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Margaret R. Hammerschlag

, MD, State University of New York Downstate Medical Center

Last full review/revision May 2021| Content last modified May 2021
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Mycoplasmas are bacteria that cause infections in the respiratory tract and the urinary and genital tracts.

Mycoplasmas are different from other bacteria because they do not have cell walls. Many antibiotics, such as penicillin, kill bacteria by weakening cell walls. Because Mycoplasmas do not have cell walls, many antibiotics cannot kill them.

Symptoms of Mycoplasmas

Symptoms of pneumonia due to M. pneumoniae are typically mild, including low-grade fever, tiredness, sore throat, and cough. This infection is sometimes called "walking" pneumonia, which is a nonmedical term for mild pneumonia that does not require bedrest or hospitalization. Some people even feel well enough to go to work and participate in other daily activities. However, M. pneumoniae sometimes causes a more serious pneumonia that requires hospitalization.

Many people with urinary and genital infection with mycoplasma, especially women, have no symptoms. When symptoms are present, they are similar to those of urinary and genital infection with chlamydia and vary by sex and location of infection:

  • Women may have an abnormal vaginal discharge or a burning sensation while urinating.

  • Men may notice a burning sensation while urinating and sometimes a discharge from the penis.

Diagnosis of Mycoplasmas

  • Nucleic acid amplification tests

Mycoplasmas can sometimes be identified by doing nucleic acid amplification tests (NAATs) on respiratory secretions or on vaginal or urethral swabs. NAATs look for an organism's unique genetic material, its DNA or RNA (which are nucleic acids). NAATs use a process that increases the amount of the bacteria's DNA or RNA so that it can be more easily identified.

Prevention of Mycoplasmas

As with other respiratory infections, prevention includes covering the mouth when coughing or sneezing and washing hands often with soap and water.

There is no vaccine for M. pneumoniae infections.

Treatment of Mycoplasmas

  • Antibiotics

Mycoplasmal infections are treated with antibiotics such as azithromycin, doxycycline, or, sometimes, levofloxacin or moxifloxacin.

More Information

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Chlamydial Infections and Mycoplasmas
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