The occurrence of Listeria species in pâté: the Cardiff experience 1989

Samples of 216 pâtés were examined for the presence of Listeria spp. between May and August 1989; 35% were contaminated with L. monocytogenes, 5% of samples having counts of greater than 10(4)/g. L. innocua was recovered from 2% of samples but no other species was isolated. Five serotypes of L. monocytogenes were represented (1/2, 4b, 4b(X), 4 not 4b or 4b(X), and NT), 4b was the predominant serotype and multiple serotypes were found in eight pâtés. The incidence of contamination with L. monocytogenes was greater in stored pâté (46%) than display pâté (30%). Sampling over a 21-day period showed an apparent increase in numbers of L. monocytogenes in 6 of 7 samples with multiple serotypes represented. There was no correlation between contamination of pâté by L. monocytogenes and the presence of coliforms. Comparisons are made between the contamination of soft cheese and pâté.

Salmonella enteritidis phage type 4 infection: association with hen's eggs

Epidemiological and microbiological investigation of the four outbreaks of Salmonella enteritidis phage type (PT) 4 that occurred in Wales in 1988 implicated foods containing shell eggs from hens as the vehicle of infection. In a case-control study of sporadic cases there was a significant association between infection and egg consumption in the 3 days before illness. These findings provide data to support the warnings from the Departments of Health in the United Kingdom about risks of infection from eating raw or undercooked hens' eggs.

Improved blood free selective medium for isolating Campylobacter jejuni from faecal specimens

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Legionella pneumophila in a hospital water system following a nosocomial outbreak: prevalence, monoclonal antibody subgrouping and effect of control measures

Swabs and water samples from a hospital water system were cultured for legionellae over an extended period. Legionella pneumophila serogroup 1, including outbreak associated strains, were isolated in small numbers from approximately 5% of these samples despite implementation of the current DHSS/Welsh Office regulations. No cases of nosocomial legionnaires' disease were proven during the study. Physical cleaning and chemical sterilization of taps, and replacement of washers with 'approved' brands did not eradicate the organisms. Eradication of legionellae in hospital water supplies appears to be unnecessary in preventing nosocomial legionnaires' disease provided the current DHSS/Welsh Office recommendations are implemented.

Contribution of Gardnerella vaginalis to vaginitis in a general practice

In a study of 154 adult women who presented to their general practitioner with vaginal symptoms 30 (20%) had Gardnerella vaginalis on its own and 51 (33%) had G vaginalis in combination with anaerobes or known pathogens. Thirty one (20%) patients were culture negative. Those who were culture negative had fewer symptoms and signs of vaginitis than those with G vaginalis alone or G vaginalis plus anaerobes. Those with known pathogens had more symptoms and signs than those with G vaginalis alone or G vaginalis plus anaerobes. Those with known pathogens plus G vaginalis had the most severe signs and symptoms of vaginitis. It is concluded that G vaginalis can cause vaginitis on its own, and it makes vaginitis worse when present with other organisms. G vaginalis was also found in 30 (21%) of the 138 control patients who, although they presented "asymptomatically," had worse signs than control patients without G vaginalis. It seems that G vaginalis can occur in a spectrum ranging from the uncomplaining patient to those with severe vaginitis.

The disinfection of silicone-foam dressings

The efficiency of four commonly used antiseptics, chlorhexidine, povidone-iodine, cetrimide and sodium hypochlorite was compared in the disinfection of silicone-foam dressing used in the management of open granulating wounds. An in vitro model was first used to determine the minimum effective concentration of each antiseptic in killing a standard culture of Pseudomonas. The appropriate concentrations were then compared in comparative studies of clinical wounds. Chlorhexidine proved to be the most effective antiseptic, povidone-iodine and cetrimide were moderately successful, but sodium hypochlorite gave poor results. A subsidiary study looked at the problem of wound irritation by carry-over of the antiseptic. A rinse of the dressing after disinfection prevented irritation by chlorhexidine without compromising its antibacterial effect, but this procedure sometimes failed to prevent irritation when using the other antiseptic agents. It is concluded that chlorhexidine is the preferred cleansing agent in the management of silicone-foam dressings on both grounds of bacteriological efficiency and lack of wound irritation. It should be noted that Hibitane concentrate used in this work contains non-ionic detergent and a stabilizing agent. Pure preparations of chlorhexidine may not behave similarly.

Pilonidal sinus excision--healing by open granulation

A prospective study is reported of 100 pilonidal sinus excisions healing by open granulation. Delays in healing appeared to be due to infection, particularly by anaerobic bacteria. Comparisons are made between three groups studied consecutively - 30 wounds not treated with antibiotics, 20 given a fixed two-week course of metronidazole and 50 managed flexibly. In this last group, wound management was determined by clinical appearance; 24 wounds were clinically healthy throughout and received no antibiotic while 26 looked unhealthy initially or after an interval and were treated with metronidazole, supplemented in some cases with erythromycin. The best results were obtained in the group managed flexibly. It is considered that the problems of delayed healing are due to excisions which leave a wound of a shape ill-designed to maintain good drainage. Unhealthy wounds should be re-shaped if possible and treated early with a combination of metronidazole and erythromycin.

Urethral syndrome: a self limiting illness

Thirty nine adult women who were not pregnant and had the urethral syndrome in a general practice underwent detailed microbiological investigations. Patients monitored their own symptoms, and those with persisting symptoms were entered into a randomised controlled trial of treatment with doxycycline and placebo. Chlamydia trachomatis and Neisseria gonorrhoeae were not isolated and fastidious organisms were not causally associated with the urethral syndrome. Treatment with doxycycline showed no benefit; each episode of the urethral syndrome was short and self limiting and there were no recurrences in a median observation period of 12 months.

The use of Preston enrichment broth for the isolation of 'thermophilic' campylobacters from water

The application of Preston enrichment broth to isolation of 'thermophilic' campylobacters from water has been investigated. Enrichment substantially increased the yield of such organisms. The optimum timing for subculturing the broth was after 48 h incubation. Despite the addition of aerotolerant supplement to the broth the number and variety of isolates was greater when the broth was incubated microaerically than when it was incubated in air.

A comparative trial of pivmecillinam/pivampicillin and amoxycillin/clavulanate in the therapy of urinary tract infection in a general practice population

Fifty-eight patients seen in general practice presenting with symptoms of acute urinary tract infection were entered consecutively into an open randomized trial of 200 mg pivmecillinam plus 250 mg pivampicillin twice daily or 250 mg amoxycillin plus 125 mg clavulanate 3-times daily for 5 days. The results were analyzed in 41 patients with significant bacteriuria (23 on pivmecillinam/pivampicillin and 18 on amoxycillin/clavulanate). Both antibiotic combinations produced good overall bacteriological cure, but there were a considerable number of persisting symptoms despite the absence of significant bacteriuria. Eight patients in the pivmecillinam/pivampicillin group and 5 in the amoxycillin/clavulanate group had side-effects, principally thrush, vomiting and abdominal pain, and 1 patient from each group ceased treatment for this reason. Sensitivity profiles of urinary isolates (41 trial, 135 non-trial) to both combinations and to ampicillin and mecillinam showed that the majority were fully sensitive to amoxycillin/clavulanate and to a lesser extent to pivmecillinam/pivampicillin; resistance was highest to ampicillin.