Which patient has the greatest risk for extracellular fluid volume (ECV) deficit?

A) A female with Crohn's disease
B) A male with peptic ulcer disease
C) An infant with fever and vomiting
D) An adolescent with acute appendicitis

Fever increases insensible water loss through the skin and lungs.Infants and very young children have relatively more body surface area and higher percentage of body water than older children and adults.They have greater water needs and immature kidneys.Infants are at greater risk for ECV deficit and hypernatremia because their body water loss is proportionately greater per kilogram of weight.Although acute appendicitis may cause vomiting and an active episode of Crohn's disease may cause diarrhea,adolescents and young adults have less risk of ECV deficit than an infant.An older adult has increased risk of ECV deficit if there is a large fluid output; however,peptic ulcer disease ordinarily does not cause a large fluid output.