Failure to thrive (FTT), also known as weight faltering or faltering growth, indicates insufficient weight gain or absence of appropriate physical growth in children. FTT is usually defined in terms of weight, and can be evaluated either by a low weight for the child's age, or by a low rate of increase in the weight.
The term "failure to thrive" has been used in different ways, as no single objective standard or universally accepted definition exists for when to diagnose FTT. One definition describes FTT as a fall in one or more weight centile spaces on a World Health Organization (WHO) growth chart depending on birth weight or when weight is below the 2nd percentile of weight for age irrespective of birth weight. Another definition of FTT is a weight for age that is consistently below the fifth percentile or weight for age that falls by at least two major percentile lines on a growth chart. While weight loss after birth is normal and most babies return to their birth weight by three weeks of age, clinical assessment for FTT is recommended for babies who lose more than 10% of their birth weight or do not return to their birth weight after three weeks. Failure to thrive is not a specific disease, but a sign of inadequate weight gain.
In veterinary medicine, FTT is also referred to as ill-thrift.
Signs and symptoms Failure to thrive is most commonly diagnosed before two years of age, when growth rates are highest, though it can present among children and adolescents of any age. Caretakers may express concern about poor weight gain or smaller size compared to peers of a similar age. Physicians often identify FTT during routine office visits, when a child's growth parameters such as height and weight are not increasing appropriately on growth curves. When a child falls two or more standard deviations below the median weight-for-height for their age, they are wasting, whereas a child is stunting when their height falls two or more standard deviations below the median height-for-age. Wasting often indicates acute undernutrition, while stunting manifests following chronic undernutrition. Other signs and symptoms may vary widely depending on the etiology of FTT.
The characteristic pattern seen with children with inadequate nutritional intake is an initial deceleration in weight gain, followed several weeks to months later by a deceleration in stature, and finally a deceleration in head circumference. Inadequate caloric intake could be caused by lack of access to food, or caretakers may notice picky eating habits, low appetite, or food refusal. FTT caused by malnutrition could also yield physical findings that indicate potential vitamin and mineral deficiencies, such as scaling skin, spoon-shaped nails, cheilosis, or neuropathy. Lack of food intake by a child could also be due to psychosocial factors related to the child or family. Screening patients and their caretakers for psychiatric conditions such as depression or anxiety is vital, as well as for signs and symptoms of child abuse, neglect, or emotional deprivation.
Children who have FTT caused by a genetic or medical problem may have differences in growth patterns compared to children with FTT due to inadequate food intake. A decrease in length with a proportional drop in weight can be related to long-standing nutritional factors or genetic or endocrine causes. Head circumference, as well, can be an indicator for the etiology of FTT. If head circumference is affected initially in addition to weight or length, other factors are more likely causes than inadequate intake. Some of these include intrauterine infection, teratogens, and some congenital syndromes.
Children who have a medical condition causing FTT may have additional signs and symptoms specific to their condition. Fetal alcohol syndrome (FAS) has been associated with FTT, and can present with characteristic findings including microcephaly, short palpebral fissures, a smooth philtrum and a thin vermillion border. Disorders that cause difficulties absorbing or digesting nutrients, such as Crohn's disease, cystic fibrosis, or celiac disease, can present with abdominal symptoms. Symptoms can include abdominal pain, abdominal distention, hyperactive bowel sounds, bloody stools, or diarrhea.
Cause Traditionally, causes of FTT have been divided into endogenous and exogenous causes, which can also be largely grouped into three categories - inadequate caloric intake, malabsorption/caloric retention defect, and increased metabolic demands.
Endogenous (or "organic")Endogenous causes are due to physical or mental issues affecting the child. These causes include various inborn errors of metabolism. Problems with the gastrointestinal system such as excessive gas and acid reflux are painful conditions which may make the child unwilling to take in sufficient nutrition. Cystic fibrosis, diarrhea, liver disease, anemia or iron deficiency, Crohn's disease, and coeliac disease make it more difficult for the body to absorb nutrition. Other causes include physical deformities such as cleft palate and tongue tie that impede food intake. Additionally, allergies such as milk allergies can cause endogenous FTT. FAS has also been associated with failure to thrive. Additional, medical conditions including parasite infections, urinary tract infections, other fever-inducing infections, asthma, hyperthyroidism and congenital heart disease may raise energy needs of the body and cause greater difficulty taking in sufficient calories to meet the higher caloric demands, leading to FTT. Exogenous (or "nonorganic") Exogenous causes are due to caregiver actions, whether unintentional or intentional. Examples include physical inability to produce enough breastmilk, inappropriate feeding schedules or feeding technique, and mistakes made in formula preparation. In developing countries, conflict settings, and protracted emergencies, exogenous FTT may more commonly be caused by chronic food insecurity, lack of nutritional awareness, and other factors beyond the caregiver's control. As many as 90% of failure to thrive cases are non-organic. Mixed Both endogenous and exogenous factors may co-exist. For instance, a child who is not getting sufficient nutrition for endogenous reasons may act content so that caregivers do not offer feedings of sufficient frequency or volume. Yet, a child with severe acid reflux who appears to be in pain while eating may also make a caregiver hesitant to offer sufficient feedings.
Inadequate caloric intake Inadequate caloric intake indicates that an insufficient amount of food and nutrition is entering the body, whether due to lack of food, anatomical differences causing difficulty eating, or psychosocial reasons for decreased food intake. +CauseDescription/presentationMechanismEpidemiologyPoverty/inadequate food supplyInadequate food available for childDecreased food intakeMost common cause of failure to thrive globallyInadequate breast milk supply/ineffective latchingMother is unable to produce enough breast milk or infant is unable to latch properly during breastfeedingInsufficient breastfeedingImproper preparation of formulaFormula is not prepared or mixed properlyInsufficient nutrition from formula feedingPostpartum depression/maternal depressionMother experiences low mood, persistent sadness, and/or loss of interest or pleasure in activitiesMothers with depression are more likely to have breastfeeding difficulties and may have decreased desire to interact with their children, which may lead to decreased feeding1 in 10 women in the US experience symptoms of depression
1 in 8 women experience symptoms of postpartum depression, or depression after childbirthChild neglectCaretakers fail to provide adequate care to the childCaretakers do not adequately feed the childPrevalence of neglect in non-organic FTT may be as high as 5-10%Cerebral palsyDisturbance in the developing fetal or infant brain leads to difficulties and delays in cognition, motor movement and coordination, and other aspects of developmentDecreased motor function and coordination leads to difficulty feedingAffects about 3.6/1000 childrenCleft lip/cleft palateDuring fetal development, parts of the mouth/lips do not fuse properly, causing an anatomical defectImpaired oral motor coordination and poor suck causes difficulty feedingOccurs in about 1 in 600 to 800 live birthsGastroesophageal reflux diseaseRegurgitation of food causes discomfort and irritabilityDiscomfort and pain after eating may cause poor appetite or refusal to feedOccurrence peaks at about 4 months of agePyloric stenosisAbnormal thickening of the opening between the stomach and small intestine blocks food from flowing through the gastrointestinal tract, causing projectile vomitingProjectile vomiting after eating and inability of food to enter small intestine leads to dehydration and weight lossInfant is usually well at birth, and pyloric stenosis usually presents at 3–6 weeks of ageToxins causing gastrointestinal problemsToxins such as lead can cause decreased appetite, constipation, or abdominal painGastrointestinal problems and discomfort can lead to decreased appetite or refusal to eatAvoidant/restrictive food intake disorder (ARFID)Psychiatric condition in which individuals avoid eating certain foods or restrict the amount of food they eat; may be due to sensory sensitivity, a traumatic experience with eating, or another causeFood avoidance or restriction leads to inadequate nutritional intake
Malabsorption/caloric retention defect Malabsorption and caloric retention defects cause the body to the unable to absorb and use nutrients from food, despite an adequate amount of food physically entering the body. +CauseDescription/presentationMechanismEpidemiologyInborn errors of metabolismGenetic conditions that interfere with the utilization of nutrients for energy; include conditions such as galactosemia, glycogen storage diseaseDisruption in the breakdown of nutrients and to utilization of nutrients to produce energyCow's milk protein allergyAllergy to a protein in cow's milk, causing symptoms such as skin reactions, wheezing, difficulty breathing, diarrhea, or vomiting after ingestion of cow's milkInability to drink milk leads to poor growth; discomfort after drinking milk may also lead to food refusalAffects 2-6% of children, primarily during the first year of life, though many children outgrow the conditionCeliac diseaseAutoimmune disease in which ingestion of foods containing gluten leads to symptoms including diarrhea, abdominal pain, and bloatingDamage to intestinal lining leads to problems with nutrient uptakePrevalence of 0.5-1% among the general populationShort bowel syndromeLoss of functioning intestines due to surgery, congenital anatomical differences, or other diseaseShortage of functioning intestines leads to malabsorption of nutrientsNecrotizing enterocolitis is the most common cause in infancyCystic fibrosisDisorder in production and clearance of mucus leads to problems with lung and gastrointestinal functionProblems with mucus clearance leads to issues with the pancreas and other gastrointestinal organs, leading to malabsorption of nutrientsAffects 1 in 2500 Caucasian newbornsBiliary atresiaFailure of development of the bile ducts that help carry enzymes necessary for digestion of fats in food
Causes yellowing of the skin (jaundice), pale stools, and dark urine in the infantUnderdevelopment of bile ducts leads to malabsorption of fats, difficulties with absorbing vitamins and other nutrients, and poor oral intake of foodPancreatic insufficiencyInability of pancreas to produce sufficient enzymes necessary for digestion and absorption of nutrients, leading to symptoms such as chronic diarrhea and greasy stoolsMalabsorption of fats and inability to digest nutrients such as fat-soluble vitamins leads to poor weight gain
Increased metabolic demand