Respiratory
Image Set 16 - (MJP) Mycobacterium tuberculosis (acid-fast stain)
KEY POINTS: Bacilli that are known as acid-fast bacilli due to their atypical staining properties. They are thin, rod-shaped organisms that are strict aerobes and grow slowly, only averaging a new generation every 12-24 hours. Mycobacterium tuberculosis is the predominant cause of TB in humans. Primary TB is rare after infection in adults, but not in young children who often develop primary tuberculosis. Infection is usually isolated to the lungs and recovery from primary TB is evidenced by a visible calcification (with chest film) and an associated lymph node known as a Ghon complex. The Ghon complex can retain viable bacteria and may be involved in reactivation later in life. Reactivation will occur in 10% of patients usually in the apex of the lung and will cause the classic caseous necrosis.
Mycobacterium tuberculosis 01
Mycobacterium tuberculosis 02
Mycobacterium tuberculosis 03
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