Isolation of Mycoplasma hominis from cerebrospinal fluid

Mycoplasmas and ureaplasmas as neonatal pathogens

The genital mycoplasmas represent a complex and unique group of microorganisms that have been associated with a wide array of infectious diseases in adults and infants. The lack of conclusive knowledge regarding the pathogenic potential of Mycoplasma and Ureaplasma spp. in many conditions is due to a general unfamiliarity of physicians and microbiology laboratories with their fastidious growth requirements, leading to difficulty in their detection; their high prevalence in healthy persons; the poor design of research studies attempting to base association with disease on the mere presence of the organisms in the lower urogenital tract; the failure to consider multifactorial aspects of diseases; and considering these genital mycoplasmas only as a last resort. The situation is now changing because of a greater appreciation of the genital mycoplasmas as perinatal pathogens and improvements in laboratory detection, particularly with regard to the development of powerful molecular nucleic acid amplification tests. This review summarizes the epidemiology of genital mycoplasmas as causes of neonatal infections and premature birth; evidence linking ureaplasmas with bronchopulmonary dysplasia; recent changes in the taxonomy of the genus Ureaplasma; the neonatal host response to mycoplasma and ureaplasma infections; advances in laboratory detection, including molecular methods; and therapeutic considerations for treatment of systemic diseases.

A fatal case of Mycoplasma hominis meningoencephalitis in a full-term newborn

We report the case of a 20-day-old full-term baby, born to a mother who had had an uncomplicated pregnancy and delivery, who died 13 days after the onset of meningitis. Mycoplasma hominis was the sole agent repeatedly recovered from cerebrospinal fluid and from postmortem brain tissue.

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.

Mycoplasma hominis in maternal and fetal infections

Although prevalence of M. hominis colonization during pregnancy varies from 12-50%, its role in infections of the mother and newborn infants is unclear. Definite correlations exist with chorioamnionitis and amniotic fluid infections, but as it is rarely isolated alone during these infections, its pathogenic role is uncertain. Its association with septic abortion is similarly questioned. Prevalence and antibody titers to M. hominis increase with increasing parity. Transient bacteremia occurs in approximately 2.5% of normal deliveries. M. hominis does have a significant role in postpartum fever. Women harboring the organism during labor with low predelivery antibody titers are at risk. Approximately 30% of exposed infants are colonized (4% of all infants) but there are only a few reports of neonatal meningitis, pneumonia, or skin abscesses due to M. hominis. Most recover without specific therapy. The role of antimicrobial therapy of M. hominis in pregnancy and the neonatal period is unclear. Further studies of these issues should simultaneously consider all potential genital tract pathogens.

Chronic Ureaplasma urealyticum and Mycoplasma hominis infections of central nervous system in preterm infants

In a prospective study of meningitis in 100 predominantly preterm infants, Ureaplasma urealyticum was isolated from the cerebrospinal fluid (CSF) of 8 and Mycoplasma hominis from the CSF of 5 babies undergoing investigation of suspected sepsis or treatment of hydrocephalus. U urealyticum was isolated from 6 infants with severe intraventricular haemorrhage and from 3 with hydrocephalus. In 4 babies multiple isolations were made over several weeks. There were clinical features of congenital infection with major neurological impairment in 1 infant infected with M hominis. Diagnosis is difficult because these organisms cannot be seen on gram stain and cannot readily be cultivated on routine bacteriological media, and CSF pleocytosis may be absent. This study, which used appropriate mycoplasmal media, shows that U urealyticum and M hominis are the most common microorganisms isolated from the CSF of newborn infants in a high-risk population.

Role of genital mycoplasmas in young infants with suspected sepsis

To establish the prevalence of Mycoplasma hominis and Ureaplasma urealyticum in infants up to 3 months of age with suspected sepsis, blood, cerebrospinal fluid, and urine specimens from 203 patients with clinical signs and symptoms of sepsis were cultured for Mycoplasma in addition to routine bacterial cultures. Proved bacterial infections were identified in 24 patients, four of whom had bacteremia. M. hominis and U. urealyticum were not isolated from any of the 191 blood and 199 CSF specimens tested. Of 170 specimens of urine cultured for Mycoplasma, M. hominis was isolated in six patients, U. urealyticum in nine patients, and both organisms in one patient. Twelve of the positive cultures were voided urine specimens, and four were suprapubic bladder aspiration specimens. Genital mycoplasmas appear to be uncommon causes of sepsis or meningitis in young infants. Further studies are required to assess their role in abnormal conditions of the urinary tract in childhood.

Septicemia due to Mycoplasma hominis

Mycoplasma hominis was recovered from the blood of 7 patients with various underlying disorders. One patient had a legal abortion, another a Caesarian section, both followed by septicemia. Three patients had genital infections in pregnancy, followed by septicemia and spontaneous abortion. M. hominis was also recovered from cervix and urethra in 2 of these women. High serum antibody levels against M. hominis were demonstrated in 3 women. One female developed septicemia after cancer surgery, one male after heart surgery. In the first 6 patients described the septicemia was of short duration and self-limiting, in the 7th patient it was of long duration and appropriate antimicrobial treatment was required. From this patient M. hominis was also isolated from infected operation wounds.

Infection of a brain abscess of Mycoplasma hominis

Persistent fever in a young man after evacuation of a subdural hematoma caused by a depressed skull fracture made it necessary to carry out a computerized tomographic exam of the head that demonstrated a left frontal lobe brain abscess. Mycoplasma hominis was recovered from this abscess as the sole infecting organism. Serial computerized tomographic scans showed resolution after aspiration and antibiotic therapy.

Meningitis in a newborn infant caused by Mycoplasma hominis

When 10 days old an infant born after 34-35 weeks of gestation developed meningitis with pleocytosis and a low glucose concentration in the cerebrospinal fluid. Mycoplasma hominis was recovered from the cerebrospinal fluid and treatment with doxycycline was given. The strain was later found to be resistant to tetracycline. After institution of lincomycin, cultures for mycoplasmas were negative. The infant, who during the course of the meningitis had developed a transient increase in intracranial pressure, was healthy and normally developed at the age of one year.--This is the first report on an infection caused by a tetracycline-resistant strain of Mycoplasma hominis.

Mycoplasma-induced hydrocephalus in rats and hamsters

Mycoplasma pulmonis, a pathogen of the respiratory tract in rats, was inoculated intracerebrally into neonate rats and hamsters to determine if it would induce lesions in the ependyma. Hydrocephalus was induced in 116 of 120 rats and in 23 of 28 hamsters. The severity of hydrocephalus was greater in the rats than in the hamsters. Hydrocephalus induction occurred only subsequent to inoculation of viable M. pulmonis. At 2 weeks of age, rats became refractory to induction of hydrocephalus. Light microscopy indicated that the hydrocephalus was communicating without an inflammatory response in the ventricles and meninges. Preliminary electron microscopy revealed that amorphous material covered portions of the ependymal surface and that cilia were sometimes matted together. It was suggested that the hydrocephalus was due to ciliary dysfunction or to an imbalance of cerebrospinal fluid secretion and absorption. This M. pulmonis-induced hydrocephalus may be a useful model for elucidating the pathogenesis of certain types of congenital hydrocephalus in humans.

Non-specific urethritis and the tetracyclines

The possible aetiological factors in non-gonococcal and non-specific urethritis are reviewed. The response of NSU to various courses of different tetracycline drugs is assessed. Prolonged courses of treatment did not give better results than shorter courses. When reviewing the infective aetiology of non-gonococcal urethritis, it was noted that more than one organism (or potential pathogen) would be present in many cases. It is therefore surmised that there may be at times a mixed aetiology and at other times a truly non-specific aetiology. Isolations by different workers have indicated that the following organisms might be expected: Chlamydia 40 per cent.; Mycoplasma-M. hominis 20 per cent., T-strain over 60 per cent.; Trichomonas 15 per cent.; Candida possibly over 5 per cent. Truly non-specific urethritis may account for 25 to 30 per cent. of cases.