Failure to thrive (FTT) is a clinical state of growth failure due to any cause, characterized by any one or more of following features:
- Lack of growth i.e. weight < 3 percentile,
- Sustained weight loss
- Reduced growth velocity i.e. weight dropping at least two major percentiles below the previous values (e.g. from 75Lh to percentile).
Although weight is a defining criteria, other parameters of growth like height, are frequently affected.
Etiologically it may be due to non-organic or organic causes.
Non-organic is more common up to 80%, usually seen in under-5 children due to nutritional or emotional deprivation.
Organic Failure to thrive may develop at any age due to identifiable causes e.g. —
- Decreased food intake despite availability e.g. mechanical or neuro muscular problems in sucking, eating or swallowing,
- Impaired digestion/absorption of nutrients,
- Increased metabolic requirements e.g. chronic diseases or infections, and
- Increased losses of ingested food e.g. chronic diarrhea or vomiting.
Clinically these children present with —
- Malnutrition e.g. growth failure, anemia, vitamin and mineral deficiencies.
- Behavioral changes e.g. apathy, social withdrawal, poor eye contact response to cuddling.
- Developmental retardation
- Recurrent/persistent infections
- Signs of primary disease e.g. chronic infections, illnesses, emotional deprivation etc.
Diagnostic approach in Failure to thrive may be divided into three steps i.e. —
- preliminary clinical evaluation and investigations
- evaluation of response to the trial feeding and
- revaluation with more exhaustive investigations in cases, refractory to trial feeding.
Step 1: Preliminary evaluation which includes —
a) Detailed history, specially related to dietary intake, preceding infections like diarrhea etc., child abuse/ neglect and developmental history. Available case records like growth charts should be reviewed to estimate the age of onset for Failure to thrive.
b) Physical examination, specially related to anthropometric values and signs of malnutrition, vitamin/mineral deficiencies, systemic infections/ illnesses and abuse/neglect etc.
c) Baseline investigations to exclude common causes i.e.
- Complete hemogram for anemia, infections etc.
- Urine analysis for UTI, chronic renal disease etc.
- Stool analysis for malabsorption, worms etc.
- X-ray chest and Tuberculin test for TB.
- Skeletal survey to assess bone age.
Step 2: Trial feeding: Although many cases may be managed at home with nutritional counseling and periodic followup, hospitalization is indicated in cases with:
- Severe under nutrition with weight < 60%
- Suspected child abuse/neglect
- Suspected organic disease
- Doubtful dietary intake.
In hospital, all cases should receive trial feeding i.e. supervised, unlimited high caloric diet (150-200 call kg/day) for a minimum of 14 days, if necessary by nasogastric tube, along with daily weight record.
A weight gain of 50 gm/day from 45th day onward and sustained for at least a week is considered as satisfactory, suggestive of non-organic etiology. Absence of satisfactory weight gain on trial feeding indicates organic Failure to thrive.
Step 3: Re-valuation with detailed investigations is indicated in non-responsive cases to trial feeding and include —
- Biochemical investigations e.g. Blood sugar, Serum proteins, liver/renal function tests, screening tests for renal tubular acidosis/aminoaciduria.
- Endocrinal studies e.g. Thyroid function tests, growth hormone assays including somatomedin C levels, cortisol levels etc.
- Genetic studies for inborn errors of metabolism, including molecular studies and enzyme assays in selected cases.
Management of Failure to thrive targets not only to nutritional rehabilitation but also to resumption of appropriate emotional environment & treatment of the underlying organic cause. In most cases, A multi-disciplinary approach is required which includes —
- Nutritional therapy with increasing volume, frequency and caloric density of meals, avoidance of low-caloric foods and dietary supplementation.
- Psychological support and modification of home environment.
- Treatment of underlying cause & associated problems e.g. vitamin deficiencies, anemia etc. All children should be immunized to their age-appropriate level.
- Parental counseling regarding correct nutritional and hygienic practices.
- Periodic growth monitoring and regular follow-up after discharge, as Failure to thrive frequently recurs due to persistence of etiological factors.
Prognosis: Although initial catch-up growth is excellent in most of the adequately treated cases, it tends to slow down over time and recurrence of Failure to thrive is not uncommon. Long-standing Failure to thrive in early life may lead to persistent development problems like cognitive, behavioral and language disorders, as more than 90% of brain growth completes in infancy.