The name seems to be quite interesting to all, doesn’t it? There will surely be a wonder, whether a bacterium can be fried like an egg or not!!! Fried egg bacteria are actually the characteristic appearance of Mycoplasma.
Mycoplasmas are the smallest free-living microorganisms and belong to the group of bacteria which lack a cell wall and can take up any shape they want to. They are at times mistaken for viruses, as they are permeable through bacterial filters with their flexibility.
They do not have spores and movement appendages like flagella or fimbriae. Some of them seem to be motile by gliding. While growing in artificial culture media, they appear biphasic with the characteristic ‘fried egg’ appearance. Another unique character is their requirement for cholesterol and related sterols for its growth.The colony has a central opaque granular area of growth extending into the depth of the culture medium. It is surrounded by a flat, translucent peripheral zone.
Their growth is inhibited by gold salts, temperature of 450C (15minutes), antibiotics like tetracycline, lipolytic agents such as taurocholate and digitonin.
Mycoplasmas produce surface infections adhering to the mucosa of the respiratory, gastrointestinal and genitourinary tracts. They produce two kinds of infections in humans – pneumonia (also called primary atypical pneumonia) and genital infections. They cause prolonged infections in patients with HIV.
Pneumonia begins after 1-3 weeks of incubation. It starts off with fever, total tiredness, headache, sore throat and cough with bloody sputum. The disease is self-limiting and the patient recovers within 1-2 weeks. Rashes and meningitis are other complications seen along with this.
Transmission of this infection is mainly through nasopharyngeal droplets. Close contact also acts as an important reason to spread. The bacteria can remain in the throat for 2 or more months after recovering from the disease.
Laboratory diagnosis includes;
1. Isolation of Mycoplasma from throat swabs and respiratory secretions
2. PCR assay is carried out when isolation methods become difficult or delayed.
3. Serological methods may be specific or non-specific.
a. Specific methods include immunofluorescence, hemagglutination inhibition and metabolic inhibition tests.
b. Nonspecific tests are Streptococcus MG and cold agglutination tests.
4. Indirect Coomb’s test is also performed in some cases.
The Mycoplasma species obtained from urinary tract of humans are called T form Mycoplasma. They are reclassified as Ureaplasma urealyticum. These are responsible for genital infections.
The transmission is through unsafe sexual contact and lead to urithritis, inflamed anus and the lining of the rectum (proctitis), inflammation of the penis and the foreskin (balanoposthitis), and Reiter’s syndrome (swelling and pain in the joints of knee, ankles and feet accompanied by inflammation of the eyes and urinary tract) in men.
In women; acute salphingitis (inflammation of the Fallopian tube), pelvic inflammatory disease (inflammation of the uterus, Fallopian tube and ovaries), cervicitis (inflammation of the uterine cervix) and vaginitis are common genital infections. Infertility, abortion, low birth weight of the infants, etc. follows.
Treatment
Tetracyclines, erythromycin, macrolide antibiotics and quinolones are widely used to treat mycoplasmal infections. They show resistance to penicillin and cephalosporin. Erythromycin and thallium acetate are effective against Ureaplasma urealyticum.
