What is different about mycobacteria from other types of bacteria?
It is neither gram positive or gram negative due to staining issues.
Mycobacteria are irregular-shaped __________, and are __________ bacteria.
Bacilli
Aerobic
Mycobacterial membrane are rich in lipids, including __________ and __________.
Mycolic acid
Waxes
Why is it necessary for prolonged treatment of mycobacterium?
They cause chronic disease by growing slowly
They become dormant in hosts for long periods of time.
Describe several ways treatment of mycobacteria can be difficult.
Efflux pumps
Drugs don't penetrate the cell wall
They reside within host cells.
In __________tuberculosis, mycobacterium tuberculosis is phagocytized by __________, and multiply intracellularly. After __________ weeks, the immune system attacks, forming __________, granulomas consisting of a central core containing bacilli surrounded by __________.
Primary
Macrophages
3-4 weeks
Tubercles
Leukocytes
What happens to a TB tubercle if it breaks down into necrotic lesions?
They heal by calcification.
Secondary TB occurs when tubercles expand and drain into the __________ & __________.
Bronchial Tubes
Upper Respiratory Tract
What gradually worsening symptoms can one see with secondary TB?
Violent Coughing
Green and Bloody Sputum
Fever, Fatigue
Anorexia, Weight-loss
First-treatment for active TB infection includes what drugs?
Isoniazid + Rifampin + Pyrazinamide + Ethambutol
Secondary TB can be treated with which drugs?
Isoniazid
Isoniazid + Rifapentine (combo)
Rifampin
What other agents are available for the treatment of resistant TB bacteria?
Rifabutin
Rifapentine
Clofazimine
Dapsone
What is isoniazid's MOA?
It inhibits mycolic acid synthesis.
How can isoniazid be both bacteristatic and bactericidal?
It kills rapidly dividing cells.
Mutations in the catalase-peroxidase enzyme can create bacterial reistance to __________.
Isoniazid
What are some common side effect's of isoniazid?
Rash
Fever
Jaundice
Peripheral Neuritis
T/F: Isoniazid can have potential neurotoxicity with patient's with seizure disorders.
True, it can cause convulsions.
Isoniazid is commonly administered with __________, to prevent peripheral neuritis and CNS toxicity.
Pyridoxine
__________ binds RNA polymerase and inhibits transcription initiation.
Rifampin
T/F: Rifampin is bactericidal to gram positive bacteria only.
False, gram negative as well.
Why is resistance to rifampin common?
Mutations in RNA polymerase
Even though rifampin is generally well-tolerated, why is taking it a concern?
It heavily induces several CYP enzymes, causing decreased levels of several drugs.
Pyrazinamine inhibits __________, and is only active in __________.
Mycolic Acid Synthesis
Acidic pH
Ethambutol inhibits __________, thereby inhibiting __________ in mycobacterium.
Arabinosyl Transferase
Cell Wall Synthesis
Mycobacterium avium complex is an __________ infection and is commonly found in __________ patients.
Opportunistic
AIDS
Prophylactic treatment of mycobacterium avium complex involves which drugs?
Azithromycin and Clarithromycin (both macrolides)
Other than macrolides, first-line treatment of mycobacterium avium consists of what other drugs?
Ethambutol
Rifabutin
The two major forms of leprosy are __________ & __________.
Tuberculoid
Lepromatous
Treatment of tuberculoid leprosy involves combination therapy with __________ & __________. Adding __________ is warranted for treatment of lepromatous leprosy.
