Direct antimicrobial susceptibility testing for acute urinary tract infections in women.

Despite its theoretical advantages, direct antimicrobial susceptibility testing (DST) of urine specimens remains controversial largely because of concerns regarding its accuracy, particularly with mixed cultures. To evaluate the performance of DST in the setting of acute urinary tract infection (UTI), we performed DST using 25 traditional and contemporary antimicrobial agents on urine specimens from 162 women with suspected acute uncomplicated UTI, and compared these results with the results of standardized disk diffusion susceptibility tests done on the same specimens. Direct tests were interpretable for 129 specimens, i.e., 80% of all specimens and 85% of the 152 specimens that met the culture criteria for UTI. Of the 2,983 individual comparisons between the direct and standard tests, 0.8% represented very major errors, 0.6% represented major errors, 3.1% represented minor errors, and 95.5% were in agreement. Errors were more common in association with older antimicrobial agents and agents with a high prevalence of antimicrobial resistance, non-Escherichia coli strains, low urine bacterial concentrations, sparse or mixed growth in the direct test, and the presence of multiple significant organisms in urine. The urine leukocyte concentration was > or = 15/mm3 in all subjects and did not differentiate between specimens that gave an interpretable direct test and those that did not. Calculation of the sensitivity of DST in identifying antimicrobial resistance supplemented conventional error rate analysis. We conclude that when used selectively and interpreted carefully, DST of urine specimens offers an efficient, rapid, and accurate method for antimicrobial susceptibility determination for acute UTI, particularly when the urine bacterial concentration is > 10(5) CFU/ml.

Randomized comparative trial and cost analysis of 3-day antimicrobial regimens for treatment of acute cystitis in women.

OBJECTIVE: To determine the efficacy, safety, and costs associated with four different 3-day regimens for the treatment of acute uncomplicated cystitis in women. DESIGN: A prospective randomized trial with a cost analysis. STUDY POPULATION: Women with acute cystitis attending a student health center. INTERVENTIONS: Treatment with 3-day oral regimens of trimethoprim-sulfamethoxazole, 160 mg/800 mg twice daily, macrocrystalline nitrofurantoin, 100 mg four times daily, cefadroxil, 500 mg twice daily, or amoxicillin, 500 mg three times daily. RESULTS: Six weeks after treatment, 32 (82%) of 39 women treated with trimethoprim-sulfamethoxazole were cured compared with 22 (61%) of 36 treated with nitrofurantoin (P = .04 vs trimethoprim-sulfamethoxazole), 21 (66%) of 32 treated with cefadroxil (P = .11 vs trimethoprim-sulfamethoxazole), and 28 (67%) of 42 treated with amoxicillin (P = .11 vs trimethoprim-sulfamethoxazole). Persistence of significant bacteriuria was less common with trimethoprim-sulfamethoxazole (3%) and cefadroxil (0%) compared with nitrofurantoin (16%; P = .05 vs trimethoprim-sulfamethoxazole) and amoxicillin (14%; P = .11 vs trimethoprim-sulfamethoxazole). Persistence of bacteriuria was associated with amoxicillin-resistant strains in the amoxicillin group but nitrofurantoin-susceptible strains in the nitrofurantoin group. Trimethoprim-sulfamethoxazole was more successful in eradicating Escherichia coli from rectal cultures soon after therapy and from urethral and vaginal cultures at all follow-up visits compared with the other treatment regimens. Adverse effects were reported by 16 (35%) of 46 patients receiving trimethoprim-sulfamethoxazole, 18 (43%) of 42 receiving nitrofurantoin, 12 (30%) of 40 receiving cefadroxil, and 13 (25%) of 52 receiving amoxicillin. The mean costs per patient were less with trimethoprim-sulfamethoxazole ($114) and amoxicillin ($131) compared with nitrofurantoin ($155) and cefadroxil ($155). CONCLUSIONS: A 3-day regimen of trimethoprim-sulfamethoxazole is more effective and less expensive than 3-day regimens of nitrofurantoin, cefadroxil, or amoxicillin for treatment of uncomplicated cystitis in women. The increased efficacy of trimethoprim-sulfamethoxazole is likely related to its antimicrobial effects against E coli in the rectum, urethra, and vagina.

Combined use of alpha-fetoprotein and ultrasound in the prenatal diagnosis of arteriovenous fistula in the brain.

A case of arteriovenous fistula in the brain detected by the combined use of maternal serum alpha-fetoprotein (AFP) and ultrasound in the third trimester of pregnancy is described. The maternal serum AFP concentration at 34 weeks of gestation was 300 ng/mL (2.3 times the median). Stage II diagnostic ultrasonography at 37 weeks revealed a large midline cystic mass, contiguous to a normal-appearing lateral ventricle and surrounded by an abnormal heterogeneous zone of increased echogenicity. At birth, the cord blood AFP concentration was 2 SD above the mean. Subsequent histopathologic examination revealed a vein of Galen aneurysm and fistula in the brain.