Liver abscess: What determines the prognosis?

Records of all patients with liver abscess who presented to a teaching hospital between 1979 and 1986 were reviewed in order to determine prognostic factors and optimal treatment. Of 32 patients, the diagnosis was made ante-mortem in 30, and 24 patients survived. Patients who died tended to be older and more likely to exhibit confusion and other features of systemic toxicity at presentation. Fine needle aspiration, guided by computerized tomography, provided the correct diagnosis in 18 of 19 patients. Of 24 patients with isolated abscesses (1 or 2) 22 survived, whereas six of eight patients with multiple (more than 2) abscesses died ( P < 0.001). Aspirates from patients who survived appeared to grow anaerobes more commonly (NS), whereas those from non-survivors more often grew multiple organisms which usually included Gram-negative bacilli ( P < 0.01). All patients received broad spectrum antibiotics and a drainage procedure was carried out in 26. Of 19 patients treated by percutaneous drainage, 12 recovered, one required hepatic resection before recovering, and six died (four with multiple abscesses). Of nine patients (all with 1–2 abscesses) treated by open drainage, all eventually recovered, but three needed additional procedures. Six of eight non-survivors compared with four of 24 survivors had predisposing biliary sepsis ( P < 0.01). It is concluded that isolated liver abscesses are relatively benign, commonly grow anaerobes, and are usually resolved with antibiotics and drainage (closed or open), whereas multiple abscesses occur in sicker, older patients who are usually jaundiced with uncontrolled biliary sepsis. The prognosis in patients with multiple liver abscesses is poor irrespective of treatment.     

The Mechanisms of Atrial Fibrillation

In this article we have reviewed the mechanisms of atrial fibrillation (AF) with special emphasis on the thoracic veins. Based on a number of features, the thoracic veins are highly arrhythmogenic. The pulmonary vein (PV)-left atrial (LA) junction has discontinuous myocardial fibers separated by fibrotic tissues. The PV muscle sleeve is highly anisotropic. The vein of Marshall (VOM) in humans has multiple small muscle bundles separated by fibrosis and fat. Insulated muscle fibers can promote reentrant excitation, automaticity, and triggered activity. The PV muscle sleeves contain periodic acid-Schiff (PAS)-positive large pale cells that are morphologically reminiscent of Purkinje cells. These special cells could be the sources of focal discharge. Antiarrhythmic drugs have significant effects on PV muscle sleeves both at baseline and during AF. Both class I and III drugs have effects on wavefront traveling from PV to LA and from LA to PV. Separating the thoracic veins and the LA with ablation techniques also prevents PV-LA interaction. By reducing PV-LA interaction, pharmacological therapy and PV isolation reduce the activation rate in PV, intracellular calcium accumulation, and triggered activity. Therefore, thoracic vein isolation is an important technique in AF control. We conclude that thoracic veins are important in the generation and maintenance of AF.     

Bilateral basal ganglia lesions in patients with end-stage diabetic nephropathy (Brief Communication)

Summary:   Acute movement disorder associated with reversible bilateral basal ganglia lesions is an increasingly recognized syndrome in patients with end-stage renal disease, especially in the setting of concurrent diabetes mellitus. We report an elderly man with end-stage diabetic nephropathy treated by daily automated peritoneal dialysis who developed subacute symptoms of gait disturbance, dysarthria, dysphagia and lethargy. Computed tomography and magnetic resonance imaging of the head revealed bilateral symmetrical basal ganglia lesions. Repeat imaging 3 weeks later showed that these lesions had regressed spontaneously. However, his neurological symptoms improved slowly. These findings were similar to 23 other cases in the literature. Review of these cases shows that clinical features were predominantly bradykinesia, gait disturbance and concurrent metabolic acidosis (observed in 90% of cases). The pathogenesis of this condition has not been clearly defined, but uraemia may be an aggravating factor in predisposed patients, particularly in the presence of diabetic microvascular disease. There is no specific treatment for this condition; supportive measures are the mainstay of management. In the majority of patients, neurological improvement lags behind regression of basal ganglia lesions seen with neuroimaging, and the long-term outcome is variable.     

The use of prostate-specific antigen testing in the detection of localized prostate cancer: Current opinion and urological practice in the United Kingdom

Background: The prostate-specific antigen (PSA) test and itsinterpretation plays a crucial role in the detection of earlylocalized prostate cancer. However, inaccuracy of the test,inability to predict the aggressiveness of the disease and thelack of evidence about the comparative effectiveness of treatmentshave led to major dilemmas in considering whether to employthe PSA test and which cut-off points to use in interpretingits results. The aim of this study was to evaluate current urologicalpractice in the UK regarding the use of PSA testing. Methods:A postal questionnaire survey of all consultant urologist membersof the British Association of Urological Surgeons was conducted.Statistical analysis included proportional odds regression modelsto examine factors associated with urologists' preferences fordifferent definitions of ‘normal’ PSA cut-off levels.Results: The survey response rate was 60%. The majority of consultanturologists applied the PSA test routinely. There was a highlevel of agreement amongst UK urologists on normal PSA cut-offpoints (<4.0 ng/ml) for asymptomatic men under 60 years ofage. There was very wide variation in the definition of normalPSA cut-offs for older (60 years) asymptomatic men. A preferencefor lower cut-off points, leading to investigation with ultrasoundand biopsy, was significantly associated with larger urologydepartment size, the presence of a prostate cancer subspecialistin the department and relatively short length of specializationin urology. Conclusions: Prostate cancer screening and earlydetection practices and reported incidence rates of the diseaseare likely to be influenced by variation in urologists' interpretationsof PSA. Despite increasing evidence in favour of lower PSA cut-offlevels, particularly for younger men (<60 years), urologistsin the UK are divided over their interpretation. Men, particularlyover age 60 years, have varying chances of further investigationfollowing PSA testing. Any trial of prostate cancer screeningor treatment should take this potential variation into account.Standard protocols for PSA interpretation should be implemented.     

Toll-like receptor 2 as a major gene for asthma in children of European farmers

BACKGROUND: The finding that the prevalence of asthma and allergies is less frequent in children raised on animal farms has led to the conjecture that exposure to microbial products modifies immune responses. The toll-like receptors (TLRs) represent an evolutionarily conserved family of innate immunity receptors with microbial molecules as ligands. OBJECTIVES: We reasoned that polymorphisms in genes encoding TLRs might modulate the protective effects observed in farming populations. METHODS: Farmers' and nonfarmers' children living in rural areas in Austria and Germany and who were enrolled in the cross-sectional ALEX study were genotyped for single nucleotide polymorphisms in the TLR2 and TLR4 genes. The frequencies of asthma, allergic rhinitis, and atopic sensitization were compared between the genotypes in relation to exposure to farming and endotoxin. RESULTS: Among farmers' children, those carrying a T allele in TLR2/-16934 compared with children with genotype AA were significantly less likely to have a diagnosis of asthma (3% vs 13%, P = .012), current asthma symptoms (3% vs 16%, P = .004), atopic sensitization (14% vs 27%, P = .023), and current hay fever symptoms (3% vs 14%, P = .01). The association between TLR2/-16934 and asthma among children of farmers was independent of atopy. No such association was found among children from the same rural communities but not living on farms. CONCLUSION: Our results suggest that genetic variation in TLR2 is a major determinant of the susceptibility to asthma and allergies in children of farmers.     

The effects of methadone on immune function among injecting drug users: a review

Methadone maintenance therapy is advocated as a major preventive strategy for the spread of the human immunodeficiency virus (HIV) and other blood-borne infectious agents among injecting drug users (IDUs) because of its effects in decreasing the frequency of injecting and presumably sharing of equipment. As an opioid agonist, methadone may share the direct and indirect immunoregulatory effects of other opioids, and thus affect susceptibility to, and the natural history of, HIV infection. Available evidence pertaining to methadone and immune function is reviewed. The long-term immunosuppression observed in heroin injectors on present (incomplete) evidence appears to be caused by factors associated with a drug-using lifestyle rather than by a direct action of heroin. Although data are conflicting, it is most likely that methadone does not significantly impair immune function and is safe for HIV-infected IDUs, possibly even allowing some improvement of immune function to occur. The increasing reliance placed on methadone maintenance to control the epidemic of HIV infection in IDUs requires that remaining uncertainties regarding methadone and immune function are clarified urgently.     

BIAS IN A SURVEY OF DRINKING HABITS

This paper presents data from a general population survey ofthree areas of Britain which manifest considerable differencesin official rates of problem drinking, yet show similar patternsand levels of alcohol consumption. Consideration of varioussources of bias (non-response, forgetting, selective under-reporting,and interviewer) suggest that they do not differentially influenceself-reported alcohol consumption in the three areas.