Comparison of media for isolation of Ureaplasma urealyticum and genital Mycoplasma species

The demographic and behavioural profile of women with cervicitis infected with Chlamydia trachomatis, Mycoplasma hominis and Ureaplasma urealyticum and the comparison of two medical regimens

OBJECTIVE

The aim of this study was to compare the therapeutic effect of single dose oral azithromycin with twice-daily, 7-day doxycycline in women with chlamydial, mycoplasmic or ureaplasmic cervicitis and to demonstrate the demographic and behavioral profile of infected women.

MATERIALS AND METHODS

Five hundred and thirty-three women with various gynecologic complaints were recruited for this study. All women were screened for Chlamydia trachomatis (CT), Ureaplasma urealyticum (UU) and Mycoplasma hominis (MH) by enzyme immune assay tests. Patients positive for Neisseria gonorrhoeae were excluded. Women treated for these infections were tested after completing medical therapy. Educational levels of infected women were similar in each group. The prevalence of CT, UU and MH was 3.4% (18/533), 11.8% (63/533) and 0.9% (5/533), respectively. In 452 patients, no treatment was administered. The remaining patients were either treated with azithromycin (n=41) or doxycycline (n=40). The eradication rate for the infectious agents was 87.3% and 93.5% in the group of azithromycin and doxycycline, respectively (P>0.05). There was no statistically significant difference in efficacy between single dose azithromycin and a 7-day course of doxycycline with respect to the treatment of culture-positive cases. Recurrences were observed in five cases in azithromycin group (12.5%) and in three cases in doxycycline group (7.5%).

CONCLUSIONS

The treatment of uncomplicated chlamydial, mycoplasmic and ureaplasmic cervicitis with a single dose of azithromycin administered under supervision in the clinic is as effective as a 7-day course of doxycycline. This regimen may overcome the problem of compliance with the standard twice-daily, 7-day regimen of doxycycline.

Comparison of multiplex PCR assay with culture for detection of genital mycoplasmas

Ureaplasma, spp. Mycoplasma genitalium, and Mycoplasma hominis are associated with infection of the genitourinary tract, reproductive failure, and neonatal morbidity and mortality. We have developed a multiplex PCR for the detection of these Mycoplasmatales in a single amplification reaction. The analytical sensitivities of this assay were 10.8, 10.8, and 8.8 CFU for each organism, respectively. This multiplex PCR was compared to culture on 26 cervical swabs, 2 vaginal swabs, 4 female urine specimens, 49 semen samples, 2 male urine specimens, and 1 nonspecified sample. A total of 21 specimens were culture positive (25%); 17 of these were PCR positive. An additional 11 specimens were PCR positive but culture negative. Of the 21 culture-positive specimens, 17 (81%) grew Ureaplasma spp. and 4 (19%) grew Mycoplasma spp. Of the 28 PCR-positive specimens, Ureaplasma spp. was detected in 23 (82%), M. hominis was detected in 3 (11%), and both were detected in 2 (7%). In a confirmatory analysis, all samples were tested by amplification of a second target of the ureaplasma genome. True-positive cases were defined as a positive result by culture or by both amplification assays. The multiplex PCR detected organisms in 26 of the 30 true-positive specimens, as well as in 2 other specimens. Based on a 36% prevalence of infection, the sensitivity, specificity, and positive and negative predictive values of multiplex PCR analyses were 87, 96, 94, and 93%, respectively. Multiplex PCR offers a rapid, sensitive, and easy method to detect genital mycoplasmas.

High rates of genital mycoplasma infection in the highlands of Papua New Guinea determined both by culture and by a commercial detection kit

Duplicate vaginal swabs were collected from 100 women, and comparisons were made between an in-house broth-agar culture system and a commercially available kit, the Mycoplasma IST kit (bioMérieux), for the detection of Mycoplasma hominis and Ureaplasma urealyticum. There was good agreement between the two systems for detection of the genital mycoplasmas in terms of sensitivity, with values of > 92% being obtained. In terms of specificity, the mutual comparisons were less favorable, though specificity values of > 72% were obtained. Statistically there was no significant difference in the performance of the two tests (P < 0.1 for both M. hominis and U. urealyticum). While the broth-agar culture system was considerably less expensive than the kit, the Mycoplasma IST kit provided additional information on antibiotic susceptibilities and had the advantages of a shelf life of up to 12 months and not requiring the preparation of culture media. The prevalences of colonization obtained for M. hominis and U. urealyticum were extremely high in this randomly selected group of women from periurban and rural settlements in the Eastern Highlands of Papua New Guinea, being > or = 70% for M. hominis and > or = 78% for U. urealyticum. colonization with both genital mycoplasmas simultaneously was also very common, with > or = 60% of women being colonized by both M. hominis and U. urealyticum.

Frequency and significance of isolation of Ureaplasma urealyticum and Mycoplasma hominis from cerebrospinal fluid and tracheal aspirate specimens from low birth weight infants

To investigate the pathogenicity of Ureaplasma urealyticum and Mycoplasma hominis in preterm infants, we conducted a study to determine (1) frequency of isolation from cerebrospinal fluid and tracheal aspirate specimens and (2) clinical outcomes and effect of erythromycin treatment in ureaplasma-colonized infants. From the cerebrospinal fluid of 920 infants, U. urealyticum was isolated from 2 (0.2%) and M. hominis from none. From tracheal aspirate specimens from 224 infants, U. urealyticum was recovered from 37 (17%) and M. hominis from 4 (2%). Demographic characteristics and clinical outcomes were compared in very low birth weight infants (< 1500 gm) who were culture-positive or -negative for U. urealyticum. Although infants with positive results were less mature than their cohorts with negative results, there were no substantive differences in clinical outcomes between the two groups. Initiation of erythromycin treatment of infants with positive ureaplasma culture results at a mean age of 16.4 days did not appear to alter the clinical outcome. We conclude that in preterm infants (1) infection of the cerebrospinal fluid by U. urealyticum is infrequent, (2) ureaplasma organisms are frequently present in tracheal aspirate specimens but do not appear to be related to the presence or the subsequent development of respiratory disease, and (3) initiation of erythromycin treatment at 1 to 3 weeks of age does not alter the clinical course.

Comparison of commercially available media for detection and isolation of Ureaplasma urealyticum and Mycoplasma hominis

The Mycotrim Triphasic flask system (Irvine Scientific, Irvine, Calif.) was compared with a system composed of Mycotrim GU broth (Irvine Scientific) and A7 or A8 agar (Remel, Lenexa, Kans.) for the ability to detect Ureaplasma urealyticum and Mycoplasma hominis from 129 genital specimens. Of the 64 specimens positive for U. urealyticum, 25, 98, and 100% were detected on Mycotrim Triphasic agar and A7 and A8 agars, respectively. All 18 specimens that grew M. hominis were detected by A7 and A8 agars, and 94% grew on Mycotrim Triphasic agar. Mycotrim GU broth detected all of the positive specimens, and Mycotrim Triphasic broth detected all but one. Mycotrim GU broth inoculated simultaneously with either A7 or A8 agar was found to be more sensitive and cost-effective than the Mycotrim Triphasic flask system.

A study of three blood culture media for isolating genital mycoplasmas from obstetrical and gynaecological patients

Mycoplasma species are often found colonising the female genital tract. Their ability to become invasive and pathogenic, however, is often ignored, since attempts may not be made to culture these organisms from the bloodstream. We have investigated the ability of three types of blood culture media to support the growth of genital mycoplasmas. The media studied included brain-heart infusion broth, brain-heart infusion broth supplemented with 30% V/V sucrose and fastidious anaerobe broth. Genital mycoplasmas were cultured from the latter medium only. Since this was the sole medium which was liquoid-free, the inhibitory effects of liquoid on Mycoplasma spp. is discussed. This study comprised an investigation of 75 patients in obstetric and gynaecological wards with postpartum or post-operative fever. Genital mycoplasmas were isolated from five (6.7%) patients, four with Ureaplasma urealyticum and one with M. hominis. The value of considering these organisms in the differential diagnosis of fever in 'at risk' patients and of including appropriate media for their isolation is emphasised.

Isolation of Mycoplasma species and Ureaplasma urealyticum from obstetrical and gynecological patients by using commercially available medium formulations

One hundred duplicate endocervical specimens from obstetrical and gynecological patients were cultured for Mycoplasma spp. and Ureaplasma urealyticum. Rates of recovery of these organisms from commercially prepared A7 medium and the Mycotrim-GU system were compared. We detected 14 (93%) of the total 15 isolates of Mycoplasma spp. on A7 plates and 11 (73%) in the Mycotrim-GU system. We detected 34 (89%) of the total 38 isolates of U. urealyticum on A7 plates and 32 (84%) in the Mycotrim-GU system. The times of detection for both types of organism were similar in the two systems. We conclude that cultivation on A7 medium as described is a more cost-effective method of recovery of Mycoplasma spp. and U. urealyticum than the Mycotrim-GU system.

Evaluation of Mycotrim-GU for isolation of Mycoplasma species and Ureaplasma urealyticum

The Mycotrim-GU (Hana Biologics, Berkeley, Calif.) biphasic culture system and a conventional system were compared for their ability to detect Ureaplasma urealyticum and Mycoplasma species in 100 clinical specimens. Both systems detected 18 Mycoplasma spp. isolates. The average colony detection time was 1.9 days with the Mycotrim-GU and 2.3 days with the conventional system. The Mycotrim-GU agar detected all 33 U. urealyticum isolates recovered in the study, and the conventional agar detected 31. In addition to the U. urealyticum isolates recovered from the agar, there were several specimens that, although they did not grow colonies on the agar, gave an alkaline broth change. Of these specimens, two were found with the conventional system and seven were found with the Mycotrim-GU. The average detection time of U. urealyticum colonies was 2.0 days for the conventional agar and 1.7 days for the Mycotrim-GU. The Mycotrim-GU offers several advantages over the conventional system: it is commercially available, consists of a one-flask system which is ready to use, has a significantly longer shelf life, and is cost competitive. This study showed the Mycotrim-GU to be an effective system for detecting the genital mycoplasmas.