Respiratory System Infection Case Studies and Homework

The upper respiratory tract is lined with mucous membranes which secrete mucous. What is the purpose of mucous? (a) cools and dries, and traps microbes from the air we breathe (b) warms and humidifies the air we breathe (c) cools and dries the air we breathe (d) warms and humidifies, and traps microbes and debris from the air we breathe (e) traps microbes and debris from the air we breathe

D -- warms and humidifies, and traps microbes and debris from the air we breathe

Which statement does not apply to pneumocystis pneumonia and its causative organism, Pneumocystis jirovecii? (a) HIV-AIDS patient are high-risk for this infection. (b) The fungus does not make spores. (c) The organism has some characteristics found in protozoans rather than fungi. (d) Serological evidence suggests that most people are exposed to the organism in early childhood. (e) Like all other pathogenic fungi, the reservoir is soil.

E -- Like all other pathogenic fungi, the reservoir is soil.

Which statement is not true about the resident microbiota of the respiratory tract? (a) The resident microbiota of a healthy person is limited to just a few species of bacteria. (b) Smoking affects the numbers and types of species in the microbiota. (c) Resident microbiota secrete antimicrobial peptides and compete with pathogens. (d) The lungs have recently been found to contain a resident microbiome that resembles that found in the mouth. (e) Microbiota are only found in the upper respiratory tract.

E -- Microbiota are only found in the upper respiratory tract.

A wildlife biologist might be more likely than the average person to contract which types of atypical pneumonia? (a) tularemia, chlamydophila pneumonia, and psittacosis (b) Legionnaire's disease and psittacosis (c) Legionnaire's disease and Q fever (d) walking pneumonia, chlamydophila pneumonia, and Legionnaire's disease (e) Q fever, psittacosis, and tularemia

E -- Q fever, psittacosis, and tularemia

A 68-year old patient with Alzheimer disease was brought to the emergency room by the staff of a local nursing home. He presented as lethargic with a sallow complexion. He had an admission temperature of 102.4F and a respiratory rate of 33/minute. During respiration, the right side of his chest moved better than the left. He showed dense consolidation of the lower lobe of the left lung on physical exam. A sputum sample revealed blood and a greenish color. A chest x-ray showed tight consolidation of the left lung with evidence of formation of cavities in the lung tissue from cytotoxic damage. The patient complained of chills in the exam room, combined with his fever. A smear of his sputum demonstrated no acid-fast bacteria. 1. What is your presumptive diagnosis for this case? 2. What evidence could the sputum give for this case? 3. Is the reduced respiration rate and unequal chest movement indicative of the pathology? 4. Is this a bacterial or viral disease?

1. The presumptive diagnosis for this case is bacterial pneumonia. 2. The sputum having blood and a greenish color indicate that bacteria. Gram-negative rods. 3. Yes, the lung damage and consolidation would lead to observable changes on a chest X-ray. 4. Bacterial, which warrants antibiotic use.

The development of a pseudomembrane on the tonsils and throat is characteristic of (a) pneumococcal pneumonia. (b) tuberculosis. (c) diphtheria. (d) pertussis. (e) streptococcal pharyngitis.

C -- diphtheria.

You are a physician's assistant at a local pediatrician's office. Five-year-old Michael is brought to the office by his father. Michael is crying and complaining that his mouth hurts. His father has been at work and does not know whether the boy has had a fever during the day. Currently his temperature is 103°F. The physician notices that Michael's breath smells rotten. Lymph nodes in his neck are swollen and visual examination of the throat reveals a white packet adhering to the left tonsil. Much of the soft palate is red. 1. What laboratory tests are called for? 2. What types of infections are in the differential diagnosis (a list of diseases or conditions presenting similar symptoms)? 3. Your practice has recently been overrun by sore throats and now, late in the evening, there are no supplies for performing the proper test. Should the physician prescribe antibiotics or not? 4. In deciding whether to prescribe antibiotics, should the physician be extra careful not to prescribe an unnecessary antibiotic, or be careful not to let a bacterial infection go untreated? 5. What are the possible sequelae (pathological conditions resulting from a disease) of untreated sore throats?

1. Throat culture and rapid antigen test. 2. Pediatric pharyngitis. 3. If there have been other cases, it is likely to be a case of step. The physician should prescribe antibiotics. 4. Careful to not a bacterial infection to go untreated due the possible of the infection developing into scarlet fever or rheumatic fever. 5. Scarlet fever or rheumatic fever

Your 3-year-old patient presents to you with high fever, shaking chills, cough, chest pain, and shortness of breath. The patient's mother stated that symptoms began suddenly last night. The patient is up to date on all vaccinations. Based on this information, which of the following diseases did your patient most likely contract? (a) Pneumococcal pneumonia (b) Pontiac fever (c) Haemophilus pneumonia (d) Walking pneumonia

A -- Pneumococcal pneumonia

Which of the following diseases is caused by Streptococcus pyogenes? To be marked correct, you'll need to select all applicable statements, as there may be more than one correct answer. (a) Streptococcal pharyngitis (b) Diphtheria (c) Impetigo (d) Scarlet fever

A -- Streptococcal pharyngitis C -- Impetigo D -- Scarlet fever

Infection in the respiratory tract is limited by all except (a) the epiglottis sealing the airway during swallowing. (b) ciliated mucous membranes. (c) alveolar macrophage. (d) resident microbiota. (e) coughing to bring microbes away from the lungs.

A -- the epiglottis sealing the airway during swallowing.

A key factor in the high prevalence of otitis media in children is (a) the orientation of the eustachian tube in children prevents efficient fluid drainage. (b) the lack of a mature microbiome in the auditory canal. (c) children are more likely to suffer from colds and influenza than adults. (d) the maturing of the innate and adaptive immune responses in children. (e) children do not complete their routine vaccine schedule until adolescence.

A -- the orientation of the eustachian tube in children prevents efficient fluid drainage.

Influenza A strains are characterized by (a) whether the virus contains DNA or RNA. (b) the country in which the strain originated. (c) whether or not humans are infected. (d) the type of HA and NA spikes found on the viral surface. (e) the type of animal in which the strain originated.

D -- the type of HA and NA spikes found on the viral surface.

SARS is caused by a(n) (a) influenza virus. (b) adenovirus. (c) rhinovirus. (d) paramyxovirus. (e) coronavirus.

E -- coronavirus

A 21-year-old male is admitted to the hospital in severe respiratory distress. Despite care, he died of rapid pulmonary edema within 12 hours of admission. Family members report that he had recently started work at a nearby state park. He was on a detail to clean out and renovate a group of rodent-infested rental cabins. Based on the information, what is the likely diagnosis? (a) respiratory syncytial virus (b) SARS (c) human parainfluenza virus infection (d) influenza H1N1 (e) hanta pulmonary syndrome

E -- hanta pulmonary syndrome

An unusual feature of the 1918 Spanish influenza pandemic is that (a) it originated in Europe, rather than Asia as most influenza strains do. (b) most fatalities were among young adults, and victims had unusually poor immune responses to the virus. (c) it originated in Europe, most fatalities were among young adults, and victims had unusually poor immune responses. (d) victims had unusually poor immune responses to the virus. (e) most fatalities were among young adults, rather than infants or the elderly.

E -- most fatalities were among young adults, rather than infants or the elderly.

As an epidemiologist working for the World Health Organization for the past five years, Kelsey has lived in many parts of the world. For the past two years she served in the Emerging Disease Surveillance and Response Team stationed in Manila, Philippines. About two months ago she traveled to the United States for a meeting. Over the past month, she has felt fatigued. She developed a cough that occasionally generates yellow-tinged sputum. She hadn't weighed herself in several weeks, but felt like her clothes were fitting more loosely. She was somewhat surprised, since she hadn't been trying to lose weight, but she had almost no appetite lately. She has not experienced a fever or chills. Kelsey went to a clinic in Manila, where she was prescribed a broad-spectrum antibiotic (clarithromycin) to treat what the doctor felt was probably a case of bronchitis. After finishing the course of antibiotics, Kelsey still felt fatigued and her cough persisted. Within two days of finishing her course of clarithromycin she developed a fever, chills, night sweats; she occasionally coughed up sputum that was tinged with blood (hemoptysis). After two days of these worsening symptoms, she returned to the clinic where she meets you—the physician assistant on duty at the time. After your routine exam, you discover that Kelsey has lost 10 pounds in the past 4-6 weeks. Questioning her further, you learn she is married and has been in good health until recently, is not diabetic, and is HIV negative. Kelsey is a nonsmoker who is up to date on her standard vaccines and booster shots. Her vaccine records show she had the bacillus Calmette-Guérin vaccine as an infant. She did have a positive tuberculin skin test last year, but no signs of latent or active TB were found afterward. You decide to order a chest X-ray, take a sample of her sputum for culture and microscopy analysis, and order an interferon gamma release assay. You did not order a tuberculin skin test. While you wait for the test results, you admit Kelsey to the clinic and assign her to an isolation room. 1. As the physician assistant on duty you have developed a working diagnosis to help you care for Kelsey. What disease do you suspect? (a) Active case of tuberculosis (b) Respiratory syncytial virus (c) Legionnaire's disease (d) Aspergillosis 2. If the microscopy and culture of Kelsey's sputum sample confirm acid fast bacilli, what results do you expect to see from her chest X-ray and interferon gamma release assay? (a) The chest X-ray should be normal and the interferon gamma release assay should be positive. (b) The chest X-ray should be abnormal and the interferon gamma release assay should be positive. (c) The chest X-ray should be abnormal and the interferon gamma release assay should be negative. (d) The chest X-ray should be normal and the interferon gamma release assay should be negative. 3. If the microscopy and culture of Kelsey's sputum sample do not confirm acid-fast bacilli, what would the X-ray and interferon gamma release assays show? (a) The chest X-ray should be normal and the interferon gamma release assay should be positive. (b) The chest X-ray may still be abnormal and the interferon gamma release assay should be positive. (c) The chest X-ray may still be abnormal and the interferon gamma release assay should be negative. 4. Explain why you did not order a tuberculin skin test. (a) Patients who received the bacillus Calmette-Guérin vaccine will have a positive tuberculin skin test result regardless of tuberculosis infection status. (b) The patient does not show signs and symptoms of an active or latent tuberculosis infection. (c) The patient is showing signs of a latent tuberculosis infection, and the tuberculin skin test is only positive for active cases of tuberculosis. (d) The tuberculin skin test is expensive and difficult to interpret. 5. Why is the patient's HIV status important in this case? Select all that apply. (a) Individuals with HIV are more likely to contract and display active forms of tuberculosis infection. (b) Tuberculosis is a leading cause of death for HIV/AIDS patients. Thus the prognosis and care plan may change accordingly. (c) Certain test results (such as the tuberculin skin test) may appear different in HIV/AIDS patients than in non-HIV/AIDS patients. (d) Individuals with HIV are unable to receive combination drug therapy, leading to MDR and XDR TB infections. 6. Explain why you put Kelsey in isolation. (a) Patients with anorexia must be placed into isolation. (b) Kelsey received the live, attenuated bacillus Calmette-Guérin vaccine and will thus be able to spread the tuberculosis pathogen to other patients. (c) Patients must be placed in isolation when manifesting a fever. (d) Kelsey may have an active case of tuberculosis and is at risk for exposing other patients to the illness. 7. Why did the physician who first saw Kelsey assume she had bronchitis? Select all that apply. (a) Outbreaks of bronchitis are mostly localized to southeastern Asia where Kelsey works. (b) Earlier in her infection, Kelsey was not displaying all of the classic signs of tuberculosis. Instead, she was displaying symptoms of bronchitis. (c) Bronchitis is a very common infection, especially compared to tuberculosis. (d) Kelsey did not receive a vaccine protecting her against bronchitis. 8. If the chest X-ray comes back abnormal, but bacteria are not observed in or cultured from the sputum, and the interferon gamma release assay is negative, what are some possible differential diagnoses based on the patient's symptoms? (a) Scarlet fever (b) Pneumococcal pneumonia (c) Diptheria (d) Otitis media

1. A -- Active case of tuberculosis 2. B -- The chest X-ray should be abnormal and the interferon gamma release assay should be positive. 3. C -- The chest X-ray may still be abnormal and the interferon gamma release assay should be negative. 4. A -- Patients who received the bacillus Calmette-Guérin vaccine will have a positive tuberculin skin test result regardless of tuberculosis infection status. 5. A -- Individuals with HIV are more likely to contract and display active forms of tuberculosis infection. B -- Tuberculosis is a leading cause of death for HIV/AIDS patients. Thus the prognosis and care plan may change accordingly. C -- Certain test results (such as the tuberculin skin test) may appear different in HIV/AIDS patients than in non-HIV/AIDS patients. 6. D -- Kelsey may have an active case of tuberculosis and is at risk for exposing other patients to the illness. 7. B -- Earlier in her infection, Kelsey was not displaying all of the classic signs of tuberculosis. Instead, she was displaying symptoms of bronchitis. C -- Bronchitis is a very common infection, especially compared to tuberculosis. 8. Possible differential diagnosis: B -- pneumococcal pneumonia Not possible differential diagnosis: A -- Scarlet fever, C -- diphtheria, D -- otitis media

A 26-year-old man reports to his physician in late October, complaining of a sudden onset of fever, a dry cough, headache, and body aches. The man states that he received his flu shot 10 days prior and must have gotten the flu from the immunization. He also states that he had just returned two days before from a weeklong trip to Hong Kong. He mentions that a highlight of his trip was a visit to the farmers' market filled with fresh produce and livestock. A culture confirms that the patient is infected with influenzavirus. 1. Could this patient have gotten the flu from the "shot"? (a) Yes. The injectable multivalent influenza vaccine contains three different strains of inactivated viruses. (b) No. The injectable multivalent influenza vaccine contains inactivated virus. It cannot cause the disease. (c) No. The injectable multivalent influenza vaccine contains three different strains of attenuated virus. (d) Yes. The injectable multivalent influenza vaccine contains three different strains of attenuated viruses. 2. Why should children and teenagers never be given aspirin to treat the fever and aches of influenza? (a) Infection with influenza and treatment with aspirin are associated with the development of Reye's syndrome. (b) Infection with influenza and treatment with aspirin are associated with the development of Creutzfeldt-Jakob disease. (c) Infection with influenza and treatment with aspirin may result in hives and itchy skin. (d) Infection with influenza and treatment with aspirin are associated with the development of Guillain-Barré syndrome. 3. The culture indicates that this is a drastically different flu strain from those seen in recent years. How do you explain this? (a) Antigenic shift has produced major antigenic changes in the viral genome. (b) Antigenic drift has produced major antigenic changes in the viral genome. (c) The virus has lost its envelope. (d) The viral genome shifts from eight segments of RNA to eight segments of DNA. 4. What is the function of neuraminidase spikes? (a) Neuraminidase releases the influenza virions from the host cell. (b) Neuraminidase cuts the viral genome into eight segments. (c) Neuraminidase spikes function as ligands that bind to host receptors. (d) Neuraminidase spikes glue the envelope to the viral capsid. 5. What is the mode of action for zanamivir? (a) Zanamivir is a nucleoside analog. (b) Zanamivir is a neuraminidase inhibitor. (c) Zanamivir is an RNA polymerase inhibitor. (d) Zanamivir is a protease inhibitor.

1. B -- No. The injectable multivalent influenza vaccine contains inactivated virus. It cannot cause the disease. 2. A -- Infection with influenza and treatment with aspirin are associated with the development of Reye's syndrome. 3. A -- Antigenic shift has produced major antigenic changes in the viral genome. 4. A -- Neuraminidase releases the influenza virions from the host cell. 5. B -- Zanamivir is a neuraminidase inhibitor.

Twenty-one-year-old Marjorie comes to the family practice office for evaluation of a dry cough that has not gotten better over the last seven days. Before she started coughing, she had a mild fever, runny nose, and sneezing for 10 days, but she was able to carry out her usual routine. She reports "coughing spells" frequently during the day and recalls one episode in which she gagged and vomited. She has a mild coughing episode while in the office, and although it is paroxysmal, there is no "whoop" noted. Marjorie is a part-time college student attending evening classes and helps her aunt with her younger cousins during the day. Her cousins are five years old and six weeks old and also come to the same office for health care. Both cousins appear well, without any signs or symptoms, and a review of their charts reveals they are current for all scheduled vaccines. Marjorie's last vaccine was at age 16. 1. Should a lower respiratory infection such as pertussis be considered the cause of the symptoms instead of rhinitis or sinusitis for this patient? Why? (a) No, this patient would have had the DTP vaccine as a child. (b) No, she is not presenting with the characteristic deep "whoop" cough. (c) Yes, pertussis may occur in older individuals. (d) No, pertussis is a disease of young children. 2. Which of the stages listed is NOT considered one of the clinical stages associated with pertussis? (a) paroxysmal (b) latency (c) convalescence (d) catarrhal 3. To diagnostically confirm the presence of Bordetella pertussis and the diagnosis of whooping cough, which medium should be used to cultivate respiratory samples in the morning at the bedside of the patient? (a) chocolate agar (b) eosin methylene blue agar (c) sheep's blood agar (d) Bordet-Gengou agar 4. Should any of Marjorie's family members whom she comes into contact with be considered at risk of pertussis? If so, who? (a) Yes, the aunt should be considered at risk. (b) Yes, the six-week-old cousin should be considered at risk. (c) Yes, the five-year-old cousin should be considered at risk. (d) No, no one should be considered at risk. 5. How is B. pertussis and whooping cough transmitted from one person to the next? (a) insertion into wound (b) ingestion of respiratory secretions (c) inhalation of respiratory droplets (d) inhalation of bacterial endospores

1. C -- Yes, pertussis may occur in older individuals. 2. B -- latency 3. D -- Bordet-Gengou agar 4. B -- Yes, the six-week-old cousin should be considered at risk. 5. C -- inhalation of respiratory droplets

A woman reports to the emergency room in January with her cyanotic (blue-colored) 10-month-old child. The mother reports that the infant has had a runny nose, fever, and slight cough for a day and has had increasing trouble breathing. The child does not have a history of bronchial disease and was not premature. The mother also states that the infant's five-year-old brother is recovering from symptoms that resemble a cold. 1. Based on the age and symptoms, what presumptive diagnosis would you consider? (a) diphtheria infection interfering with breathing (b) pneumonia due to Haemophilus influenza infection (c) pertussis infection inducing apnea (d) bronchitis due to RSV infection 2. What treatment would be best to begin based on your presumptive diagnosis? (a) supportive therapy at home to maintain hydration levels and allow infection to run its course (b) high dosage of oral erythromycin to clear bacterial infection (c) supportive therapies in the hospital to maintain blood oxygen levels and open airways (d) low dosage of erythromycin given intravenously to clear the bacterial infection 3. What prophylactic treatment should the infant have received to diminish the chances of this infection? (a) influenza shot (b) toxin antiserum (c) DTaP vaccine (d) MMR vaccine 4. While the presence of Bordetella pertussis colonizing the airways of an infant or child will induce inflammation and interfere with breathing, the tracheal toxin is what may lead to the greatest interference. What is the mode of action associated with this toxin? (a) The toxin interferes with the phagocytic mechanisms of resident macrophages in the lungs. (b) The toxin induces hemorrhage of blood vessels, resulting in cell death. (c) The toxin increases mucus production in the lungs to overcome the ciliary escalator action. (d) The toxin interferes with the action of cell surface cilia lining the bronchi, stopping the ciliary escalator. 5. Could the infant's pertussis infection be linked to the older sibling's sickness? (a) The infant may have developed the infection from the vaccinations. (b) The five-year-old may have had pertussis without the characteristic whooping cough and passed the infection to the infant. (c) If the five-year-old had had pertussis, then he would have had the characteristic whooping cough and so he did pass the infection to the infant. (d) A five-year-old is too old for a pertussis infection, so he could not be the source of the infection to the infant.

1. C -- pertussis infection inducing apnea 2. C -- supportive therapies in the hospital to maintain blood oxygen levels and open airways 3. C -- DTaP vaccine 4. D -- The toxin interferes with the action of cell surface cilia lining the bronchi, stopping the ciliary escalator. 5. B -- The five-year-old may have had pertussis without the characteristic whooping cough and passed the infection to the infant.

It is mid-July. You are working as a triage nurse in the emergency department of a small suburban hospital in Arizona. A young, athletic-looking man in his early 20s is helped into your office by his girlfriend. He greets you and sits down, but is feverish and his breathing is labored. The girlfriend answers your questions for him. She says the symptoms began about 24 hours ago and seemed to worsen quickly. It looks like the flu to you, but the season is wrong. So you ask about the man's activities over the past week to 10 days. Nothing in this history points to an obvious etiology for the disease. And the girlfriend, rather defensively, adds that she is a "neat-freak" and is constantly cleaning and disinfecting the house they share. But of course, respiratory infections are very common and can be acquired anywhere. After listening to his chest you decide that it may be bronchitis or influenza. You decide to isolate him from the rest of the people in the waiting room until an examining room becomes free. Forty-five minutes later the girlfriend comes barreling into your office. "I think he's choking!" she screams. You and the attending physician arrive at his bed where he indeed seems to be suffocating. His face is red and he is gripping his throat. The doctor calls out, "acute respiratory distress," and a team moves in to try to restore his breathing. Later that evening, on your way out, you learn that the patient has died. Several days later the charge nurse tells you what the patient's lab work revealed. It identified an infection that he probably acquired a few weeks earlier while he and his girlfriend stayed in an isolated cabin his family owned but seldom used. 1. What is the diagnosis? 2. What connection does the diagnosis have with the cabin? 3. You overhear the charge nurse say to herself: "I knew there was a good reason not to clean my house." To what could she have been referring? 4. This case is from Arizona. These infections were first seen in the United States in May of 1993 in the Four Corners area of the Southwest, which includes Arizona, Colorado, New Mexico, and Utah. Can we assume that this disease is only found in the Southwest? What factors determine the places this virus might be present.

1. Hantavirus pulmonary syndrome 2. Since the cabin was seldom inhabited, rodents have likely begun to live there and contaminated the cabin with little ventilation. 3. Since the virus was found in rodent hair and droppings, when cleaning, the virus was aerosoled to be inhaled. 4. No the disease is not only found in the Southwest US. Other cases have been found in elsewhere in the North and South America.

One autumn in the late 1990's, a number of people became ill after working at a single building at an industrial plant in a neighborhood of Baltimore, Maryland. Their symptoms ranged from simple coughing and other respiratory symptoms to pneumonia. At least one of the 70 people reporting symptoms died. The company voluntarily closed the building upon the recommendation of the Maryland Department of Health and Mental Hygiene. After all of the water systems at the plant were evaluated and disinfected, it reopened and no new cases were reported. 1. Health departments often have even less information than this when they have to start hypothesizing about the causative organism and its source. What is your first guess? 2. Describe the transmission characteristics of the suspected bacterium. 3. Is there a risk for a continuing community outbreak from these initial infections? Why or why not? 4. Would the health department be likely to identify this bacterium by performing routine water-screening procedures, such as serial dilution or filter collection followed by inoculating on eosin methylene blue (EMB) or nutrient agar? Explain.

1. Legionnaire's disease. 2. The transmission occurs via aerosols. The virus replicates within phagocytes and releases with apoptosis. It kills the lining of the air sacs. 3. Yes, if it is in the water supply, the water supply is contaminated. That is why it is important to disinfect the water systems at the plant. 4. No, this is a protozoan and an EMB is used for bacteria.

A lethargic 22-month old black female was presented by her mother to the emergency room at 2:15am on a Sunday. The child had a history of a runny nose, hoarse cough and low-grade fever (~99F) for the past 48 hours. The mother was concerned about the forced and noisy breathing of the child. The pediatrician examined the child and found cloudy eyes and mild inflammation of the ears, but no overt signs of bacterial infection (no significant changes in the eardrums). The throat of the child was red and coated with mucus. The larynx was swollen and raw. The physician performed a rapid Strep test and found it was negative. Throat swabs were taken for culture. The physician placed the child in a room with a warm vaporizer for about 30 minutes. This dramatically improved the breathing of the child. 1. What is the presumptive diagnosis for this case? 2. Will the throat cultures likely show evidence of Streptococcus pyogenes? How about Staphylococcus aureus? 3. Do you believe that this is a bacterial or viral disease? Why? 4. What further treatment is indicated for this case?

1. Pertussis is the presumptive diagnosis. 2. The throat culture will not show evidence of Streptococcus pyogenes. It is unlikely that Staphylococcus aureus since it typically infects the skin. 3. Viral because there are no obvious signs that it is bacterial and symptoms improved with the vaporizer. 4. Further supportive care, like continuing to use the vaporizer to relive symptoms and a fever reducer.

For the past couple of days, Shelly has had a scratchy feeling in her throat. When she woke up this morning, she noticed that her throat hurt and that she had trouble swallowing. She also felt a bit feverish, so she decided to go to the doctor. At the doctor's office, Dr. Simpson confirms that Shelly has a fever. He takes two swabs from her throat and also feels her neck lymph nodes, which are swollen. A short time later, Dr. Simpson tells Shelly that one of the swabs was used for a rapid strep test and that the test was positive, indicating that Shelly has strep throat caused by Streptococcus pyogenes. 1. The symptoms that Shelly is experiencing result from the interactions between Streptococus pyogenes (a prokaryote) and the cells (eukaryotes) within Shelly's body. Although there are similarities between these two types of cells, there are also important differences. (a) Nucleus (b) Capsule (c) Cytoplasm (d) Plasma membrane (e) Rough endoplasmic reticulum (f) Golgi complex (g) Flagella (h) Mitochondria (i) Ribosomes 2. Skipped 3. Analysis of the second swab has confirmed that the causative organism is Streptococcus pyogenes, a gram-positive organism. Imagine that you are the technician looking at the Gram stain from Shelly's culture. What would you expect to see as you look through the microscope? (a) pink, rod-shaped organisms arranged in pairs (b) pink, spherical-shaped organisms arranged in chainlike formations (c) purple, spherical-shaped organisms arranged in chainlike formations (d) purple, spherical-shaped organisms arranged in grapelike clusters 4. How will the prescribed penicillin kill S. pyogenes that is causing Shelly's infection? (a) Penicillin will poke holes in the plasma membrane, weakening the cell and leading to cellular lysis. (b) Penicillin will interfere with peptidoglycan synthesis, ultimately weakening the cell wall and leading to cellular lysis. (c) Penicillin will disrupt the outer membrane, leading to a loss of structural integrity and death of S. pyogenes. (d) Penicillin will attach to bacterial ribosomes and inhibit protein synthesis, which will lead to the death of S. pyogenes. 5. What effect will the penicillin have on Shelly's cells? (a) There will be no impact on Shelly's cells because penicillin targets the flagella, which are found only in bacteria. (b) The penicillin will not have any impact on Shelly's cells because it targets peptidoglycan, which is found only in bacteria. (c) The penicillin will kill some of Shelly's cells because it targets the ribosomes, a structure found in both prokaryotes and eukaryotes. (d) The penicillin will also kill some of Shelly's cells by disrupting the structure of the plasma membrane.

1. Prokaryote only: B -- capsule Eukaryote only: A -- nucleus, E -- Rough endoplasmic reticulum, F -- Golgi apparatus, H -- Mitochondria Both: C -- Cytoplasm, D -- Plasma membrane, G -- Flagella, I -- Ribosomes 3. C -- purple, spherical-shaped organisms arranged in chainlike formations 4. B -- Penicillin will interfere with peptidoglycan synthesis, ultimately weakening the cell wall and leading to cellular lysis. 5. B -- The penicillin will not have any impact on Shelly's cells because it targets peptidoglycan, which is found only in bacteria.

You and your friends are driving to the mall; it is late October. A public service announcement comes on the radio urging people to get their flu vaccinations. You are a second-year nursing student and you mention that the nursing staff at your university is holding a vaccine clinic next week. Your friend Susan says, "I'm not getting a flu shot! The last time I did, it gave me the flu." Others in the car agree with her. But Heather asks you if it's true that the vaccine can give you the flu. 1. What would your answer to Heather's question be? 2. Heather says that because she had a flu shot last year she's going to skip it this year. Respond, with an explanation. 3. What is the most likely treatment for this illness? Why is it important? 4. What factors of this case allowed you to make a presumptive diagnosis? 5. Susan wants to know why you don't have to get other vaccines annually. 6. Another friend, Dru, says that even though she had the flu shot last year she got terribly sick with the stomach flu over Thanksgiving break and missed most of her vacation. What is your explanation for this?

1. The flu shot cannot give you the flu because it contains inactivated viral particles. 2. It is important to get the flu shot every year, because the influenza virus is always changing. A new flu vaccine is created every year that is based on what the WHO believes will circulate. 3. Antigenic drift is the surface of the flu virus that is constantly changing the chemical composition slightly. Antigenic shift is an abrupt change in the virus's composition. 4. Flu strains are different every year due to antigenic drift. The WHO makes an educated guess on which strain of the flu will be circulating each year and makes a vaccine accordingly. 5. Not all infectious microbes change the same way influenza does. The changes result from genetic mutations. 6. What people refer to as the stomach flu is not a flu at all since it does not come from the influenza virus. The influenza virus only causes respiratory symptoms.

A 22-year old male college student was presented at the ESU health clinic. He looked tired and pale. He presented because of high fever and chest pain. He was afraid he was having a heart attack (bad week of exams). He was examined immediately by the PA and an EKG strip was run. He had no evidence of acute heart problems. The attending physician visited the patient. He obtained the following history from the past 36 hours. The patient had a tight cough. He had significant muscle aches and pains. He had a bad headache and had had fevers of 101-103F. The physician ordered a chest x-ray. It did not show any significant consolidated inflammation suggestive of pneumonia. The patient showed significant nasal drainage and a moderately tight, but productive cough on physical exam. He had a fever of 101F and generally inflamed mucous membranes. A rapid Strep test showed no evidence of Streptococcal infection and his tonsils and adenoids had been removed. 1. What is the most likely diagnosis for this patient? On what do you base this diagnosis? 2. What secondary infection problems should be monitored? 3. What is the preferred treatment for this disease?

1. The most likely diagnosis is influenza. Symptoms resemble a severe cold. There is no evidence of strep, and no indication of pneumonia. 2. Risk of developing bacterial pneumonia. 3. Supportive care including fluids, bed rest, and fever reducing medication.

At the Mount Union hospital, a 5-year old white male child in good general health and physical condition was presented at the Saturday walk-in clinic by his mother. He was brought in because he had a fever, was cranky and had complained of a sore throat for about 24 hours. On physical examination by the attending resident, the patient had a fever of 39.3C, and he had considerable swelling and drainage of the pharynx and in the conjunctivae. His tonsils were enlarged and coated with a white patchy exudate. He had a red throat and swollen anterior cervical lymph nodes. His ears were clear. His chest sounded clear and he had no additional remarkable findings on routine examination. 1. What would be your presumptive diagnosis for this child? Why? 2. What diagnostic testing would be indicated to follow this exam? 3. What is the most likely treatment for this illness? Why is it important? 4. What factors of this case allowed you to make a presumptive diagnosis?

1. The patient has streptococcal pharyngitis. The patient has classical symptoms of the disease such as inflammation of the throat (presented as a sore throat), swollen anterior cervical lymph nodes, a low-grade fever, and white exudate in the throat. 2. A rapid strep test would be done to indicate S. pyogenes. 3. A penicillin-based drug would be prescribed except in the case that the patient is allergic to penicillin. Treatment would last about 10 days on the antibiotic. This is important to prevent complications and other illnesses such as scarlet fever and rheumatic fever. 4. Lack of cough and clear lungs, exudate on the tonsils and pharynx, low-grade fever, and patient history.

Julie's husband Doug has not been feeling well for the past 10 days. He has congestion in his lungs and has been very tired. She talked him into going to the doctor a week ago when his temperature was 101°F. The doctor gave him some oral amoxicillin, which he took faithfully until it was gone. But she still thinks he looks sick. Julie, Doug, and their 3-year-old daughter have just moved to Ohio from Arizona. Doug is a park ranger and loves his job, but for the past three days he has felt too sick to go to work. His respiratory symptoms have not improved. Julie makes an appointment for him with her doctor. 1. As the physician's assistant in the office, you are the first to examine Doug. What's your tentative diagnosis, based on the history. 2. Which components of the history support your tentative diagnosis? 3. Doug's condition has not responded to the antibiotic. List two possible reasons for this finding. 4. What are some other conditions caused by this microorganism? 5. Should Julie worry that Doug can transmit the infection to her or to their daughter? 6. What precautions can be taken by other workers who may be regularly or heavily exposed to bat or bird droppings?

1. The tentative diagnosis is Histoplasmosis. 2. The recent move from Arizona to Ohio and Doug's work as a park ranger. 3. One possible reason is that the infection is fungal, not bacterial. Another reason is that the strain may be resistant to the antibiotic. 4. Fever, chest pain, and cough. 5. No, unless there is an underlying health condition such as an organ transplant. 6. Personal protective equipment such as a mask.

When you left for school this morning your 3-month-old son was wheezing a bit and he had a slight fever of 99.8°F. Your mother is watching him while you come to school to take your anatomy and physiology exam. Your pager goes off halfway through the exam. The baby's fever is rising and he is having more trouble breathing. Your mother says she is taking him to the emergency room. You rush over to the hospital. When you get there, he is in an examining room and the doctor is signing papers to admit him to intensive care. She says she suspects some kind of pneumonia. She mentions the type of pneumonia but you don't recognize the name and you are too worried about your son to pin her down at this moment. You do note that she mentions that the hospital has seen a dozen pediatric cases of the same type of pneumonia in the past week and a half. The doctor swabs your son's nose but says the results won't be back for several days. In the meantime, they will give him supportive therapy, including an inhaled spray, but no antibacterial drugs. The doctor says that she feels sure that he child will recover since the infection was caught very early. Nonetheless, after she leaves, your mother is frantic and indignant. She fires off the following questions to you. 1. What kind of pneumonia is it? 2. Why aren't they giving him antibacterial drugs? 3. Do you believe that this is a bacterial or viral disease? Why? 4. What further treatment is indicated for this case?

1. Viral pneumonia; respiratory syncytial virus 2. It's a viral infection so antibacterial drugs won't work. 3. Multiple cases of the same thing over the past week and a half. 4. She has already been exposed and most children this age have already been exposed and built up a strong enough immunity to it.

The infectious agent that causes tuberculosis is (a) an acid-fast bacterium of the genus Mycobacterium. (b) HIV. (c) avian influenza virus. (d) unpasteurized milk. (e) one of several Gram-negative bacterial species.

A -- an acid-fast bacterium of the genus Mycobacterium

Influenza differs from the common cold in that (a) it has a greater fatality rate. (b) you can get only get influenza once. (c) it is not treatable with antivirals. (d) it can cause seasonal outbreaks. (e) the virus is not subject to mutation.

A -- it has a greater fatality rate

An adult patient with an influenza infection can be distinguished from an adult patient with a common cold based on the presence of which symptom/sign of infection? (a) Runny nose (b) High, prolonged fever (c) Sore throat (d) Thickened, opaque, and discolored mucus

B -- High, prolonged fever

An endemic fungal infection that is found in the semi-arid to dry soils in the southwestern United States and Mexico is (a) histoplasmosis. (b) coccidioidomycosis. (c) blastomycosis. (d) murcomycosis. (e) aspergillosis.

B -- coccidioidomycosis

A contributing factor to the spread of the SARS virus during the initial 2003 outbreak was (a) high smoking rates in Asia. (b) global air travel. (c) air pollution in crowded urban environments. (d) similarity to 1918 influenza outbreak. (e) transmission of the virus in healthcare settings.

B -- global air travel

Histoplasmosis should be suspected in cases of fungal respiratory infections found in (a) dog owners. (b) the Mississippi and Ohio River valley regions. (c) HIV-AIDS patients. (d) cattle or dairy farm workers. (e) construction workers.

B -- the Mississippi and Ohio River valley regions.

Histoplasmosis (caused by the fungal pathogen Histoplasma capsulatum) is typically seen only in the Ohio and Mississippi river valleys, whereas Aspergillosis (caused by the fungal pathogen Aspergillus fumigatus) is widespread regardless of geographical location. Which of the following statements describes why this disparity with regards to disease distribution occurs? (a) The arthropod vector that carries Histoplasma capsulatum is only found in the Ohio and Mississippi valley regions, whereas the arthropod vector that carries Aspergillus fumigatus is found in many geographical locations. (b) Histoplasma capsulatum is an opportunistic fungal pathogen affecting immunocompromised individuals, whereas Aspergillus fumigatus is a true fungal pathogen affecting both healthy and immunocompromised individuals. (c) Histoplasma capsulatum is an endemic fungus that prefers soils enriched with bat guano, whereas Aspergillus fumigatus is a ubiquitous soil fungus. (d) Individuals are not as routinely vaccinated against Aspergillosis as compared to Histoplasmosis.

C -- Histoplasma capsulatum is an endemic fungus that prefers soils enriched with bat guano, whereas Aspergillus fumigatus is a ubiquitous soil fungus.

Your elderly patient presents with shortness of breath, fever, wheezing upon inhalation, and chest pain. Her case history reveals that her symptoms were preceded by cold-like symptoms and a persistent dry cough. Based on her initial symptoms, penicillin (an antimicrobial drug that hydrolyzes peptidoglycan found in bacterial cell walls) was prescribed and shown to be ineffective. A sputum sample taken from the patient reveals that the pathogen does not have a cell wall. Based on this information, which of the following pathogens is most likely the causative agent of the infection? (a) Chlamydia pneumoniae (b) Legionella pneumophila (c) Mycoplasma pneumoniae (d) Streptococcus pneumoniae

C -- Mycoplasma pneumoniae

A diagnostic sign of typical pneumonia is consolidation which (a) is a granuloma walling off infected phagocytes in the lungs and appears as a clear region on a chest X-ray. (b) is a granuloma walling off infected phagocytes in the lungs. (c) appears as a white or hazy opaque region on a chest X-ray (d) is fluid rather than air in the alveoli and appears as a clear region on a chest X-ray. (e) is fluid rather than air in the alveoli.

C -- appears as a white or hazy opaque region on a chest X-ray

An otherwise healthy 20-year-old college student and an archaeological research team travelled to Northwest Arizona to excavate Navajo ruins. One month after returning, the student develops a flu-like cough with a low-grade fever accompanied by a non-pruritic maculopapular rash on the extremities. The microorganism causing the illness appears as a mold on Sabouraud agar when incubated at room temperature for 10 days. Based on the case information and laboratory results, which of the following diseases is the patient most likely afflicted by? (a)Blastomycosis (b) Histoplasmosis (c)Coccidioidomycosis (d) Mucormycosis

C -- coccidioidomycosis

A two-year-old child presents to a pediatric practice with a barking cough and loud wheezing. The parent is alarmed and insists on antibiotics. What is the likely diagnosis, and are antibiotics appropriate? (a) allergies / no, allergies are caused by irritants and are not infections (b) sinusitis / no, most cases are due to viral infections or irritants (c) croup / no, most cases are viral (d) epiglottitis / yes, this is a life-threatening bacterial infection (e) pneumonia / yes, this can be a life-threatening condition and is often bacterial

C -- croup / no, most cases are viral

Pneumonia is (a) inflammation of the entire lower respiratory tract except the lungs. (b) shortness of breath. (c) inflammation of the alveoli which interferes with gas exchange. (d) wheezing or loud breathing associated with airway obstruction. (e) rapid swelling of the airway that can block breathing.

C -- inflammation of the alveoli which interferes with gas exchange.

A fungal species which can grow in varied climates and under diverse conditions is termed (a) normal. (b) endemic. (c) ubiquitous. (d) mycosis. (e) microbiotic.

C -- ubiquitous

Which of the following actions would most likely result in exposure to Hantavirus within the United States? (a) Inhalation of respiratory droplets from infected pigs (b) Being bitten by a sand fly carrying the Hantavirus pathogen. (c) Close physical contact with someone known to be infected with Hantavirus. (d) Cleaning a previously undisturbed barn known to house deer mice

D -- Cleaning a previously undisturbed barn known to house deer mice

Your 10-month-old, pediatric patient presents with sore throat, runny nose, difficulty breathing, tachycardia, and wheezing. The patient received an effective influenza vaccine 4 months ago. Upon evaluation with a stethoscope, crackling is heard during inhalation. Nucleic acid probes reveal that the pathogen has an RNA genome. Your patient is most likely afflicted with which of the following illnesses? (a) Human Parainfluenza Virus-4 (b) Adenovirus (c) Influenza (d) Respiratory Syncytial Virus

D -- Respiratory Syncytial Virus

An elderly patient with no recent hospitalizations presents with shortness of breath, chest pain, a deep productive cough, and evidence of consolidation. Acid-fast and Gram stains are performed on a sputum sample. No acid-fast bacteria are detected but Gram-negative, non-encapsulated bacteria are observed. A likely diagnosis is (a) Mycobacterium avium. (b) Streptococcus pneumoniae. (c) influenza. (d) nontypable Hemophilus influenzae B. (e) Legionnaire's disease.

D -- nontypable Hemophilus influenzae B

Pertussis is characterized by (a) a pneumonia-like infection acquired from air conditioning or water systems. (b) a positive tuberculin skin test. (c) a high fever with a bright red rash across the body. (d) severe coughing attacks where the patient struggles to catch their breath. (e) high prevalence among those who handle birds.

D -- severe coughing attacks where the patient struggles to catch their breath

This disease is caused by strains of Streptococcus pyogenes which produce an erythrogenic toxin due to the presence of a lysogenized bacteriophage. (a) bacterial pneumonia (b) necrotizing fasciitis (c) streptococcal pharyngitis (d) rheumatic fever (e) scarlet fever

E -- scarlet fever

Vaccine prevention of acute respiratory infections (the common cold) is unlikely because (a) humans do not generate a strong immune response to common cold viruses. (b) colds are easily misdiagnosed as something else. (c) antibiotics easily cure the common cold. (d) there is a relatively low social and economic cost associated with the common cold. (e) there are many distinct virus strains and serovars that cause the common cold.

E -- there are many distinct virus strains and serovars that cause the common cold.

The demographic most at risk from respiratory syncytial virus are (a) pet owners. (b) immunocompromised individuals. (c) smokers. (d) the elderly. (e) young children.

E -- young adults