The prevalence of ampicillin, cephalosporin and sulphonamide resistance amongst urinary tract pathogens

Treatment of bacteriuria in pregnancy with single dose fosfomycin trometamol: a review

Bacteriuria in pregnancy occurs in about one in 20 pregnant women and is usually initially asymptomatic. It is an important marker for acute symptomatic infection (often pyelonephritis) later in pregnancy, which occurs in about one in four bacteriurics. Several considerations surround the antibiotic treatment of the asymptomatic infection; these include a low frequency of in vitro resistance to the agent used, lack of toxicity to the foetus, a low incidence of gastrointestinal side effects, good compliance and proven efficacy. Fosfomycin trometamol seems to fit these requirements. In three controlled studies (two multicentric) 250 patients were treated with fosfomycin trometamol in a 3 g (as fosfomycin) single dose; 197 patients were given one of three other agents. Cure rates for fosfomycin trometamol were 77-94% (68-94% for other agents), which was satisfactory in an infection which is sometimes difficult to eradicate. Further studies are needed in this important but accessible group of patients. Opportunities should be taken to study more foetal outcomes and provide more data on gastro-intestinal tolerability.

Antimicrobial sensitivities in urinary tract infections in men

Six-thousand-seven-hundred and forty-nine positive urine cultures from a large metropolitan Veterans Administration hospital were analyzed with respect to the organisms isolated and their antimicrobial sensitivities. A "predicted therapeutic efficacy index" was calculated for each antimicrobial agent tested. Gram-negative pathogens accounted for 84% of the infections. Proteus infections outnumbered those due to strains of Escherichia coli. Gentamycin was found to be the most effective antimicrobial agent.

The aminopenicillins: development and comparative properties

In this review we have compared and contrasted the antibacterial and pharmacological properties of the aminopenicillins currently available. It is apparent that there is little hard evidence (except in the case of thphoid fever) that either amoxycillin or the pro-drug esters of ampicillin are significantly more effective than ampicillin itself, despite their better absorption and higher serum levels. However, amoxycillin and the ampicillin pro-drug esters do cause fewer bowel side-effects than ampicillin, which may justify their use despite the extra cost involved. The problem of susceptibility to penicillinases is unlikely to be solved by modification of the aminopenicillin molecule. A more likely solution is administration of these substances with beta-lactamase inhibitors such as clavulanic acid. Trials with such combinations are already under way.