Optimising antibiotic use in upper respiratory tract infections

Has your antibiotic prescribing for upper respiratory tract infections changed?

Prescribing of antibiotics has been falling for some time – from 24 million prescriptions dispensed in the year 1990–91 to 20 million in 2002–03.[1] A large part of this has been reduced prescriptions for upper respiratory tract infection (URTI), where use of an antibiotic is rarely of benefit.[2] Nonetheless, 35% of GP visits for generalised URTI in 2002–03 ended in a prescription for antibiotics.[3]

Patients are open to discussions about the role of antibiotics in URTIs

The most recent survey by NPS reveals that 90% of consumers now see use of antibiotics for coughs and colds as having disadvantages, as well as possible advantages[4] – this suggests that most people are aware that there are both risks and benefits to be weighed up when deciding if an antibiotic is appropriate. Health professionals have an opportunity to inform patients of the risks of antibiotic use, such as adverse effects and bacterial resistance, as well as the benefits.

Consider delayed antibiotic prescription as a strategy to reduce inappropriate antibiotic use

Non-specific URTIs are usually viral and are not altered in their course by antibiotics; acute otitis media, sinusitis and sore throat benefit little from antibiotic therapy, even when bacterial in aetiology. Prescribing symptomatic management is an alternative; however, some patients expect an antibiotic. Recent studies have confirmed that a delayed prescription is effective in reducing use.[5]

Asking patients to wait three or more days and only have antibiotics dispensed if the condition has not improved spontaneously may be useful when there is the expectation of a prescription. When discussion of the advantages and disadvantages of an antibiotic is difficult, delayed prescription may also be an opportunity to begin patient education without confrontation.[6]

Potential disadvantages of delayed prescriptions include patient confusion or a damaged perception of the prescriber.[7] Some trials have found that while most patients receiving delayed prescriptions were satisfied with their treatment, they were less satisfied than patients receiving immediate prescriptions. [8,9]

Resources for patients to help with appropriate antibiotic use

For your patients: Middle ear infection information sheet

A patient information sheet on middle ear infection is available from the NPS website. 

Symptomatic management “prescriptions” help patients with managing URTIs

The NPS Symptomatic management pad for acute URTIs and acute bronchitis assists doctors in explaining to their patients that viral URTIs do not require treatment with antibiotics and that symptoms can be managed in a variety of ways.

The NPS Symptomatic management pad for acute URTIs and acute bronchitis and other patient education brochures are available to download from the NPS website.

Using prescribing software to review your prescribing of antibiotics

Patients taking antibiotics can be identified using prescribing software packages, i.e. Genie, Locum, Medical Director or Medical Spectrum.

Instructions for searching for your patients on antibiotic therapy within prescribing software programs can be found on the NPS website.

You can use your prescribing software records to help you review the following points:

• Has your prescribing of antibiotics for non-specific URTIs decreased over the last 5 years?
• Has your prescribing of antibiotics for otitis media, sinusitis and tonsillitis decreased over the last 5 years?
• Has your selection of antibiotics changed more towards first-line choices?
• Does your antibiotic choice reflect the likely causative organism(s) for that particular condition?

Treatment of community-acquired pneumonia

Treat non-severe communityacquired pneumonia with empirical dual antibiotic therapy

Suspected pneumonia should be confirmed with a chest X-ray. If the case is not serious enough to warrant hospitalisation (i.e. Pneumonia Severity Index Class I or II – see NPS News 40), Australian guidelines recommend empirical dual oral therapy2:

amoxycillin* 1 g 8-hourly for 7 days PLUS EITHER

• doxycycline^† 200 mg for the first dose, then 100 mg daily for 5 more days

OR

• roxithromycin (Biaxsig, Rulide) 300 mg daily for 7 days

For patients with non-immediate penicillin hypersensitivity

cefuroxime (Zinnat) 500 mg 12-hourly for 7 days (in the place of amoxycillin; with doxycycline or roxithromycin as above)

For patients with immediate penicillin hypersensitivity

gatifloxacin (Tequin)^‡ or moxifloxacin (Avelox)^†† 400 mg daily for 7 days (as monotherapy)

_{* Alphamox, Amohexal,Amoxil, Bgramin, Cilamox, Maxamox, Moxacin}

_{† Doryx, Doxsig, Doxy, Doxyhexal, Doxylin, Vibramycin}

_{‡ gatifloxacin is not available on the PBS but is subsidised on the RPBS}

_{†† moxifloxacin is an authority-required PBS listing for community-acquired pneumonia with immediate penicillin hypersensitivity}

Dual therapy covers the likely causative pathogens. Most strains of Streptococcus pneumoniae seen in Australia are susceptible to high-dose penicillin.[10] Other potential pathogens such as Mycoplasma pneumoniae are covered by the macrolide or doxycycline.[10]

Reserve cephalosporins and quinolones for patients with penicillin hypersensitivity

Widespread use of newer antibiotics can lead to the early selection of resistance to these agents. The quinolones, gatifloxacin and moxifloxacin, have not proven to be more effective than beta-lactams in non-severe communityacquired pneumonia.[11] There are only limited data on the comparative efficacy of gatifloxacin or moxifloxacin in severe community-acquired pneumonia.[12] Keeping our current reserve agents effective is essential.[13]

Community-acquired pneumonia treatment guidelines apply to both hospitals and primary care

Hospital treatment of community-acquired pneumonia is also empirical, unless a specific pathogen is identified or suspected.[2] Recommended empirical oral therapy in hospitals is the same as that in primary care. This includes patients started on intravenous antibiotics who have been stabilised and switched to oral medication on discharge.[2]

Treatment of urinary tract infection

Choose the appropriate duration of antibiotic treatment for the type of patient. The length of antibiotic treatment for urinary tract infection (UTI) varies by antibiotic and with pregnancy, sex and age (Table 1). Note that for acute cystitis in non-pregnant women, trimethoprim needs only a 3-day, rather than a 5-day course.

Table 1. Recommended length of antibiotic therapy for acute uncomplicated UTI or pyelonephritis (days)[2]

_{* serious pyelonephritis requires parenteral treatment, see Therapeutic Guidelines: Antibiotic
† avoid in pregnancy
‡ second-line
†† avoid in children unless necessary on microbiological grounds}

Quinolones are always second-line treatment in urinary tract infections

Most pathogens are sensitive to the recommended first-line drugs. Reserve quinolones such as norfloxacin and ciprofloxacin for second-line treatment, as they are the only oral drugs available to treat urinary tract infections due to Pseudomonas aeruginosa and other multiresistant bacteria.[2]

Avoid amoxycillin alone in empirical therapy

Organisms cultured from UTIs may be resistant to amoxycillin in half of all cases.[14] Amoxycillin alone should only be used when culture indicates the presence of susceptible organisms.[2]

Obtain a urine culture when necessary 

Empirical therapy is appropriate in most cases. However, a culture is required where there is increased likelihood of microbial resistance or risk of serious infection (Table 2).

Table 2. Patients and cases where urine culture is necessary[2,14,15]

Do not treat asymptomatic bacteriuria in patients over 60 years of age

The prevalence of asymptomatic bacteriuria may be as high as 50% in some elderly populations; people in aged-care facilities are particularly likely to be affected.[16] Asymptomatic bacteriuria is a benign condition and treatment with antimicrobials does not appear to improve morbidity and mortality.[16] A positive dipstick or culture in the absence of other symptoms is not an indication for antibiotic therapy.[17]

Expert reviewer

A/Prof Keryn Christiansen

Head, Department Microbiology & Infectious Diseases

Royal Perth Hospital Perth,WA

References

1. Data provided by Drug Utilisation Sub Committee (DUSC), Department of Health
   and Ageing, Canberra.
2. Therapeutic Guidelines: Antibiotic. 12th ed; 2003.
3. Britt H, et al. General practice activity in Australia 2002– 03. Canberra: Australian Institute of Health and Welfare; 2003. Report No.: 14.
4. National Prescribing Service. Evaluation Report No. 7. Sydney; 2004.
5. Arroll B, et al. Br J Gen Pract 2003;53:871–7.
6. Arroll B, et al. BMJ 2003;327:1361–2.
7. Arroll B, et al. J Fam Pract 2002;51:954–9.
8. Dowell J, et al. Br J Gen Pract 2001;51:200–5.
9. Little P, et al. BMJ 2001;322:336–42.
10. Johnson PD, et al. Med J Aust 2002;176:341–7.
11. Mills GD, et al. BMJ 2005;330:456.
12. Finch R, et al. Antimicrob Agents Chemother 2002;46:1746–54.
13. Collignon PJ. Med J Aust 2002;177:325–9.
14. PRODIGY Guidance – Urinary tract infection (lower) – women (last revised January 2004); accessed 12 January 2005.
15. PRODIGY Guidance – Urinary tract infection (lower) – men (last revised September 2004); accessed 14 April 2005.
    
16. Raz R. Int J Antimicrob Agents 2003;22 (Suppl 2):45–7.
17. Shortliffe LM, McCue JD. Am J Med 2002;113 (Suppl 1A):55S–66S.