Mycobacterium Tuberculosis

1
Mycobacterium Tuberculosis

• Amber Garza
• Kaylee Stroud
• Jennifer Sanchez

2
Patient

• Viper Jackson is an inmate in a New York prison.
  He had complained of a dry, persistent cough and
  saw the doctor where a culture was taken. Later
  the lab reported the presence of acid fast
  bacteria. The culture was sent out and the
  identification came back Mycobacterium
  tuberculosis with resistance to rifampin and INH

3
Specific Term

• M. Tuberculosis is known as Multi Drug Resistant
  Tb (MDR-Tb).

4
Characteristics

• Cell wall composed of mycolic acid, a waxy lipid
  made of 60-90 carbon atoms
• Capable of Intracellular growth
• Are protected from lysis once they are
  phagocytized
• May remain dormant for decades inside macrophages
  and in the centers of tubercles.
• Acid-fast Gram Positive Bacilli
• Has slow growth, divides in hours to days

5
Characteristics Continued

• Hydrophobic
• Can live up to 8 months without a host
• Infects respiratory tract via inhalation of
  respiratory droplets
• Droplets are about 5 um in diameter. Minimum
  infectious dose is about 10 cells.
• Obligate aerobes

6
Resistance

• The resistance to Rifampin is a result of
  chromosomal mutation that alters binding site on
  enzyme (Bauman 305).
• INH (Isonicotinic acid hydrazide) resistance is
  due to random mutations of bacterial chromosomes
  that result in reduced drug uptake or alteration
  of target sites (Bauman 307).

7
DNA Exchange Image found _at_www.genomenewsnetwork.o
rg/articles/11_00/TB.
                               M.
tuberculosis in mouse macrophages. Courtesy
Center for Tuberculosis Research, Johns Hopkins
University

• Courtesy The Rockefeller University

Courtesy The Rockefeller University

• M. Tuberculosis exchanges DNA by forms of
  Transformation. They replicate freely within
  macrophages slowly killing them.

8
Treatment

• Combination of antibiotic therapy consisting of
  strepmycin, ethambutol, and/or pyrazinamide.
• If successful, treatment may take as long as two
  years.
• Dots (directly observe therapy)
• The New York outbreak of 1990 cost over 1
  billion to quell.

9
Prognosis

• 80 mortality rate
• Most likely to die from Lung Disease
• If HIV positive patient will die sooner
• Will die from infection of all other organs once
  M. Tuberculosis spreads

10
Precautions

• Use personal protective gear
• Quarantine
• Monitor treatment and visit doctor frequently