Drugs for TB + updates on TB guidelines

Question 1

What comprises the complex lipid in M. tuberculosis

Answer 1

Mycolic acid, cord factor, Wax D

Question 2

Other name of cord factor

Answer 2

Serpentine factor

Question 3

What type of hypersensitivity is shown in mantoux test

Answer 3

Type IV/delayed type

Question 4

When is a cutoff of 5mm in mantoux test considered positive

Answer 4

immunocompromised, close contact with TB positive, with clinical signs of TB, chest x-ray shows fibrotic changes

Question 5

When is a cutoff of 10mm in mantoux test used

Answer 5

persons with injection drug use, people in high-risk places, children <4

Question 6

When is a person classified as tb new case

Answer 6

never been treated for TB / taken anti-TB drugs for < 1 month

Question 7

TB retreatment - relapse

Answer 7

previously treated, declared cured/treatment completed, now diagnosed with recurrent TB

Question 8

Diagnostic algorithm for TB (prev guidelines)

Answer 8

with signs -> smear -> CXR if smear neg -> gene Xpert if CXR pos to show resistance to rif

Question 9

Mechanism of resistance of isoniazid

Answer 9

Mutations in KatG gene

Question 10

MOA of isoniazid

Answer 10

Inhibition of mycolic acid synthesis

Question 11

MOA of rifampicin

Answer 11

Interferes withRNA polymerase

Question 12

Mechanism of resistance of rifampicin

Answer 12

Mutation in rpoB gene

Question 13

What is the active form of pyrazinamide that decreases the pH of the M. tuberculosis cell

Answer 13

Pyrazinoic acid

Question 14

MOA of ethambutol

Answer 14

Inhibits arabinosyl transferase

Question 15

MOA of streptomycin

Answer 15

Inhibits translation during protein synthesis

Question 16

What does sterilizing activity of anti-TB drugs mean

Answer 16

Drug can kill all organisms - even those not actively multiplying

Question 17

What are the only anti-TB drugs with sterilizing activity

Answer 17

Rifampicin, Pyrazinamide

Question 18

What anti-TB drug kills intracellular bacilli only

Answer 18

Pyrazinamide

Question 19

What is the only bacteriostatic anti-TB drug

Answer 19

Ethambutol

Question 20

What anti-TB drug kills extracellular bacilli only

Answer 20

Streptomycin

Question 21

How to prevent isoniazid-induced peripheral neuropathy

Answer 21

Vitamin B6 (pyridoxine)

Question 22

What drug causes red orange urine discoloration

Answer 22

Rifampicin

Question 23

ADR of pyrazinamide

Answer 23

Hyperuricemia

Question 24

ADRs of streptomycin

Answer 24

nephrotoxicity, ototoxicity, vestibulotoxicity

Question 25

What novel anti-TB drug inhibits a complex of the electron transport chain

Answer 25

Bedaquline

Question 26

MOA of delamanid

Answer 26

Disruption of mycobacterial cell wall synthesis

Question 27

What is the next step after classifying a case as presumptive TB

Answer 27

Gene Xpert

Question 28

What is not included in the first-line TB drugs in the updated TB treatment regimen

Answer 28

Streptomycin

Question 29

What is Regimen 1 composed of and who is it for

Answer 29

2HRZE/4HR
TB except cns, bones, joints that is not rif resistant

Question 30

What is Regimen 2 composed of

Answer 30

2HRZE/10HR

Question 31

What comprises SSOR

Answer 31

4-6 months; Lfx-Bdq-Cfz-Pto-E-Z-HdH
5 months: Lfx-Cfz-E-Z

Question 32

What is included in the exclusion criteria for SSOR

Answer 32

Disseminated TB/Intractable TB
FQ resistance
Exposure to Lfx/Cfz/Pto for >1 month
Heart disease
QT >500ms
Chronic hepatitis (AST/ALT >5x elevated)
Chronic renal insufficiency (crea clearance <20)

Question 33

Additional exclusion criteria for SLOR FQS

Answer 33

Exposure to Lzd >1 month
Severe anemia (hgb <8)

Question 34

What lab test to request if giving delamanid

Answer 34

serum albumin

Question 35

SLOR FQ-S

Answer 35

6 months: Lfx-Bdq-Lzd-Cfz
12-14 months: Lfx-Lzd-Cfz

Question 36

SLOR FQ-R

Answer 36

6 months: Lzd-Bdq-Dlm-Cfz-Cs
12-14 months: Lzd-Cfz-Cs