after prednisolone treatment. We review the literature on the association between IHS and liver disease.