A 19-yr-old woman presents with fever, rash and cough, and is pyrexial, tachycardic and tachypnoeic. She has a florid erythematous rash on her face, trunk and arms, with scattered whitish papular lesions on the buccal mucosa.
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What is the most likely Dx?
A. Meningococcaemia
B. Rubella
C. Parvovirus B19
D. Secondary syphilis
E. Measles
Answer: E. Measles
Discussion: Adult measles is unusual except in non-immunised persons. The description of this Pt’s rash is classical: the rash is maculopapular, starts on the face and migrates caudally; Koplik’s spots are present in the mouth.
In contrast, meningococcaemia is a petechial/purpuric macular rash with no buccal lesions, and there is no typical migratory pattern.
Rubella is possible, but the lesions are smaller and not intense or darkly coloured: they can also spread caudally but there is no desquamation.
Parvovirus infection produces the typical raised erythema on the cheeks (‘slapped cheek’) and usually occurs in young children: bizarre variations in the rash are sometimes seen.
The rash of secondary syphilis usually affects the upper trunk, palms and soles and flexural extremities. Mucosal lesions are usually erythematous and coalesce (‘snail track’ulcers).
What is the most likely Dx?
A. Meningococcaemia
B. Rubella
C. Parvovirus B19
D. Secondary syphilis
E. Measles
Answer: E. Measles
Discussion: Adult measles is unusual except in non-immunised persons. The description of this Pt’s rash is classical: the rash is maculopapular, starts on the face and migrates caudally; Koplik’s spots are present in the mouth.
In contrast, meningococcaemia is a petechial/purpuric macular rash with no buccal lesions, and there is no typical migratory pattern.
Rubella is possible, but the lesions are smaller and not intense or darkly coloured: they can also spread caudally but there is no desquamation.
Parvovirus infection produces the typical raised erythema on the cheeks (‘slapped cheek’) and usually occurs in young children: bizarre variations in the rash are sometimes seen.
The rash of secondary syphilis usually affects the upper trunk, palms and soles and flexural extremities. Mucosal lesions are usually erythematous and coalesce (‘snail track’ulcers).