What is the Differential Diagnosis of Failure to Thrive?

Patient Presentation
A 17-month-old male was admitted for nutritional resuscitation. According to records, his weight tracked around the 3rd percentile for the first 6 months of life, and his height as 25-50%. At 14 months his weight was 50% for a 5 month old, height was 50% for a 9 month old and head circumference was 50% for a 6 month old. He had a complex social situation and was currently in foster care. Unfortunately there were ongoing problems with the foster care placement also. The social worker who brought him to clinic earlier in the day stated that he takes 3 meass and 5 cans of Pediasure®/day per foster care. There is no history of emesis, reflux, diarrhea, constipation, or food refusal. The past medical history showed that he was a full term infant with no problems prenatally or postnatally and his mother received routine prenatal care. He had a previous evaluation by a feeding/speech and language specialist that found no problems with oromotor feeding or swallowing but was severely delayed in speech. He was receiving speech therapy. He had had an extensive laboratory evaluation in the specialty nutrition clinic at 15 months of age, that showed no obvious cause of his poor growth. The family history showed that his mother’s height is 4 foot 10 inches, and father is 5 foot 7 inches. There are family members with developmental delay, hypothyroidism, and learning problems.

The pertinent physical exam shows a small, thin child with little subcutaneous fat. He is smiling and interactive, but he only babbles consonants and vowels without recognizable words. Gross motor and fine motor skills appear normal for age. His weight was 7.84 kg (50% for a 6 month old), height was 74.5 cm (50% for a 12 month old) and head circumference was 45 cm (50% for an 8 month old). This was only 1 g/day weight gain since his last visit. His physical examination was normal otherwise. The diagnosis of failure to thrive with failed outpatient management, language developmental delay and a complex social situation was made. The patient was started on a general toddler diet with strict calorie count which included 6 small meals and 3 servings of Pediasure®/day. He had no water or juice and a total of 25 minutes maximum time allotted for all meals. A behavorial psychologist also worked with him regarding feeding. Speech continued his therapy. The patient’s clinical course showed that he was eventually discharged back to his biological parents with community social service support. He continued to have some problems with feeding over the next 3 years. Consistent calorie boosting at home and daycare caused him to regain and stabilize his weight and height at the 5th percentile. His clinical course also showed a growth pattern consistent with genetic short stature in addition to the resolving failure to thrive.

Failure to Thrive (FTT) is defined as persistent weight below the 3rd percentile for age in infants and young children. The associated terms “Failure to gain weight” (FGW) or “Lack of Normal Physiologic Growth and Development” are more precise, especially for children who are not below the 3rd percentile but are losing weight over time and/or crossing percentile lines on their growth curve. For general growth parameters see How Do I Calculate Mid-Parental Height and Other Growth Parameters? About 70-80% of FTT cases have psychosocial problems that are associated with the FTT or the primary cause of the FTT. Children of older ages may also have FTT such as those with psychosocial dwarfism or eating disorders.

Children with FTT have a wide range of appearances from ill and emaciated to well but small, depending on the cause. History and physical examination are the mainstay of diagnosis. A detailed nutritional history including caloric assessment, who feeds the child, type of food offered, when/where food is offered, and weaning are important. Birth history (including possible teratogens and substance abuse), developmental history(including loss of milestones for possible metabolic or genetic abnormality), and past medical history for chronic infections or other medical problems. Family history should including miscarriages or early childhood deaths and also weight/height of parents and siblings (for possible genetic abnormalites). Social history including exploration of stressors are very important. A complete physical examination (including accurate weight, height and head circumferences and their trends) with directed emphasis in areas clued by the history is important. Laboratory evaluation should be limited and guided by the history and physical examination. It should also be staged.

Initial clinical evaluation may include:

  • Albumin
  • CBC, Differential, Platelet count
  • ESR, C-Reactive Protein
  • Electrolytes, BUN, Creatinine
  • PPD with Control
  • Total Protein
  • Urinalysis and Urine pH
  • Stool Guiac (consider fecal fat, stool Clinitest)
  • Dietary Consultation

Other tests which may be ordered depending on clinical suspicion include:

  • ALT, AST
  • Calcium, Phosphorus
  • Iron Studies
  • Lead
  • Thyroid Function Tests
  • Quantitative Immunoglobulins
  • Urine for Reducing Substances, Culture
  • Stool for Malabsorption
  • Stool for Ova and Parasites
  • Bone Radiographs
  • Chest Radiograph
  • Neuroimaging
  • Sweat Test
  • Cardiac Evaluation

Treatment depends on the probable underlying cause of the FTT. If nutritional deficiencies are indicated, appropriate dietary counseling and supplementation are needed. Counseling for psychosocial stressors in the caregivers (and patient) may also be appropriate. Other specific treatments will vary. Patients should be hospitalized for severe malnutrition or dehydration, extreme parental anxiety, or failure of outpatient treatment.

Learning Point
The differential diagnosis of failure to thrive includes:

  • Chronic Disease
    • Cardiac
      • Cardiac Failure
    • Neoplasia
    • Pulmonary
      • Bronchopulmonary Dysplasia
      • Cystic Fibrosis
    • Renal
      • Renal Failure
      • Renal Tubular Acidosis
    • Rheumatology
      • Systemic Lupus Erythematosus
  • Congenital/Genetic/Neurological Disease
    • Cerebral Palsy
    • Craniofacial Abnormalities
    • Fetal Alcohol Syndrome
    • Intrauterine Growth Retardation
    • Mental Retardation
    • Myopathies
    • Neurocutaneous Syndromes
      • Neurofibromatosis
    • Prematurity
    • Primary CNS abnormality
    • Genetic Syndromes
      • Cystic Fibrosis
      • Russell-Silver Syndrome
      • Williams Syndrome
    • Muscle weakness
      • Prader Willi Syndrome
    • Inborn Error of Metabolism
  • Endocrinological Disease
    • Diabetes Mellitus
    • Hypopituitarism
    • Hyperthyroidism
    • Growth hormone Deficiency
  • Gastrointestinal Disease
    • Celiac Disease
    • Chronic Diarrhea
    • Chronic Emesis
    • Esophagitis
    • Gastrointestinal Reflux
    • Inflammatory Bowel Disease
    • Malabsorption
    • Protein Losing Enteropathies
  • Infectious Disease
    • Congenital infections
    • HIV/AIDS
    • Recurrent infections
    • Parasites
    • Tuberculosis
  • Immunological/Rheumagological Disease
    • Immunodeficiencies
  • Other
    • Anemia
    • Heavy Metals
      • Lead
      • Drugs
        • Amphetamine
        • Cocaine
        • Hydantoin
        • Phenobarbital
    • Dental Caries
  • Nutritional Problems
    • Inadequate Calories
    • Inadequate Protein
    • Poor Appetite
    • Maternal Malnutrition
  • Psychiatric Problems
    • Depression
    • Eating Disorders in Patient or Mother
    • Munchausen’s Disease by Proxy
    • Psychosis
  • Social Problems
    • Child Abuse
    • Caregiver/Child Interaction Abnormalities
      • Emotional Deprivation
      • Difficult Child
    • Family Stress
    • Parenting, Ineffective
    • Poverty

Questions for Further Discussion
1. What is the differential diagnosis for short stature?
2. What signs, symptoms or testing may help to distinguish between failure to thrive versus low weight in a child with a chromosomal abnormality?
3. What social services are available locally to assist families with failure to thrive children?

Related Cases

To Learn More
To view pediatric review articles on this topic from the past year check PubMed.

Evidence-based medicine information on this topic can be found at SearchingPediatrics.com, the National Guideline Clearinghouse and the Cochrane Database of Systematic Reviews.

Information prescriptions for patients can be found at MedlinePlus for these topics: Growth Disorders and Infant and Toddler Health.

To view current news articles on this topic check Google News.

To view images related to this topic check Google Images.

Kleinman RE, edit. Pediatric Nutrition Handbook. American Academy of Pediatrics. 6th edit. 2009;601-636.

El-Baba MF, Bassali RW, Benjamin J, Mehta R. Failure to Thrive. eMedicine.
Available from the Internet at http://emedicine.medscape.com/article/985007-overview (rev. 5/4/09, cited 12/10/09).

ACGME Competencies Highlighted by Case

  • Patient Care
    1. When interacting with patients and their families, the health care professional communicates effectively and demonstrates caring and respectful behaviors.
    2. Essential and accurate information about the patients’ is gathered.
    4. Patient management plans are developed and carried out.
    7. All medical and invasive procedures considered essential for the area of practice are competently performed.
    8. Health care services aimed at preventing health problems or maintaining health are provided.
    9. Patient-focused care is provided by working with health care professionals, including those from other disciplines.

  • Medical Knowledge
    10. An investigatory and analytic thinking approach to the clinical situation is demonstrated.
    11. Basic and clinically supportive sciences appropriate to their discipline are known and applied.

  • Practice Based Learning and Improvement
    13. Information about other populations of patients, especially the larger population from which this patient is drawn, is obtained and used.

  • Interpersonal and Communication Skills
    19. The health professional works effectively with others as a member or leader of a health care team or other professional group.

  • Systems Based Practice
    23. Differing types of medical practice and delivery systems including methods of controlling health care costs and allocating resources are known.
    24. Cost-effective health care and resource allocation that does not compromise quality of care is practiced.
    26. Partnering with health care managers and health care providers to assess, coordinate, and improve health care and how these activities can affect system performance are known.


    Donna M. D’Alessandro, MD
    Professor of Pediatrics, University of Iowa Children’s Hospital