2.9 UtIs in post-menopausal women

The vagina ordinarily contains only low numbers of Gram-negative enteric bacteria because of competition from the resident microbial flora. Lactobacilli account for the low vaginal pH. They tend to be less abundant in post-menopausal women and after antimicrobial therapy. Oestrogens are presumed to exert a protective force against recurrent UTIs in post-menopausal women because they enhance the growth of lactobacilli and decrease vaginal pH (55). Gram-negative enteric bacteria do not ordinarily colonize the vagina in post-menopausal women unless these women are prone to recurrent UTIs (56). In post-menopausal women with recurrent UTIs, therapy with oral (57,58) or intravaginal oestriol (55) was able to reduce significantly the rate of recurrence. For other patients, an antimicrobial prophylactic regimen (see previously) should be recommended in addition to hormonal treatment.

In case of an acute UTI, the antimicrobial treatment policy is similar to that in pre-menopausal women. Short-term therapy in post-menopausal women is not, however, as well documented as in younger women. Raz et al. (59) published a study in post-menopausal women (mean age 65 years) with an uncomplicated UTI in which ofloxacin, 200 mg once daily for 3 days, was significantly more effective in both short- and long-term

follow-up than a 7-day course of cephalexin, 500 mg four times daily, even though all the uropathogens were susceptible to the two agents. In the case of a recurrent UTI, a urological or gynaecological evaluation should be performed in order to eliminate a tumour, obstructive problems or a genital infection.

2.10 Acute uncomplicated UTIs in young men

2.10.1 Pathogenesis and risk factors

It has been conventional to consider all UTIs in men as complicated because most of those that occur in the new-born, the infant or the elderly are associated with urological abnormalities, bladder outlet obstruction or instrumentation. A UTI in an otherwise healthy adult man between the ages of 15 and 50 years is very uncommon. In Norway, a rate of 6-8 UTIs per year per 10,000 men aged 21-50 years has been reported (60). The large difference in the prevalence of UTIs between men and women is thought to be caused by a variety of factors, including the greater distance between the usual source of uropathogens (the anus and the urethral meatus); the drier environment surrounding the male urethra; the greater length of the male urethra; and the antibacterial activity of the prostatic fluid. It has become clear, however, that a small number of 15-50-year-old men suffer acute uncomplicated UTIs. The exact reasons for such infections are not clear, but risk factors associated with such infections include intercourse with an infected partner, anal intercourse and lack of circumcision (61); however, these factors are not always present.

2.70.2 Diagnosis

The symptoms of uncomplicated UTIs in men are similar to those in women. Urethritis must be ruled out in sexually active men using a urethral Gram stain or a first-voided urine specimen wet mount to look for urethral leucocytosis. A urethral Gram stain demonstrating leucocytes and predominant Gram-negative rods suggests E. coli urethritis, which may precede or accompany a UTI. Dysuria is common to both a UTI and urethritis. The aetiological agents that cause uncomplicated UTIs in men are also similar to those in women. Krieger et al. (62) noted that 93% of 40 uncomplicated UTIs in men were caused by E. coli.

2.10.3 Treatment

Due to the infrequency with which UTIs occur in this group of men, data from controlled treatment studies are non-existent. Empirical use of the agents discussed previously for uncomplicated cystitis or pyelonephritis in women are recommended. Nitrofurantoin should not be used in men with a UTI, since it does not achieve reliable tissue concentrations. For acute uncomplicated pyelonephritis, the use of a fluoroquinolone as initial empirical oral treatment is recommended in areas where the rate of E. coli resistance to fluoroquinolones is low (< 10%). Otherwise, alternative drugs have to be considered (see section).

Although it is possible that short-course treatment is effective in men with uncomplicated cystitis, there are no studies to support this practice. It is recommended, therefore, that such men receive a minimum of 7 days of therapy because of the relatively greater likelihood of an occult complicating factor in men compared with women. Also, longer treatment may reduce the likelihood of persistent prostatic infection.

The value of a urological evaluation in a man who has had a single uncomplicated UTI has not been determined. Urological evaluation should be carried out routinely in adolescents and in men with pyelonephritis and recurrent infections, or whenever a complicating factor is present.