Problems with antibiotic resistance in Spain and their relation to antibiotic use in humans elsewhere

Antibiotic policy

There is a clear association between antibiotic use and resistance both on individual and population levels. In the European Union, countries with large antibiotic consumption have higher resistance rates. Antibiotic resistance leads to failed treatments, prolonged hospitalisations, increased costs and deaths. With few new antibiotics in the Research & Development pipeline, prudent antibiotic use is the only option to delay the development of resistance. Antibiotic policy consists of prescribing strategies to optimise the indication, selection, dosing, route of administration, duration and timing of antibiotic therapy to maximise clinical cure or prevention of infection whilst limiting the unintended consequences of antibiotic use, including toxicity and selection of resistant microorganisms. A secondary goal is to reduce healthcare costs without adversely affecting the quality of care. The purpose of this paper is to provide the evidence base of prudent antibiotic policy. Special emphasis is placed on urinary tract infections. The value and support of antibiotic committees, guidelines, ID consultants and/or antimicrobial stewardship teams to prolong the efficacy of available antibiotics will be discussed.

Control of multiply resistant cocci: do international comparisons help?

Antibiotic resistance has become a worldwide problem. However, the reasons for the uneven geographic distribution of antibiotic-resistant microorganisms are not fully understood. For instance, there are striking differences in the epidemiology of multiresistant gram-positive cocci between the USA and Germany. According to recent reports, the prevalence of high-level penicillin-resistant pneumococci (PRP), meticillin-resistant Staphylococcus aureus (MRSA), and vancomycin-resistant enterococci (VRE) in clinically relevant isolates of hospitalised patients in the USA and Germany are: PRP, 14% versus less than 1%; MRSA, 36% versus 15%; and VRE, 15% versus 1%. These disparities may be explained by several determinants: (1) diagnostic practice and laboratory recognition (all three pathogens); (2) clonal differences and pathogen transmissibility (VRE); (3) antibiotic prescribing practices (all three pathogens); (4) population characteristics, including extensive daycare exposure in the USA (PRP); (5) cultural factors (all three pathogens); (6) factors related to the health-care and legal system (all three pathogens); and (7) infection-control practices (MRSA and VRE). Understanding these determinants is important for preventing further spread of multiresistant cocci within the USA. A rational approach to national surveillance is urgently needed in Germany to preserve the favourable situation and decrease MRSA transmission. Finally, we suggest that a macro-level perspective on antibiotic resistance can broaden the understanding of this worldwide calamity, and help prevent further dissemination of multiply resistant microorganisms.

Quality measures of antimicrobial drug use

Antimicrobial use is the major determinant in the development of resistance. Many parameters of importance for optimal quality of antimicrobial therapy have already been defined. Maximal efficacy of the treatment should be combined with minimal toxicity at the lowest cost. Quality of antimicrobial drug use is dependent on knowledge of many aspects of infectious diseases. Considering efficacy, many of our indications for antimicrobial use need critical evaluation. Irrational use should be discouraged. Avoidance of the development of resistance is a quality parameter that will need increasing attention. This paper reviews the well-established factors that may influence the appropriateness of pharmacotherapy with antimicrobial drugs. It cites recent evidence supporting principles of prudent prescribing and gives an overview of audits that have addressed these parameters. Measures relating to resistance are discussed.

Non-hospital consumption of antibiotics in Spain: 1987-1997

Spain has one of the highest incidences of bacterial resistance to antimicrobials, possibly linked to drug consumption patterns. Using Ministry of Health and Consumer Affairs records, data were obtained on non-hospital sales of antibiotics for the period 1987-1997, and equivalents calculated in weight of active drug ingredient and defined daily doses per 1000 population per day (DDD/1000/day). The number of packages sold declined from 75 million in 1987 to 55 million in 1997. None the less, there was a gradual yet steady rise in consumption in tonnage terms (249 to 275 tonnes). Furthermore, in terms of DDD/1000/day, consumption rose sharply until 1995 and then held steady at 21 DDD/1000/day, a level comparable to the mean for other developed countries. Penicillins were the group to register the highest consumption in Spain, followed-in the latter years of the study-by macrolides, cephalosporins and quinolones. The marked rise in these latter three groups was noteworthy. Despite the decrease in the number of packages sold, antibiotic consumption in Spain has risen. This consumption pattern is different from that of other European countries and might serve to explain differences in the generation of resistance.

A double-blind, randomized, controlled multicentre study to compare the efficacy of ciprofloxacin with pivampicillin as oral therapy for epididymitis in men over 40 years of age

OBJECTIVE

To compare the efficacy and safety of ciprofloxacin 500 mg orally twice daily with pivampicillin 700 mg orally twice daily for 10 days in men with acute epididymitis and over 40 years of age.

PATIENTS AND METHODS

The study comprised 172 men who entered a prospective, controlled, randomized, double-blind, trial of pivampicillin and ciprofloxacin. The median (range) age of the 158 patients eligible for the efficacy analysis was 58 (41-85) years; 41% had previously had a urinary tract infection and 27% had previously had epididymitis. Only one patient had a urethral catheter and 38% were sexually active. About half of the patients were admitted to hospital.

RESULTS

No bacteria could be cultured from samples in 53% of the patients; Escherichia coli could be cultured from 35% and the remaining isolates were the expected urinary pathogens. None of the patients had Gonococci and only one in each group had Chlamydia. Mycoplasma hominis was detected in three patients only and M. genitalium was detected in three, while Ureaplasma was detected in 24 (15%). The treatment failed in 48 patients; in 15 of 76 (20%) receiving ciprofloxacin and in 33 of 82 (40%) receiving pivampicillin. This corresponds to a reduction in the risk of failure of 20.5% (95% confidence limits 6.6-40.2%, P=0. 006). The principal cause of failure was an unsatisfactory clinical response requiring changed antibiotic treatment in 27 patients; adverse events were responsible for failure in 14. The in vitro resistance of cultured bacteria was low in both groups, at approximately 4%. Adverse events, mainly gastro-intestinal, occurred in 17 of 83 (21%) patients starting on ciprofloxacin and in 33 of 89 (37%) receiving pivampicillin (P=0.04).

CONCLUSION

For epididymitis in men over the age of 40 years ciprofloxacin 500 mg orally twice daily is more effective than pivampicillin 700 mg orally twice daily. Furthermore, ciprofloxacin has a lower incidence of adverse events.

A population-based study of antibiotic prescriptions for Danish children

BACKGROUND

The aim of the study was to examine the use of systemic and topical antibiotics in relation to age and sex in Danish children.

METHODS

We used the Pharmacoepidemiological Prescription Database to identify the individual prescriptions of antibiotics provided for all 0-to 15-year-old children in North Jutland County, Denmark, during 1997. The population was approximately 95000 children.

RESULTS

We identified 44640 prescriptions for systemic antibiotics. The annual prescription rate was highest in the 1- to 2-year-olds, with 945 prescriptions/1000 children/year. One-half of these children received at least 1 prescription, and 12% received 3 or more prescriptions. Among the 11- to 15-year-old children 17% received one or more prescriptions. Overall 88% of the prescriptions were penicillins and 10% were macrolides. In children younger than 3 years 57% of prescriptions were for broad spectrum penicillins, but in children older than 6 years penicillin V was the most frequently used antibiotic. We identified 12 661 prescriptions for topical antibiotics used in eye infections. The prescription rate peaked in the 1- to 2-year-old children, one-third of whom received at least 1 prescription.

CONCLUSIONS

Almost two-thirds of the 0- to 2-year-old children in the population were treated with either systemic or topical antibiotics during 1 year. Physicians prescribe mostly penicillins, but the proportion of broad spectrum penicillins for young children was so high, however, that enforcement of national guidelines should be reconsidered.