Mycoplasma pneumonia

Mycoplasma pneumonia is a form of bacterial pneumonia which is caused by bacteria of the Mycoplasma genus.

Pathophysiology
Mycoplasma pneumoniae is spread through respiratory droplet transmission. Once attached to the mucosa of a host organism, M. pneumonia extracts nutrients, grows and reproduces by binary fission. Attachment sites include the upper and lower respiratory tract, causing pharyngitis, bronchitis and pneumonia. The infection caused by this bacterium is called atypical pneumonia because of its protracted course and lack of sputum production and wealth of extra-pulmonary symptoms. Chronic mycoplasma infections have been implicated in the pathogenesis of rheumatoid arthritis and other rheumatological diseases.

Diagnosis
M. pneumoniae infections can be differentiated from other types of pneumonia by the relatively slow progression of symptoms, a positive blood test for cold-hemagglutinins in 50-70% of patients after 10 days of infection (cold-hemagglutinin-test should be used with caution or not at all since 50% of the tests are false-positive), lack of bacteria in a gram-stained sputum sample, and a lack of growth on blood agar. Mycoplasma atypical pneumonia can be complicated by Stevens-Johnson syndrome, hemolytic anemia, encephalitis or Guillain-Barré syndrome.

Treatment
Second generation macrolide antibiotics, doxycycline and second generation quinolones are effective treatments. Disease from mycoplasma is usually mild to moderate in severity.

History
M. pneumoniae was historically called "Eaton's agent" because it is grown on Eaton's agar.