<prompt> Flag hair sign is seen inKwashiorkorMarasmusScurvyPellagra  <response>: Ans. a KwashiorkorRef: Nelsons Pedia, 19th ed. Ch 670 kwashiorkorDisease due to decreased protein and caloric intake.Clinical Features are: Hypoalbuminemia which leads to pedal edema Hepatomegaly- Hallmark feature of kwashiorkor Skin: Sun-exposed skin is relatively spared, as are the feet and dorsal aspects of the hands; Hypo pigmentation Hair and Nail: Nails are thin and soft, and hair is sparse, thin, and depigmented, sometimes displaying a flag sign of alternating light and dark bands that reflect alternating periods of adequate and inadequate nutrition. Apathy Lack of appetite PELLAGRA:This presents with edema, erythema, and burning of sun-exposed skin on the face, neck, and dorsal aspects of the hands, forearms, and feet SCURVY VITAMIN C OR ASCORBIC ACID DEFICIENCY: This presents initially with follicular hyperkeratosis and coiling of hair on the upper arms, back, buttocks, and lower extremities. Perifollicular erythema and hemorrhage, swollen, erythematous gums; stomatitis; and subperiosteal hematomas are also seen. 