Tuberculosis (Exam 1b) Flashcards
Tuberculosis
-Any infection caused by bacteria mycobacterium
-MTB is aerobic bacillus - rod - shaped and need lots of O2 to grow and proliferates –> why it is most common in the lungs
Tuberculosis: Characterized by
- granulomas in the lungs –> nodular accumulations of inflammatory cells
Transmitted via humans, cattle or birds
Tubercle bacilli are transmitted in
AIRBORNE Droplets expelled by infected people or animals
Tuberculosis is slow or fast growing organisms
very slow making it harder to treat
Infectious TB
-For those with normal immune system exposed to TB, the bacteria is usually contained by the immune/inflammatory system called LATENT TB infection –> not clinical evidence of disease
-Sometimes even when a person becomes infected the bacilli are isolated in those granulomas (Tubercles) and it remains dormant for life
If persons immune system is impaired, reactivation of the bacteria can occur and can spread throughout the body HIV, immunosuppressive mediations, poor nutritional status, and renal failure are common reactivators
Active TB Symptoms
Fatigue
Weight loss
Lethargy
Low-grade fever (Afternoon)
Nigh sweats (more addictive)
Anxiety
Productive cough
Later in the disease dyspnea, chest pain and hemoptysis can occur
Extrapulmonary TB
Neurologic deficits, meningitis symptoms, bone pain, urinary problems
Screening and Diagnosis
High risk populations
Interferon gamma release assay (blood draw)
Non high risk –> TB skin test
Confirm through a sputum stain and culture and look for the granulomas on CXR
Pharmacology for TB
Isoniazid
Rifampin
Ethambutol
Pyrazinamide
Streptomycin
Antitubercular Drugs
Treat all infections caused by the mycobacterium organism
FIrst (what we learn) and Second line categories
Isoniazid (INH)
Most widely used TB medications (First line)
isoniazid: MOA
Disrupts cell wall synthesis essential functions of mycobacteria given PO
isoniazid: SE
-Peripheral neuropathy
-hepatotoxicity
-optic neuritis/visual disturbances
Isoniazid: NSG consideration
Do not give in patients with liver failure
Avoid antacids — Reduces drug absorption
Given with rifampin (can increase CNA and hepatotoxicity symptoms)
Given with phenytoin, can increase the effects
Isoniazid: BBW
Increase risk of hepatitis –> often given with pyridoxine (vitamine B6)
Rifampin
First line used for lost of mycobacterial infections and other clinical uses
Rifampin: MOA
Inhibits protein synthesis via attacking the hydrocarbon ring structure of mycobacteria
Rifampin: SE
Hepatitis
RED BROWN discoloration of the urine and other body fluids
Rifampin: NSG consideration
CYP inducer
Decrease the effects
Ethambutol
First line basteriostatic
Ethambutol: MOA
Diffusing into the mycobacteria and suppresses RNA synthesis, which inhibits protein synthesis
Ethambutol: SE
Retrobulbar neuritis and blindness
Ethambutol: NSG considerations
Give in combo with INH and rifampin (one in three pill)
Not for children less than 13
Pyrazinamide (PZA)
Bacteriostatic or bactericidal depending on drug concentration
PZA: MOA
Unknown: thought to inhibit lipid and nucleic acid synthesis
PZA: SE
Hepatotoxicity and Hyperuricemia
PZA: Contraindicated
in severe hepatic disease or acute gout (high uricemia levels)
not for pregnant people in US
Streptomycin
First ever drug for TB
Streptomycin: TB
aminoglycoside –> interfering with normal protein synthesis causing production of faulty proteins within the bacteria
Streptomycin: SE
Ototoxicity
Nephrotoxicity
Blood Dyscrasias (bleeding times increase)
Streptomycin is
IM only and daily
Drug Resistant TB
-More of issue with HIV and AIDS community. Affects high risk community (PPS)
-MDR-TB
-Asian and Hispanic immigrants i the US are high risk
