tuberculosis

tuberculosis

1. anatomy

   • Each lung has an apex, base, 2 surfaces (costal and medial) and 3 borders (anterior, posterior & inferior).

2. brief introduction

   • M. tuberculosis is part of a complex that has at least 9 members: M. tuberculosis sensu stricto, M. africanum, M. canetti, M. bovis, M. caprae, M. microti, M. pinnipedii, M. mungi, and M. orygis
     • It requires oxygen to grow, does not produce spores, and is nonmotile.[8][9] M. tuberculosis divides every 15–20 hours. This is extremely slow compared with other bacteria, which tend to have division times measured in minutes
       • It is a small bacillus that can withstand weak disinfectants and can survive in a dry state for weeks. Its unusual cell wall is rich in lipids such as mycolic acid and is likely responsible for its resistance to desiccation and is a key virulence factor
         • the mycolic acid in the cell wall of M. tuberculosis does not absorb the stain. Instead, acid-fast stains such as Ziehl-Neelsen stain, or fluorescent stains
           • commonly used media include liquids such as Middlebrook 7H9 or 7H12, egg-based solid media such as Lowenstein-Jensen

3. clubbing causes

   • copd, lung cancer, ulcerative colitis, bronchiectasis, infective endocarditis, GI distress

4. mode of transmission

   • Indirect contact
     • When you touch a doorknob handled by someone ill with the flu or a cold, for example.
   • Insect bites
     • Some germs rely on insect carriers — such as mosquitoes, fleas, lice or ticks.
   • Food Contamination
     • such as undercooked hamburger or unpasteurized fruit juice.
   • droplet
     • Transmission occurs when droplets containing microorganisms generated during coughing, sneezing and talking are propelled through the air.
   • Airborne
     • Microoganisms carried in this manner remain suspended in the air for long periods of time and can be dispersed widely by air currents. Because of this, there is risk that all the air in a room may be contaminated