Question 1

Shingles, or herpes zoster, is caused by the same virus that causes

Accepted Answer

Shingles is caused by the varicella-zoster virus, which is the same virus that causes chickenpox.

Question 2

Some strains of Papillomavirus are oncogenic due to their ability to

Accepted Answer

Oncogenic strains of Papillomavirus have the ability to integrate into the host cell DNA, which can lead to uncontrolled cell growth and potential development of cancer. The other options are not directly related to the oncogenic properties of Papillomavirus.

Question 3

Which of the following forms of leishmaniasis is typically fatal?

Accepted Answer

Visceral leishmaniasis, also known as kala-azar, is the most severe form of leishmaniasis and can be fatal without treatment. Mucocutaneous and cutaneous forms of leishmaniasis are usually not fatal but can cause disfigurement and disability if left untreated.

Question 4

A man is suffering severe foot pain in the area of what looks like a large wart. He reports he has had the wart for some time, and the pain and swelling have developed slowly. A sample from the lesion shows that the pus contains large cells that stain a golden brown color. The man is likely suffering from

Accepted Answer

The presence of large cells that stain gold in the pus sample indicates the presence of fungi from the dematiaceous group, which includes species that produce dark, pigmented colonies. Chromoblastomycosis is a chronic fungal infection caused by dematiaceous fungi, characterized by wart-like lesions that gradually enlarge and become ulcerated, with pain and swelling. The infection is commonly acquired through skin injuries caused by thorns, wood splinters, or other vegetative matter.

Question 5

A child has a rash on the face, arms, upper legs and torso that is splotchy, and intensifies after being in the sun. The child does not complain of fever or itchiness. The signs and symptoms are consistent with

Accepted Answer

The rash described is consistent with the rash seen in fifth disease, also known as erythema infectiosum. The rash typically appears on the face and then spreads to the trunk and limbs in a splotchy pattern. It can intensify after sun exposure, but the child does not typically have a fever or itchiness. Chickenpox would present with blisters, and roseola would present with a high fever followed by a rash. Cat scratch disease would present with a bump at the site of a cat scratch, and scabies would present with intense itching and small burrow-like bumps.

Question 6

Sporotrichosis is more commonly known as

Accepted Answer

Rose-gardener's disease is a common name for sporotrichosis, which is a fungal infection caused by the Sporothrix schenckii fungus. Scabies, ringworm, white piedra, and herpangina are not related to sporotrichosis.

Question 7

Acyclovir is a chemotherapeutic agent used to treat

Accepted Answer

Acyclovir is primarily used to treat infections caused by the herpes simplex virus (HSV) and varicella-zoster virus (VZV). It does not work against other types of viruses like those that cause smallpox, anthrax, acne, or measles.

Question 8

A child complains of intensely itchy "pimples" on the hands and wrists. The lesions are small inflamed streaks, but do not appear to contain pus. The child's condition may be the result of infection with

Accepted Answer

The intensely itchy "pimples" on the hands and wrists that do not contain pus are likely caused by a parasitic infestation with Sarcoptes scabiei, also known as scabies. The inflamed streaks are a result of the mite burrowing and laying eggs under the skin. Staphylococcus epidermidis is a common skin commensal and would not typically cause an intense itch like this. Sporothrix schenkii is a fungus that can cause skin lesions, but they would not typically be described as inflamed streaks. Pseudomonas aeruginosa can cause infections in immunocompromised individuals and can result in severe skin infections, but it would typically present with pus-filled lesions. Clostridium perfringens is a bacterium that causes gas gangrene and would not typically present as inflamed streaks on the hands and wrists.

Question 9

A small puncture wound on a woman's arm has become swollen, hot to the touch, and intensely painful. There is tissue necrosis, but it is not "gassy," and under the microscope Gram-positive cocci in chains are present. Which of the following microbes is likely to be responsible?

Accepted Answer

Streptococcus pyogenes is known for causing infections that present with symptoms such as swelling, heat, intense pain, and tissue necrosis. The description of Gram-positive cocci in chains is characteristic of Streptococcus species, making Streptococcus pyogenes the most likely culprit.

Question 10

Erythema infectiosum is also known as

Accepted Answer

Erythema infectiosum is commonly known as "fifth disease" due to its classification as the fifth most common childhood rash-causing viral infection. Choices A, B, C, and D refer to other infectious childhood diseases with different symptoms and causes.

Question 11

Common skin warts are the result of infection with

Accepted Answer

Common skin warts are caused by a group of viruses known as human papillomaviruses (HPV).

Question 12

Ultraviolet illumination is the quickest way to diagnose infections of which of the following?

Accepted Answer

Malassezia furfur can be diagnosed using ultraviolet illumination, as it fluoresces under a Wood's lamp, showing a yellow-green color.

Question 13

A pigment produced by an opportunistic pathogen that contributes to tissue damage is

Accepted Answer

Pyocyanin is produced by the opportunistic pathogen Pseudomonas aeruginosa and has been shown to contribute to tissue damage.

Question 14

"Ringworm" is caused by

Accepted Answer

Ringworm, also known as dermatophytosis, is a fungal infection caused by dermatophytes, which are fungi that infect the dead tissue layers of the skin, hair, and nails. It is not caused by parasitic worms, hypersensitivity reactions or immunosuppression due to HIV infection. However, it is possible for ringworm infections to invade deeper layers of the skin in severe cases, but this is not the usual presentation.

Question 15

Which of the following is an INCORRECT pairing?

Accepted Answer

Herpes zoster, also known as shingles, is caused by the varicella-zoster virus (VZV), which is the same virus that causes chickenpox. Genital warts, on the other hand, are caused by human papillomavirus (HPV).

Question 16

Which of the following is/are anti-phagocytic?

Accepted Answer

The answer of Which of the following is/are anti-phagocytic?
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Question 17

Which of the following can cause birth defects?

Accepted Answer

Rubella, also known as German measles, can cause birth defects if a pregnant woman contracts it during the first trimester of pregnancy. The other diseases listed may have complications, but they are not known to cause birth defects.

Question 18

Which of the following bacterial pathogens is an intracellular parasite?

Accepted Answer

Bartonella henselae is an intracellular parasite that can infect and live inside human endothelial cells, causing cat scratch disease and trench fever. The other bacterial pathogens listed are not intracellular parasites and typically infect and cause disease outside of host cells.

Question 19

Which of the following is becoming rarer as a result of childhood vaccinations?

Accepted Answer

Subacute sclerosing panencephalitis, a rare and fatal complication of measles, is becoming rarer as a result of childhood vaccinations.

Question 20

The rash described as "teardrops on rose petals" is characteristic of

Accepted Answer

The phrase "teardrops on rose petals" is often used to describe the appearance of chickenpox rash, where the fluid-filled blisters resemble drops on a red or pink base. Anthrax rash is typically described as a painless, raised, and ulcerated sore, herpes rash presents as grouped vesicles (blisters) on a red base, smallpox rash presents as firm and deeply embedded bumps, and warts may or may not have a distinct appearance depending on the type.

Quiz 19: Microbial Diseases of the Skin and Wounds