Question 1

Tissue necrosis caused by Clostridium perfringens may be distinguished from necrotizing fasciitis in what way?

Accepted Answer

Tissue necrosis caused by Clostridium perfringens is characterized by the presence of Gram-positive, endospore-forming bacilli in the affected area and the emission of foul-smelling gases from the damaged tissue, due to the gas produced by the bacteria as a byproduct of its metabolism.

Question 2

A contributing factor to cutaneous candidiasis might be

Accepted Answer

A shift in the normal microbiota can lead to an overgrowth of Candida on the skin, contributing to cutaneous candidiasis.

Question 3

Cutaneous mycoses usually

Accepted Answer

Cutaneous mycoses are superficial infections that affect the skin, hair, or nails, typically not invading deeper tissues or causing systemic infections.

Question 4

Which of the following skin infections is caused by a protozoan?

Accepted Answer

Leishmaniasis is caused by the protozoan parasites of the genus Leishmania, which are transmitted to humans by the bite of infected female phlebotomine sandflies.

Question 5

What type of infection is shown?

Accepted Answer

The answer of What type of infection is shown? 
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Question 6

The numbers and types of microbes found in the normal skin microbiota are consistent across all body surfaces.

Accepted Answer

The numbers and types of microbes vary significantly across different areas of the skin due to variations in factors such as moisture, temperature, and sebum production.

Question 7

As measles vaccination rates have declined in recent years due to concerns about the vaccine, there have been no documented outbreaks of the disease, showing that the measles virus has been successfully eliminated from the population.

Accepted Answer

Despite high vaccination rates in many areas, measles outbreaks have occurred, particularly in communities with lower vaccination rates. The measles virus has not been eliminated from the population, and declining vaccination rates can lead to increased outbreaks.

Question 8

A hospital burn unit has experienced ongoing problems with pseudomonad infections in multiple wards despite attention to patient hygiene and environmental sanitation. Which of the following would not be a possible source of the bacteria?

Accepted Answer

The hospital cafeteria is unlikely to be a source of pseudomonad infections in a burn unit, as it is not directly involved in patient care or environments where patients with open wounds are treated.

Question 9

Which statement is not true about leishmaniasis?

Accepted Answer

Leishmaniasis is not preventable by a vaccine, as there is currently no vaccine available for leishmaniasis recommended for travelers or for use in endemic areas.

Question 10

A small child presents to the pediatric office with a reddened sclera, itchy eyes, and a watery, clear discharge from the affected eye. The most likely diagnosis is

Accepted Answer

Viral conjunctivitis is characterized by reddened sclera, itchy eyes, and a watery, clear discharge, which matches the symptoms described. Bacterial conjunctivitis typically presents with purulent (pus-like) discharge, and trachoma is a specific type of bacterial infection caused by Chlamydia trachomatis, not indicated by the symptoms described.

Question 11

Which does not apply to ringworm infections?

Accepted Answer

Ringworm infections are not caused by a worm; they are caused by fungi (dermatophytes).

Question 12

Methicillin- resistant Staphylococcus aureus (MRSA) cause the same infections as non- resistant S. aureus stains; however, the bacterium has evolved cell- wall building enzymes which do not bind with methicillin and other beta- lactam antibiotics.

Accepted Answer

MRSA (Methicillin-resistant Staphylococcus aureus) causes the same types of infections as non-resistant S. aureus strains, but it has developed resistance through the alteration of penicillin-binding proteins in its cell wall, which prevents methicillin and other beta-lactam antibiotics from effectively binding and inhibiting cell wall synthesis.

Question 13

The common infection known as "pink eye" is an infection of the

Accepted Answer

Pink eye, medically known as conjunctivitis, is an infection or inflammation of the conjunctiva, the transparent membrane that lines the eyelid and covers the white part of the eyeball.

Question 14

Several forms of keratitis are linked to

Accepted Answer

The answer of Several forms of keratitis are linked to
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Question 15

Which patient group is least susceptible to infections by pseudomonads?

Accepted Answer

The answer of Which patient group is least susceptible to...

Question 16

Even though rubella is a mild, self- limiting disease, vaccination remains important to prevent severe neurological damage to babies whose mothers are exposed to rubella in utero.

Accepted Answer

Rubella, while generally mild in children and adults, can cause congenital rubella syndrome in unborn babies if the mother is infected during pregnancy, leading to serious birth defects including neurological damage. Vaccination is crucial to prevent these outcomes.

Question 17

Which protective mechanism of the eye is incorrectly matched with its description?

Accepted Answer

The conjunctiva is a mucous membrane that covers the front of the eye and lines the inside of the eyelids, not a transparent layer protecting the iris. Its primary function is to protect the eye from external particles, bacteria, and viruses, rather than specifically protecting the iris.

Question 18

While on a medical volunteer trip to an impoverished country, you encounter a patient whose eyelids are turned inward as shown. What is the cause and the best treatment?

Accepted Answer

The answer of While on a medical volunteer trip to...

Question 19

Pyocyanin, a greenish- blue pigment produced by pseudomonads, acts as a virulence factor by

Accepted Answer

Pyocyanin acts as a virulence factor by generating reactive oxygen species, which can damage host tissues and suppress the immune response.

Question 20

Onchocerciasis, or river blindness, is caused by a and is spread via .

Accepted Answer

Onchocerciasis, or river blindness, is caused by a helminth (a parasitic worm) named Onchocerca volvulus and is spread through the bite of infected blackflies.

Quiz 17: Skin and Eye Infections