M. Lepre

Question 1

What are the reservoirs for M. leprae?

Answer 1

Humans (Major)

Armadillos (Minor)

Question 2

Why does M. Leprae stick to periphery of humans

Answer 2

Prefers 30C for growth

Question 3

Can you culture M. leprae?

Answer 3

No–14- day doubling time

Question 4

What is paucibacillary leprosy?

Answer 4

= tuberculoid form

Vigorous cell mediated immunity contains disease–CD4+ and Th1

Question 5

What is multibacillary leprosy?

Answer 5

= lepromatous form and is the opposite extreme from paucibacillary leprosy

Inadequate cell mediated immunity–no Th2 and nonprotective antibodies

> 6 lesions infiltrated nodules and plaques–bacilli may be visible on smears from lesion

Symmetric peripheral nerve damage from bacterial growth in schwann cells

Leptromatin PPD - –> because immune response sucks

Question 6

What are peripheral nerve involvement symptoms of M. leprae?

Answer 6

Leads to loss of sensory and motor function:

• ulnar and median nerves–clawed hand
• posterior tibial–plantar insensitivity and clawed toes
• common peroneal–foot drop
• radial cutaneous, facial, and greater auricular nerves

Question 7

What is destroyed in lepromatous form of M. leprae?

Answer 7

Nasal cartilage and can cause eye damage

Question 8

What is found on exam of tuberculoid leprosy?

Answer 8

few sharply demarcated hypo pigmented macules on butt, face, exterior surfaces of limbs

Superficial nerves near lesions may enlarge and be palpable

Neuropathic pain, muscle atrophy

Lepromatin PPD +

Question 9

What is found on exam of lepromatous leprosy?

Answer 9

Extensive bilaterally symmetric cutaneous macules, nodules, plaques, papules

Lesions with poorly-defined boarders and raised centers

Eye infection

Loss of nasal cartilage

Leonine facies–facial skin becomes thickened and corrugated

Lepromatin PPD -

Question 10

Skin smear of lepromatous will show what?

Answer 10

bacilli visible and lipid-laden macrophages–foam cells

Question 11

Skin smear of tuberculoid will show what?

Answer 11

granulomatous changes with epithelial cells and lymphocytes

Question 12

What is the tx for tuberculoid?

Answer 12

Dapsone and rifampin for 2 yrs

Question 13

What is the tx for lepromatous

Answer 13

Dapsone, rifampin, and clofazimine for 2 yrs

Question 14

What can lepromatous pts develop that may require tx using thalidomide?

Answer 14

Erythema nodosum leprosum