Detection of Mycoplasma Contamination in Transplanted Retinal Cells by Rapid and Sensitive Polymerase Chain Reaction Test

Contamination of cells/tissues by infectious pathogens (e.g., fungi, viruses, or bacteria, including mycoplasma) is a major problem in cell-based transplantation. In this study, we tested a polymerase chain reaction (PCR) method to provide rapid, simple, and sensitive detection of mycoplasma contamination in laboratory cultures for clinical use. This mycoplasma PCR system covers the Mycoplasma species (spp.) listed for testing in the 17th revision of the Japanese Pharmacopoeia, and we designed it for use in transplantable retinal cells. Here, we analyzed mycoplasma contamination in induced pluripotent stem cell (iPS cell)-derived transplantable retinal pigment epithelium (RPE) cells. In the spike tests to RPE cells with nine species of class Mollicutes bacteria, including seven Mycoplasma spp. and one of each Acholeplasma spp. and Ureaplasma spp., contamination at the concentration of 100 and 10 CFU/mL were detected with 100% probability in all cases, while 1 CFU/mL had a detection rate of 0–75%. DNA prepared from bacteria species other than class Mollicutes species was not detectable, indicating the specificity of this PCR. While iPS cells and iPS-RPE cells established in our laboratory were all negative by this PCR, some of the commercially available cell lines were positive. Cells for transplantation should never have infection, as once pathogens are implanted into the eyes, they can cause severe intraocular inflammation. Thus, it is imperative to monitor for infections in the transplants, although generally, mycoplasma infection is difficult to detect.

Detection of microbial cell-free DNA in maternal and umbilical cord plasma in patients with chorioamnionitis using next generation sequencing

Background

Chorioamnionitis has been linked to spontaneous preterm labor and complications such as neonatal sepsis. We hypothesized that microbial cell-free (cf) DNA would be detectable in maternal plasma in patients with chorioamnionitis and could be the basis for a non-invasive method to detect fetal exposure to microorganisms.

Objective

The purpose of this study was to determine whether next generation sequencing could detect microbial cfDNA in maternal plasma in patients with chorioamnionitis.

Study design

Maternal plasma (n = 94) and umbilical cord plasma (n = 120) were collected during delivery at gestational age 28–41 weeks. cfDNA was extracted and sequenced. Umbilical cord plasma samples with evidence of contamination were excluded. The prevalence of microorganisms previously implicated in choriomanionitis, neonatal sepsis and intra-amniotic infections, as described in the literature, were examined to determine if there was enrichment of these microorganisms in this cohort. Specific microbial cfDNA associated with chorioamnionitis was first detected in umbilical cord plasma and confirmed in the matched maternal plasma samples (n = 77 matched pairs) among 14 cases of histologically confirmed chorioamnionitis and one case of clinical chorioamnionitis; 63 paired samples were used as controls. A correlation of rank of a given microorganism across maternal plasma and matched umbilical cord plasma was used to assess whether signals found in umbilical cord plasma were also present in maternal plasma.

Results

Microbial DNA sequences associated with clinical and/or histological chorioamnionitis were enriched in maternal plasma in cases with suspected chorioamnionitis when compared to controls (12/14 microorganisms, p = 0.02). Analysis of the microbial cfDNA in umbilical cord plasma among the 1,251 microorganisms detectable with this assay identified Streptococcus mitis, Ureaplasma spp., and Mycoplasma spp. in cases of suspected chorioamnionitis. This assay also detected cfDNA from Lactobacillus spp. in controls. Comparison between maternal plasma and umbilical cord plasma confirmed these signatures were also present in maternal plasma. Unbiased analysis of microorganisms with significantly correlated signal between matched maternal plasma and umbilical cord plasma identified the above listed 3 microorganisms, all of which have previously been implicated in patients with chorioamnionitis (Mycoplasma hominis p = 0.0001; Ureaplasma parvum p = 0.002; Streptococcus mitis p = 0.007). These data show that the pathogen signal relevant for chorioamnionitis can be identified in both maternal and umbilical cord plasma.

Conclusion

This is the first report showing the detection of relevant microbial cell-free cfDNA in maternal plasma and umbilical cord plasma in patients with clinical and/or histological chorioamnionitis. These results may lead to the development of a specific assay to detect perinatal infections for targeted therapy to reduce early neonatal sepsis complications.

Surveillance for incidence and etiology of early-onset neonatal sepsis in Soweto, South Africa

BACKGROUND

Globally, over 400,000 neonatal deaths in 2015 were attributed to sepsis, however, the incidence and etiologies of these infections are largely unknown in low-middle income countries. We aimed to determine incidence and etiology of community-acquired early-onset (<72 hours age) sepsis (EOS) using culture and molecular diagnostics.

METHODS

This was a prospective observational study, in which we conducted a surveillance for pathogens using a combination of blood culture and a polymerase chain reaction (PCR)-based test. Blood culture was performed on all neonates with suspected EOS. Among the subset fulfilling criteria for protocol-defined EOS, blood and nasopharyngeal (NP) respiratory swabs were tested by quantitative real-time reverse-transcriptase PCR using a Taqman Array Card (TAC) with 15 bacterial and 12 viral targets. Blood and NP samples from 312 healthy newborns were also tested by TAC to estimate background positivity rates. We used variant latent-class methods to attribute etiologies and calculate pathogen-specific proportions and incidence rates.

RESULTS

We enrolled 2,624 neonates with suspected EOS and from these 1,231 newborns met criteria for protocol-defined EOS (incidence- 39.3/1,000 live-births). Using the partially latent-class modelling, only 26.7% cases with protocol-defined EOS had attributable etiology, and the largest pathogen proportion were Ureaplasma spp. (5.4%; 95%CI: 3.6-8.0) and group B Streptococcus (GBS) (4.8%; 95%CI: 4.1-5.8), and no etiology was attributable for 73.3% of cases. Blood cultures were positive in 99/1,231 (8.0%) with protocol-defined EOS (incidence- 3.2/1,000 live-births). Leading pathogens on blood culture included GBS (35%) and viridans streptococci (24%). Ureaplasma spp. was the most common organism identified on TAC among cases with protocol-defined EOS.

CONCLUSION

Using a combination of blood culture and a PCR-based test the common pathogens isolated in neonates with sepsis were Ureaplasma spp. and GBS. Despite documenting higher rates of protocol-defined EOS and using a combination of tests, the etiology for EOS remains elusive.

Detection of Ureaplasma Species by a Semi-Quantitative PCR Test in Urine Samples: Can It Predict Clinical Significance?

BACKGROUND

Ureaplasma species (Usp) are the most prevalent genital Mycoplasma isolated from the urogenital tract of both men and women. Usp may be commensals in the genital tract but may also be contributors to a number of pathological conditions of the genital tract. Because they can also just colonize the genital tract of healthy people, their pathogenic role can be difficult to prove.

OBJECTIVES

The aim of the study was to evaluate the efficacy of a quantitative polymerase chain reaction (qPCR) method for the discrimination between infection and colonization by measuring prevalence of Usp in asymptomatic versus symptomatic patients.

METHODS

Urine samples were tested for U. parvum and U. urealyticum using a semi-quantitative multiplex PCR technique for sexually transmitted diseases (Anyplex™ STI-7 Detection Kit, Seegene, South Korea). A total of 250 symptomatic and 250 asymptomatic controls were included.

RESULTS

A strong positive result for U. parvum was significantly more prevalent in symptomatic compared to asymptomatic patients. This finding was observed especially in women and in the young group (15-35 years of age). No significant differences were observed between the prevalence in symptomatic and asymptomatic patients of U. parvum with low strength of positivity and for U. urealyticum in all groups by age, gender, and strength of positivity.

CONCLUSIONS

The significant difference between the symptomatic and asymptomatic group in the highest positivity group for U. parvum using the Anyplex™ STI-7 detection kit in urine may indicate a high probability of infection rather than colonization, especially in women and young patients.

The Human Ureaplasma Species as Causative Agents of Chorioamnionitis

The human Ureaplasma species are the most frequently isolated microorganisms from the amniotic fluid and placentae of women who deliver preterm and are also associated with spontaneous abortions or miscarriages, neonatal respiratory diseases, and chorioamnionitis. Despite the fact that these microorganisms have been habitually found within placentae of pregnancies with chorioamnionitis, the role of Ureaplasma species as a causative agent has not been satisfactorily explained. There is also controversy surrounding their role in disease, particularly as not all women infected with Ureaplasma spp. develop chorioamnionitis. In this review, we provide evidence that Ureaplasma spp. are associated with diseases of pregnancy and discuss recent findings which demonstrate that Ureaplasma spp. are associated with chorioamnionitis, regardless of gestational age at the time of delivery. Here, we also discuss the proposed major virulence factors of Ureaplasma spp., with a focus on the multiple-banded antigen (MBA), which may facilitate modulation/alteration of the host immune response and potentially explain why only subpopulations of infected women experience adverse pregnancy outcomes. The information presented within this review confirms that Ureaplasma spp. are not simply "innocent bystanders" in disease and highlights that these microorganisms are an often underestimated pathogen of pregnancy.

[The evaluation of detection rate of Mycoplasma hominis and Ureaplasma spp. using cultural technique and polymerase chain reaction]

In the clinical diagnostic laboratories of Chelyabinsk and St. Petersburg evaluation of detection rate of Mycoplasma hominis and Ureaplasma spp. was implemented using technique of polymerase chain reaction and cultural method. The reagents kits "Mycoplasma ACH-12" and "Ureaplasma ACH-12" were used to detect and determine antibiotics sensitivity of urogenital mycoplasma with determination of character of sensitivity of clinical isolates M.hominis and Ureaplasma spp. in sample of secretion of urethra and cervical channel. The results of study demonstrated that rate of detection of Ureaplasma spp. turned out significantly higher than M.hominis. The common coincidence of results in St. Petersburg between two techniques (polymerase chain reaction and cultural method) in case of detection of Ureaplasma spp. amounted to 97.5% and in case of detection of M.hominis - 93.5%.The common coincidence of the results in Chelyabinsk between two techniques (polymerase chain reaction and cultural method) in case of detection of Ureaplasma spp. amounted to 79.9% and in case of detection of M.hominis - 96.1%.

Correlation between Ureaplasma subgroup 2 and genitourinary tract disease outcomes revealed by an expanded multilocus sequence typing (eMLST) scheme

The multilocus sequence typing (MLST) scheme of Ureaplasma based on four housekeeping genes (ftsH, rpL22, valS, and thrS) was described in our previous study; here we introduced an expanded MLST (eMLST) scheme with improved discriminatory power, which was developed by adding two putative virulence genes (ureG and mba-np1) to the original MLST scheme. To evaluate the discriminatory power of eMLST, a total of 14 reference strains of Ureaplasma serovars and 269 clinical strains (134 isolated from symptomatic patients and 135 obtained from asymptomatic persons) were investigated. Our study confirmed that all 14 serotype strains could successfully be differentiated into 14 eMLST STs (eSTs), while some of them could not even be differentiated by the MLST, and a total of 136 eSTs were identified among the clinical isolates we investigated. In addition, phylogenetic analysis indicated that two genetically significantly distant clusters (cluster I and II) were revealed and most clinical isolates were located in cluster I. These findings were in accordance with and further support for the concept of two well-known genetic lineages (Ureaplasma parvum and Ureaplasma urealyticum) in our previous study. Interestingly, although both clusters were associated with clinical manifestation, the sub-group 2 of cluster II had pronounced and adverse effect on patients and might be a potential risk factor for clinical outcomes. In conclusion, the eMLST scheme offers investigators a highly discriminative typing tool that is capable for precise epidemiological investigations and clinical relevance of Ureaplasma.

[The comparison of tests for qualitative evaluation of Ureaplasma parvum, Mycoplasma hominis: "Mycoplasma duo", "Ureaplasma microtest", "Mycoplasma microtest" and "AmpliSens-Florocenosis-mycoplasma-FL"]

The genital mycoplasma is an opportunistic bacteria and its detection is to be implemented in qualitative format. The study was organized to compare reagents kits "Mycoplasma Duo", "Ureaplasma Microtest", "Mycoplasma microtest" and "AmpliSens-Florocenosis-Mycoplasma-FL". The study resulted in high indicators of diagnostic sensitivity and diagnostic specificity for all kits. At that, the lowest indicators were registered under application of "Mycoplasma Duo" kit. The study reveled correlation of qualitative values detected by using cultural analysis and polymerase chain reaction. The reproducibility of qualitative values of cultural method occurred significantly lower in comparison with "AmpliSens-Florocenosis-Mycoplasma-FL " kit.

The role of the multiple banded antigen of Ureaplasma parvum in intra-amniotic infection: major virulence factor or decoy?

The multiple banded antigen (MBA) is a predicted virulence factor of Ureaplasma species. Antigenic variation of the MBA is a potential mechanism by which ureaplasmas avoid immune recognition and cause chronic infections of the upper genital tract of pregnant women. We tested whether the MBA is involved in the pathogenesis of intra-amniotic infection and chorioamnionitis by injecting virulent or avirulent-derived ureaplasma clones (expressing single MBA variants) into the amniotic fluid of pregnant sheep. At 55 days of gestation pregnant ewes (n = 20) received intra-amniotic injections of virulent-derived or avirulent-derived U. parvum serovar 6 strains (2×10⁴ CFU), or 10B medium (n = 5). Amniotic fluid was collected every two weeks post-infection and fetal tissues were collected at the time of surgical delivery of the fetus (140 days of gestation). Whilst chronic colonisation was established in the amniotic fluid of animals infected with avirulent-derived and virulent-derived ureaplasmas, the severity of chorioamnionitis and fetal inflammation was not different between these groups (p>0.05). MBA size variants (32–170 kDa) were generated in vivo in amniotic fluid samples from both the avirulent and virulent groups, whereas in vitro antibody selection experiments led to the emergence of MBA-negative escape variants in both strains. Anti-ureaplasma IgG antibodies were detected in the maternal serum of animals from the avirulent (40%) and virulent (55%) groups, and these antibodies correlated with increased IL-1β, IL-6 and IL-8 expression in chorioamnion tissue (p<0.05). We demonstrate that ureaplasmas are capable of MBA phase variation in vitro; however, ureaplasmas undergo MBA size variation in vivo, to potentially prevent eradication by the immune response. Size variation of the MBA did not correlate with the severity of chorioamnionitis. Nonetheless, the correlation between a maternal humoral response and the expression of chorioamnion cytokines is a novel finding. This host response may be important in the pathogenesis of inflammation-mediated adverse pregnancy outcomes.

Necrotizing enterocolitis is associated with ureaplasma colonization in preterm infants

The study objective was to determine whether Ureaplasma respiratory tract colonization of preterm infants <33 wk gestation is associated with an increased risk for necrotizing enterocolitis (NEC). One or more tracheal or nasopharyngeal aspirates for Ureaplasma culture and PCR were obtained during the first week of life from 368 infants <33 wk gestation enrolled from 1999 to 2003 or from 2007 to 2009. NEC Bell stage ≥ 2 was confirmed by radiological criteria, and pathology, if available. Cord serum samples were analyzed for IL-6 and IL-1β concentrations, and placentas were reviewed for histological chorioamnionitis in the first cohort. NEC was confirmed in 29 of 368 (7.9%) of the combined cohorts. The incidence of NEC was 2.2-fold higher in Ureaplasma-positive (12.3%) than Ureaplasma-negative (5.5%) infants <33 wk (OR, 2.43; 95% CI, 1.13-5.2; p = 0.023) and 3.3-fold higher in Ureaplasma-positive (14.6%) than Ureaplasma-negative (4.4%) infants ≤ 28 wk (OR, 3.67; 95% CI, 1.36-9.93; p = 0.01). Age of onset, hematologic parameters at onset, and NEC severity were similar between Ureaplasma-positive and negative infants. Cord serum IL-6 and IL-1β concentrations were significantly higher in Ureaplasma-positive than in Ureaplasma-negative NEC-affected infants. Ureaplasma may be a factor in NEC pathogenesis in preterm infants by contributing to intestinal mucosal injury and/or altering systemic or local immune responses.

Ureaplasma infection and neonatal lung disease

Infection with the ureaplasmas may occur in utero or perinatally in prematurely born infants. For some infants, infection with these organisms triggers a vigorous pro-inflammatory response in the lungs and increases the risk of developing bronchopulmonary dysplasia (BPD). At present, there is insufficient evidence from clinical trials to determine whether antibiotic treatment of Ureaplasma has any influence on the development of BPD and its comorbidities. Future investigation in the context of well-designed, adequately powered controlled clinical trials should focus on determining whether treatment of ureaplasmal infection lessens lung inflammation, decreases rates of BPD, and improves long-term, neurodevelopmental outcome.

Comparative genome analysis of Ureaplasma parvum clinical isolates

Ureaplasma parvum colonizes human mucosal surfaces, primarily in the respiratory and urogenital tracts, causing a wide spectrum of diseases, from non-gonococcal urethritis to pneumonitis in immunocompromised hosts. Although the basis for these diverse clinical outcomes is not yet understood, more severe disease may be associated with strains harboring a certain set of strain-specific genes. To investigate this, whole genome DNA macroarrays were constructed and used to assess genomic diversity in 10 U. parvum clinical strains. We found that 7.6% of U. parvum genes were dispersed into one or more strains, thus defining a minimal functional core of 538 U. parvum genes. Most of the strain-specific genes (79%) were of unknown function and were unique to U. parvum. Four hypervariable plasticity regions were identified in the genome containing 93% of the variability in the gene pool (UU32-UU33, UU145-UU170, UU440-UU447 and UU527-UU529). We hypothesized that one of them (UU145-UU170) was a pathogenicity island in U. parvum and we characterized it. Thus, we propose that the clinical outcome of U. parvum infection is probably associated with this newly identified pathogenicity island.

Mycoplasmal antibodies as determined with an enzyme-linked immunosorbent assay, in tubal factor infertility

A total of 81 infertile women, who had been referred for diagnostic loparoscopy, were tested for the presence of antibodies to Mycoplasma hominis and T-mycoplasma. Out of 81, 30 had tubal adhesions and 51 had unilateral/bilateral tubal blockage. Antibodies to M. hominis were found in 21/30 (70%) and 14/51 (27.45%) women, antibodies to T-mycoplasma in 12/20 (40% and 39/51 (76.47%) women with tubal disorder. In a control group of 40 pregnant women, antibodies to the same two organisms occurred in 10% and 32.5%. Antibodies to M. hominis and T-mycoplasma were significantly (P < 0.001) more common in women with tubal disorder. Our results confirm the important role of M. hominis and T-mycoplasma in the aetiology of tubal infertility.

[Risk factors for Ureaplasma diversum infections in cattle of a tropical environment]

A case-control study, determined the influence of breed, age and number of deliveries as risk factors for Ureaplasma genital infections in Costa Rica dairy cattle. The animals with none or one delivery had a risk of infection 2.99 times higher than those with several parturition, regardless of breed. The risk was 1.95 times higher in Jersey than in Holstein, and decreased progressively until three deliveries. In cows with four deliveries there was a significant increase in the amount of animals infected and also a significant difference in the rate of infection between Holstein (27%) and Jersey (64%). Ureaplasma isolation was rare in cows with more than six deliveries.

Ureaplasma diversum infection in vitro alters prostaglandin E2 and prostaglandin F2a production by bovine endometrial cells without affecting cell viability

Bovine epithelial and stromal cells of the endometrium were inoculated with Ureaplasma diversum, pathogenic strain 2312, at 10(6) or 10(3) color-changing units (ccu)/ml in the presence of 1% fetal bovine serum (depleted of steroids by dextran-charcoal treatment) to assess the effect of infection on prostaglandin biosynthesis. When the inoculum of U. diversum was 10(6) ccu/ml, the concentration of U. diversum in the culture medium decreased with time. U. diversum was found on the epithelial and stromal cell monolayers, increasing in titer 100-fold, indicating that attachment and eventually growth occurred. When the inoculum was 10(3) ccu/ml, the titer of U. diversum remained the same or increased in the supernatant and increased on epithelial and stromal cells. The effect of infection was evaluated by measurement of the primary prostaglandin produced by each cell type, prostaglandin F2a for epithelial cells and prostaglandin E2 for stromal cells. Infection with U. diversum significantly decreased prostaglandin F2a accumulation, by 44.7% +/- 6.0% at 10(6) ccu/ml (P < or = 0.005) and 15.8% +/- 5.3% at 10(3) ccu/ml (P < or = 0.05) in epithelial cells. Prostaglandin E2 accumulation by stromal cells was decreased by 34.0% +/- 4.0% at 10(6) ccu/ml (P < or = 0.001) and by 13.5% +/- 2.7% at 10(3) ccu/ml (P < or = 0.005). Infection with 10(6) ccu/ml did not alter endometrial cell viability, as shown by protein measurement, trypan blue dye exclusion, and cell plating efficiency tests. Thus, alterations in prostaglandin production were not due to cell deterioration. These observations suggest that U. diversum can alter prostaglandin E2 and prostaglandin F2a patterns in primary cultures of bovine endometrial cells without affecting cell viability.

[Mycoplasmas and mycoplasmosis: the etiopathogenetic problems and nosological, clinical and diagnostic advances]

Authors point out, on the basis of literature and of their own experience, the following aspects of Mycoplasma infections: 1) Genetical and biological progresses, especially related to pathogenetic aspects and diagnostic procedures. 2) Recent clinical and diagnostic findings of M. pneumoniae infections: "bacteria-like" pulmonary presentations by mycoplasmas (and, on the contrary, "virus-like" pulmonary presentations by bacteria); atypical kinds of pulmonary presentations by mycoplasmas; role of autoimmunity in extrapulmonary involvement. 3) Relationship among mycoplasmas, immune system and autoimmune diseases, with particular regard to animal models and to the Mycoplasma "superantigen". 4) Appearance of new pathogens and of a new spectrum of Mycoplasma infections: genito-urinary involvement by Ureaplasma urealyticum and by M. Hominis; relationship between Mycoplasma spp. and HIV infection.

Comparison of pathological signs of disease in specific-pathogen-free calves after inoculation of the respiratory tract with Ureaplasma diversum or Mycoplasma canis

To confirm the pathogenic role of Ureaplasma diversum in respiratory disease of calves, we inoculated caesarean-delivered, colostrum-deprived calves intranasally with a dose of 10(7) colour-changing units (CCU) or endobronchially with a dose of 10(10) CCU. Clinical signs of respiratory disease were not observed, but in the endobronchially inoculated calves, thick cuffs of round cells surrounded the bronchi, bronchioli and blood vessels, and a lobular catarrhal pneumonia developed. It was concluded that the pathogenicity of U. diversum can be demonstrated after endobronchial but not after intranasal inoculation. Similar calves were inoculated endobronchially with a dose of 2 x 10(10) colony-forming units of Mycoplasma canis. Clinical signs of respiratory disease were not observed. At day 2 after inoculation, only slight pathological signs of respiratory disease were detected, and these disappeared at day 9. M. canis was not recovered from the lungs. Hence, M. canis could not be clearly identified as a pathogen in respiratory disease of calves. By comparing the results of the various experiments, we concluded that thin cuffs of round cells in the lungs can indicate mycoplasma infections, but that these are not necessarily pathognomonic.

Localization of endogenous activity of phospholipases A and C in Ureaplasma urealyticum

Endogenous activities of phospholipases A and C in Ureaplasma urealyticum were assayed in cellular fractions of exponential-phase cells. Enzymatic studies indicated that ATPase activity was localized in the plasma membrane fraction and NADH and NADPH dehydrogenase activities were localized in the cytosol fraction. Studies with purified ureaplasma membranes demonstrated that, of three serovars tested, endogenous phospholipase A1, A2, and C activities were localized in the plasma membrane. Very low levels of activity were observed in the cytosol fractions. Phospholipase A2 activity in the plasma membrane was 3- to 5-fold higher than the activity in the lysates and 60- to 300-fold higher than the activity of phospholipase A1. Phospholipase C was localized mainly in the plasma membrane, with 20% found in the cytosol fraction. The levels of activity were comparable among the three serovars. There was a significantly lower level of activity in cells from the stationary growth phase than in the exponential phase. Significant differences were observed in the phospholipase A activities among the U. urealyticum serovars 3, 4, and 8. Phospholipase A2 activity was twofold higher in serovar 8 membranes, and phospholipase A1 activity was twofold higher in serovar 3 membranes. These results demonstrate that endogenous activities of phospholipase A and C are localized primarily in the plasma membrane fraction of U. urealyticum. The specific activities in the membranes of the phospholipases varied among the three serovars. Phospholipase enzymes may function as virulence factors in U. urealyticum and may vary among the serovars.

[Ureaplasma urealyticum--a new problem pathogen in neonatology]

Some previous studies showed that Ureaplasma urealyticum is the most common germ that appears in the birthway of pregnant women and which is also frequently found in skin swabs and secretions of newborn and premature babies. The colonization of pregnant women by Ureaplasma urealyticum makes a premature birth more likely. Another factor of risk for a premature infant is a premature rupture of membranes for more than 24 hours which also makes an infection possible. There exists an association between pulmonary infection by Ureaplasma urealyticum and the development of a bronchopulmonary dysplasia especially for premature babies. According to our observations acute exacerbations of severe pneumonia can appear even after month. An attempt of therapy of pulmonary infection should be undertaken with erythromycin, if sensitive serotypes are present. In the case of erythromycin resistance chloramphenicol can be used but only under frequent controls of blood levels. We were able to observe rapid improvements with this effective therapy.

Perinatal mycoplasmal infections

Maternal infections are known to play a major role in perinatal morbidity and mortality. Ureaplasma urealyticum and Mycoplasma hominis are sexually transmissible microorganisms associated with a number of pathologic conditions in the pregnant woman including chorioamnionitis and postpartum fever. They are rapidly gaining recognition as significant causes of perinatal infection, especially in infants born prematurely. This review summarizes current knowledge regarding the epidemiology, pathology, disease spectrum, and clinical manifestations of mycoplasmal and ureaplasmal perinatal infections and presents guidelines for proper diagnosis and treatment.

Survival of feline mycoplasmas in urine

The effects of length of incubation and urine osmolality on the survival of feline mycoplasmas and ureaplasmas and representative gram-positive and gram-negative bacteria in synthetic urine which approximated the osmolality of normal cat urine were investigated. Both Escherichia coli and Staphylococcus aureus withstood the effects of increasing osmotic pressure. In the most concentrated urine, significant decreases (P less than 0.001) in CFU were observed for E. coli at exposure times of 30 min and longer. S. aureus was not affected by longer exposure or increased osmotic strength. Both Mycoplasma felis and Mycoplasma gateae were affected adversely by longer exposure times and high osmotic strength (P less than 0.001). A Ureaplasma sp. was not adversely affected except at very high (greater than or equal to 2,980 mosM) osmotic strengths or after prolonged incubation (120 min) at relatively high (1,976 mosM) osmotic strengths (P less than 0.001). The failure of both M. felis and M. gateae to survive under osmotic conditions present in normal feline urine suggests that it is unlikely that these mycoplasmas are involved in urinary disorders in cats.

[Value and limitations of the research of Mycoplasma hominis and Ureaplasma urealyticum in gastric fluid in newborn infants]

Mycoplasma hominis and Ureaplasma urealyticum were cultured and counted in the gastric fluid of 153 neonates divided into three groups: 28 preterm neonates managed in an intensive care unit (Group I); 83 full term neonates with suspected infection (Group II); and 42 full term neonates with not evidence of infection (Group III). The colonization rate (17.85%) in the intensive care unit group was not significantly different from the rates seem in the two other groups. These results do not militate against the pathogenic role of the two organisms studied but rather suggest a contributory role of other factors.

Biochemical and histologic findings in experimental pyelonephritis due to Ureaplasma urealyticum

Ureaplasma urealyticum has previously been shown to be capable of persisting in the rat kidney for up to 6 months following a single reflux challenge. We examined kidney tissue from infected animals for evidence of renal damage by using standard cytochemical and immunoenzyme methods. We also monitored changes in renal function during a 6-month study period with standard biochemical assays of plasma and urine. Histologic examination showed tubular atrophy, interstitial fibrosis, and a mononuclear infiltrate in proportion to ureaplasma counts from renal tissue. The most severe damage was accompanied by hyaline cast formation within tubules which gave rise to the typical thyroidlike appearance of chronic pyelonephritis involving conventional urinary pathogens. Macroscopic renal scarring occurred in some animals. Although damage to the renal medulla was moderate to severe, only minor changes were seen in the cortex, and glomeruli were invariably spared. Biochemical tests of renal function showed similar changes in infected and uninfected animals during the study period. Interstitial inflammation was characterized by a mononuclear cell infiltrate in which polymorphonuclear leukocytes were not conspicuous. It is evident that U. urealyticum is capable of producing chronic pyelonephritis in the rat after a single reflux challenge. The results of this study have obvious implications for the pathogenicity of these bacteria in human pyelonephritis.

[The infection of monkeys with Ureaplasma urealyticum serovar VIII]

The possibility of modeling chronic infection on monkeys by the injection of the culture of U. urealyticum, serotype VIII, was shown. The infection of monkeys with these microorganisms introduced in a single intraperitoneal injection resulted in the generalization of the process, which was manifested by the persistence and reproduction of the infective agent in the organs and blood of the animals for as long as 6 months (the term of observation). Lymphoid hyperplasia in the organs of immunogenesis and transitory immunomorphological reaction in the tissues of some organs of the urogenital system were noted. The localization of infective agents in some endocrine glands was not accompanied by disturbances in their function.

Ureaplasma urealyticum upper urinary tract infection: persistence and pathogenicity in a canine model

Ureaplasma urealyticum is an opportunistic pathogen, commonly isolated from the lower urogenital tract. Although U. urealyticum has been cultured from the upper urinary tracts of patients with interstitial renal diseases and struvite renal calculi, the precise role of ureaplasmas in upper tract diseases is unknown. To evaluate their potential significance in the etiology of renal diseases, we studied survival, multiplication, and pathogenicity of U. urealyticum in canine kidneys with experimentally induced hydronephrosis. After inoculation of the prototypic serovar (Type 8, strain 960) of U. urealyticum, seral urine specimens were obtained using a subcutaneously positioned nephrostomy catheter. Although U. urealyticum survived for less than 48 hours in canine urine in vitro, organisms persisted in the obstructed upper urinary tract for at least 21 days. Urinary pH of infected renal units increased to 7.5 to 8.5, a most unfavorable range for U. urealyticum in culture. Renal parenchyma had higher concentrations of ureaplasmas (8.7 X 10(3) to 9.5 X 10(4) CFU/gm.) than either renal pelvis tissue (1.0 X 10(3) CFU/gm.) or urine (6.5 X 10(3) CFU/ml.). Histologic studies demonstrated progressive interstitial inflammation in infected kidneys but similar changes were not apparent in obstructed, uninfected kidneys. The obstructed upper urinary tract appears to provide favorable conditions for ureaplasmas which may cause progressive interstitial inflammation in the absence of other pathogens.

Ureaplasma urealyticum pneumonia: experimental production and demonstration of age-related susceptibility

Two different strains of Ureaplasma urealyticum isolated in pure culture from the lungs of newborn human infants were shown to produce an acute, self-limiting, interstitial pneumonia in newborn C3H/HeN and C57BL/6 mice that were free of other respiratory pathogens. Lesion severity peaked 3 to 6 days following intranasal inoculation of ureaplasmas and was resolved by 12 days. Rhinitis and otitis also occurred but did so less frequently than pneumonia. Organisms were localized within the alveoli in areas of inflammation. In comparison with newborn mice, 14-day-old mice were less susceptible to either colonization or disease.

Serotypes of Ureaplasma urealyticum isolated from normal pregnant women and patients with pregnancy complications

To compare the distribution of Ureaplasma urealyticum serotypes 1 to 10 in different patient populations, the serotypes of 240 U. urealyticum strains from 207 patients were determined by the indirect immunofluorescence test by using U. urealyticum antisera 1 to 10. Strains were obtained from the following four patient groups: group 1, 24 couples in which the women had a history of recurrent spontaneous abortion; group 2, 25 patients who had their first spontaneous abortion; group 3, 14 pregnant patients with pregnancy complications (premature delivery, intrauterine death); and group 4, 138 patients with uneventful pregnancies. The serotypes most often found in these 207 patients were as follows: serotype 3, 52.2%; serotype 6, 30.3%; serotype 10, 11.4%; serotype 1, 9.5%; serotype 4, 6.5%; serotype 8, 6.5%. Serotypes 2, 5, 7, and 9 were found in less than 1% of the patients. More than one serotype was found in 16.9% of the patients. The overall distribution of the 10 serotypes in the different groups was similar, except for that of serotype 4. Serotype 4 was isolated from 20.8% of the patients in group 1 and from 5.1% of the patients in group 4 (P less than 0.01). Results of this study indicate that U. urealyticum serotype 4 can be isolated more frequently from patients with a history of recurrent miscarriages than from normal pregnant women.

Ureaplasma-urealyticum-induced bladder stones in rats and their prevention by flurofamide and doxycycline

Struvite calculi can be produced in the bladder of Sprague-Dawley male rats after injection of ureaplasmas into the renal medulla. Calculi appear 3 to 6 days after ureaplasma injection. We have studied the inhibitory effect of flurofamide, a potent inhibitor of Ureaplasma urealyticum urease, and doxycycline, on the formation of bladder stones. Flurofamide given orally in five doses (total 125 mg) over 3 days and doxycycline in seven doses (total 20 mg) over 4 days partially prevented stone formation only when given at the time of inoculation. Ureaplasmas disappeared rapidly from the urine. The inhibitory effect of flurofamide was higher than that of doxycycline. However, doxycycline seemed to be efficient when given for a long period (5 weeks).

The potential of the ovine udder as a model to determine the pathogenicity of bovine ureaplasmas

Various methods of inducing mastitis in the ovine mammary gland with two bovine ureaplasma strains were investigated. The most successful method was by inoculation of fresh broth cultures on two successive days, 24 h apart. Eight more bovine strains were inoculated by this means and three successfully infected the glands.

In vitro exposure of bovine morulae to Ureaplasma diversum

Ureaplasma diversum has been associated with infertility in the cow experimentally and in naturally occurring cases. However, the pathogenic mechanism is undetermined. The purpose of this study was to determine whether ureaplasmas are pathogenic for bovine morulae in vitro. Twenty-one morulae were recovered from three superovulated, mature, Holstein cows six or seven days postestrus. The embryos were divided into three groups (A,B,C) and incubated for 16 hours at 37 degrees C in humidified air with 10% CO2. Group A was incubated in embryo culture medium alone, Group B was incubated in culture medium with sterile ureaplasma broth added and Group C was incubated in culture medium containing 1.7 X 10(6) colony forming units Ureaplasma diversum strain 2312. After incubation, the morulae were examined using an electron microscope. Structures morphologically identical to U. diversum were present on the outer surface of the zonae pellucidae of all the morulae exposed to the organism and none were present on the unexposed control embryos. No other morphological differences were observed in either the ureaplasma-exposed embryos or the two groups of control embryos. Ureaplasma diversum was isolated from three of the five embryos incubated in culture medium with sterile ureaplasma broth added. These three embryos were recovered from one donor cow which cultured positive for U. diversum from the vulva and flush fluid. This finding suggests that the contaminating organisms entered the embryo culture wells either in the embryo collection medium or attached to the embryos.(ABSTRACT TRUNCATED AT 250 WORDS)

[Experimental Mycoplasma infection of the urogenital tract in monkeys]

The possibility of the experimental reproduction of infectious urethritis in monkeys by infecting them with mycoplasma and ureaplasma cultures, newly isolated from human patients, has been shown. In monkeys inoculated with the mixture of mycoplasmas and ureaplasmas, more pronounced infectious urethritis with the symptoms of ascending infection develops. The animals who have had the disease do not develop resistance to repeated infection.

Pathogenesis and significance of urogenital mycoplasmal infections

U. urealyticum and M. hominis can no longer be considered as harmless commensals of the lower genitourinary tract. Both can produce disease in humans. Diagnosis and management of infections due to these organisms must be based upon isolation of the organisms from the affected site and preferably the number of organisms present. Due to the frequent resistance of both organisms to tetracycline, treatment must be based upon appropriate antibiotic sensitivities. For a more detailed description of the basic biology of these organisms and isolation and identification and treatment, the reader is referred to several recent reviews.

Evidence for pathogenicity of Ureaplasma urealyticum for the upper urinary tract derived from animal models

In limited clinical studies ureaplasmas have been cultured from the upper urinary tracts of some patients with struvite renal calculi and interstitial renal diseases. Struvite calculi were also produced in rats by inoculation of human ureaplasmas. We found that a type 8 strain of Ureaplasma urealyticum survived for at least 21 days and replicated following inoculation into the experimentally obstructed canine upper urinary tract. Development of severe chronic interstitial renal inflammation was accompanied by 10-fold rises in systemic anti-urea-plasmal antibody titers. This animal model should prove to be useful for investigating the potential role of ureaplasmas as opportunistic pathogens of the upper urinary tract.

Ureaplasma urealyticum in the immunocompromised host

The lack of antibody in hypogammaglobulinemic patients probably results in failure of mycoplasmas to be "neutralized" and accounts for the diminished ability of the patients to cope with these organisms escaping hematogenously from the respiratory and urogenital tracts. Furthermore Ureaplasma urealyticum and other mycoplasmas are ingested by neutrophils in the absence of opsonins, indicated by the fact that they are able to trigger the release of chemiluminescence from these cells; ureaplasmas are not killed during this process and it is possible that carriage occurs within phagocytes to various sites. Several mycoplasmal species have localized in joints and U. urealyticum organisms are no exception. They have been isolated from the purulent synovial fluids of at least three hypogammaglobulinemic patients in Canada, England and the United States, respectively, the arthritides responding to appropriate antibiotic therapy. In one male patient, however, repeated and prolonged episodes of arthritis over several years, associated with antibiotic-resistant ureaplasmas, responded only to the administration of specific hyperimmune serum. Apart from joint involvement subcutaneous abscesses have been seen, and in the latter patient persistent urethritis was caused by ureaplasmas, these being the only organisms recovered from the urethra. Chronic urethrocystitis/cystitis in hypogammaglobulinemic patients has been associated also with ureaplasmal infection. In addition polyarthritis with recovery of both ureaplasmas and Mycoplasma hominis from the joints has been seen in a kidney allograft patient on an immunosuppressive regimen. However, further evidence that ureaplasmas cause a problem in immunosuppressed patients or in those with the acquired immunodeficiency syndrome is lacking.

Potential virulence factors of Ureaplasma urealyticum

Our understanding of the pathogenic potential of Ureaplasma urealyticum awaits further characterization of the species. This review adds recently published findings to the previously established properties of this myocoplasma.

Ureaplasma colonization: definitions and epidemiologic implications

Genital mucosal colonization with Ureaplasma species complicates interpretation of their role as pathogens. From an epidemiologic point of view, colonization should be considered a dynamic process in which knowledge about the habitat colonized is an integral part. The classical criteria of pathogenicity need to be broadened to include qualitative, quantitative, and temporal aspects as disease associations of ureaplasmas are explored.

Persistent urethritis due to Ureaplasma urealyticum in conjugal or stable partnerships

A study of four conjugal partnerships is described in which the male partners presented with persistent or recurrent non-gonococcal, non-chlamydial, but ureaplasma positive urethritis. Resolution of symptoms and signs in the male partners was achieved only after treatment to eliminate Ureaplasma urealyticum from both partners.

The ovine mammary gland as an experimental model to determine the virulence of animal ureaplasmas

As an estimate of their virulence, the ability of ovine, bovine, canine, feline and simian ureaplasma strains to cause mastitis in the ovine mammary gland was investigated. Five ovine ureaplasmas produced a clinical mastitis. Broth cultures of seven bovine ureaplasmas were unable to infect the ovine gland, but two of these strains plus one other were able to do so following passage through the bovine udder. One of two canine strains and a feline strain both caused mastitis, but the simian strain persisted at low titre for only 5 days post-inoculation in one of the two ewes tested.

Experimental intrauterine inoculation of pregnant ewes with ureaplasmas

The pregnancies of 13 ewes which were inoculated intrauterine with one of two strains of ovine ureaplasmas resulted in 9 normal and 3 abnormal births, and one ewe was found to be no longer pregnant on postmortem examination. Vaginal ureaplasma infection was detected in the majority of ewes only after lambing. Of the 12 ewes examined at postmortem, ureaplasmas were isolated from the uterus of 5 out of the 6 necropsied up to 21 days post-partum. The vulvar/preputial areas of the majority of lambs that survived were infected with ureaplasmas for the duration of the experiment, but infections of the nasal cavity and eye areas, detected at birth in 4 lambs, were resolved within 8 days post-partum. The only pathological effects detected that could possibly be attributed to ureaplasma infection were a placentitis in an ewe that aborted, and the resorption of the foetus in another.

Stone formation by Ureaplasma urealyticum in human urine and its prevention by urease inhibitors

When Ureaplasma urealyticum T-960 was inoculated into normal human urine (10(8) viable cells per ml of urine), a white precipitate formed, with an increase in pH of the infected urine. This precipitate was identified as a mixture of struvite and whitelockite by analysis of the infrared spectrum. Its formation was completely prevented by the addition of 10 microM N-benzoylphosphotriamide, 20 microM N-isopentenoylphosphotriamide, or 0.5 mM caprylohydroxamic acid without the alkalinization of the urine, and the Ureaplasma color change units were also decreased markedly by these compounds. The apparent concentrations for 50% inhibition by N-benzoylphosphotriamide,N-isopentenolyphosphotriamide, and caprylohydroxamic acid against Ureaplasma urease were 7 nM, 2 nM, and 2.2 microM, respectively. From these results, it seems that stone formation by U. urealyticum is prevented with these compounds, that prevention being directly attributable to the inhibition of urease activity, which causes the death of the cells.

The experimental production of mastitis in ewes as a determinant of the virulence of ovine ureaplasma strains

Seven out of eight ovine ureaplasma strains inoculated into the mammary gland of suckling ewes produced a mastitis. The pattern of infection was single phase in 5 ewes, persisting for 12-41 days, and biphasic in 3 ewes, persisting in 2 of them until weaning at 60 days and 3 months post-infection. Sucking lambs did not become infected in the eye or nasal areas, and did not transfer infection to the control contralateral glands.