Treatment of Leprosy

Question 1

Paucibacillary is the same as?

Answer 1

Tuberculoid leprosy

Question 2

Multibacillary is the same as?

Answer 2

Lepromatous leprosy

Question 3

What is the standard therapy for tuberculoid leprosy?

Answer 3

Dapsone 100mg daily for 12 months
Rifampicin 600mg daily for 12 months

Don’s worry about dose

Question 4

What is the standard therapy for Lepromatous leprosy?

Answer 4

Dapsone 100mg daily for 24 months
Rifampicin 600mg daily for 24 months
Clofazimine 50mg daily

Don’t worry about dose

Question 5

What drug will decrease the clearance of Dapsone?

Answer 5

Probenecid will decrease the renal elimination of

Question 6

What potent chemical effect does Dapsone have?

Answer 6

Dapsone is metabolized to hydoxylamine a potent oxidant –> methemeglobinemia and hemolysis

Question 7

What is the MOA of Dapsone?

Answer 7

Dapsone inhibits dihydropteroate synthase (folate antagonist)

Also functions to inhibits second messengers in neutrophil chemotaxis

Question 8

What is Dapsone syndrome?

Answer 8

A constellation of adverse effects including:

A rash on the upper limbs and forehead
dermatitis –> lymphadenopathy –> hepatitis

Also possible SJS

FYI:
Hemolysis
methemeglobinemia
Hepatitis/cholestatic jaundice
peripheral neuropathy (motor)
severe hypoalbuminemia
psychosis
Leukopenia
agranulocytosis

Question 9

For what three conditions is dapsone primarily indicated?

Answer 9

acne vulgaris
dermatitis herpetiformis
Leprosy (Hansen’s disease)

Question 10

What is the MOA for Rifampin?

Answer 10

Rifampin inhibits bacterial RNA polymerase

Question 11

What is important about the metabolism of Rifampin?

Answer 11

Rifampin is metabolized/eliminated in the liver.

It also is a potent CYP inducer with multiple drug-drug interactions

Question 12

How often should you take rifampin?

Answer 12

Not more than twice weekly

Question 13

What adverse effects are important to remember when prescribing rifampin?

Answer 13

Can cause sever liver toxicity
Complicates diabetes
Discolors body secretions

Question 14

What is the MOA of clofazimine?

Answer 14

Binds to guanine in mycobacterial DNA

- immunosuppression

Question 15

Why does Clofazimine persist for many months in the body?

Answer 15

Because it is highly lipophilic and collects in fatty and reticuloendothelial system.

Question 16

How is clofazimine eliminated?

Answer 16

Clofazimine is eliminated by the liver.

Question 17

Clofazimine has been known to caused some adverse side effects. What are they?

Answer 17

Hepatitis
Staining of body fluids (even in suckling infant)
Feces may appear black or tarry
Skin discoloration may trigger depression.

Question 18

Which conventional antibiotics are used to treat Leprosy?

Answer 18

Clarithromycin: (inhibits 50S ribosomal sub-unit)
Minocycline: (Inhibits 30S ribosomal sub-unit)
Ofloxacin: (inhibits bacterial DNA gyrase)

Question 19

T or F: Minocycline should not be given to pregnant women?

Answer 19

T : Minocycline is Cat D

Question 20

What are type 1 drug reactions?

Answer 20

Red patchy skin lesions, erythema, swollen hands/feet, joint pain

(Irritation of the skin and joints)

Question 21

How are type 1 drug reactions treated?

Answer 21

Corticosteroids

Question 22

What are type 2 drug reactions?

Answer 22

Erythema nodosum leprosum:
sudden eruption of numerous painful nodules with neuritis

Treated with Corticosteroids, Clofazimine, or Thalidomide

Question 23

What is the MOA of Thalidomide?

Answer 23

Inhibits NfkB mediated transcription of TNF-alpha. Helps block leukocyte migration.

Question 24

What is the most important adverse effect of Thalidomide?

Answer 24

Teratogen

Question 25

What are some other ADEs for Thalidomide?

Answer 25

Increased HIV load
somnolence > rash > headache
rarely peripheral neuropathy