Sharon A. Poulin

Prospective Study of Chlamydia pneumoniae IgG Seropositivity and Risks of Future Myocardial Infarction

BACKGROUND Chlamydia pneumoniae has been hypothesized to play a role in atherothrombosis. However, prospective data relating exposure to Chlamydia pneumoniae and risks of future myocardial infarction (MI) are sparse. METHODS AND RESULTS In a prospective cohort of nearly 15 000 healthy men, we measured IgG antibodies directed against Chlamydia pneumoniae in blood samples collected at baseline from 343 study participants who subsequently reported a first MI and from an equal number of age- and smoking-matched control subjects who did not report vascular disease during a 12-year follow-up period. The proportion of study subjects with IgG antibodies directed against Chlamydia increased with age and cigarette consumption. However, prevalence rates of Chlamydia IgG seropositivity were virtually identical at baseline among men who subsequently reported first MI compared with age- and smoking-matched control subjects. Specifically, the relative risks of future MI associated with Chlamydia pneumoniae IgG titers >/=1:16, 1:32, 1:64, 1:128, and 1:256 were 1.1, 1.0, 1.1, 1.0, and 0.8, respectively (all probability values not significant). There was no association in analyses adjusted for other risk factors, evaluating early as compared with late events, or among nonsmokers. Further, there was no association between seropositivity and concentration of C-reactive protein, a marker of inflammation that predicts MI risk in this cohort. CONCLUSIONS In a large-scale study of socioeconomically homogeneous men that controlled for age, smoking, and other cardiovascular risk factors, we found no evidence of association between Chlamydia pneumoniae IgG seropositivity and risks of future MI.

Ureaplasma urealyticum infection of the placenta in pregnancies that ended prematurely

Objective To investigate the relationship between Ureaplasma urealyticum infection of the placenta and premature onset of labor. Methods We studied 647 pregnancies that resulted in the live birth of an infant weighing less than 1501 g. The chorionic surface of the placenta was cultured for U urealyticum, Mycoplasma hominis, and group B streptococci. Results The rate of ureaplasma isolation increased with increasing interval between rupture of membranes and delivery. When analyses were limited to the 96 singleton pregnancies that ended within 1 hour of rupture of membranes and before the 29th week of gestation, U urealyticum was prominently associated with an increased risk of premature onset of labor (P = .008 unadjusted, and P = .05 when adjustment was made for all potential confounders). Ureaplasma infection rate was lowest in pregnancies terminated because of severe maternal preeclampsia or progressive fetal growth restriction. Conclusion Ureaplasma ureaplasma urealyticum infection is associated with premature onset of labor and with increasing duration of time between rupture of membranes and delivery. Eradication of ureaplasmas from the urogental tract of women and their partners, ideally before conception, should be considered.

In vitro antimicrobial activity of rosoxacin against Neisseria gonorrhoeae, Chlamydia trachomatis, and Ureaplasma urealyticum.

The antimicrobial activity of rosoxacin, a new quinoline antibacterial compound, was determined against the causative organisms of three sexually transmitted diseases. Rosoxacin demonstrated a high degree of activity against Neisseria gonorrhoeae clinical isolates, with the minimal inhibitory concentrations for 50% of these being 0.03 microgram/ml. The corresponding minimal inhibitory concentrations for penicillin, ampicillin, tetracycline, and spectinomycin were 0.25 U/ml, 0.125 microgram/ml, 0.25 microgram/ml, and 16 microgram/ml, respectively. Eleven strains of Chlamydia trachomatis were inhibited by 5 microgram of rosoxacin per ml, and each of seven Ureaplasma urealyticum strains was inhibited by 2 to 8 microgram of rosoxacin per ml. The results of these susceptibility studies, coupled with those of an earlier evaluation of the pharmacokinetics of rosoxacin, provide support for extending or undertaking clinical evaluations of this compound against infections with N. gonorrhoeae, C. trachomatis, and U. urealyticum.

Laboratory Diagnosis of Genital Mycoplasma Infection

The controversy regarding the association of Ureaplasma urealyticum and Mycoplasma horninis with human reproductive wastage and genitourinary tract infection is due to the many different techniques and media used in different laboratories. Expertise definitely influences the rate of recovery. In our laboratory which processes over 5000 specimens for mycoplasmas a year, we have encountered specific problems that have shown that the mycoplasmas, particularly the ureaplasmas, differ greatly from bacteria and viruses. Their isolation and cultivation requirements are also quite different. The patients are referred to our laboratory by gynecologists and obstetricians for problems of infertility or reproductive wastage. A few come solely for genitourinary tract infections. The types of specimens that are usually sent to the laboratory together with the rate of genital mycoplasma isolation from these different specimens are shown in TABLES 1 and 2. Specimens from 3165 patients, 2605 women and 5 6 0 men, are described. These isolations were made from June 1986 to March 1987. The difference in the isolations from the urine of men and women is highly statistically significant (chi square 48.7, p= <O.ooOOl). Also highly significant is the difference in the isolations from the cervix and the male urethra (chi square 18.8, p=O.ooOOl). The isolations from women far exceed those from men. What is particularly noteworthy is that in women the ureaplasmas reflect what appears to be an ascending infection, with the highest isolation rate from the vagina and decreasing isolation rate from the cervix, and the lowest rate from the endometrial biopsy. In males, the isolation of ureaplasmas appears to be the same from the semen, the urethra, and the urine. M. horninis is found more frequently in the cervix in women and in the urethra in males. It is often stated that because the ureaplasmas are so frequently isolated from the vagina, they cannot be pathogens. Consider the case of Escherichia coli which we all harbor in our gut, yet they are the most frequent isolate in urinary tract infections. Our referring physicians are encouraged to send two specimens for each patient. We have found that occasionally an isolation can be missed when only one specimen is sent. Thus we found disagreement in 156 (5%) patients of the 3165. One hundred two urines were positive while swabs were negative, and conversely 54 swabs were positive while urines were negative. Five percent of patients would have received incorrect laboratory results with only one specimen. Five methods of incubation were compared for efficacy in isolations, air, both unsealed and sealed with paraffin, anaerobic and CO, (both Biobag, Marion Scientific), and the Fortner method utilizing Serratia marcescens, a method used by Dr. Louis

ureaplasma urealyticum In Young Children With Acute Respiratory Symptoms

Eighty-eight children ranging in age from 2 to 64 months were seen in a pediatric practice for acute pulmonary symptoms, such as wheezing, cough, bronchiolitis, and respiratory distress. Throat cultures were performed for Ureaplasma urealyticum and Mycoplasma hominis. U. urealyticum was isolated from 29 (33%). Of the 54 infants 12 months or younger, 19 (35%) were positive for U. urealyticum. Of 21 children between 1 and 2 years of age, 9 (43%) had U. urealyticum in the throat. One (14%) of seven was positive at 2 to 3 years. Six children older than 3 years were negative. Only one child had M. hominis as well as U. urealyticum. Cultures of 22 age-matched asymptomatic children resulted in one isolation of U. urealyticum (P < .01). This article documents the presence of U. urealyticum in the respiratory tract of children with severe respiratory symptoms up to the age of 3 years. Eradication of U. urealyticum led to clinical improvement.

DOES COLONIZATION WITH U. UREALYTICUM INCREASE WHEEZING? ▴ 1002

Of asthmatic adults, 30% have been shown to have presented with symptoms in the first year of life. The most severely bronchospastic infants are most likely to wheeze lifelong. We investigated whether there is an association between colonization with Ureaplasma urealyticum (U.u.) and wheezing in the first 3 yr. Methods: 80 children ages 2 to 36 mo. presenting with wheezing to a pediatric practice or neonatal follow-up service had throat cultures for mycoplasmas and ureaplasmas, as did 22 well controls from the same populations. Positive infants were treated with clarithromycin 15 mg/kg day for 14 days. 24 had follow-up cultures to date. Clinical course was assessed by examination and review of medical records. Results:U. u. was isolated in 35% of subjects, and 4.5% of controls(p<.01). Isolations were more frequent in infants <12 mo. Positive subjects did not differ from other groups in gestational age, but had significantly more wheezing in the 1st year (mean 51da., p<.01) than negative subjects (7 da.) or controls (3 da.), and had more prior courses of antibiotics than negative subjects (p<.02). After treatment 22 had negative cultures, and improvement in their symptoms. Conclusions: Colonization with U. urealyticum increases the severity of wheezing in the first year. Its eradication may have promise for improving long term asthma symptoms. Some cultures funded by Abbott Laboratories.

Ureaplasma urealyticum: Subcultures invalid for antibiotic susceptibility tests

We tested the antibiotic susceptibilities of 100 Ureaplasma urealyticum strains from 99 patients using a broth-disk method and two types of inocula: urine sediments and overnight broth subcultures of the sediments. Of the 100 ureaplasma-positive urine sediments tested, nine (9%) of the ureaplasmas were found resistant to all four tetracyclines. When overnight broth cultures were used as the inoculum, 54 (54%) were found to be resistant to all four tetracyclines, an increase in resistance of 45 (45%). Thirty-seven susceptible strains remained susceptible upon subculture. The nine resistant strains remained resistant. Loss of susceptibility was not related to the pH or titer of ureaplasmas in the urine sediment inoculum but was related to the pH and titers when subcultures were used as the inoculum. Results of cultures following treatment, available for 53 patients, showed that treatment successes and treatment failures were significantly related to antibiotic susceptibility tests done with urine sediments but not to those done with broth subcultures as the inocula. Because reliable susceptibility testing is essential for appropriate therapy for U. urealyticum infections, all factors influencing this test need to be recognized and defined.