Dr. Jakeman Flashcards
1
Q
How is TB transmitted?
A
-Via droplet nuclei
2
Q
Signs and symptoms of Latent TB Infection
A
- Live in the body but dormant
- Positive TST and IGRA
- Normal chest Xray
- Negative sputum/cultures
- Pts are not contagious in this phase
3
Q
Diagnosis of primary TB
A
- Physical exam
- Positive TST and IGRA
- Abnormal chest Xray
- Positive sputum and culture smear
4
Q
Treatment regimens for LTBI
A
1) Isoniazid 300mg daily for 9 months
2) Isoniazid 900mg plus Rifapentine 900mg once weekly for 3 months
3) Rifampin 600mg daily for 4 months
5
Q
Advantages of Isoniazid and Rifapentine regimen
A
- Higher completion rates
- Shorter duration
- Less hepatotoxicity
- Given once weekly
6
Q
RIPE Treatment for TB
A
- Rifampin
- Isoniazid
- Pyrazinamide
- Ethambutol
7
Q
Dosing for Rifampin
A
- 10mg/kg/day
- Based on TBW
- Max dose is 600mg/day
8
Q
Dosing for Isoniazid
A
- 5mg/kg/day
- Based on TBW
- Max dose is 300mg/day
9
Q
Dosing for Pyrazinamide
A
- Use IBW
- 40 to 55kg = 1g
- 56 to 75kg = 1.5g
- 76 to 90kg = 2g
- If CrCl < 30ml/min dose 3x/week
10
Q
Dosing for Ethambutol
A
- Use IBW
- 40 to 55kg = 800mg
- 56 to 75kg = 1200mg
- 76 to 90kg = 1600mg
- If CrCl < 30ml/min dose 3x/week
11
Q
Length of initial phase vs continuation phase
A
- Initial phase = 2mo
- Continuation phase = 4-7mo
12
Q
Drug-Drug interactions
A
- Always run an interaction check
- Rifamycins are common inducers (decrease other drugs to sub-therapeutic levels)
- Isoniazid is an inhibitor (Increasing other drugs to toxic levels)
13
Q
Why does mycobacterial resistance occur?
A
- Poor prescribing practices
- Poor treatment programs
- Drug PK/PD issues
- Poor infection control
- Drugs kill susceptible bugs and leave resistant ones
14
Q
Patients at risk for resistant TB
A
- Culture positive after 2 to 4mo of treatment
- Previously treated for TB
- In contact with pt with resistant TB
15
Q
MDR definition
A
- Resistant to isoniazid and rifampin
- The two best first line TB drugs
