A group of mycobacteria which differ in their growth characteristics from Mycobacterium tuberculosis but which they resemble in being acid-fas t. The atypical mycobacteria are also known as the PotentiallyPathogenic Environmental Mycobacteria (P.P.E.M.). They can cause a spectrum of human disease which in some cases can resemble tuberculosis. Mostly they cause disease in immunologically compromi sed humans such as those suffering from AIDS.
The atypical mycobacteria. The commonest PPEM to cause human disease is the Mycobacterium avium-intracellulare complex. PPEM differ from M. tuberculosis in their source (environmental or zoonotic), rate of growth, temperature of growth and ability to produce pigment on culture. Mostly infect immunologically compromised humans and the disease caused by some species may be clinicallyindistinguishable from true human tuberculosis.... potentially pathogenic environmental mycobacteria (ppem)
any one of a group of community-acquired *pneumonias that do not respond to penicillin but do respond to such antibiotics as tetracycline and erythromycin. They include infection with Mycoplasma pneumoniae, Chlamydia psittaci (see psittacosis), and Coxiella burnetii (see Q fever).... atypical pneumonia
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