Question 1

Acute sinusitis usually occurs as a complication of

Accepted Answer

Acute sinusitis is most commonly caused by a viral infection that leads to inflammation of the sinus membranes. This inflammation can then lead to bacterial overgrowth and secondary bacterial infection, but the initial trigger is usually a viral infection such as the common cold.

Question 2

What is the cause of reduced clearance of respiratory secretions that predisposes people to respiratory infections?

Accepted Answer

Reduced clearance of respiratory secretions is caused by obstruction by a foreign body, alterations in the viscosity of the mucus, and immature anatomic development. All of these factors can predispose people to respiratory infections.

Question 3

When reading culture plates from respiratory specimens, what must the microbiologist take into consideration?

Accepted Answer

The microbiologist must take into consideration the types of organisms normally found at the culture site, as this can help to determine if the organisms isolated are likely pathogens or contaminants. The amount of media inoculated and quality control of the media are also important factors to consider but are not as directly related to interpreting the results from the respiratory specimen culture. The patient's physician may provide clinical information, but this is not specifically related to the culture plate results.

Question 4

What does the presence of $\alpha$-hemolytic colonies on a throat culture indicate?

Accepted Answer

F1F1F1S1F1F1F10-hemolytic colonies are Streptococcus pyogenes, which can be a normal microbiota found in the pharynx. However, if other symptoms are present, such as sore throat and fever, it could indicate strep throat and require treatment.

Question 5

What common condition will predispose individuals to acute sinusitis?

Accepted Answer

Allergies can cause inflammation and congestion in the nasal passages, which can lead to acute sinusitis. Cold sores, ear infections, and nosebleeds would not typically be related to the development of acute sinusitis.

Question 6

All the following are virulence factors that allow microorganisms to produce disease, except

Accepted Answer

Mucus production is not a virulence factor that allows microorganisms to produce disease. Adherence, toxin production, and host evasion are all examples of virulence factors that contribute to the ability of a microorganism to cause disease.

Question 7

Why do most physicians treat otitis media empirically?

Accepted Answer

The answer of Why do most physicians treat otitis media...

Question 8

What is helpful when initiating empiric antimicrobial therapy?

Accepted Answer

Knowing the pathogens most likely to cause a particular type of infection is essential when initiating empiric antimicrobial therapy. This knowledge helps select the appropriate antimicrobial agent that is most effective against the suspected pathogens.

Question 9

What is the most common cause of community-acquired pneumonia in adults?

Accepted Answer

Streptococcus pneumoniae is the most common cause of community-acquired pneumonia in adults. Influenza virus may also cause pneumonia, but it is usually a complication of the flu rather than the primary cause. Staphylococcus aureus and Legionella pneumophila are less common causes of pneumonia.

Question 10

Why is pharyngitis produced by group A Streptococcus treated with antimicrobial agents?

Accepted Answer

Group A Streptococcus can cause complications such as rheumatic fever and acute glomerulonephritis, which can result in long-term damage to the heart and kidneys. Treatment with antimicrobial agents helps to prevent these complications.

Question 11

What bacterium may cause up to 50% of all cases of pneumonia in the summer months?

Accepted Answer

Mycoplasma pneumoniae is a common cause of community-acquired pneumonia, especially in the summer and early fall months. It is often called "walking pneumonia" because the symptoms are usually mild and people can continue to do their daily activities despite being infected. Studies suggest that up to 50% of all cases of pneumonia during the summer months may be caused by this bacterium.

Question 12

A patient's normal pharyngeal biota can be altered by all of the following, except

Accepted Answer

Visiting a nursing home can expose a patient to new pathogens that may alter their pharyngeal biota, but chronic illness and recent hospitalization can also disrupt the normal flora. The use of broad-spectrum antimicrobials is well-known to alter the normal flora of any site.

Question 13

What are the two most frequently identified bacterial causes of community-acquired sinusitis?

Accepted Answer

Streptococcus pneumoniae and Haemophilus influenzae are the two most frequently identified bacterial causes of community-acquired sinusitis.

Question 14

What is the most common localized infection of the upper respiratory tract in preschool-age patients?

Accepted Answer

Otitis media is the most common localized infection of the upper respiratory tract in preschool-age patients. Orbital cellulitis, acute sinusitis, and mastoiditis are less common in this age group.

Question 15

What should a microbiologist do if he or she finds $\alpha$-hemolytic colonies on a properly collected sputum specimen on a patient suspected of having lobar pneumonia?

Accepted Answer

F1F1F1S1F1F1F10-hemolytic colonies are not normal microbiota, and it is not known if they are a pathogen for pneumonia. Therefore, a full workup to identify the organism should be performed.

Question 16

Elements of the respiratory tract that can help prevent infection include

Accepted Answer

Nasal hair can help trap and filter out large particles, such as dust and bacteria. The normal microbiota of the respiratory tract can outcompete potentially harmful organisms and prevent their growth. Coughing helps expel mucus and other substances, along with any trapped pathogens, from the respiratory tract. Therefore, all of these factors help prevent infection in the respiratory tract.

Question 17

All of the following are complications of acute sinusitis, except

Accepted Answer

Acute pharyngitis is not a complication of acute sinusitis. The other options listed, meningitis, osteomyelitis, and orbital cellulitis, are potential complications of acute sinusitis.

Question 18

What organisms are most frequently isolated from cultures of individuals with otitis media?

Accepted Answer

Streptococcus pneumoniae and Haemophilus influenzae are the most frequently isolated organisms from cultures of individuals with otitis media.

Question 19

All of the following factors can help the microbiologist differentiate between colonization and infection, except

Accepted Answer

The presence of a pure culture or mixed biota on culture plates does not necessarily help differentiate between colonization and infection, as both can present with either a pure culture or mixed biota. Factors like the method and site of collection, presence of white blood cells, and a compatible clinical syndrome are more indicative of an infection versus colonization.

Question 20

What organism is the predominate cause of epiglottis?

Accepted Answer

Haemophilus influenzae is the predominant cause of epiglottis, also known as acute laryngitis or supraglottitis. Streptococcus pneumoniae, Moraxella catarrhalis, and Bordetella pertussis can cause respiratory infections, but they are not typically associated with epiglottis.

Quiz 32: Upper and Lower Respiratory Tract Infections

Acute sinusitis usually occurs as a complication of

What is the cause of reduced clearance of respiratory secretions that predisposes people to respiratory infections?

When reading culture plates from respiratory specimens, what must the microbiologist take into consideration?

What does the presence of $\alpha$ -hemolytic colonies on a throat culture indicate?

What common condition will predispose individuals to acute sinusitis?

All the following are virulence factors that allow microorganisms to produce disease, except

Why do most physicians treat otitis media empirically?

What is helpful when initiating empiric antimicrobial therapy?

What is the most common cause of community-acquired pneumonia in adults?

Why is pharyngitis produced by group A Streptococcus treated with antimicrobial agents?

What bacterium may cause up to 50% of all cases of pneumonia in the summer months?

A patient's normal pharyngeal biota can be altered by all of the following, except

What are the two most frequently identified bacterial causes of community-acquired sinusitis?

What is the most common localized infection of the upper respiratory tract in preschool-age patients?

What should a microbiologist do if he or she finds $\alpha$ -hemolytic colonies on a properly collected sputum specimen on a patient suspected of having lobar pneumonia?

Elements of the respiratory tract that can help prevent infection include

All of the following are complications of acute sinusitis, except

What organisms are most frequently isolated from cultures of individuals with otitis media?

All of the following factors can help the microbiologist differentiate between colonization and infection, except

What organism is the predominate cause of epiglottis?

Quiz 32: Upper and Lower Respiratory Tract Infections

Acute sinusitis usually occurs as a complication of

What is the cause of reduced clearance of respiratory secretions that predisposes people to respiratory infections?

When reading culture plates from respiratory specimens, what must the microbiologist take into consideration?

What does the presence of α\alphaα -hemolytic colonies on a throat culture indicate?

What common condition will predispose individuals to acute sinusitis?

All the following are virulence factors that allow microorganisms to produce disease, except

Why do most physicians treat otitis media empirically?

What is helpful when initiating empiric antimicrobial therapy?

What is the most common cause of community-acquired pneumonia in adults?

Why is pharyngitis produced by group A Streptococcus treated with antimicrobial agents?

What bacterium may cause up to 50% of all cases of pneumonia in the summer months?

A patient's normal pharyngeal biota can be altered by all of the following, except

What are the two most frequently identified bacterial causes of community-acquired sinusitis?

What is the most common localized infection of the upper respiratory tract in preschool-age patients?

What should a microbiologist do if he or she finds α\alphaα -hemolytic colonies on a properly collected sputum specimen on a patient suspected of having lobar pneumonia?

Elements of the respiratory tract that can help prevent infection include

All of the following are complications of acute sinusitis, except

What organisms are most frequently isolated from cultures of individuals with otitis media?

All of the following factors can help the microbiologist differentiate between colonization and infection, except

What organism is the predominate cause of epiglottis?

What does the presence of $\alpha$ -hemolytic colonies on a throat culture indicate?

What should a microbiologist do if he or she finds $\alpha$ -hemolytic colonies on a properly collected sputum specimen on a patient suspected of having lobar pneumonia?