Question 1

Which factor may influence the specific types of microbes found on the skin?

Accepted Answer

A)  moisture levels 
B)  hormones 
C)  hormones, moisture levels, and soap and cosmetics usage 
D)  moisture levels and soap and cosmetics usage 
E)  soap and cosmetics usage 
A)  moisture levels 
B)  hormones 
C)  hormones, moisture levels, and soap and cosmetics usage 
D)  moisture levels and soap and cosmetics usage 
E)  soap and cosmetics usage C

Question 2

Describe and contrast three types of bacterial skin infections that can lead to tissue necrosis and death. Name and characterize the causative bacteria, and describe epidemiological and clinical features of each disease.

Accepted Answer

Necrosis is tissue death and is usually caused by reduced blood flow to an area. Several bacterial infections can result in localized or spreading tissue necrosis. Necrotizing fasciitis is often caused by Streptococcus pyogenes, also known as Group A streptococci (GAS). S. pyogenes produces a number of virulence factors such as hyaluronidase and lipase that break down tissue and facilitate the spread of the bacteria. M protein on the surface of the bacterium serves as a binding site for plasminogen which triggers a tissue degradation cascade. Gas gangrene is caused by Clostridium perfringens, a soil bacterium which may infect deep wounds. The low- oxygen environment of deep wounds stimulates the growth of the anaerobic clostridia which produces toxins which can lead to rapid tissue death. Cutaneous anthrax is caused by Bacillus anthracis, a bacterium found in soil and often transmitted to human through contact with infected animals or their parts. The bacteria may enter skin abrasions to form a solid, blackened skin nodule. Exotoxins kill first superficial then deeper skin cells. In most cases, the damage stays localized, but prompt treatment is required.

Question 3

Most fungal skin infections are likely to remain superficial except in individuals who are immunocompromised.

Accepted Answer

A) True 
 B)False  True

Question 4

Cutaneous mycoses usually

Accepted Answer

A)  are superficial infections on the skin, hair, or nails. 
B)  are not associated with changes in the normal microbiota. 
C)  are invasive with a considerable risk of fatality. 
D)  occur in the deeper dermal layers or in muscles. 
E)  respond quickly to treatment with a single dose of topical antifungal medication. 
A)  are superficial infections on the skin, hair, or nails. 
B)  are not associated with changes in the normal microbiota. 
C)  are invasive with a considerable risk of fatality. 
D)  occur in the deeper dermal layers or in muscles. 
E)  respond quickly to treatment with a single dose of topical antifungal medication.

Question 5

Which statement describes an important similarity between chickenpox and smallpox?

Accepted Answer

A)  Vaccinations against both are recommended for all children. 
B)  Both have a similar mortality rate of about 30%. 
C)  Both involve the formation of a vesicular rash. 
D)  Both are caused by viruses which lie dormant in nerve cells and be reactivated later in life. 
E)  Both are treatable with antiviral therapy. 
A)  Vaccinations against both are recommended for all children. 
B)  Both have a similar mortality rate of about 30%. 
C)  Both involve the formation of a vesicular rash. 
D)  Both are caused by viruses which lie dormant in nerve cells and be reactivated later in life. 
E)  Both are treatable with antiviral therapy.

Question 6

Which factor is not a reason Propionibacterium acnes (P. acnes) is often associated with acne?

Accepted Answer

A)  increased oxygen levels in clogged pores favoring bacterial growth 
B)  biofilm formation by P. acnes in pores and glands 
C)  increased sebum production during adolescence 
D)  the inflammatory responses to P. acnes which causes pustules and cysts 
E)  the ability of P. acnes to metabolize sebum 
A)  increased oxygen levels in clogged pores favoring bacterial growth 
B)  biofilm formation by P. acnes in pores and glands 
C)  increased sebum production during adolescence 
D)  the inflammatory responses to P. acnes which causes pustules and cysts 
E)  the ability of P. acnes to metabolize sebum

Question 7

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

A)  neonatal bacterial conjunctivitis; antibiotic or silver drops should have been given at birth 
B)  onchocerciasis (river blindness); doxycycline 
C)  viral conjunctivitis; no treatment but the condition will resolve with time 
D)  Acanthamoeba; corneal transplant will likely be necessary 
E)  trachoma; single dose of oral azithromycin 
A)  neonatal bacterial conjunctivitis; antibiotic or silver drops should have been given at birth 
B)  onchocerciasis (river blindness); doxycycline 
C)  viral conjunctivitis; no treatment but the condition will resolve with time 
D)  Acanthamoeba; corneal transplant will likely be necessary 
E)  trachoma; single dose of oral azithromycin

Question 8

Which does not apply to ringworm infections?

Accepted Answer

A)  caused by a worm 
B)  caused by members of the normal skin biota 
C)  can be acquired by direct or indirect contact 
D)  may occur on the feet, groin, scalp, nails, or body 
E)  may manifest as a round skin lesion with a scaly red margin 
A)  caused by a worm 
B)  caused by members of the normal skin biota 
C)  can be acquired by direct or indirect contact 
D)  may occur on the feet, groin, scalp, nails, or body 
E)  may manifest as a round skin lesion with a scaly red margin

Question 9

In streptococcal toxic shock syndrome, pathology results from toxins in the bloodstream which may cause both a red skin rash, as well as

Accepted Answer

A)  release of foul- smelling gases from the infection site. 
B)  a decrease in blood pressure leading to organ failure. 
C)  formation of a blue- or green- colored pus. 
D)  degradation of connective tissue. 
E)  peeling away of the epidermal layer of skin. 
A)  release of foul- smelling gases from the infection site. 
B)  a decrease in blood pressure leading to organ failure. 
C)  formation of a blue- or green- colored pus. 
D)  degradation of connective tissue. 
E)  peeling away of the epidermal layer of skin.

Question 10

Which factor, beginning in 1995, is responsible for the decline in chicken pox from a routine childhood disease to a rare infection?

Accepted Answer

A)  natural evolution of the virus to a less virulent form 
B)  ecological changes affecting the natural reservoir of the virus 
C)  routine vaccination 
D)  changes in global migration patterns 
E)  development of effective anti- viral medications 
A)  natural evolution of the virus to a less virulent form 
B)  ecological changes affecting the natural reservoir of the virus 
C)  routine vaccination 
D)  changes in global migration patterns 
E)  development of effective anti- viral medications

Question 11

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

Accepted Answer

A)  cornea. 
B)  retina. 
C)  conjunctiva. 
D)  iris. 
E)  sclera. 
A)  cornea. 
B)  retina. 
C)  conjunctiva. 
D)  iris. 
E)  sclera.

Question 12

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

A)  patient room cleaning supplies 
B)  skin microbiota of staff 
C)  hospital floral shop 
D)  hospital cafeteria 
E)  therapy pool in the physical therapy department 
A)  patient room cleaning supplies 
B)  skin microbiota of staff 
C)  hospital floral shop 
D)  hospital cafeteria 
E)  therapy pool in the physical therapy department

Question 13

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

A) True 
 B)False

Question 14

What role do capsules and protein A play as virulence factors of Staphylococcus aureus?

Accepted Answer

A)  protect the bacterium from neutrophils 
B)  protect the bacterium from phagocytosis 
C)  form blood clots 
D)  lyse red blood cells 
E)  break down blood clots 
A)  protect the bacterium from neutrophils 
B)  protect the bacterium from phagocytosis 
C)  form blood clots 
D)  lyse red blood cells 
E)  break down blood clots

Question 15

You are a nurse serving as a medical volunteer in a refugee camp. Due to extreme poverty, political instability, and displacement, most individuals at the camp have not received any preventative medical care, including vaccinations. While providing care to a young woman in about the fourth month of pregnancy, she mentions that several children, including her toddler, suffered from a mild illness last month. Her toddler had a low fever, a runny nose, and a rash that started on his face then moved downward. The illness resolved quickly in all the children. What illness might the children have had and why should you be concerned?

Accepted Answer

A)  measles; the children may be more susceptible to other infections 
B)  rubella; the unborn child of the exposed mother may be stillborn or suffer from birth defects 
C)  hand, foot, and mouth disease; the virus may re- activate at a later time 
D)  rubella; it is a mild, self- limiting disease so there are no further concerns 
E)  measles; the child may develop shingles at a later time 
A)  measles; the children may be more susceptible to other infections 
B)  rubella; the unborn child of the exposed mother may be stillborn or suffer from birth defects 
C)  hand, foot, and mouth disease; the virus may re- activate at a later time 
D)  rubella; it is a mild, self- limiting disease so there are no further concerns 
E)  measles; the child may develop shingles at a later time

Question 16

Which statement is not true about leishmaniasis?

Accepted Answer

A)  It is transmitted by sand flies. 
B)  It is a slow infection that can persist for months to years. 
C)  Over twenty different Leishmania species may cause leishmaniasis. 
D)  It is preventable by a vaccine which is recommended for travelers to endemic areas. 
E)  It is most prevalent in the tropics and subtropics. 
A)  It is transmitted by sand flies. 
B)  It is a slow infection that can persist for months to years. 
C)  Over twenty different Leishmania species may cause leishmaniasis. 
D)  It is preventable by a vaccine which is recommended for travelers to endemic areas. 
E)  It is most prevalent in the tropics and subtropics.

Question 17

Which is not a specific cause of reactivation of HSV- 1?

Accepted Answer

A)  hormonal changes 
B)  menstruation 
C)  ultraviolet radiation 
D)  having a cold or fever 
E)  stress 
A)  hormonal changes 
B)  menstruation 
C)  ultraviolet radiation 
D)  having a cold or fever 
E)  stress

Question 18

Why is perspiration an effective defense against microorganisms?

Accepted Answer

A)  basic pH and low salt content 
B)  low salt content 
C)  basic pH, low salt content, and presence of lysozyme 
D)  presence of lysozyme 
E)  basic pH 
A)  basic pH and low salt content 
B)  low salt content 
C)  basic pH, low salt content, and presence of lysozyme 
D)  presence of lysozyme 
E)  basic pH

Question 19

The eyes lack a protective normal microbiota.

Accepted Answer

A) True 
 B)False

Question 20

Because pseudomonads are widespread in the environment and are versatile in their metabolic capabilities, skin infections with these bacteria are common even in healthy people with no skin breaches.

Accepted Answer

A) True 
 B)False

Which factor may influence the specific types of microbes found on the skin?

Describe and contrast three types of bacterial skin infections that can lead to tissue necrosis and death. Name and characterize the causative bacteria, and describe epidemiological and clinical features of each disease.

Most fungal skin infections are likely to remain superficial except in individuals who are immunocompromised.

Cutaneous mycoses usually

Which statement describes an important similarity between chickenpox and smallpox?

Which factor is not a reason Propionibacterium acnes (P. acnes) is often associated with acne?

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?

Which does not apply to ringworm infections?

In streptococcal toxic shock syndrome, pathology results from toxins in the bloodstream which may cause both a red skin rash, as well as

Which factor, beginning in 1995, is responsible for the decline in chicken pox from a routine childhood disease to a rare infection?

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

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?

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.

What role do capsules and protein A play as virulence factors of Staphylococcus aureus?

Which statement is not true about leishmaniasis?

Which is not a specific cause of reactivation of HSV- 1?

Why is perspiration an effective defense against microorganisms?

The eyes lack a protective normal microbiota.

Because pseudomonads are widespread in the environment and are versatile in their metabolic capabilities, skin infections with these bacteria are common even in healthy people with no skin breaches.

Introduction to Microbiology

Biochemistry Basics

Introduction to Prokaryotic Cells

Introduction to Eukaryotic Cells

Genetics

Viruses and Prions

Fundamentals of Microbial Growth

Microbial Metabolism

Principles of Infectious Disease and Epidemiology

Host-Microbe Interactions and Pathogenesis

Innate Immunity

Adaptive Immunity

Immune System Disorders

Vaccines and Biotechnology-Based Diagnostics and Therapeutics

Antimicrobial Drugs

Respiratory System Infections

Nervous System Infections

Digestive System Infections

Urinary and Reproductive System Infections

Cardiovascular and Lymphatic Infections

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Exam 17: Skin and Eye Infections

Which factor may influence the specific types of microbes found on the skin?

Describe and contrast three types of bacterial skin infections that can lead to tissue necrosis and death. Name and characterize the causative bacteria, and describe epidemiological and clinical features of each disease.

Most fungal skin infections are likely to remain superficial except in individuals who are immunocompromised.

Cutaneous mycoses usually

Which statement describes an important similarity between chickenpox and smallpox?

Which factor is not a reason Propionibacterium acnes (P. acnes) is often associated with acne?

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?

Which does not apply to ringworm infections?

In streptococcal toxic shock syndrome, pathology results from toxins in the bloodstream which may cause both a red skin rash, as well as

Which factor, beginning in 1995, is responsible for the decline in chicken pox from a routine childhood disease to a rare infection?

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

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?

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.

What role do capsules and protein A play as virulence factors of Staphylococcus aureus?

Which statement is not true about leishmaniasis?

Which is not a specific cause of reactivation of HSV- 1?

Why is perspiration an effective defense against microorganisms?

The eyes lack a protective normal microbiota.

Because pseudomonads are widespread in the environment and are versatile in their metabolic capabilities, skin infections with these bacteria are common even in healthy people with no skin breaches.

Introduction to Microbiology

Biochemistry Basics

Introduction to Prokaryotic Cells

Introduction to Eukaryotic Cells

Genetics

Viruses and Prions

Fundamentals of Microbial Growth

Microbial Metabolism

Principles of Infectious Disease and Epidemiology

Host-Microbe Interactions and Pathogenesis

Innate Immunity

Adaptive Immunity

Immune System Disorders

Vaccines and Biotechnology-Based Diagnostics and Therapeutics

Antimicrobial Drugs

Respiratory System Infections

Nervous System Infections

Digestive System Infections

Urinary and Reproductive System Infections

Cardiovascular and Lymphatic Infections

Filters