Which signs indicate dehydration in an infant?

• A. Poor skin turgor, sunken fontanel, and dry mucous membranes
• B. Normal turgor, full fontanel, moist mucous membranes
• C. Edema with weight gain
• D. Increased urine output

Answer: (A)

In an infant, dehydration most reliably shows up as poor skin turgor, a sunken fontanel, and dry mucous membranes. Poor skin turgor reflects loss of extracellular fluid and reduced skin elasticity. A sunken fontanel is a classic sign in babies because their fontanelles are sensitive indicators of fluid status; when dehydrated, the soft spot can appear noticeably depressed. Dry mucous membranes indicate reduced oral secretions from lower hydration levels. Together, these signs point to fluid deficit rather than excess.

In contrast, normal skin turgor with a full fontanel and moist mucous membranes suggests adequate hydration. Edema with weight gain indicates fluid overload rather than dehydration. Increased urine output would not align with dehydration; it can occur with other conditions or diuretic use.