Tuberculosis Flashcards
Cause of Tuberculosis
Mycobacterium tuberculosis
Transmission of Tuberculosis
- spread person to person by droplet nuclei through the air
- produced when a person coughs, sneezes, speaks, or sings
MUST HAVE PULMONARY OR LARYNGEAL TUBERCULOSIS TO SPREAD
Key Points
- you cannot get TB from eating or drinking after someone
- you cannot get TB from dishes, utensils, clothing, or linens
- you do not need to wear gloves, caps, gowns
- there is not much more risk with flying
Pathogenesis
tubercle bacilli is inhaled through the nose or mouth –> carried down the trachea into the lung by droplet nucleus –> once reaching alveoli, they multiply freely for 2 to 10 weeks –> bacilli can then spread unopposed from the initial location (lung) to the lymph nodes in the chest –> from the lymphatic system, the bacilli can spread to other parts of the body through the blood stream
Susceptible Areas to TB Downstream
upper portions of lungs
kidneys
spine
brain
bone
Latent TB
- bacilli in the body
- positive skin test/TGRA
- normal chest xray
- no symptoms
- negative sputum
- infected: yes
- infectious: no
5-10% of patients will develop active TB
Active TB
- bacilli in the body
- positive skin test/IGRA
- abnormal chest xray
- symptoms present
- positive sputum
- infected: yes
- infectious: yes
Epidemiology
- second leading cause of death due to infectious disease in the world
- Hot spots: sub-saharan Africa, India, South Asia
- in 2019, the 30 high TB burden countries accounted for 87% of new TB cases
Resistant Strains
- becoming resistant to almost all standard treatment
- the multidrug and extreme resistant cases must be treated by TB experts
Countries leading TB Cases
- India
- Indonesia
- China
- Philippines
- Pakistan
- Nigeria
- Bangladesh
- South Africa
Clinical Presentation
- 70-80% of the infections involve the lungs
- cough, fever, hemoptysis, weight loss (anorexia), night sweats
HEMOPTYSIS DISTINGUISHES SYMPTOMS OF TB FROM THE FLU
Drug Therapy
Latent:
- Isoniazid x 9 months
- Isoniazid + Rifapentine x 12 weeks
- Rifampin x 4 months
Active:
- Isoniazid + Rifampin + Ethambutol + Pyrazinamide x 2 months then Isoniazid + Rifampin x 4-7 months
FOR ACTIVE TB, DIRECT OBSERVED THERAPY FOR 6-9 MONTHS
Cost of Treatment
Drug Sensitive: $49,000
MDR-TB: $393,000
XDR-TB: $758,000
Rifampin ADR & Monitoring Parameters
ADR:
- hepatotoxicity
- lupus like syndrome
- peripheral neuropathy
- monoamine toxicity
Monitoring:
- LFT
- flushing & tingling in hands/feet
Isoniazid ADR & Monitoring Parameters
ADR:
- hepatotoxicity
- flu like syndrome
- GI upset
- hemolytic anemia
- thrombocytopenia
- renal failure
- orange/discoloration of body fluids
Monitoring:
- LFT, CBC, SCr
