The most common primary cause of diaper rash is which of the following?

• A. Candida albicans
• B. Bacterial infection
• C. Excessive exposure to moisture
• D. Repeated contact with feces and urine

Answer: (C)

Excessive exposure to moisture drives diaper rash because damp skin under the diaper becomes macerated and its protective barrier is compromised. The combination of urine and stool creates an irritant environment, and with added friction from the diaper, the skin reddens and inflames. This irritant contact dermatitis is the most common cause. Candida infection can occur but usually as a secondary complication on already irritated skin and often shows satellite lesions rather than the diffuse redness seen with simple irritant dermatitis. Repeated contact with feces and urine increases the risk, but moisture is the main initiating factor.