Infectious Disease

Question 1

An unvaccinated 5-year-old boy presents to his pediatrician with a sore throat for the past three days. On oropharyngeal examination, a white-gray adherent membrane is seen. It bleeds with scraping. Rapid strep test is negative. Which of the following is the most likely diagnosis?

A) Diphtheria
B) Group A streptococcal pharyngitis
C) Infectious mononucleosis
D) Viral pharyngitis

Answer 1

Diptheria

Question 2

Children less than 5 are at an increased risk for atypical mycobacterial disease due to putting things in their mouth. Most cases are asymptomatic. What will be found on exam?

Answer 2

Atypical mycobacterial infections in children are most frequently located in the superior anterior cervical or submandibular nodes.

Usually lack constitutional symptoms.

Question 3

Who should be tested for mycobacterium avium complex (MAC)?

What is the treatment for MAC?

Answer 3

HIV patients with CD4 < 50

Immunocompentent patients are rarely diagnosed with mycobacterium avium complex

Clarithromycin and ethambutol for at least 12 months

Question 4

What is the treatment for mycobacterium kansasii?

Answer 4

Rifampin + ethambutol

Question 5

An unvaccinated boy presents to the pediatrician with bilateral parotid gland swelling. His mother states that the swelling was preceded by fever, fatigue, and decreased appetite. Which of the following describes the causative pathogen of this condition?

A) The condition is caused by a gram-negative bacterial pathogen
B) The condition is caused by a gram-positive bacterial pathogen
C) The condition is caused by a virus from the Herpesviridae family
D) The condition is caused by a virus from the Paramyxovirus genus

Answer 5

The patient has mumps which is caused by the paramyxovirus

Question 6

A 15-year-old boy presents to his pediatrician with fever and sore throat for the last three days. He also reports fatigue and has missed school and football practice all week. A strep test is negative, but a Monospot test is positive. Which of the following is the most important recommendation to give the family?

A) Amoxicillin treatment for 10 days
B) Antibody testing to confirm infection
C) No return to contact sports for at least four weeks
D) No return to school for at least one week

Answer 6

No return to contact sports for at least four weeks

Question 7

A 2-year-old boy presents to the emergency room with one day of fever and stridor. The patient is leaning forward, drooling, and is in distress. Direct visualization of the oropharynx is not possible due to patient discomfort. Oxygen saturation is 88%, pulse is 120 beats per minute, and temperature is 101.2º F. A lateral X-ray of the neck reveals a radiolucent protrusion of the anterior hypopharynx (“thumbprint sign”). Which of the following is the most likely diagnosis?

A) Acute laryngotracheitis
B) Bacterial epiglottitis
C) Pharyngeal foreign body
D) Retropharyngeal abscess

Answer 7

Bacterial epiglotitis

Question 8

What is the most common virus transmitted from a pregnant woman to a infant (vertical transmission)?

Answer 8

Herpes Human Virus 5 - Cytomegalovirus

Question 9

What common exanthem is caused by HHV 6?

Answer 9

Roseola Infantum (6th disease)

Question 10

What is the most common cause of pancreatitis in children?

Answer 10

Mumps

Question 11

When is the MMR vaccine given?

Answer 11

Given at 12-15 months then again at age 4-6

Question 12

What is the pathophysiology of pertussis?

Answer 12

Caused by the gram-negative bacteria Bordatella Pertusis

Question 13

What are the stages of pertussis?

How is pertussis diagnosed?

Answer 13

• Catarrhal stage: cold-like symptoms, poor feeding, and sleeping
• Paroxysmal stage: high-pitched “inspiratory whoop”
• Convalescent stage: residual cough (100 days)

Nasopharyngeal swab

Question 14

What is the treatment for pertussis?

Answer 14

Macrolide abx (erythromycin/azithromycin) + supportive care

Can give albuterol or steroids

Question 15

When should pregnant mothers receive the pertussis vaccine?

Answer 15

Expectant mothers should get Tdap during each pregnancy, usually at 27-36 weeks

Question 16

What is the vaccine schedule for Tdap?

Answer 16

Vaccination: 5 doses – 2, 4, 6, 15-18 mo, 4-6yrs (DTap)

11-18 yo = 1 dose Tdap

Question 17

Pinworm classically causes symptoms at what time of day?

What test is used to diagnose pinworm?

Answer 17

The scotch tape testAt night

Question 18

What is the treatment for pinworm?

Answer 18

Albendazole or mebendazole

Question 19

What childhood viral exanthem is the only one to start on the trunk?

Answer 19

Roseola (sixth disease or baby measles)

Question 20

A 5-year-old boy presents with a fever of 102°F, headache, and myalgia. Physical examination reveals a maculopapular rash that started on his face and is now spreading to his trunk and limbs. His mother reports that he has not been vaccinated according to the recommended schedule. Which of the following is the most likely diagnosis?

What should be given to reduce morbidity and mortality?

Answer 20

Measles

Vitamin A

Question 21

An 18-month-old girl, who attends daycare, presents with high fever, irritability, and pulling at her right ear. Otoscopic examination shows a bulging tympanic membrane with loss of light reflex. She has a known allergy to penacillins. What is the most appropriate initial management?

Answer 21

Macrolides (Azithromycin or Clarithromycin)

Question 22

A 3-year-old boy is brought to the clinic with a barking cough, stridor, and hoarseness that started suddenly last night. His parents report that he has had a low-grade fever. He appears anxious and is sitting upright. What is the most likely causative agent?

Answer 22

Parainfluenza virus (this child has croup)

Question 23

A 4-year-old girl is brought to the emergency department with a fever, sore throat, and drooling. She is sitting upright and appears very distressed. What is the most appropriate next step in management?

A) Administer a broad-spectrum antibiotic
B) Immediate intubation
C) Perform a lateral neck X-ray
D) Give a trial of nebulized epinephrine

Answer 23

Perform a lateral neck x-ray

X-ray is needed to confirm the diagnosis of epiglotitis. The child may require intubation in a controlled setting like the OR.

Question 24

A 7-year-old boy presents with fever, headache, and a stiff neck. Kernig’s and Brudzinski’s signs are positive. Which of the following organisms is the most likely cause of these symptoms?

A) Haemophilus influenzae type b
B) Neisseria meningitidis
C) Streptococcus pneumoniae
D) Listeria monocytogenes

Will glucose be elevated, decreased, or normal on CSF cuture?

Answer 24

Neisseria meningitids

Decreased along with increased WBC and protein levels

Question 25

An 8-year-old girl presents with fever, cough, and widespread wheezing on auscultation. A chest X-ray shows patchy infiltrates. She has a history of similar symptoms around the same time last year. What is the most likely diagnosis?

A) Asthma
B) Acute bronchitis
C) Pneumonia
D) Seasonal allergies

Answer 25

Pneumonia (most likely viral due to no fever and multiple patchy infilatrates)

Question 26

A 6-month-old infant presents with fever, irritability, and a bulging fontanelle. The mother reports that the infant has been feeding poorly. Which of the following additional findings would most support a diagnosis of bacterial meningitis?

A) A clear runny nose
B) A rash that blanches with pressure
C) Nuchal rigidity
D) Diarrhea

Answer 26

Nuchal rigidity

Question 27

A 16-year-old girl presents with fever, sore throat, and swollen lymph nodes. Examination reveals tonsillar exudates and enlarged, tender cervical lymph nodes. A rapid strep test is negative. Given her age and symptoms, what is the most appropriate management?

A) Start IV antibiotics immediately
B) Reassess in 24 hours
C) Perform a throat culture
D) Advise symptomatic treatment only

Why should emperic antibiotics not be given?

Answer 27

Perform a throat culture

Given age of patient she is also at high risk for mono

Question 28

A 6-year-old boy presents to the clinic with facial swelling for the past day. He had fever, headache, and generalized malaise for 2 days prior to the development of the facial swelling. The patient has a history of asthma and has not had any childhood vaccinations. Vital signs include a BP of 100/65 mm Hg, HR of 125 bpm, RR of 22/min, T of 102.1°F, and SpO2 of 99% on room air. Physical examination reveals bilateral facial swelling and tenderness in the preauricular area that obscures the angle of the mandible. He has a tachycardic heart rate and regular rhythm and lungs that are clear to auscultation. Oropharyngeal exam reveals mild erythema without tonsillar exudate. What is the most likely diagnosis?

Answer 28

Mumps

Question 29

What is the most common pathogen associated with mastoiditis?

Answer 29

S. pneumoniae

Question 30

A 2-day-old boy who was born yesterday at 39 weeks gestational age by a spontaneous vaginal delivery is admitted to the hospital after birth. His mother had an illness during the first trimester of pregnancy that caused a fever, lymphadenopathy, and a rash that started on the face and then spread to the trunk and extremities. The rash lasted about 3 days. The patient’s vital signs include a BP of 80/40 mm Hg, HR of 160 bpm, RR of 40/min, T of 98.6°F, and SpO2 of 99% on room air. Physical examination reveals a systolic heart murmur and cloudy cornea. Which of the following additional findings is most likely in this patient?

A. Chorioretinitis, hydrocephalus, and intracranial calcifications
B. Oval, coppery-brown lesions on the buttock, posterior thighs, and soles
C. Sensorineural hearing loss
D. Vesicular lesions on an erythematous base on the neck

Answer 30

Sensorineural hearing loss

Sensorineural hearing loss is associated with maternal rubella infection during pregnancy