Catheter-acquired urinary tract infection

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1. Higgins JE, Chi IC, Wilkens LR, Hatcher RA. Patterns of Depo-Provera use in a large family planning clinic in the United States. J Biosoc Sci 1986; 18: 379-86. 2. World Health Organisation. Facts about injectable contraceptives: memorandum from a WHO meeting. Bull WHO 1982; 60: 199-210. 3. Thomas DB. Oral contraceptives and breast cancer: review of the epidemiologic literature. Contraception 1991; 43: 597-642. 4. Harlap S. Oral contraceptives and breast cancer: cause and effect? J Repro Med 1991; 36: 374-95. 5. Institute of Medicine. Oral contraceptives and breast cancer. Washington, DC: National Academy Press, 1991. 6. Contraceptive pill study points to poor compliance. Network 1988; 10: 5. 7. Westoff CF. Reproductive preferences: a comparative view. Columbia: Westinghouse Institute for Resource Development, 1991.

Catheter-acquired urinary tract infection Despite the use of aseptic insertion techniques and closed sterile drainage, bacteriuria develops in 10-27% of catheterised patients within 5 days.l The frequency of this complication is higher in women than in men. It is generally recommended that symptom-free patients with bacteriuria should not be treated while the catheter remains in-situ,2,3 and when the catheter is removed antibiotic therapy is initiated only if the patient becomes symptomatic. However, catheter-associated urinary tract infection (UTI) increases the risk of gram-negative bacteraemia fivefold4and lengthens hospital stay by 1-5 days/ Patients with bacteriuria at the time of catheter removal are also more likely to have symptomatic UTI during the year after catheterisation.66 These observations have encouraged a more active, preventive approach to the disorder. Antibiotics are of little or no use in preventing UTI in catheterisations lasting less than 37,8 or more than 14 days9,10 but their role in the 3-14-day group remains controversial. Prospective trialsll,12 have shown the effectiveness of antibiotics in preventing catheterassociated UTI in this group. Use of antibiotics within 48 hours of catheter removal reduced the risk of bacteriuria five-fold. 13 Bacteriuria per se does not always lead to complications; it is common in elderly women and increases with age in men. We do not know how often and how quickly bacteria introduced by the catheter invade tissues of the urinary tract and cause distant infections at non-urinary-tract sites. There are indications that infections of non-urinary prostheses can be acquired from the urinary tract during catheterisation; large trials will be needed to determine the incidence of such infections and the cost-effectiveness of prophylaxis. What about management of patients with bacteriuria after catheter removal? Although bacteriuria will often clear this is not always the case. Harding and colleagues14 lately reported that bacteriuria following catheter removal resolved spontaneously in only 36% of symptom-free women. 64% of women had persistent bacteriuria, and 26 % of these subsequently had symptoms that required antibiotic therapy. In women over 65 years, spontaneous clearance of bacteria was uncommon, and antibiotic therapy used to eradicate organisms was

less effective. Spontaneous clearance occurred more often with enterococcus than with Escherichia coli bacteriuria. Although this and other studies 15 suggest that treatment may be warranted for symptom-free patients who are found to have persistent bacteriuria after catheter removal, further controlled prospective trials of antibiotic use following catheter removal are required. Such studies need to address (a) how much morbidity and mortality is prevented by antibiotics; (b) the nature of the morbidity; (c) cost/benefit relations; and (d) which patients are most likely to benefit from eradication of symptomless bacteriuria. The pathogenesis of catheter infections has been related to the production of biofilms—collections of microorganisms and their extracellular products bound to a solid surface. Bacteria deep within the biofilm are more resistant to antibiotics and host defence mechanisms. Experimental evidence suggests that biofilm formation can occur on the internal surfaces of drainage systems and is important in the pathogenesis of catheter infection.16 Biofilms have been observed on all types of catheter material, including latex, silicone polyvinylchloride, and ’Teflon’-coated latexY Common urinary pathogens killed by antibiotics may persist in the biofilm and restart the cycle of infection. Thus, biofilm growth in the catheter or urine drainage bag may be critical in the continuation of catheter infection. 19 A coat of bacterial discourages hydrophilic polymer mandelic and certain colonisation;19 antiseptics--eg, and lactic acids-which are active against microorganisms growing as biofilms 18 may be more effective than other bladder washouts. The prevention of catheter-related UTI requires more than antibiotic therapy. 1. Kunin tract

CM, McCormick RC. Prevention of catheter-induced urinary infections by sterile closed drainage. N Engl J Med 1966; 274:

1155-61. 2. Butler HK, Kunin CM. Evaluation of specific systemic antimicrobial therapy in patients while on closed catheter drainage. J Urol 1968; 100: 567-72. 3. Warren JW, Anthony WC, Hoopes JM, Muncie HL Jr. Cephalexin for susceptible bacteriuria in afebrile, long-term catheterised patients. JAMA 1982; 248: 454-58. 4. Jepson OB, Olesen Larsen S, Dankert J, et al. Urinary-tract infection and bacteraemia in hospitalised medical patients: a European multicentre prevalence survey on nosocomial infection. J Hosp Infect 1982; 3: 241-52. 5. Givens CD, Wenzel RP. Catheter-associated urinary tract infections in surgical patients: a controlled study on the excess morbidity and costs. J Urol 1980; 124: 646-48. 6. Anderson JT, Heisterberg L, Hepjorn S, et al. Suprapubic vs transurethral bladder drainage after colposuspension/vaginal repair. Acta Obstet Gynecol 1985; 64: 139-43. 7. Martin CM, Brookrajlan EN. Bacteriuria prevention after indwelling urinary catheterisation. Arch Intern Med 1962; 110: 703-71. 8. Britt MR, Garibaldi RA, Miller WA, Hebertson RM, Burke JP. Antimicrobial prophylaxis for catheter-associated bacteriuria. Antimicrob Agents Chemother 1977; 1: 240-43. 9. Appleton DM, Waisbren BA. The prophylactic use of chloramphenicol in transurethral resections of the prostate gland. J Urol 1956; 75: 304-13. 10. Steward KD, Wood GL, Cohen RL, Smith JW, Mackowiak PA. Failure of the urinalysis and quantitative urine culture in diagnosing symptomatic urinary tract infections in patients with long-term urinary catheters. Am J Infect Control 1985; 13: 154-60.

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Verbrugh HA, Mintjes-de Groot AJ, Andresse R, Hamersma K, van Dijk A. Postoperative prophylaxis with norfloxacin in patients requiring bladder catheters. Eur J Clin Microbiol Infect Dis 1988; 7:

490-94. 12. Little PJ, Pearson S, Peddie BA, Greenslade NF, Utley WLF. Amoxicillin the prevention of catheter-induced urinary infection. J Infect Dis 1974; 129 (suppl): 241-42. 13. Hustinx WNM, Mintjes-de Groot AJ, Verkooyen RP, Verbrugh HA. Impact of concurrent antimicrobial therapy on catheter associated urinary tract infection. J Hosp Infect 1991; 18: 45-56. 14. Harding GKM, Nicolle LE, Ronald AR, et al. How long should catheter acquired urinary tract infection in women be treated? Ann Intern Med

1991; 114: 713-19. 15. Warren JW. Catheter-associated urinary tract infections. Infect Dis Clin N Am 1987; 1: 823-54. 16. Nickel KC, Grant SK, Costerton JW. Catheter-associated bacteriuria: an experimental study. J Urol 1985; 26: 369-75. 17. Ramsay JW, Garnham AJ, Mulhall AB, et al. Biofilms, bacterial and bladder catheters. A clinical study. Br J Urol 1989; 64: 395-98. 18. Stickler D, Dolman J, Rolfe S, Chawla J. Activity of antiseptics against Escherichia coli growing as biofilms on silicone surfaces. Eur J Clin Microbiol Infect Dis 1989; 8: 974-78. 19. Roberts JA, Kaack MB, Fussell EN. Bacterial adherence to urethral catheters. J Urol 1990; 264: 262-69.

Over

ninety

We are ambivalent about advanced age. Admiration for those approaching their century as outstanding examples of triumph over adversity may be tempered by thoughts of old age as a time of decline and dependence; a dwindling of opportunities; a period of despondency and inevitable death. We fear frailty and poverty, incontinence, immobility, and intellectual

impairment. In developed countries, the very old are the fastest growing group in the population. For example, in 1981, there were almost 150 000 people over the age of 90 in England and Wales; at the millenium, there will be twice that number. Until now we have known very little about the lives of the 90s: who they are, where they live, what they do, how they see themselves, the state of their health, and the support they need. A study1 of 200 very old people living in eight provincial English towns is an important contribution to understanding of our oldest elders. Who survives to a great age? A high proportion of such people have a family history of longevity, are from the middle classes, and avoided the severe infectious diseases of childhood. Very old women outnumber their male counterparts by four to one. The over-90s cite moderation as the main reason for living so long: although 50% of them enjoy alcohol, very few drink heavily and only a tiny proportion of old men still smoke. No surprises here, perhaps, but those who proselytise about the evils of animal fats might ponder the observation that 81 % of people over 90 enjoy meat every day and over 67% eat butter. Half of all those over 90 still live at home, two-fifths living alone, and their houses are usually in good order. Nearly half of them go outside every day, although very few use public transport. A third of those living at home share the house with their children, and families provide most home care. Informal carers are committed and are happy to go on providing help and support; most cope well, but some

feel overburdened and resent the restrictions imposed them by their filial duties. The other half live in communal establishments-most in residential homes and some in nursing homes or long-stay hospital wards (by contrast, only 4% of those aged 75-84 are in institutional care). These establishments are usually of a reasonable or high standard and the positive and caring attitudes of the staff are much appreciated by the residents. However, some homes are criticised for staff shortages and lack of humanity; inflexibility, lack of autonomy, and poor ambience receive unfavourable comments. At first sight, the physical health of nonagenarians appears to be remarkably good. Nearly half of them have not been to hospital for the past 5 years and most of the remainder have only attended once over that period. Just a third have regular contact with their family doctor and only half of those living alone receive any help from district nurses, health visitors, or social services. Over 90% of those living at home are fully continent; two-thirds never have trouble sleeping; only two-fifths take analgesics. Nevertheless, most have at least one chronic disorder, usually deafness, impaired vision, or joint pains, each of which affected half the population sample. In functional terms, the daily living activities that proved most troublesome were cutting toe nails, preparing meals, and bathing. The presence of chronic illness and disability does not inevitably mean that people can no longer enjoy an active life: old people are usually adept at adjusting to these disadvantages and are not necessarily handicapped by them. What is it like to be very old? Over 70% report that they are in good spirits, never feel lonely, and are free from worries. Most lead lives of dignity and contentment. Personal relationships provide the main source of happiness and there is frequent contact with families. Only 3 % either have no relatives or never see them. Even when people wake to a new morning for the 35 000th time they usually look forward to a fulfilling day. Most obtain solace from their spiritual beliefs and contemplate death with serenity. Politicians and planners need not be unduly alarmed by exaggerated predictions of a rising tide of totally dependent people who threaten to overwhelm the health services. Social services are right to emphasise community care because most old people want to be at home. However, we should recognise that most care in the community is provided by relatives, not professionals, and that those carers who are overburdened need more recognition, support, and relief. If we are serious about the quality of life of our more dependent oldest citizens, we should see what can be done to improve the staffing levels, attitudes, and ambience of homes and hospitals for the elderly. Medical researchers might direct more of their energies to the common visual, auditory, and rheumatological problems afflicting the very old. on

1.

Holme A. Life after ISBN 0-415041651.

Bury M,

ninety. London: Routledge, 1991. £35.