Staphylococcal scalded skin syndrome is caused predominantly by phage group 2 staphylococci, particularly strains 71 and 55, which are present at localized sites of infection. Of the following, the MOST common focus of infection is

Correct Answer: A

Rationale: The nasopharynx is the most common site of initial infection in staphylococcal scalded skin syndrome, making A correct.

Correct Answer: C

Rationale: Scabies mites survive off the host for 2-3 days, making transmission via fomites rare but possible, and C correct.

Correct Answer: D

Rationale: Vitamin B1 (thiamine) does not induce acneiform lesions, unlike the others, making D the exception.

Correct Answer: D

Rationale: Pilomatricomas are the most common benign nodules in children, often on the face, making D correct.

Correct Answer: B

Rationale: The standard zinc replacement dose for acrodermatitis enteropathica is 3 mg/kg/day, making B correct.