Chapter 3.15 : Detection of Human Mycoplasmas and Ureaplasmas from Clinical Specimens by Culture and PCR

Abstract:

Mycoplasma pneumoniae is a common cause of upper and lower respiratory infections in persons of all ages. Tracheobronchitis is the most common clinical syndrome, but pneumonia commonly occurs and extrapulmonary infections have been described. More detailed information concerning human diseases and clinical aspects of infections caused by M. pneumoniae is available in reference texts and reviews ( 1 , 2 ). Specimens obtained from the upper and lower respiratory tracts are appropriate to culture for the presence of M. pneumoniae. Since the organism has also been known to cause invasive disease in other body sites, it may be appropriate in some circumstances to culture sterile body fluids such as CSF, synovial fluid, or other types of clinical specimens, depending on the type of infection suspected. Growth and presumptive identification of M. pneumoniae can be accomplished by demonstration of glucose utilization in SP4 broth and development of spherical 10- to 100-μm colonies on SP4 agar after 4 to 20 days or more of incubation. Definitive organism identification has been accomplished using a variety of tests such as hemadsorption, tetrazolium reduction, or growth inhibition in the presence of specific antiserum. More recently, the PCR assay has been used to distinguish M. pneumoniae isolated in culture from several species of commensal mycoplasmas that often inhabit the human respiratory tract ( 3 ). Since culture may not detect M. pneumoniae in some specimens and requires several days to weeks to complete, alternative methods such as molecular assays and serologic testing should be considered for optimum detection, even if culture is attempted.