Skin VIII

Question 1

define amastigote vs. promastigote

Answer 1

• amastigote = form lacking flagella
• promastigote = a flagellate stage bearing a single, free flagellum but no undulating membrane

Question 2

Leishmaniasis is a parasitic disease spread by ___

Answer 2

Leishmaniasis is a parasitic disease spread by sandflies

Question 3

Leishmania is a genus of ____

Answer 3

Leishmania is a genus of trypanosomes

Question 4

the infective stage of Leishmania is the ____ stage

Answer 4

the infective stage of Leishmania is the promastigote stage

Question 5

when diagnosing Leishmania, ___ are found in the blood samples

Answer 5

when diagnosing Leishmania, amastigotes are found in the blood samples

Question 6

describe the clinical presentation of Leishmaniasis

Answer 6

• cutaneous leishmaniasis (most common) causes skin sores
• visceral leishmaniasis, which affects several internal organs (usually spleen, liver and bone marrow)

Question 7

describe the diagnosis of leishmaniasis

Answer 7

diagnostic stage = amastigotes

• macrophages contain the amastigotes
  
  • 1-5 um long
  • large nucleus
  • small, rod-shaped kinetoplast

Question 8

describe the classification tree of helminths

Answer 8

Question 9

Loa loa affect the ____ and ____ layers of the skin

Answer 9

Loa loa affect the dermis and subcutaneous skin layers

Question 10

the infective stage of Loa loa is the ____ stage

Answer 10

the infective stage of Loa loa is the L3 stage

Question 11

Loiasis causes red itchy swellings, called ____ on the forearms, wrists, sometimes face, breasts or legs

Answer 11

Loiasis causes red itchy swellings, called Calabar swellings on the forearms, wrists, sometimes face, breasts or legs

Question 12

in Loiasis, migration of an adult worm to ____ (___) is commonly seen

Answer 12

in Loiasis, migration of an adult worm to the eyes (subconjunctival) is commonly seen

Question 13

dead worms in Loiasis can cause chronic ____ with the formation of ____ and fibrosis

Answer 13

dead worms in Loiasis can cause chronic abscesses with the formation of granulomatous reactions and fibrosis

Question 14

____ are the diagnostic stage of Loiasis

Answer 14

microfilariae are the diagnostic stage of Loiasis

Question 15

diagnosis of Loiasis is identification of adult worms from ___ or worm removal from ____

Answer 15

diagnosis of Loiasis is identification of adult worms from tissue samples or worm removal from the eye

Question 16

describe antigen immunoassay use for Loiasis

Answer 16

• limited value because of cross-reactivity between filaria and other helminths
• positive serological test does not distinguish between past and current infection

Question 17

a positive serological test for Loiasis does not ____

Answer 17

a positive serological test for Loiasis does not distinguish between past and current infections

Question 18

the organism causing Onchocerciasis is ____

Answer 18

the organism causing Onchocerciasis is Onchocerca volvulus

Question 19

the vector for Onchocerciasis is the ____

Answer 19

the vector for Onchocerciasis is the blackfly

Question 20

Onchocerciasis is also called the ____

Answer 20

Onchocerciasis is also called the blinding filaria

Question 21

Onchocerciasis infections involve the ___ and ___ where adults gather ____

Answer 21

Onchocerciasis infections involve the dermis and subcutaneous tissues where adults gather within nodules

Question 22

the ___ are the infective stage

the ___ are the diagnostic stage

Answer 22

the L3 larvae are the infective stage

the microfilariae arethe diagnostic stage

Question 23

in the mild form of onchocerciasis, there is localized ____ with ___

Answer 23

in the mild form of onchocerciasis, there is localized maculopapular rash with itching

Question 24

Onchocerciasis may heal with ____

Answer 24

Onchocerciasis may heal with hyperpigmentation

Question 25

in a long-standing infection of onchocerciasis, there is destruction of ____ which makes the skin look \_\_\_\_

Answer 25

in a long-standing infection of onchocerciasis, there is destruction of **elastic fibers in the skin** which makes the skin look **thin and wrinkled**

Question 26

onchocerciasis causes severe \_\_\_\_, more so than Loiasis

Answer 26

onchocerciasis causes severe **sight impairment**, more so than Loiasis

Question 27

\_\_\_\_ (a bacterium) is essential for the fertility of the worm in Onchocerciasis

Answer 27

**Wolbachia pipentis** (a bacterium) is essential for the fertility of the worm in Onchocerciasis

Question 28

when the worms die, ____ is released, triggering a host response that causes ____ and can \_\_\_\_\_

Answer 28

when the worms die, **Wolbachia pipentis** is released, triggering a host response that causes **intense itching** and can **destroy nearby tissues**

Question 29

which organism causes the condition seen in the images?

Answer 29

**Onchocerca volvulus**

Question 30

in Onchocerciasis, skin snips are immersed in normal saline and after 24 hours, ___ can be seen swimming free

Answer 30

in Onchocerciasis, skin snips are immersed in normal saline and after 24 hours, **microfilariae** can be seen swimming free

Question 31

Mansonellosis is caused by \_\_\_\_\_

Answer 31

Mansonellosis is caused by **Mansonella streptocerca**

Question 32

microfilariae in Mansonellosis have a distinctive ____ shape to the tail

Answer 32

microfilariae in Mansonellosis have a distinctive **walking stick** shape to the tail

Question 33

Mansonellosis causes chronic ____ often with \_\_\_\_

Answer 33

Mansonellosis causes chronic **papular lesions** often with **post-inflammatory hyperpigmentation**

Question 34

which organism is seen in the image?

Answer 34

Question 35

Trichinosis is caused by ____ which is a ____ (classification)

Answer 35

Trichinosis is caused by **Trichienlla spiralis** which is a **nematode**

Question 36

Trichinosis is characterized by ____ stage in the muscles

Answer 36

Trichinosis is characterized by **encysted larval stage** in the muscles

Question 37

Trichinosis is caused by eating \_\_\_\_, most commonly ____ and also \_\_\_\_

Answer 37

Trichinosis is caused by eating **undercooked meat**, most commonly **pigs** and also **bears**

Question 38

Trichinosis begins with ____ infection causing \_\_\_\_

Answer 38

Trichinosis begins with **intestinal** infection causing **diarrhea, abdominal pain, vomiting**

Question 39

after the intestinal infection in Trichinosis, there is ___ migration into ____ tissues causing \_\_\_\_

Answer 39

after the intestinal infection in Trichinosis, there is **larval** migration into **muscle** tissues causing **periorbital and facial edema, conjunctivitis, fever, myalgias, splinter hemorrhages, rashes and blood eosinophilia**

Question 40

Trichinosis can occasionally be life-threatening, causing \_\_\_\_

Answer 40

Trichinosis can occasionally be life-threatening, causing: ## Footnote **myocarditis, CNS involvement, pneumonitis**

Question 41

what is seen in the image?

Answer 41

Larvae of Trichinella spiralis in nurse cells within striated muscle

Question 42

what is seen in the image?

Answer 42

Larvae of Trichinella, freed from their cysts

Question 43

cutaneous larva migrans is most commonly caused by \_\_\_\_

Answer 43

cutaneous larva migrans is most commonly caused by **Ancylostoma braziliense**

Question 44

the clinical presentation of cutaneous larva migrans is ___ which appears 1-5 days after skin penetration (larva stage)

Answer 44

the clinical presentation of cutaneous larva migrans is **creeping eruption** which appears 1-5 days after skin penetration (larva stage)

Question 45

cutaneous larva migrans is characterized by a \_\_\_, ____ track in the skin associated with intense ___ and mild \_\_\_\_

Answer 45

cutaneous larva migrans is characterized by a **serpiginous**, **erythematous** track in the skin associated with intense **itchiness** and mild **swelling**

Question 46

diagnosis of cutaneous larva migrans is based on ___ and ___ is not recommended

Answer 46

diagnosis of cutaneous larva migrans is based on **characteristic skin lesions** and **biopsy** is not recommended

Question 47

what condition is seen in the image?

Answer 47

Question 48

what condition is seen in the image?

Answer 48

Question 49

what condition is seen in the image?

Answer 49

Question 50

cutaneous larva migrans is acquired when the ___ penetrate unprotected skin

Answer 50

cutaneous larva migrans is acquired when the **filariform larva** penetrate unprotected skin