Diagnosis of some genital-tract infections: part 1. An historical perspective

Making a prompt and accurate diagnosis of genital tract infections is the key to instituting appropriate treatment and the linchpin of sexually transmitted infection control. We present a brief history, not covering syphilis, of diagnostic events for each of six bacteria and one protozoan from the time of discovery up to the molecular revolution. The latter is touched upon but its impact will form the substance of a further presentation. Here, hindsight is helpful in understanding the way in which progress was made over 135 years, often when microbiology, not even seen as a distinct discipline, had a difficult time in providing what was required in terms of dependable diagnostic techniques. Gram-staining, growth on artificial media, growth in cultured cells, enzyme immunoassays, metabolic and immunofluorescence tests have all had their place and some still do despite the avalanche of the molecular era. Serology to determine the existence of organism-specific antibodies has been important in managing syphilis, but has only sometimes been helpful in supporting a diagnosis for other infections and has rarely been the primary deciding factor.

Spontaneous abortion--an infectious aetiology?

The role of Chlamydia trachomatis, genital mycoplasmas, Campylobacter spp. and other aerobic and anaerobic bacteria in the aetiology of spontaneous abortion was investigated prospectively in 241 pregnant women at a community hospital. Sixteen women who had threatened abortions were a little younger, of lower social class and had had more previous spontaneous abortions than the 76 women who aborted or the 149 women whose pregnancies were not complicated in the early stages by haemorrhage. The demographic characteristics of the latter two groups of women were similar. C. trachomatis was isolated from the cervix of only one woman and she had no genital-tract bleeding at any stage in her pregnancy. Mycoplasma hominis was isolated most often from the women who had threatened abortions but otherwise the prevalence of the other various micro-organisms was similar in women who had spontaneous abortions, threatened abortions, and in those who had pregnancies uncomplicated by vaginal bleeding. It was clear, therefore, that C. trachomatis played no role in the aetiology of spontaneous abortion in the population studied and there was no suggestion that any of the other micro-organisms were involved either.

Chronic cystitis and urethritis associated with ureaplasmal and mycoplasmal infection in primary hypogammaglobulinaemia

Six of 58 patients with primary hypogammaglobulinaemia developed chronic urethritis and/or cystitis. We have some evidence that this complication may be caused by infection with strains Rof Ureaplasma urealyticum. This is important because ureaplasmas are usually resistant to most antibiotics routinely used to treat lower urinary tract infections. It appears that hypogammaglobulinaemic patients develop less localised and more severe ureaplasmal infections than immunocompetent subjects, which indicates that antibodies are important in controlling the growth of these organisms in the bladder and urethra.

The persistence of mycoplasmas in the urogenital tract of men in the Antarctic

A series of meatal swabs, taken from 17 men over a period of 17 months during their tour at an Antarctic base was examined for mycoplasmas. The number of organisms isolated never exceeded 10(4) and not every specimen from each man yielded mycoplasmas. Nevertheless, Mycoplasma hominis was isolated from 71% and T-mycoplasmas from 59% of the men at some time during their stay. M. hominis persisted in the presence of serum IHA antibody titres of 1/64. Three subjects yielded only M. hominis and one only T-mycoplasmas.Six men had already spent a year at the base when the study began and mycoplasmas were still being isolated from some of them at the end of a 31 month period of isolation. The persistence of mycoplasmas in the male genital tract can therefore be independent of sexual contact. Two modes of persistence are suggested; either a few men act as carriers and reinfect the others by contaminating their environment, or as seems more likely, most men have chronic infections.

Enhanced growth of T-strain mycoplasmas with N-2-hydroxyethylpiperazone-N'-2-ethanesulfonic acid buffer

The small size of T-strain mycoplasma colonies obtained on agar medium has been a drawback to the study of these organisms. The incorporation of 0.05 mN-2-hydroxyethylpiperazine-N'-2-ethanesulfonic acid (HEPES), a new hydrogen ion buffer, into agar medium at pH 6.8 led to the production of colonies at least 60% greater in diameter than those obtained on media without HEPES at pH 6.5 or 6.0. In addition, the colonies often had the "fried-egg" appearance typical of "classical" large-colony-forming mycoplasmas. The addition of HEPES to liquid medium in the presence of 0.1% urea resulted in a slightly higher number of viable organisms and a corresponding increase in ammonia production. Rapid death of the mycoplasmas occurred on continued incubation of the liquid medium cultures even in the presence of HEPES. The larger colony size facilitated the study of hemadsorption and tissue-culture cell adsorption. Preliminary results of such tests in which these phenomena have been demonstrated are presented. The advantages and disadvantages of having larger colonies are discussed, and the terminology of T-strain mycoplasmas is considered in the light of the present findings.