Treatment Of Mycoplasma Infections Research Articles

Mechanisms of Long-Term Persistence of Mycoplasmas in Children with Asthma.

Improving the management of children with asthma associated with mycoplasma infection is important. Aim: To study the duration of the persistence of antigens, and DNA in a free state, in the structures of circulating immune complexes (CICs) and living cells of Mycoplasma pneumoniae (Mpn) and Mycoplasma hominis (Mh) in children with asthma. In total, 205 children with asthma from 1 to 14 years were observed. The reaction of aggregate-hemagglutination (AHAA), the direct immunofluorescence reaction (DIF), the reaction of the polymerase chain reaction (PCR), and the culture method were used. In addition, 47 children were re-examined 1.5 months after the treatment of mycoplasma infection with azithromycin. The number of samples positive for antigens and DNA in the free state and in the structures of CICs significantly decreased. Then, 50 blood serum samples containing Mh antigens, and 50 samples containing Mpn antigens were analyzed by culture method. Mh was isolated in 21 (65.5%) of 32 samples containing DNA. Mpn was isolated from antigen-positive samples in nine cases. The presented data indicate the long-term persistence of antigens, and DNA of mycoplasma cells in the free state, in the structure of CICs, as well as in the form of "microcolonies". A high level of CICs can be used to predict the course of the disease and the response to therapy.

Interactive Effect between Florfenicol and Tylosin Tartrate for Use in the Therapy and Prevention of Diseases in Veterinary Medicine

An in vitro test on the pharmacological interaction of the antibiotic combination between florfenicol and tylosin tartrate was performed. An in vitro challenge method was used for this purpose. The results were used to calculate their interaction using the graphical representation known as ISOBOLOGRAM. The pure salts of florfenicol and tylosin tartrate were used. The agar bioassay method was used. The following criteria were used to quantify the results: A synergistic effect was defined when the actual/theoretical effect (SMEF) was greater than 1. The additive effect was defined when the SMEF was equal to 1. The area between antagonism and additive effect was defined as the zone of indifference. When studying the interaction between florfenicol and tylosin tartrate it was observed that the best SMF of this antibiotic combination was 1.45 when the concentration ratio between the antibiotics was 1 : 4 (florfenicol tylosin tartrate respectively). Consequently, it can be postulated that the combination of florfenicol with tylosin tartrate showed a synergistic effect and can be recommended in poultry and swine for the treatment of mycoplasma infections, most gram + and gram- germs and other infectious agents sensitive to the formulation.

The Interactive Effect between Kitasamycin Tartrate and Doxycycline Hydrate for Use in the Therapy and Prevention of Diseases in Veterinary Medicine

An in vitro test on the pharmacological interaction of the antibiotic combination between kitasamycin tartrate and Doxycycline hydrate was carried out. An in vitro challenge method was used for this purpose. The results were used to calculate their interaction using the graphical representation known as ISOBOLOGRAM. The pure salts of Kitasamycin tartrap and Doxycycline Hydrate were used and were obtained from the manufacturer of the product, Lapi - Doxi. The agar bioassay method was used. The following criteria were used to quantify the results: A synergistic effect was defined when the actual/theoretical effect (SMEF) was greater than 1. The additive effect was defined when the SMEF was equal to 1. The area between the antagonism and additive effect was defined as the zone of indifference. When studying the interaction between florfenicol and tylosin tartrate it was observed that the best SMF of this antibiotic combination was 1.45 when the concentration ratio between the antibiotics was 1 : 4 (Kitasamycin tartrate and doxycycline hydrate respectively). Consequently it can be postulated that the combination of kitasamycin tartrate with doxycycline hydrate showed a synergistic effect and can be recommended in poultry and swine for the treatment of mycoplasma infections, most gram + and gram- germs and other infectious agents sensitive to the formulation.

Control tactics and evaluation of clinical efficacy of therapy in children with bronchial asthma associated with mycoplasma infection

The uncontrolled course of bronchial asthma (BA) in children and insufficient efficacy of standard therapy regimens may be due to underestimated infectious factors. The objective: to study specific parameters of the course and treatment of mycoplasma infection, improve monitoring over BA therapy in children of the tender and preschool age. Subjects and methods. 320 children with BA in the age from 1 to 7 years old were followed up. In this work, Mycoplasma pneumoniae (FH), Mycoplasma hominis (H-34), Ureaplasma urealyticum (serotype 8), Mycoplasma fermentans (PG18) and Mycoplasma arthritidis (PG6) were used, they were cultured on a liquid medium for cultivation of mycoplasmas and ureaplasmas. To isolate CIC from blood serum samples, we used the method of precipitation with 3.5% polyethylene glycol (PEG, 6000 Da), hemagglutination assays and IFA were used to identify mycoplasma antigens, mycoplasma DNA was detected by PCR with InterLabService diagnostic kits. The data of 47 patients with prolonged mycoplasma antigenemia were assessed at the baseline and in 1.5-3 months after the treatment course of azithromycin.Results. 320 blood serum samples from children with BA were tested, and the detection rate by hemagglutination assays of M. pneumoniae antigens was 60.9%, M. hominis – 43.4%, U. urealyticum – 44.8%, M. arthritidis – 29.7%, M. fermentrans – 45.3%. The assessment of relationship between of M. pneumoniae, M. hominis and asthma exacerbation showed that antigens of M. pneumoniae and M. hominis were found in 216 children (single or associated). After treatment with azithromycin, the frequency of BA exacerbations within 3 months decreased by 2.4 times, as well as there was a reduction in the number of samples positive for antigens and DNA of mycoplasma in a free state and within CIC. The persistence of antigens, DNA of M. pneumoniae and M. hominis before treatment of 47 children was 80.9 and 66.0% of cases, after treatment with azithromycin – 31.9 and 25.5% of cases, respectively (p < 0.001). Within CIC isolated from the blood serum of patients, antigens to M. pneumoniae and M. hominis before treatment were detected by IFA in 63.8 and 70.2% of children, after treatment – in 31.9 and 23.4%, respectively. p < 0.001. In blood samples, DNA of M. pneumoniae and M. hominis was detected by PCR before treatment in 8.5 and 34.0%; after treatment in 6.4% (p = 0.318) and 19.1% of cases, respectively (p = 0.009), and within CIC isolated from blood serum, in 27.7 and 48.9% of cases before treatment and 8.5 and 34.0% after it, respectively (p = 0.009).

Determination of Contagious Agalactia in Sheep and Goats and Investigation of Antibiotic Susceptibility of Mycoplasma spp. Positive Isolates

Antibiotic resistance is one of the most important issues encountered globally in managing infectious diseases and is a potential problem in the treatment of Mycoplasma infections. The aims of this study were to: determine carrier rates in sick and healthy herds of sheep and goats; determine the presence in herds of carrier animals that were clinically asymptomatic for contagious agalactia and use antibiogram tests to investigate the susceptibility to antibiotics of Mycoplasma spp. positive isolates derived from sheep and goat ear swabs. The presence of contagious agalactia was diagnosed by analyzing ear swabs (n = 300, bacterial method, Mycoplasma spp.) and blood serum samples (n = 300, serological method [ELISA], Mycoplasma agalactiae) taken from sheep and goat herds located in Elazýð and Malatya provinces in eastern Turkey. The ELISA tests revealed seropositivity in 10 (3.33%) of 300 samples. In order to determine the most effective antibiotic for disease treatment, antibiogram testing was performed on 87 (29%) positive isolates that had been isolated from swab cultures. We determined tulathromycin (MIC 16 µg/mL) and tiamulin (MIC 16 µg/mL) to be the most effective antibiotics, whereas disease agents were resistant to trimethoprim/sulfamethoxazole and neomycin.

STUDY on the gender prevalence and sensitivity of urogenital mycoplasmas to antibiotics in YAOUNDE, CAMEROON

ABSTRACT Urogenital mycoplasmas are bacteria that cause genito-urinary tract infections that may be initially asymptomatic but can progress and lead to severe complications and threaten reproductive health (vaginosis, salpingitis urethritis). The inadequate antibiotic treatment of mycoplasma infections has led to the emergence and spread of resistant strains. Moreover, non-adherence to treatment, self-medication and untargeted therapy are contributing factors to resistance. In spite of these notions, there is limited documentation of resistance to urogenital mycoplasmas in Cameroon. We therefore aimed to determine the prevalence of urogenital mycoplasma infections and their susceptibility to antibiotics both in males and females. To initiate this work, Questionnaires were administered to 126 persons suspected with urogenital mycoplasma at the GTAB (Group of Biomedical Analysis Technicians) laboratory Yaounde. Urethral and endocervical specimens were collected from each person. The detection and sensitivities of urogenital mycoplasmas to macrolides, doxycycline and fluoroquinolones were performed with the Mycofast Evolution 3 kit (EliTech Microbio). Overall, 74 (58.73%) of patients were positive for urogenital mycoplasma. Amongst these, 4/74 (5.40%) were infected with Mycoplasma hominis, 14/74 (18.9%) had Ureaplasma urealyticum and 56 / 74(75.70%) were co-infected with both Mycoplasma hominis and U. urealyticum. Females had more genital mycoplasma infection 66/74(89.2%) compared to males 8/74(10.8%). This difference was however not significant (p = 0.64). Singles had a statistically higher prevalence of 71.62% than in the other groups (married, divorced, widowed) (p˂0.0001). U. urealyticum had a sensitivity of 100% to pristinamycin and Josamycin. Mycoplasma hominis was 100% sensitive to Doxycycline, Pristinamycin and Josamycin. The resistance rate U. urealyticum was 85.7% with Ciprofloxacin. All Mycoplasma hominis were 100% resistant to Azithromycin and Roxythromycin. Cases of co-infection (Mycoplasma hominis+ U. urealyticum) depicted a decline in the sensitivity to 53.6%, 78.6% and 75.0% respectively to Doxycycline, Pristinamycin and Josamycin. Only Pristinamycin and Josamycin remained effective for the treatment of urogenital mycoplasma infections.

Diagnosis and treatment of Neisseria gonorrhoeae, Chlamydia trachomatis and Mycoplasma infections in female genital tract

Neisseria gonorrhoeae, Chlamydia trachomatis and Mycoplasma are common in female genital tract infections, which are associated with urethritis, cervicitis, pelvic inflammatory disease, ectopic pregnancy, infertility, chronic pelvic pain and perinatal infections. They can cause the infectious diseases asymptomatically, which would be easily neglected. Nucleic acid amplification test (NAAT) can provide an accurate diagnosis for these diseases, and qualified laboratories should be suggested to develop the project. Appropriate sensitive antibiotics and sex partners participation are essential for treatment. Noticeably, asymptomatic carrier should be differentiated during the treatment of Mycoplasma infections. It should increase awareness of these infectious diseases, in order to reduce the harm caused by misdiagnosis.(Chin J Lab Med, 2018, 41: 263-266) Key words: Genital diseases, female; Gonorrhea; Chlamydia infections; Mycoplasma infections

120 cases of non gonococcal urethritis mycoplasma and chlamydia infection and drug resistance status

Objective To investigate non gonococcal urethritis mycoplasma and chlamydia infection and drug sensitivity status. Methods From June 2014 to December 2014, 120 cases of non gonococcal urethritis patients in our hospital were given chlamydia trachomatis, ureaplasma, mycoplasma detection and mycoplasma culture and drug sensitivity test of mycoplasma.Mycoplasma and chlamydia test results were compared between male and female patients.Positive drug sensitivity test results of ureaplasma urealyticum(Uu) and mycoplasma hominis(Mh) were observed. Results Among the 120 patients with positive detection, the proportion of Uu was the highest, up to 41.67% (50/120); the second was Mh, accounting for 31.67% (38/120). The detection rate of Uu in women (57.14%) was significantly higher than that in males (28.13%), and the difference was statistically significant (χ2=10.35, P<0.05). The susceptibility of mycoplasma to pristinamycin susceptible rate highest, Uu and type mycoplasma reached 100.00%; followed by doxycycline, the susceptibility of Uu reached 98.00% and the susceptibility of Mh to 100.00%; sensitive rates of Uu and Mh to josamycin were 96.00% and 90.48%.The sensitive rates of Uu and Mh to tetracycline were 92.00% and 90.48% respectively. Conclusion The mycoplasma infection was mainly caused by Uu.Clinical treatment of mycoplasma infection can be based on the drug sensitivity test results to reasonably choose antibiotics, and sensitive rates of pristinamycin, doxycycline were higher. Key words: Non gonococcal urethritis; Mycoplasma; Chlamydia pneumoniae; Infection; Drug sensitivity

MYCOPLASMA INFECTIONS IN HUMANS

Summary Members of the genus Mycoplasma are parasitic bacteria that are widespread in nature. Several Mycoplasma species are important causative agents of various infections of mucosal surfaces in humans, especially in the urogenital or respiratory tracts. Pathogenetic mechanisms of mycoplasmas are intensively studied. The “gold” standard of mycoplasma detection is cultivation, which is very difficult and time-consuming. The other options for identifying mycoplasmas include direct antigen detection or molecular-biology methods, such as polymerase chain reaction, DNA-hybridization and sequencing. Mycoplasmas are naturally resistant to beta-lactam antibiotics because of lack of cell wall. Tetracyclines or fluoroquinolones are regarded as the first choice in the treatment of mycoplasma infections. Several reports have documented resistance of mycoplasmas to macrolides worldwide. This report summarizes our current knowledge of laboratory diagnosis and treatment of mycoplasma infections.

MYCOPLASMA AS THE CAUSE OF INFECTIONS IN CATTLE

During the last few years more than 20 different types of Mycoplasma, Ureaplasma and Acholeplasma microorganisms have been isolated from cattle with different clinical signs. Most of Mycoplasma microorganisms have a secondary role in the appearance of infection in cattle. Differently, Mycoplasma bovis (M. bovis) has a primary role in the infection of cattle. It has been proved that M. bovis frequently causes pneumonia, mastitis and arthritis in cows. Besides, M. bovis is identified as a causative agent in meningitis, middle ear infection, keratoconjunctivitis, decubitus abscesses, vaginitis and miscarriages in cows. Diagnostic was done based on the clinical signs and detection of the causative agent, in individual animals and in the herds as whole. The methods used for diagnostic can be cultivation of the causative agent or fluorescence test for antigen detection in pathological material. Also, the detection of specific antibodies can be done, applying different serological methods: fast agglutination on a plate, indirect hemiinhibition, agar gel immunodifussion, CF, ELISA, etc. Polymerasa chain reaction (PCR) is a sensitive method which is mostly used for confirmatory etiological diagnostic. The treatment of Mycoplasma infection is very demanding due to the resistance to most frequently used antibiotics and therefore very different from treating any other bacterial infection. M. bovis is one of the most complicated agents for control as its response to the treatment is weak. A good program for eradication of mycoplasmosis is based on early carrier detection and they are excluded the herds.

Improvement of control methods of treatment of mycoplasma infection in children with bronchial asthma

Background. Improvement of control methods of treatment of mycoplasma infection in children with bronchial asthma. Methods. 52 children from 1 to 4 years old with bronchial asthma who had mycoplasma antigens in the blood were examined before treatment of mycoplasma infection, 15 patients were examined in 1,5 months after treatment. Reaction of aggregate-hemagglutination, immunofluorescence assay and the reaction of the polymerase chain reaction (PCR) were used for detection of mycoplasmas’ antigens and DNA. Results. In reaction of aggregate-hemagglutination Mycoplasma pneumoniae (Mpn) was detected in 65,4% of patients, Mycoplasma hominis (Mh) — in 32,7%, Ureaplasma urealyticum — in 50%, Mycoplasma arthritidis — in 46,2%, Mycoplasma fermentrans — in 46,2%. In more detail, we investigated Mpn and Mh. Antigens of Mpn and Mh were detected in serum significantly frequently than DNA by PCR. DNA in structure of circulating immune complexes (CIC) was detected more often than in free state. After treatment by azithromycin the number of positive tests on antigens and DNA in free state and in structure of CIC decreased. In most cases DNA found in serum of blood in free state and in structure of CIC belongs to persistent living cells of mycoplasma. Conclusion. Empowering diagnosis of mycoplasma infections in asthma in children allows to base a comprehensive approach to laboratory diagnosis, monitor treatment, predict disease course.

In Vitro Activity of a New Quinoline Derivative, ER-2, against Clinical Isolates of Mycoplasma pneumoniae and Mycoplasma hominis

ER-2 is a new investigational quinoline derivative with the formula 7a,13b-8,8-dimethylpyrrolo[2,3-d]pyrimidine-[2,1-a]pyrrolo[4,3:2,3]-7a,8,13,13b-tetrahydroquinoline 7 (compound 7), synthesized by Department of Organic Chemistry, University of Chennai, Chennai, India (Fig. ​(Fig.1).1). This drug has shown significant activity against gram-positive and gram-negative organisms (7). FIG. 1. Chemical structure of ER-2. Mycoplasma pneumoniae is a significant cause of upper and lower respiratory tract infections in persons of all age groups (6, 8-10). In this study, we compared the in vitro antibacterial activity of ER-2 against a collection of mycoplasma species known to cause disease in humans to those of antimicrobial agents known to have in vitro activity against these organisms. Sixty-one M. pneumoniae isolates tested were collected from clinical specimens of persons with pneumonia. Forty M. hominis isolates were derived from clinical specimens from the urogenital tract. Ten of the isolates were resistant to tetracycline (MIC90, ≥8 μg/ml). Moxifloxacin, ciprofloxacin, levofloxacin, gatifloxacin, gemifloxacin, azithromycin, doxycycline, tetracycline, and clindamycin were purchased from Sigma Aldrich (St. Louis, MO). Azithromycin was tested only against M. pneumoniae since Mycoplasma hominis is mostly resistant to macrolides (9), except for the 16-member ring of this class, and clindamycin was tested only against M. hominis since it is not recommended for the treatment of M. pneumoniae (2). Antimicrobial powders were used according to the manufacturer's protocol. Working dilutions of the drugs were prepared fresh on the day of the assay. Mycoplasmas were tested by the agar dilution method using a Steers replicator as described previously (4, 5). M. pneumoniae ATCC 29342 and M. hominis ATCC 43521 were used as reference strains. Five isolates of M. pneumoniae were randomly chosen for further testing to determine minimum bactericidal concentrations (MBCs) according to the protocol previously described (9). MICs of ER-2 and other antimicrobial agents are shown in Table ​Table1.1. ER-2 exhibited excellent in vitro activity against 61 isolates of M. pneumoniae (MIC50, 0.001 μg/ml; MIC90, 0.016 μg/ml), which was the same as that of azithromycin (MIC50, 0.001 μg/ml; MIC90, 0.016 μg/ml) and which had the lowest MIC of any drug tested. Moxifloxacin (MIC50, 0.001 μg/ml; MIC90, 0.12 μg/ml) was more active than levofloxacin (MIC50, 1 μg/ml; MIC90, 1 μg/ml), ciprofloxacin (MIC50, 4 μg/ml; MIC90, 4 μg/ml), gatifloxacin (MIC50, 0.125 μg/ml; MIC90, 0.125 μg/ml), gemifloxacin (MIC50, 0.032 μg/ml; MIC90, 0.125 μg/ml), and doxycycline (MIC50, 0.25 μg/ml; MIC90, 0.25 μg/ml). MBCs of ER-2 (MBC50, 0.001 μg/ml; MBC90, 0.016 μg/ml) and moxifloxacin (MBC50, 0.06 μg/ml; MBC90, 0.12 μg/ml) showed that they were bactericidal against all of the M. pneumoniae isolates tested. TABLE 1. Susceptibilities of M. pneumoniae and M. hominis to ER-2 and other antimicrobial agents M. hominis was highly susceptible to ER-2 (MIC90, 0.06 μg/ml) and had the same susceptibility to moxifloxacin (Table ​(Table1).1). ER-2 was more highly active than gatifloxacin (MIC90, 0.125 μg/ml), clindamycin (MIC90, 0.032 μg/ml), levofloxacin (MIC90, 0.5 μg/ml), and ciprofloxacin (MIC90, 1 μg/ml). In vitro data indicate that ER-2 may have considerable promise for both genital and respiratory infections with mycoplasmas, but its clinical utility will depend upon its toxicity and pharmacokinetics (3). Our study indicates that ER-2 is active in vitro against mycoplasmal species that are clinically important in humans, with activity that was comparable to that of azithromycin and superior to those of the fluoroquinolones tested. Earlier work demonstrated that ER-2 inhibited gyrase supercoiling with potency similar to ciprofloxacin (7). Pyrimidine as a motif is found to be present in a variety of therapeutic molecules exhibiting antibacterial, antiviral, anticancer and anti-inflammatory properties (1). ER-2 consists of a uracil moiety that might be responsible for the potent activity of the compound (1). Overall, the excellent in vitro and in vivo activities of ER-2 suggest its usefulness in the treatment of mycoplasma infections. Further study for the potential use of this drug is needed.

Production and identification of monoclonal antibodies against six different Mycoplasmas

目的 制备针对临床常见的六种支原体的特异性单克隆抗体,为临床支原体感染检测提供工具.方法用灭活的支原体颗粒免疫BALB/c小鼠,通过传统杂交瘤技术制备抗支原体单克隆抗体,采用6种支原体蛋白以酶联免疫吸附试验(ELISA)进行交叉筛选,并用免疫印记法(WB)对其特异性进行鉴定.结果获得针对生殖支原体、梨形支原体、猪鼻支原体、发酵支原体、肺炎支原体、穿透支原体的特异性单克隆抗体各1株,经ELISA检测证实具有较好的反应特异性,其中,单抗Mg 6H1、Mpri ZW1和 Mpe 6G4在WB 中也同时分别与生殖支原体、梨形支原体和穿透支原体呈特异反应.结论获得针对6种人体常见感染支原体的不同单克隆抗体,它们在ELISA检测中具较好的反应特异性,有望应用于支原体感染检测。

Treatment of Mycoplasma Infections: Susceptibility of Field Isolates and Outcome of Treatment

A number of Mycoplasma species cause disease in cattle including Mycoplasma niycoides subspecies mycoides small colony type, the cause of the OIE list A disease, contagious bovine pleuropneumonia in Africa, and Mycoplasma bovis, one of the biggest causes of calf pneumonia world-wide. Symptoms include pneumonia, mastitis and arthritis, all of which adversely affect the economics of farming. Control of M. bovis is difficult because it has systems for evading the immune system and has developed resistance to a number of antimicrobials. While strategies can be deployed on the farm to reduce or possibly eliminate disease caused by M. bovis, these approaches can be time consuming, and costly in terms of drug treatment and testing, with no guarantees of success. Although some vaccine trials have seen an exacerbation of disease, vaccines are being developed, and some are in use in the USA, although data on their efficacy is sparse.

Induced expression of the antimicrobial peptide melittin inhibits experimental infection by Mycoplasma gallisepticum in chickens

The in vivo action of the antimicrobial peptide melittin, expressed from a recombinant plasmid vector, on chickens experimentally infected with Mycoplasma gallisepticum was studied. The plasmid vector pBI/mel2/rtTA includes the melittin gene under the control of an inducible tetracycline-dependent human cytomegalovirus promoter and the gene coding for the trans-activation protein rtTA. Aerosol administration of the vector, followed by infecting the chickens with M. gallisepticum 1226, is shown to inhibit development of infection. The inhibitory action was confirmed by a complex of clinical, pathomorphological, histological and serological studies, and also by comparing the M. gallisepticum reisolation frequency from the respiratory tract and internal organs. The data suggest that plasmid vectors expressing genes of antimicrobial peptides can be considered as potential agents for the prevention and treatment of mycoplasma infections in poultry farming.

Induced expression of the antimicrobial peptide melittin inhibits experimental infection by Mycoplasma gallisepticum in chickens

The in vivo action of the antimicrobial peptide melittin, expressed from a recombinant plasmid vector, on chickens experimentally infected with Mycoplasma gallisepticum was studied. The plasmid vector pBI/mel2/rtTA includes the melittin gene under the control of an inducible tetracycline-dependent human cytomegalovirus promoter and the gene coding for the trans-activation protein rtTA. Aerosol administration of the vector, followed by infecting the chickens with M. gallisepticum 1226, is shown to inhibit development of infection. The inhibitory action was confirmed by a complex of clinical, pathomorphological, histological and serological studies, and also by comparing the M. gallisepticum reisolation frequency from the respiratory tract and internal organs. The data suggest that plasmid vectors expressing genes of antimicrobial peptides can be considered as potential agents for the prevention and treatment of mycoplasma infections in poultry farming.

Efficacy of antibiotic therapy in preventing spontaneous pregnancy loss among couples colonized with genital mycoplasmas

Evidence suggests that genital mycoplasmas play a role in spontaneous abortion, prematurity, and perinatal morbidity and mortality rate. Since these organisms are sensitive to antibiotics, three treatment regimens were assessed for efficacy in preventing spontaneous pregnancy loss. The pregnancy loss rate was significantly reduced from 96% to 47.4% among those treated with doxycycline prior to conception and to less than 20% among those treated with erythromycin stearate only during pregnancy or with both regimens. The reduction in pregnancy loss rate was independent of maternal age, the number of previous abortions, gestational age at abortion, or other minor abnormalities. Diagnosis and treatment of mycoplasma infection following a first or later pregnancy loss equally prevented spontaneous loss in the next pregnancy. These observations suggest that appropriate treatment of mycoplasma infection could also prevent recurrent spontaneous abortion syndrome in couples with positive cultures.