Mycoplasma pneumonia

Mycoplasma pneumonia
Classification and external resources
ICD-10	B96.0
ICD-9	483.0
MedlinePlus	000082
eMedicine	emerg/467
MeSH	D011019

Mycoplasma pneumonia (also known as "walking pneumonia" because its patients can sometimes continue to walk about whilst suffering from its symptoms) is a form of bacterial pneumonia which is caused by the bacteria species Mycoplasma pneumoniae.

Pathophysiology

Mycoplasma pneumoniae is spread through respiratory droplet transmission. Once attached to the mucosa of a host organism, M. pneumoniae 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.

Mycoplasma atypical pneumonia can be complicated by Stevens-Johnson syndrome, hemolytic anemia, encephalitis or Guillain-Barré syndrome.

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.

PCR has also been used.^[1]

Treatment

Second generation macrolide antibiotics (e.g. erythromycin), doxycycline and second generation quinolones are effective treatments.

References

1. ^ Waris ME, Toikka P, Saarinen T, et al. (November 1998). "Diagnosis of Mycoplasma pneumoniae pneumonia in children". J. Clin. Microbiol. 36 (11): 3155–9. PMC 105292. PMID 9774556. http://jcm.asm.org/cgi/pmidlookup?view=long&pmid=9774556.