failure to thrive (FTT)

failure to thrive (FTT) /fāl″yər/ [L, fallere, to deceive; ME, thriven, to grasp] , the abnormal delay of growth and development of an infant resulting from conditions that interfere with normal metabolism, appetite, and activity. Causative factors include chromosomal abnormalities, as in Turner’s syndrome and the various trisomies; major organ system defects that lead to deficiency or malfunction; systemic disease or acute illness; physical deprivation, primarily malnutrition; and various psychosocial factors, as in severe cases of maternal deprivation syndrome. Metabolic disturbances of short duration, as occur during acute illness, usually have no long-term effects on development and are usually followed by a period of rapid growth. Prolonged nutritional deficiency may cause permanent and irreversible delay of physical, mental, or social development.