,
, FNP 593 WEEK 2 PEDIATRIC ILLNESS |
2026 UPDATE | WITH COMPLETE
SOLUTIONS.
🦠 SECTION 1: VIRAL EXANTHEMS & INFECTIOUS
DISEASES (Questions 1–15)
Question 1
A 7-year-old child presents with a "slapped cheek" facial rash that
appeared suddenly. Two days later, the parents note a lacy,
reticular rash on the child's trunk and extremities. The child had
mild cold symptoms before the rash appeared. What is the most
likely diagnosis?
A) Roseola (HHV-6)
B) Fifth disease (erythema infectiosum)
C) Scarlet fever
D) Rubella
E) Measles (rubeola)
Correct Answer: B) Fifth disease (erythema infectiosum)
Rationale: The classic presentation of Fifth disease (caused by Parvovirus
B19) is a three-stage rash:
1. "Slapped cheek" facial rash – bright red, confluent erythema on
both cheeks
2. Lacy, reticular rash on trunk and extremities – appears 1–4 days
after facial rash
3. Rash may come and go for several weeks, exacerbated by sun, heat,
or exercise
The child also typically has mild prodromal symptoms (low-grade fever,
coryza, headache). Roseola (A) presents with high fever for 3–5 days
, followed by a maculopapular rash that appears as fever resolves.
Scarlet fever (C) presents with sandpaper-like rash, strawberry tongue,
and pharyngitis. Rubella (D) presents with postauricular
lymphadenopathy and a pink maculopapular rash that starts on the
face and spreads downward but is not lacy. Measles (E) presents with
cough, coryza, conjunctivitis (3 C's), Koplik spots, and a confluent red
maculopapular rash starting at the hairline .
Question 2
The causative organism for Fifth disease is:
A) Human herpesvirus 6 (HHV-6)
B) Parvovirus B19
C) Group A Streptococcus
D) Rubella virus
E) Measles virus
Correct Answer: B) Parvovirus B19
Rationale: Parvovirus B19 is a single-stranded DNA virus that
causes erythema infectiosum (Fifth disease). It is transmitted via
respiratory secretions and primarily affects school-aged children (ages 5–15
years). The virus targets erythroid progenitor cells in the bone marrow,
causing a transient arrest in red blood cell production. In healthy children,
this is well-tolerated. However, in patients with hemolytic anemias (e.g.,
sickle cell disease), infection can trigger aplastic crisis. Pregnant women
exposed to Parvovirus B19 are at risk for fetal hydrops .
Question 3
A 9-month-old infant presents with a high fever (103°F) for 3 days.
The infant is otherwise well-appearing, playful, and has no source of
infection on exam. On day 4, the fever abruptly resolves, and the
infant develops a pink maculopapular rash on the trunk and neck.
What is the most likely diagnosis?
, FNP 593 WEEK 2 PEDIATRIC ILLNESS |
2026 UPDATE | WITH COMPLETE
SOLUTIONS.
🦠 SECTION 1: VIRAL EXANTHEMS & INFECTIOUS
DISEASES (Questions 1–15)
Question 1
A 7-year-old child presents with a "slapped cheek" facial rash that
appeared suddenly. Two days later, the parents note a lacy,
reticular rash on the child's trunk and extremities. The child had
mild cold symptoms before the rash appeared. What is the most
likely diagnosis?
A) Roseola (HHV-6)
B) Fifth disease (erythema infectiosum)
C) Scarlet fever
D) Rubella
E) Measles (rubeola)
Correct Answer: B) Fifth disease (erythema infectiosum)
Rationale: The classic presentation of Fifth disease (caused by Parvovirus
B19) is a three-stage rash:
1. "Slapped cheek" facial rash – bright red, confluent erythema on
both cheeks
2. Lacy, reticular rash on trunk and extremities – appears 1–4 days
after facial rash
3. Rash may come and go for several weeks, exacerbated by sun, heat,
or exercise
The child also typically has mild prodromal symptoms (low-grade fever,
coryza, headache). Roseola (A) presents with high fever for 3–5 days
, followed by a maculopapular rash that appears as fever resolves.
Scarlet fever (C) presents with sandpaper-like rash, strawberry tongue,
and pharyngitis. Rubella (D) presents with postauricular
lymphadenopathy and a pink maculopapular rash that starts on the
face and spreads downward but is not lacy. Measles (E) presents with
cough, coryza, conjunctivitis (3 C's), Koplik spots, and a confluent red
maculopapular rash starting at the hairline .
Question 2
The causative organism for Fifth disease is:
A) Human herpesvirus 6 (HHV-6)
B) Parvovirus B19
C) Group A Streptococcus
D) Rubella virus
E) Measles virus
Correct Answer: B) Parvovirus B19
Rationale: Parvovirus B19 is a single-stranded DNA virus that
causes erythema infectiosum (Fifth disease). It is transmitted via
respiratory secretions and primarily affects school-aged children (ages 5–15
years). The virus targets erythroid progenitor cells in the bone marrow,
causing a transient arrest in red blood cell production. In healthy children,
this is well-tolerated. However, in patients with hemolytic anemias (e.g.,
sickle cell disease), infection can trigger aplastic crisis. Pregnant women
exposed to Parvovirus B19 are at risk for fetal hydrops .
Question 3
A 9-month-old infant presents with a high fever (103°F) for 3 days.
The infant is otherwise well-appearing, playful, and has no source of
infection on exam. On day 4, the fever abruptly resolves, and the
infant develops a pink maculopapular rash on the trunk and neck.
What is the most likely diagnosis?
