Management of urinary tract infections in pregnancy: a review with comments on single dose therapy

[Fosfomycin: an underrated antibiotic for urinary tract infections due to Escherichia coli]

OBJECTIVES

To evaluate the sensitivity patterns of Escherichia coli isolates obtained from urine specimens from patients with community-acquired urinary tract infections, with a special emphasis on fosfomycin trometamol for the treatment of UTI.

METHODS

Retrospective analysis of the sensitivity pattern of 16,227 E. coli isolates recovered from urine cultures performed at the Microbiology Laboratory of Madrid Area 11 from 1997 to 2000. The antimicrobial agents tested included ampicillin, amoxycillin-clavulanate, cephalotin, cefuroxime, trimethoprim-sulphamethoxazol, fosfomycin trometamol, nitrofurantoin, and ciprofloxacin. Antibiotic sensitivity testing was performed with the Vitek automatic microdilution system (bioMèrieux, France).

RESULTS

E. coli represented 80.1% of all uropathogens recovered. The percentages of sensitive strains to ampicillin, amoxycillin-clavulanate, cephalotin, cefuroxime, trimethoprim-sulphamethoxazol, nitrofurantoin, and ciprofloxacin were 42.25%, 81.5%, 58.75%, 87.5%, 70%, 94.75%, and 84.75%, respectively. Fosfomycin trometamol was the antibiotic with the highest activity against E. coli, with 95.5% of sensitive isolates.

CONCLUSIONS

Fosfomycin trometamol (single dose) is a good alternative that should be considered for the treatment of non-complicated lower urinary tract infections.

Detection, significance, and therapy of bacteriuria in pregnancy. Update in the managed health care era

Profound physiologic and anatomic changes of the urinary tract during pregnancy contribute to the increased risk for symptomatic urinary tract infection in women with bacteriuria. Asymptomatic bacteriuria is the major risk factor for developing symptomatic UTIs during pregnancy and may be associated with adverse effects on maternal and fetal health. Because most symptomatic UTIs develop in women with bacteriuria earlier in pregnancy, treatment of bacteriuria is undertaken to prevent symptomatic infections. All pregnant women should be screened at the first antenatal visit, which is reliably and inexpensively done with a dipstick culture. Short-course therapy should be given to women with bacteriuria and clearance of bacteriuria should be documented after therapy is complete. Failure to eliminate bacteriuria with repeated therapy or recurrence with the same organism is indicative of renal parenchymal infection or a structural abnormality. All women with persistent bacteriuria or recurrent infection should have follow-up cultures and a urologic evaluation after delivery.

Lower urinary tract dysfunction in pregnancy: a review

It has long been observed that pregnancy may influence the development and course of urinary tract disorders. The physiological and anatomical changes inherent in normal pregnancy and the changing hormonal environment are generally assumed to play a role in the pathogenesis of urinary tract symptomatology. The purpose of this review is to examine the reported effect(s) of pregnancy on the lower urinary tract and to evaluate the possible role of pregnancy and delivery in lower urinary tract dysfunction.

Urinary tract infections complicating pregnancy

Urinary infections, with a spectrum from covert bacteriuria to severe pyelonephritis, commonly complicate pregnancy. Serious infections follow untreated silent bacteriuria in a fourth of cases, and routine screening can be justified in high-risk populations, particularly in those women from lower socioeconomic strata. Despite an initial salutary response to a number of antimicrobial regimens, covert bacteriuria recurs in one-third of treated women whose risk of pyelonephritis again is at 25%. Acute cystitis may be unrelated to these other infections and responds readily to a number of regimens; however, single-dose therapy is not recommended because early pyelonephritis can be mistaken for uncomplicated cystitis. Pyelonephritis is the most common severe bacterial infection complicating pregnancy. These women are frequently quite ill, and hospitalization is recommended. Since 85-90% respond within 72 h to intravenous fluids and antimicrobials, continued fever and evidence for sepsis should prompt a search for underlying obstruction. Perhaps 20% of women with severe pyelonephritis develop complications that include septic shock syndrome or its presumed variants. These latter include renal dysfunction, haemolysis and thrombocytopenia, and pulmonary capillary injury. In most of these women, continued fluid and antimicrobial therapy result in a salutary outcome, but there is occasional maternal morbidity.