Microbiological quality of ice in hospital and community.

A survey was undertaken in response to a report of a clinical infection which had been related to an ice-making machine on a hospital ward. A detailed study of the ice microflora of 27 ice-making machines was performed. In a subsequent survey, ice samples (N = 194) from establishments such as bars and hotels were examined for bacterial indicators of hygiene. Samples from hospital ice-making machines yielded low numbers of a wide range of potentially opportunistic micro-organisms, many of environmental rather than clinical origin. For ice sampled in the community, the total aerobic plate count (TAPC) at 37 degrees C for 95% of the samples was < 500 cfu/mL, and at 22 degrees C 75% had < 500 cfu/mL. Examination for coliforms showed that 69% of samples contained no coliforms, but 20% contained > 100 coliforms/100 mL. Escherichia coli was detected in three samples but in very low numbers. This report investigates the relevance of ice machines to the control of hospital infection, the hygiene of ice in the community, discusses the microbiological quality of ice and proposes possible guidelines.

Promoting a quality of service culture in health care: review of a Scottish initiative.

This paper is a review of a quality of service initiative which was carried out as a PICKUP Quality Project within the Scottish Health Service. This Quality Initiative took place between 1989 and 1990: before the emergence of The Patient's Charter. The aim of the review was to provide answers to a number of important questions which examined the perceptions of staff who took part in the Quality of Service initiative, identified parts of the process which were in need of substantial revision, and reported on the reactions of participants to the overall process. The methodology employed involved questionnaires and interview techniques. A number of problems were identified and, after examination, these were taken to indicate learning pointers for the future. It was evident that good quality of service training can be delivered, but only if it is clearly and appropriately tailored to the audience. It is also of fundamental importance to be familiar with the environment in which the organization is operating. In this instance, as is often the case for health care, there were considerable financial limitations in force at the time. These limitations heightened the general business sensitivity and showed that carrying through quality of service improvements involved the demonstration of commitment and the provision of resources.

Contamination of multi-use closed tracheal suction catheters: an in-vitro study.

The use of closed multi-use tracheal suction systems in ventilated patients is increasingly popular as it offers a number of potential physiological and microbiological advantages. As the use of these systems has been associated with an increased prevalence of tracheal colonization, effective self-cleaning mechanisms employed in these catheters are necessary. Using an in-vitro model we assessed the degree of catheter colonization in two multi-use catheter systems; Stericath and Trach-Care. Fifty of each catheter type were tested for colonization with five challenge organisms: Staphylococcus aureus (NCTC 6571); Pseudomonas aeruginosa (NCTC 10662); Haemophilus influenzae type b; S. epidermidis (slime producer); and S. epidermidis (slime non-producer). All five challenge strains had colonized both catheter types after 24 h and all 100 catheter tips were colonized. The extent and density of colonization was variable and interspecies variation in the pattern of catheter colonization was observed. The mean colonized lengths of Stericath catheters was 10.9 +/- 1.4 cm and of Trach-Care 2.7 +/- 1.3 cm (P < 0.0001).

An assessment of the hidden and total antibiotic costs of four parenteral cephalosporins.

The aim of this study was to compare the hidden costs, and their impact on total antibiotic costs, of ceftriaxone therapy with those of cefotaxime, ceftazidime and cefuroxime in nosocomial infection. The total antibiotic costs of 7-day standard courses of the 4 cephalosporins were compared. The costs were divided into 3 parts: (i) the cost of the drug itself; (ii) the preparation and administration (labour) costs; and (iii) the consumables and waste costs. The latter 2 costs together comprised the hidden cost of an antibiotic course. Hidden costs were higher for cefotaxime, ceftazidime and cefuroxime, which are normally administered 3 times a day, than for ceftriaxone, which is administered once daily. The percentage contribution of hidden costs to total antibiotic costs increased with decreasing antibiotic cost, and were lower with higher dosages of all antibiotics. With cefotaxime, ceftazidime and cefuroxime, and with ceftriaxone at the lower dosage given by bolus intravenous (IV) injection, the labour component of hidden costs exceeded the consumables/waste component. However, when costs were calculated for ceftriaxone administered at the higher dosage by IV infusion, the costs of consumables and waste were greater than the labour costs. Ceftriaxone had the lowest hidden costs of all the antibiotics studied. The total antibiotic cost of low dosage ceftriaxone (1 g per dose) was comparable with that of cefuroxime, and was substantially less than the costs of cefotaxime and ceftazidime. At the high ceftriaxone dosage (2g per dose), the total antibiotic cost of cefuroxime was less than that of ceftriaxone; however, the total antibiotic cost of ceftriaxone remained substantially less than that of cefotaxime or ceftazidime.

In vitro antimicrobial activity of imipenem in combination with vancomycin or teicoplanin against Staphylococcus aureus and Staphylococcus epidermidis.

The interaction between imipenem and two glycopeptides against staphylococci was examined for potential synergy. Imipenem in combination with vancomycin or teicoplanin exerted a synergistic or additive effect against a majority of Staphylococcus aureus and Staphylococcus epidermidis isolates tested by the checkerboard method. Synergistic inhibitory effects were frequently accompanied by synergistic bactericidal effects. For a proportion of bacterial isolates of both species, the demonstration of synergy by the checkerboard method was confirmed by time-kill studies using antibiotic combinations at the MICs or at achievable serum antibiotic levels. Only with a single isolate of Staphylococcus epidermidis was antagonism with either antibiotic combination recorded.

Haemophilus aphrophilus endocarditis.

We report a case of Haemophilus aphrophilus endocarditis involving mitral and tricupsid valves in a boy with congenital heart disease. He had received dental treatment without antibiotic cover. Prolonged high-dose ampicillin with gentamicin was necessary for cure. Short courses of ampicillin alone may not successfully treat H. aphrophilus.

Comparison of identification of Enterobacteriaceae by API 20E and Sensititre Autoidentification System.

Of 251 isolates of the Enterobacteriaceae identified to species level by API 20E, 208 (83%) were similarily identified by the Sensititre Autoidentification System. Both systems shared a common problem in that discrimination between species of the genera Klebsiella, Enterobacter, and Serratia was poor. The eight digit biocode generated by the Sensititre system for individual isolates is not reproducible and therefore not of epidemiological value.

The effect of exposure to mupirocin on the survival and recovery of sensitive Staphylococcus aureus strains.

A significant percentage survival, representing a large number of viable cells, can occur in a Staphylococcus aureus population exposed to concentrations of mupirocin up to 1,000 times the minimum inhibitory concentration. An elevated ratio of minimum inhibitory to minimum bactericidal concentration of mupirocin with staphylococci was recorded. Staphylococci which survive exposure to mupirocin may be less sensitive to the subsequent bactericidal action of the antibiotic. The observations may explain the re-colonisation with staphylococci seen in some studies.

An outbreak of infection with a methicillin-resistant Staphylococcus aureus in a special care baby unit: value of topical mupirocin and of traditional methods of infection control.

This report deals with the problems associated with a high incidence rate of methicillin-resistant Staphylococcus aureus in low birth weight infants in a regional special care baby unit. Strict isolation facilities were not used and the outbreak was promptly brought under control by the use of intensive traditional methods of infection control and the use of topical mupirocin in a paraffin base.

Value of charcoal media for recovering staphylococci incorporated in mupirocin ointment.

The use of charcoal blood agar supported a good recovery of staphylococci incorporated in Mupirocin ointment in a test in vitro system. The efficacy of this medium was particularly emphasised in the recovery of staphylococci damaged by six hours' exposure to Mupirocin. The media will be of value in following the progress of staphylococcal carriage or infection in patients or carriers being treated with topical Mupirocin.

Correlation between antibiotic sensitivity testing by conventional and conductivity measurements.

A high correlation in the susceptibilities of 44 strains isolated from clinical material to a variety of antimicrobial agents was found between the minimum inhibitory concentration and conductivity measurements. Some discrepancy was found for vancomycin and teicoplanin when tested against 21 strains of staphylococci. Similarly, discrepancies were seen with azlocillin, chloramphenicol and gentamicin when tested against strains of aerobic and facultatively anaerobic Gram-negative bacilli. In the majority of cases in which discrepancies were noted, this reflected differences in relative, and not absolute, susceptibility. With five strains of Pseudomonas, however, there was a poor correlation with three of four antibiotics studied. The advantage of this technique is that sensitivities are available within 4-6 h.

Biotypes of Klebsiella pneumoniae (sensu lato) and Enterobacter aerogenes characterised by differential substrate metabolism: application of the technique.

A biochemical typing method is described for Klebsiella pneumoniae (sensu lato) and Enterobacter aerogenes. The technique depends on differences in metabolism of five carbon substrates--glycerol, inositol, lactose, glucose, and xylose--at two concentrations. Reproducibility is satisfactory and is monitored by the incorporation of control klebsiellae of known biotype. The method has been used for 12 months in the surveillance of urinary tract colonisation in this hospital. Gut carriage of klebsiellae, implicated by several workers as a source of infection, was common among staff and new admissions. Many biotypes were represented which were sensitive to most antibiotic except ampicillin. Klebsiellae, all multiply resistant, were isolated most frequently from urine specimens in two orthopaedic wards. In a longitudinal study in these wards, a sequential dominance in urinary tract colonisation by two klebsiella biotypes was shown, which suggested the presence of cross infection or an environmental reservoir. Confirmatory evidence was obtained from capsular serotypes and R-factor studies.