What is the cardinal physical sign of Parvo B19 infection (fifth disease)?

What is the cardinal physical sign of Parvo B19 infection (fifth disease)?

• A. Koplik spots
• B. Strawberry tongue
• C. Slapped cheek rash
• D. Petechiae

Answer: (D)

The main idea here is recognizing the distinctive facial presentation of parvovirus B19 infection. Erythema infectiosum most characteristically produces a bright red, flushed appearance on the cheeks that looks as if the person has been slapped—a “slapped-cheek” rash. This facial redness is the hallmark sign, often followed by a fine, lacy rash on the trunk and limbs. Koplik spots are small white spots on the mucosa seen with measles, not parvovirus B19. A strawberry tongue is associated with scarlet fever or Kawasaki disease, not fifth disease. Petechiae are tiny red or purple spots from bleeding under the skin and aren’t the typical presentation of parvovirus B19 infection. So the slapped-cheek rash is the best clue to identify fifth disease.

The main idea here is recognizing the distinctive facial presentation of parvovirus B19 infection. Erythema infectiosum most characteristically produces a bright red, flushed appearance on the cheeks that looks as if the person has been slapped—a “slapped-cheek” rash. This facial redness is the hallmark sign, often followed by a fine, lacy rash on the trunk and limbs.

Koplik spots are small white spots on the mucosa seen with measles, not parvovirus B19. A strawberry tongue is associated with scarlet fever or Kawasaki disease, not fifth disease. Petechiae are tiny red or purple spots from bleeding under the skin and aren’t the typical presentation of parvovirus B19 infection.

So the slapped-cheek rash is the best clue to identify fifth disease.