Israel Medical Association Journal

Background: Although indwelling catheters are increasingly used in modern medicine, they can be a source of microbial contamination and hard-to-treat biofilms, which jeopardize patient lives. At times 70% ethanol is used as a catheter-lock solution due to its bactericidal properties. However, high concentrations of ethanol can result in adverse effects and in malfunction of the catheters.

Objective: To determine whether low concentrations of ethanol can prevent and treat biofilms of Pseudomonas aeruginosa.

Methods: Ethanol was tested at a concentration range of 0.625–80% against laboratory and clinical isolates of P. aeruginosa for various time periods (2–48 hours). The following parameters were evaluated following ethanol exposure: prevention of biofilm formation, reduction of biofilm metabolic activity, and inhibition of biofilm regrowth.

Results: Exposing P. aeruginosa to twofold ethanol gradients demonstrated a significant biofilm inhibition at concentrations as low as 2.5%. Treating pre-formed biofilms of P. aeruginosa with 20% ethanol for 4 hours caused a sharp decay in the metabolic activity of both the laboratory and clinical P. aeruginosa isolates. In addition, treating mature biofilms with 20% ethanol prevented the regrowth of bacteria encased within it.

Conclusions: Low ethanol concentrations (2.5%) can prevent in vitro biofilm formation of P. aeruginosa. Treatment of previously formed biofilms can be achieved using 20% ethanol, thereby keeping the catheters intact and avoiding complications that can result from high ethanol concentrations.

Background: Clinicians’ impression of adolescents' alcohol or drug involvement may underestimate substance-related pathology.

Objectives: To describe the characteristics of adolescents presenting to the pediatric emergency department due to substance abuse and to determine whether physicians can reliably identify these patients.

Methods: We conducted a prospective cohort study of all patients aged 12–18 years presenting to a pediatric emergency department between 1 January 2005 and 31 December 2006 for whom a urine drug screen or ethanol blood levels was ordered. According to departmental protocol urine drug screen and ethanol levels are taken for specific indications. Based on the history and clinical findings the pediatrician in the ED[1] assessed on a 5-point likelihood scale the possibility that the patients’ symptoms were related to substance abuse.

Results: Of the 139 patients in the study group 40 (30%) tested positive for ethanol or drugs of abuse. The median age was 16. Compared with patients who tested negative, there were more patients with decreased level of consciousness among patients who tested positive for ethanol or drugs (5% vs. 33% respectively, P < 0.001). The median physician estimate for the likelihood of substance abuse was 5 in patients who tested positive and 2 in patients who tested negative (P < 0.001). The likelihood of a positive drug/ethanol test was not affected by age or gender.
Conclusions: Since the likelihood of substance abuse is higher in patients presenting with a low level of consciousness, physicians may accurately assess the likelihood of substance abuse in these patients

Background: Despite advances in cancer therapy the treatment of liver tumors remains a challenge. Most patients are poor candidates for surgical resection; both chemotherapy and irradiation have a low success rate and neither is without complications. New minimally invasive techniques for ablation of unresectable tumors have gained attention as effective treatment alternatives. Among these are percutaneous ethanol injection and radiofrequency ablation; both are effective for primary liver tumors and RFA is also effective for hepatic metastases.

Objective: To report our experience with PEI and RFA in the treatment of hepatic lesions.

Methods: The study included 49 lesions in 27 patients: 23 primary lesions in 13 patients treated with PEI and 26 lesions (22 secondary and 4 primary) in 14 patients treated with RFA. PEI was performed on an outpatient basis in the ultrasound suite; RFA was done in hospitalized patients (9 in the ultrasound suite and 4 in the operating room). Patients were followed with triphasic spiral computerized tomography 1 month after treatment and every 3±6 months thereafter.

Results: Complete necrosis was achieved with PEI on the first attempt in 11 of 23 primary lesions (91.3%). In 8.7% (2/23) a second series of treatments was required. Using RFA, complete necrosis was achieved in 85% of lesions (22/26) and partial necrosis in 15% (4/26). Complications included low fever (3 patients), high fever and abscess formation (1 patient), peri-tumoral necrosis (1 patient ) and portal vein thrombosis (1 patient ).

Conclusions: Our preliminary results confirm that PEI and RFA are an effective and safe option for treating hepatic tumors in patients unfit for surgery.
 

Background: Inflammatory mediators, including cytokines and reactive oxygen species. are associated with the pathology of chronic liver disease. Hepatocytes are generally considered as targets but not producers of these important mediators.

Objectives: To investigate whether cells of hepatocellular lineage are a potential source of various cytokines we estimated the expression and secretion of tumor necrosis factor alpha, transforming growth factor beta 1 and interleukins I beta, 6 and 8 in the culture of well-differentiated human HepG2 cells treated for 24 hours with ethanol, acetaldehyde and lipopolysaccharide. Lipid peroxidation damage, glutathione content and glutathione perox­idase, catalase and superoxide dismutase activity were also determined.

Methods: HepG2 cells were treated for 24 hours with ethanol (50 mM), acetaldehyde (175 ìM) and LPS (1 ìg/ml). TNF-á, TGF­-â, L-1â, IL-6 and IL-8 mRNA were determined by reverse transcriptase polymerase chain reaction and secretion by en­zyme-linked immunoassay. Lipid peroxidation damage, glutathione content and antioxidant enzyme activities were determined spectrophotometrically.

Results: Exposure to ethanol for 24 hours induced the expression of TNF-á and TGF- â1. secretion of IL-1â and TGF-â₁ and decreased catalase activity. Acetaldehyde markedly increased TNF-á and IL-8 expression, stimulated IL-1â and IL-8 secretion, increased lipid peroxidation damage and decreased catalase activity, while LPS exposure induced the expression of TNF-á. TGF- â₁, IL-6 and IL-8, the secretion of TGF-â₁, IL-1â, IL-6 and IL-8, and a decrease in catalase activity. No change in GSH, GSHPx or SOD was found in any experimental condition.

Conclusions: The present studies confirm and extend the notion that hepatocytes respond to ethanol, acetaldehyde and LPS-producing cytokines. Oxidative stress produced by the toxic injury plays an important role in this response through up­regulation of inflammatory cytokines.