The menopause is associated with a dramatic fall in the production of oestrogens, which causes a rise in vaginal pH from a reduction in lactobacilli. This makes the lower genitourinary tract more susceptible to infection with pathogenic organisms. Colonisation of the vaginal introitus with pathogenic bacteria is more common and heavier in women who are susceptible to recurrent urinary tract infection (UTI).¹

The epithelium of the bladder and urethra also undergo atrophic changes and this can lead to atrophic cystitis and the formation of a urethral caruncle. The lower part of the urethra is sensitive to oestrogens. In some cases the cause of symptoms is interstitial cystitis. Postmenopausal women are therefore at increased risk not only of recurrent urinary tract infections, but also of dyspareunia, vaginal irritation, pruritus, pain and also symptoms of urgency, frequency, dysuria and urinary incontinence.

Epidemiology

• In women aged over 65 the prevalence of UTI is said to be as high as 20%.²

Risk factors

Presentation

Symptoms may include:

• Dysuria.
• Dyspareunia.
• Pruritus vulvae (this does not necessarily imply vaginal thrush).
• Urinary urgency.
• Frequency of micturition.
• Urinary incontinence.

Examination

Abdominal examination always precedes vaginal examination, or very large abdominal masses may be missed.
Many surgeries stock only disposable Cusco's specula but, if available, the instrument of choice is the Sims' speculum. Performing this examination with a Cusco's speculum is very much more difficult.

Use a Sims' speculum with the patient in the left lateral position (or right lateral if you are left-handed).

• Note any vaginal atrophy.
• With the Sims' speculum retracting the posterior vaginal wall, ask her to bear down. Note any cystocele or uterine descent.
• Ask her to cough - is there slight leakage from her bladder?
• Ask her bear down again and gently slip the speculum down and out, noting any rectocele as it descends.

Differential diagnosis

• Diabetes predisposes to infections of the genital tract.
• Fibroids can cause pressure on the bladder if very large. Smaller ones tend to atrophy after the menopause, but those larger than 5 cm do not.

Investigations

• Dipstick urine testing may show glucose, suggesting possibly undiagnosed diabetes. Nitrites suggest urinary infection.
• Midstream urine should be sent for culture and sensitivity. With persistent symptoms, repeated urine tests may help to distinguish between recurrent infection and failure to eradicate infection.
• If symptoms do not subside, then investigation may include cystoscopy with biopsy, urography and urodynamic studies. If there is haematuria that does not resolve rapidly on treating infection, then further investigation is required.

Management

• Treat urinary tract infection on the basis of laboratory results. Resistant infection will require longer courses of antibiotics.
• Hormone replacement therapy (HRT) will help to reverse the atrophic changes, but any therapeutic role for oral oestrogens remains uncertain.³
• Vaginal oestrogens have been shown in controlled trials to reduce the incidence of UTIs in postmenopausal women.^5,4
• If related to sexual intercourse, consider a prophylactic quinolone to be taken after intercourse, as well as a vaginal lubricant and voiding after intercourse.
• For interstitial cystitis, amitriptyline and pentosan polysulfate or intravesical instillations are used.^6,7
• There is very little evidence about either the efficacy or the safety of herbal remedies but the one that is often held to be the most effective is black cohosh. However, the Medicines and Healthcare products Regulatory Agency (MHRA) has issued a warning about the potential for liver toxicity.⁸

Prevention

• Regular drinking of cranberry juice (but not drinking a lactobacillus preparation) appears to reduce the risk of recurrent UTI.⁹
• Both long-term antibiotics and antibiotics after sexual intercourse seem effective.¹⁰

Document references

1. Stamey TA, Sexton CC; The role of vaginal colonization with enterobacteriaceae in recurrent urinary infections. J Urol. 1975 Feb;113(2):214-7. [abstract]
2. File TM Jr, Tan JS; Urinary tract infections in the elderly. Geriatrics. 1989 Aug;44 Suppl A:15-9. [abstract]
3. Hu KK, Boyko EJ, Scholes D, et al; Risk factors for urinary tract infections in postmenopausal women. Arch Intern Med. 2004 May 10;164(9):989-93. [abstract]
4. Perrotta C, Aznar M, Mejia R, et al; Oestrogens for preventing recurrent urinary tract infection in postmenopausal Cochrane Database Syst Rev. 2008 Apr 16;(2):CD005131. [abstract]
5. Dessole S, Rubattu G, Ambrosini G, et al; Efficacy of low-dose intravaginal estriol on urogenital aging in postmenopausal women. Menopause. 2004 Jan-Feb;11(1):49-56. [abstract]
6. Theoharides TC; Treatment approaches for painful bladder syndrome/interstitial cystitis. Drugs. 2007;67(2):215-35. [abstract]
7. Dawson TE, Jamison J; Intravesical treatments for painful bladder syndrome/ interstitial cystitis. Cochrane Database Syst Rev. 2007 Oct 17;(4):CD006113. [abstract]
8. Black Cohosh. Risk of liver problems, Medicines and Healthcare products Regulatory Agency (MHRA), July 2006
9. Jepson RG, Craig JC; Cranberries for preventing urinary tract infections. Cochrane Database Syst Rev. 2008 Jan 23;(1):CD001321. [abstract]
10. Franco AV; Recurrent urinary tract infections. Best Pract Res Clin Obstet Gynaecol. 2005 Dec;19(6):861-73. Epub 2005 Nov. [abstract]

Internet and further reading

• Cardozo L; Postmenopausal cystitis. BMJ 1996;313:129 (20 July)

Acknowledgements