The term “failure to thrive “(FTT) first appeared in the literature more than 80 years ago, and although it continues to be widely used, it has no precise definition. Recent terms to describe FTT include undernutrition, malnutrition, and faltered growth. In 2017, guidelines by the National Institute for Healthcare and Excellence in the United Kingdom were published to aid in recognizing, assessing, and monitoring of “faltering growth” in infants and children in the United Kingdom.1 With a lack of any other formal practice recommendations, however, clinical practice is variable, with an overuse of resources, including unnecessary laboratory testing, subspecialist referrals, and hospitalization.2-4
Historically, FTT has been classified as organic and nonorganic, but it is now recognized that only a small minority of children with FTT have an underlying organic cause. Instead, FTT often has a multifactorial etiology involving a complex interaction between medical, nutritional, emotional, and social issues. Although this range of contributing factors can pose a diagnostic challenge, the evaluation and coordination of a management plan for FTT can often be done successfully by providers across the continuum of pediatric care when guided by findings from a detailed history and thorough physical examination.
With a focus on promoting high-value care for patients, this article presents a practical, systematic approach that pediatric providers can use for the differential diagnosis and management of FTT.
Failure to thrive has classically been identified when a child’s weight drops off the standardized weight curve before and to a greater extent than the length/height (Figure).5 Its recognition depends on reliable serial measurements for growth assessment. Individuals gathering data must be properly trained and use appropriate equipment with a standardized technique. Stature (length/height) should be measured with the child lying supine on a length board for children aged 0 to 2 years and using a stadiometer for older children. Weight should be determined using a digital scale, and head circumference also should be measured in children aged younger than 3 years.
Data should be recorded and plotted on a standardized growth chart for age and gender or using another appropriate chart when special circumstances exist (eg. premature birth, genetic syndrome). The Centers for Disease Control and Prevention (CDC) recommends using the World Health Organization’s weight-for-length growth chart for children aged younger than 2 years and the CDC body mass index (BMI) growth chart for older children.6
Diagnostic evaluation is key in determining underlying cause(s) for FTT and appropriate management. Pediatric providers should initiate the diagnostic evaluation for FTT by taking a detailed feeding/eating history and performing a clinical, developmental, and social assessment that aims to identify issues that can lead to undernutrition. These etiologies can then be categorized as inadequate caloric intake, inadequate caloric absorption/usage, and/or increased metabolic demands (Table 1).7
History and physical examination
A dietary history may be obtained through a 24-hour recall provided by the parent/caregiver. Whenever possible, providers should enlist the help of a dietitian who can conduct a more formal assessment including calorie counts.
The patient history should identify types of foods and calories consumed along with frequency of meals and snacks. It also should include questions to determine the child’s behavior at feedings/meal times and parental reactions and ideas about nutrition. Some common issues underlying inadequate calories include excessive intake of juice or other beverages that provide poor nutrition and limit appetite for other foods, and improper formula preparation. Mothers who are breastfeeding should be asked about their diet and use of medications, alcohol, or other substances that can affect milk production and let-down.
Psychosocial issues should be investigated to determine if the child is not being provided with adequate food because of neglect/abuse or as a consequence of parental economic, intellectual, or mental health problems.
A good history also can help identify clues of an underlying medical cause for FTT by asking about symptoms of gastrointestinal illnesses—vomiting, reflux, diarrhea, constipation, blood or mucus in the stool; respiratory signs—breathing difficulty, chronic cough, snoring; or recurrent infections. In addition, a thorough family history should be obtained to understand the stature and growth pattern of siblings, parents, and grandparents as well as identifying illnesses such as food allergies, genetic diseases, inflammatory bowel disease, celiac disease, asthma, and cystic fibrosis.The physical examination should include looking for physical impediments to feeding and swallowing, such as cleft lip/palate, oral abscesses, or enlarged tonsils/adenoids; dysmorphic features indicative of a genetic disorder; abdominal distention or organomegaly; neurologic signs of developmental delay; and bruises or other evidence of trauma and abuse. Observation of the parent-child interaction in general and during feeding is also a key part of the physical examination.
1. National Institute for Health and Care Excellence. Faltering growth: recognition and management of faltering growth in children. NICE guideline. Available at: https://www.nice.org.uk/guidance/ng75/resources/faltering-growth-recognition-and-management-of-faltering-growth-in-children-pdf-1837635907525. Published September 27, 2017. Accessed March 19, 2018.
2. Adedoyin O, Gottlieb B, Frank R, et al. Evaluation of failure to thrive: diagnostic yield of testing for renal tubular acidosis. Pediatrics. 2003;112(6 pt 1):e463.
3. Sills RH. Failure to thrive. Am J Dis Child. 1978;132(10):967-969.
4. Berwick DM, Levy JC, Kleinerman R. Failure to thrive: diagnostic yield of hospitalisation. Arch Dis Child. 1982;57(5):347-351.
5. Al Nofal A, Schwenk WF. Growth failure in children: a symptom or a disease? Nutr Clin Pract. 2013;28(6):651-658.
6. Centers for Disease Control and Prevention. National Center for Health Statistics. Growth charts. Available at: https://www.cdc.gov/growthcharts/. Updated September 9, 2010. Accessed March 19, 2018.
7. Vachani JG. Failure to thrive. In: American Academy of Pediatrics Section on Hospital Medicine; Gershel JC, Rauch DA, eds. Caring for the Hospitalized Child: A Handbook of Inpatient Pediatrics. 2nd ed. Elk Grove Village, IL: American Academy of Pediatrics; 2017:569-576.
8. Ficicioglu C, An Haack K. Failure to thrive: when to suspect inborn errors of metabolism. Pediatrics. 2009;124(3):972-979.
9. Becker P, Carney LN, Corkins MR, et al; Academy of Nutrition and Dietetics: American Society for Parenteral and Enteral Nutrition. Consensus statement of the Academy of Nutrition and Dietetics/American Society for Parenteral and Enteral Nutrition: indicators recommended for the identification and documentation of pediatric malnutrition (undernutrition). Nutr Clin Pract. 2015;30(1):147-161.
10. Thompson RT, Bennett WE Jr, Finnell SM, Downs SM, Carroll AE. Increased length of stay and costs associated with weekend admissions for failure to thrive. Pediatrics. 2013;131(3):e805-e810.