Poor weight gain in children younger than two years in resource-abundant settings: Management

INTRODUCTION — Poor weight gain, also called "weight faltering," "faltering growth," or "growth deficit," refers to failure to gain weight appropriately; in more severe cases, linear growth and head circumference also may be affected. Although the term "failure to thrive" has been used for poor weight gain, we avoid it because it is ambiguous [1]. Poor weight gain is a sign that describes a particular problem rather than a diagnosis. The underlying cause of poor weight gain is "always insufficient usable nutrition," although a wide variety of medical and psychosocial stressors can contribute (table 1) [2].

The management of poor weight gain in infants and children younger than two years in resource-abundant settings will be discussed here. The etiology and evaluation of poor weight gain in children younger than two years, as well as poor weight gain in children older than two years in resource-abundant settings and the evaluation and management of poor weight gain and undernutrition in children from resource-limited settings are discussed separately.

●Resource-abundant settings:

•(See "Poor weight gain in children younger than two years in resource-abundant settings: Etiology and evaluation".)

•(See "Poor weight gain in children older than two years in resource-abundant settings".)

●Resource-limited settings:

•(See "Malnutrition in children in resource-limited settings: Clinical assessment".)

•(See "Management of moderate acute malnutrition in children in resource-limited settings".)

•(See "Management of uncomplicated severe acute malnutrition in children in resource-limited settings".)

•(See "Management of complicated severe acute malnutrition in children in resource-limited settings".)

DEFINITIONS — A consensus definition for poor weight gain is lacking. We define poor weight gain as weight less than the 2^nd percentile for gestation-corrected age and sex when plotted on an appropriate growth chart (figure 1A-B) (calculator 1) and decreased velocity of weight gain that is disproportionate to growth in length (figure 2A-B) (calculator 2) [3]. Weight below the 2^nd percentile is approximately equivalent to a Z-score of -2; the Z-scores is a value that represent the number of standard deviations from the mean value. (See "Measurement of growth in children", section on 'Weight'.)

Other definitions for poor weight gain are discussed separately. (See "Poor weight gain in children younger than two years in resource-abundant settings: Etiology and evaluation", section on 'Poor weight gain'.)

SEVERITY ASSESSMENT — One or more of the following parameters are used to define the severity of malnutrition in routine clinical practice (table 2) [4]:

●Weight-for-length Z-score (calculator 2)

●Mid-upper arm circumference (MUAC) or Z-score

●Decline in weight-for-length Z-score (calculator 2)

INDICATIONS FOR HOSPITALIZATION — Indications for hospitalization include [5-7]:

●Severe malnutrition (table 2) or body mass index ≤12 kg/m² (see "Poor weight gain in children younger than two years in resource-abundant settings: Etiology and evaluation", section on 'Severity of malnutrition')

●Significant dehydration (table 3)

●Serious intercurrent illness or significant medical problems

●Psychosocial circumstances that put the child at risk for harm

●Failure to respond to several months of outpatient management

●Precise documentation of energy intake

●Extreme parent or caregiver impairment or anxiety

●Extremely problematic caregiver-child interaction

●Practicality of distance, transportation, or family psychosocial problems preclude outpatient management

For children who do not meet the above criteria and are not otherwise seriously ill or at risk of harm, hospitalization may be neither helpful nor necessary unless the child is severely malnourished, seriously ill, or at risk of harm. Separation of the child from the family by hospitalization may promote anxiety and anorexia in the child and cause a delay in feeding and supporting the child within his their established environment. Contrary to previous teaching, weight gain during hospitalization does not conclusively prove that psychosocial factors are the sole cause of poor growth, nor does failure to gain weight conclusively exclude the role of psychosocial factors [8].

Having one or more underlying chronic conditions is an important predictor of the need for hospitalization. In a large retrospective cohort study of hospitalization for poor weight gain, approximately 41 percent of hospitalized children had a complex chronic condition and 15 percent had ≥2 chronic conditions [9]. Five percent of children were readmitted for poor weight gain within 30 days and 14 percent within three years. Readmission was associated with older age at admission, lower median household income, and prematurity-related chronic medical conditions.

INITIAL MANAGEMENT — Management of children with poor weight gain is individualized according to severity and chronicity of undernutrition, underlying medical disorders, and the needs of the child and family [7]. Successful management requires a plan to address contributing nutritional, medical, developmental/behavioral, and psychosocial factors [6]. Support of the caregivers is critical. They should be involved as much as possible in the formulation of the treatment plan [5,10]. The involvement of a dietitian, occupational or speech therapist, social worker, and/or developmental and behavioral pediatrician can be helpful in formulating a management plan.

Overview of approach — The pace and aggressiveness of initial management depends on the severity of malnutrition and underlying medical problems.

Mild malnutrition — Children with mild malnutrition (table 2) without an underlying medical disorder generally can be managed by the primary care clinician in the outpatient setting. For children with underlying medical conditions (eg, small for gestational age infant, fetal alcohol syndrome, prematurity, etc), multidisciplinary management may be warranted [7,11]. (See "Poor weight gain in children younger than two years in resource-abundant settings: Etiology and evaluation", section on 'Severity of malnutrition' and 'Adjunctive interventions' below and 'Interdisciplinary team' below.)

Depending on the contributing factors identified during the evaluation, management may include:

●Dietary counseling provided by the primary care clinician or a pediatric dietitian, focusing on ways to increase oral intake and change the feeding environment (table 4) [11,12]. (See 'Strategies to increase intake' below and 'Feeding environment' below.)

●Home-based support (eg, visiting nurse or other appropriately trained home visitor) [13-15]. (See 'Psychosocial support' below.)

●Referral to community, state, or federal assistance programs (eg, food pantries, food stamps, Supplemental Nutrition for Women, Infants, and Children [WIC] in the United States). (See 'Psychosocial support' below.)

●Regular follow-up visits to reinforce the feeding plan and monitor weight gain. (See 'Follow-up' below.)

In randomized trials, such simple interventions often are successful for children with mild malnutrition [13,14,16].

Moderate malnutrition — For children with moderate malnutrition (table 2), we suggest (see "Poor weight gain in children younger than two years in resource-abundant settings: Etiology and evaluation", section on 'Severity of malnutrition'):

●Interdisciplinary management in the outpatient setting [7,17,18].

The interdisciplinary team may be part of a specialized program at a referral center or, if such a program is not available, assembled by the primary care provider. (See 'Interdisciplinary team' below.)

●Involvement of a dietitian to formulate the nutrition plan and strategies to increase intake.

For children with moderate malnutrition, the target energy and protein intake should be achieved over 7 to 10 days to avoid complications associated with rapid refeeding [19]. (See 'Nutritional therapy' below and 'Prevention of nutritional recovery syndrome' below.)

●Provision of adjunctive interventions to address developmental and behavioral issues and provide psychosocial support as necessary. (See 'Adjunctive interventions' below.)

●Regular follow-up visits to reinforce the feeding plan and monitor weight gain. (See 'Follow-up' below.)

Severe malnutrition

●Hospitalization – For children with severe malnutrition (table 2) or body mass index <12 kg/m², we suggest hospitalization for initial management by an interdisciplinary team [7]. Hospitalization permits safe implementation of a feeding regimen that will ensure catch-up growth. Hospitalization also may permit recurrent opportunities for education of the caregivers about appropriate diet and feeding styles [5]. Hospital volunteers, when available, may provide valuable role modeling, support, and aid in feeding. (See "Poor weight gain in children younger than two years in resource-abundant settings: Etiology and evaluation", section on 'Severity of malnutrition'.)

●Feeding – Although we prefer to initiate feeding orally for most children with poor weight gain, we generally initiate feeds via a nasogastric tube for children with body mass index <12 kg/m². Nasogastric tube feeds also may be necessary for children who cannot or will not feed orally.

For children with severe malnutrition, the target energy and protein intake should be achieved over 7 to 10 days, with feedings every two to four hours [19,20]. (See 'Estimation of energy requirements' below.)

Gradual refeeding is necessary for several reasons:

•Severe malnutrition is almost always accompanied by anorexia [21]; during early refeeding, frequent small volume feeding may be better tolerated (see "Malnutrition in children in resource-limited settings: Clinical assessment", section on 'Kwashiorkor (edematous malnutrition)')

•Feedings with increased caloric density are usually hyperosmolar and can cause diarrhea and/or malabsorption if advanced too quickly [19,21,22]

•Refeeding may be complicated by a nutritional recovery syndrome ("refeeding syndrome") (see 'Prevention of nutritional recovery syndrome' below)

●Monitoring – During hospitalization, the child's daily food consumption is recorded, daily energy intake estimated, and daily weight gain monitored. Although there is no standardized approach, we monitor potassium and phosphate daily for the first three to five days of refeeding; the frequency thereafter is determined by the trend and response to supplementation (if necessary).

●Involvement of caregivers – The approach to feeding should be the same as the anticipated treatment at home after discharge. The caregivers should be involved as much as possible in the formulation of the treatment plan [5,10]. Caregivers of children with growth failure often feel a sense of failure that may be exacerbated by the success of the hospital staff in feeding the child and achieving weight gain.

●Discharge planning – Criteria for discharge include a safe home environment and demonstration by the caregivers that they understand and can carry out the management plan [19]. Weight gain is not necessary before discharge. Discharge planning should include provision of necessary support and follow-up [5]. (See 'Psychosocial support' below.)

●Follow-up – After discharge, children with severe malnutrition should continue to be followed by an interdisciplinary team. (See 'Follow-up' below.)

Interdisciplinary team — Most children with poor weight gain benefit from interdisciplinary management and/or home visiting programs [5,13,17,23-26]. In addition to the pediatric clinician, the interdisciplinary team may include dietitians, occupational or speech therapists, social workers, nurses, developmental specialists, child-life workers, psychiatrists, and workers from social and educational services in the community [5,27]. The health care provider and multidisciplinary team should work with the strengths of the family to encourage the development of a nurturing environment and to determine which of the potential interventions are most feasible and acceptable [11].

Nutritional therapy — Nutritional therapy is the mainstay of management of poor weight gain. The goal of nutritional therapy is to enable "catch-up" weight gain to overcome the weight deficit. Catch-up weight gain typically is two to three times the expected weight gain for age (table 5), or approximately 45 to 60 grams per day.

Consultation with a dietitian is helpful in assessing the severity of undernutrition, estimating energy intake and requirements for catch-up growth, and helping the caregivers plan menus tailored to the child's preferences that will provide enough dietary energy and nutrients for catch-up growth.

Estimation of energy requirements — Children with poor weight gain require a diet high in energy and other nutrients for catch-up growth [7,27]. The target energy intake is calculated from the estimated energy requirement (EER) for healthy children, plus additional energy for catch-up growth:

●Determine the EER – The EER describes the energy needs for children who are not undernourished [28-30]:

•0 through 2 months – 100 to 110 kcal/kg per day

•3 through 5 months – 85 to 95 kcal/kg per day

•6 through 8 months – 80 to 85 kcal/kg per day

•9 through 11 months – 80 kcal/kg per day

•12 through 24 months – 80 to 83 kcal/kg per day

●Target energy intake to permit catch-up growth – To estimate the daily energy requirement for catch-up growth, we usually multiply the EER for age by the median weight for the child's current length and divide by the child's actual weight [7,31,32]. As an example, in a 15-month-old male whose weight is 9 kg and length is 78 cm, the median weight for length is 10.4 kg (figure 3) and estimated energy intake for catch-up growth is 96 kcal/kg per day ([83 kcal/kg per day × 10.4 kg] ÷ 9 kg).

This estimate provides an appropriate initial target for energy intake, which is then adjusted depending on the growth response.

●Monitoring – The sufficiency of intake is proven by subsequent weight and, eventually, height gain [27]. Infants with severe malnutrition may require >200 kcal/kg for catch-up growth [33]. (See "Measurement of growth in children", section on 'Recommended growth charts with calculators'.)

Vitamin and mineral supplementation — During the catch-up growth phase, existing stores of vitamins and minerals may not be sufficient. We recommend a multivitamin preparation that includes iron and zinc for children who are being treated for poor weight gain [7,34,35]. The need for iron supplementation beyond the amount provided in a standard multivitamin is determined by laboratory evaluation. If the multivitamin does not contain zinc, zinc supplements should be provided (0.3 mg/kg of elemental zinc per day; maximum daily dose 6 mg). (See "Iron deficiency in infants and children <12 years: Screening, prevention, clinical manifestations, and diagnosis" and "Zinc deficiency and supplementation in children", section on 'Recommended intake'.)

Strategies to increase intake — Strategies to achieve adequate intake of energy and protein intake depend on the age and dietary preferences of the child. Consultation with a dietitian may help the caregivers plan menus tailored to the child's preferences that will provide enough dietary energy and nutrients for catch-up growth.

●Young infants – The feeding schedule for infants depends on the infant's nutritional needs and hunger cues. Infants younger than four months require frequent feedings, typically 8 to 12 per day; infants older than four months typically require between four and six feedings per day. Strategies to increase the caloric density of human milk and infant formula are provided below.

•Human milk – In the inpatient setting, the caloric density of human milk is generally increased with human milk fortifiers. In the outpatient setting, the caloric density of human milk for term infants can be increased by adding infant formula powder to pumped breast milk [36].

-For breast milk with 22 kcal per ounce (30 mL), add one-half teaspoon (2.5 mL) of infant formula powder to 3 ounces (89 mL) of pumped breast milk.

-For breast milk with 24 kcal per ounce (30 mL), add one teaspoon (5 mL) of regular formula powder to 3 ounces (90 mL) of pumped breast milk.

The caloric density of human milk should not be increased by the addition of carbohydrate (eg, maltodextrin) or fat (eg, medium chain triglyceride) because the protein concentrate of such a mixture is inadequate for optimum growth [36].

The fortification of human milk for premature infants is discussed separately. (See "Human milk feeding and fortification of human milk for premature infants", section on 'Fortification of human milk'.)

•Infant formula – The caloric density of infant formula can be increased by adding less water to powder or concentrated formula or by adding modular supplements such as glucose polymers (eg, maltodextrin) or fat (eg, medium chain triglycerides, corn oil) (table 6) [6].

Increasing the caloric density of commercial infant formula through concentration or the addition of glucose polymers and medium chain triglycerides increases the osmolality of the formula, which can cause diarrhea or malabsorption [22,35,36]. For this reason, formulas usually are not concentrated beyond 24 kcal per ounce (30 mL) unless fluid restriction is necessary (eg, for infants with congenital heart disease). Increases in the caloric density beyond 24 kcal/ounce (30 mL) should be made gradually (eg, in increments of 3 kcal per ounce [30 mL]) with modular supplements (glucose polymers, medium chain triglycerides) to a maximum of 30 kcal per ounce (30 mL).

The addition of carbohydrate or fat to standard infant formulas alters the nutrient ratio of the formula by providing nonprotein calories [36,37]. Providing more than 60 percent of energy from fat may induce ketosis and should be avoided. Consultation with a dietitian may be warranted to ensure an appropriate balance of macronutrients.

●Older infants and children

•Strategies to increase caloric density – For infants and young children who have started solid foods, energy intake can be increased by increasing the caloric density of foods that the child likes to eat (table 7) [6,11,38]; for example by:

-Adding rice cereal or formula powder to pureed foods

-Using high-calorie milk drinks instead of milk

-Adding cheese, butter, or sour cream to vegetables

During catch-up growth, total energy and protein intake is more important than variety.

•Meal and snack schedule – Older infants and children should eat often (every two to three hours, but not constantly):

-They should have three meals and three snacks on a consistent schedule.

-"Grazing" on low-nutrient snack foods throughout the day should be avoided.

-Snacks should be timed so that the child's appetite for meals will not be spoiled (eg, snack time should not occur within one hour of mealtime; snacks should be avoided immediately after an unfinished meal) [5].

At meal and snack time, solid foods should be offered before liquids [7].

•Beverages – Excessive fluid consumption reduces intake of solid foods. Constant sipping on low-calorie liquid, fruit juice, or carbonated drinks should be avoided. Juice consumption should be limited to 4 ounces (120 mL) per day of 100 percent fruit juice [39].

●Appetite stimulants – Appetite stimulants, such as cyproheptadine, may be helpful in selected circumstances but have no proven long-term benefit [40]. Limited data are available, and dosing regimens are varied. For children ≥2 years and adolescents who do not have adequate catch-up weight gain after three to six months of fortification of formula or food, some clinicians begin cyproheptadine at 0.25 mg/kg per day orally divided twice daily. Cyproheptadine is discontinued if weight gain is not improved after two to three months or if there are significant side effects, such as drowsiness. Cyproheptadine is discontinued if weight gain is not improved after two to three months or the caregivers complain of significant drowsiness.

Feeding environment — Changes to the feeding environment may help to ensure adequate energy intake for catch-up growth. It is helpful to meet with all caregivers to ensure that the feeding program is consistent.

General guidelines for optimizing the feeding environment include [6,11,35,38,41]:

●Infants should be positioned so that the head is up and the child is comfortable. Older infants and toddlers should sit upright in a highchair or on a booster seat at the table. Children should be allowed to feed themselves as is developmentally appropriate with caregivers gradually decreasing the amount offered through direct spoon-feeding as the child's self-feeding skills improve.

●Mealtime distractions should be minimized.

●Mealtime should be relaxed and social; eating with other family members and pleasant conversation not related to food should be encouraged.

●Mealtime should be free of battles over eating; caregivers should encourage, but not force, the child to eat; food should not be withheld as punishment.

●The child should be praised when they eat well but not punished when they do not.

Additional tips for caregivers are provided in the table (table 4).

Prevention of nutritional recovery syndrome — In severely malnourished children, refeeding may be complicated by a nutritional recovery syndrome ("refeeding syndrome"). Symptoms and signs occur within the first week of nutritional rehabilitation and include sweatiness, increased body temperature, hepatomegaly (caused by increased deposition in the liver), widening of the skull sutures (the brain growth is greater than the growth of the skull in infants with open sutures), increased periods of sleep, and fidgetiness or mild hyperactivity [6,20].

Rapid changes in tissue mineral content during the first week of refeeding may cause hypophosphatemia (which may cause skeletal abnormalities and exacerbate growth failure) and hypokalemia (which may cause muscle weakness, cardiac arrhythmias, and polyuria) [42]. Laboratory tests including potassium and phosphorus should be obtained for the first three to five days after initiation of refeeding to monitor for hypokalemia and hypophosphatemia. (See "Hypokalemia in children", section on 'Clinical manifestations'.)

Hypophosphatemia or hypokalemia can be treated orally with sodium phosphate or potassium phosphate in two divided doses to correct deficits. The estimated daily requirement for phosphorous approximates the dietary reference intake for age (ie, 100 mg per day [3.2 mmol per day] for infants 0 to 6 months, 275 mg per day for infants 6 to 12 months, and 460 mg per day for children 1 to 2 years [43]). Conversion from mg to mmol varies with the source of the supplement; consultation with a pharmacist is recommended. The estimated daily requirement for potassium is 1 to 2 mEq/kg. Phosphate and potassium supplements should be discontinued once serum levels have returned to normal.

Adjunctive interventions — General measures in the management of poor weight gain include interventions to address underlying medical, developmental, and behavioral factors contributing to undernutrition and anticipation and prevention of consequences of malnutrition [7].

Medical — Medical conditions that contribute to undernutrition should be addressed as indicated; as examples, referral to:

●An allergist for management of food allergies (see "Management of food allergy: Avoidance")

●A gastroenterologist for management of malabsorption or gastroesophageal reflux (see "Gastroesophageal reflux in infants" and "Management of gastroesophageal reflux disease in children and adolescents")

●Other specialists to manage inflammatory conditions that increase energy needs

Medical consequences of undernutrition should be anticipated and prevented as much as possible. As an example, children with undernutrition are at increased risk for recurrent infections; such infections should be treated promptly to prevent prolonged periods of decreased intake or increased losses associated with intercurrent illness. Immunizations should be administered according to the standard schedule and updated in children who have fallen behind. (See "Standard immunizations for children and adolescents: Overview", section on 'Routine schedule'.)

Developmental and behavioral — Developmental and behavioral problems may contribute to inadequate intake (eg, oral motor dysfunction) or increased losses (eg, rumination). Such problems must be addressed in the overall management plan. (See "Neonatal oral feeding difficulties due to sucking and swallowing disorders" and "Aspiration due to swallowing dysfunction in children" and "Poor weight gain in children younger than two years in resource-abundant settings: Etiology and evaluation", section on 'Development and behavior'.)

In the United States, early intervention programs may be helpful in addressing these problems by providing developmental stimulation and physical and occupational therapy as indicated. Referral to a developmental-behavioral pediatrician or behavioral psychologist may be helpful for such children.

Undernutrition in infancy is a risk factor for severe, irreversible developmental deficits and behavior problems [44]. The provision of early psychosocial stimulation may help to mitigate these problems [45,46]. In long-term follow-up of 129 children (9 to 24 months) with growth retardation who were randomly assigned to two years of nutritional supplementation with or without weekly psychosocial stimulation, early psychosocial stimulation was associated with increased adult intelligence quotient, higher educational attainment, and less involvement in violent behavior [45]. The developmental and behavioral status of children with poor weight gain during the first two years of life should be closely monitored and early childhood services provided as soon as possible when indicated. (See 'Prognosis' below and "Developmental-behavioral surveillance and screening in primary care".)

Psychosocial support — Psychosocial difficulties must be addressed in concert with improved nutrition. Effective treatment, whether in inpatient or outpatient setting, requires involvement and support of the caregivers.

Potential psychosocial interventions include:

●Home visitation by professional or appropriately trained lay personnel, which may be helpful in providing guidance, support, and monitoring [5,13,24,47,48]

●Facilitation of access to WIC, food stamps, and Temporary Assistance for Needy Families (formerly Aid to Families with Dependent Children) in the United States and similar programs in other countries; resources in the United States include [49]:

•2-1-1 – Provides information about school lunch programs, summer food programs, soup kitchens, community gardens, and government-sponsored food programs

•Feeding America – Provides a food bank locator and other resources for households without enough food

•MyPlate – Provides tip sheets and recipes for healthy eating at low cost

●Provision of additional guidance and support to caregivers (eg, housing advocacy, job training, substance abuse treatment, respite care)

Child neglect accounts for a minority of children with poor weight gain, but Child Protective Services should be involved if there is a history of intentional withholding of food from the child, strong beliefs in health and/or nutrition regimes that jeopardize a child's well-being, and/or a family that is resistant to recommended interventions despite a multidisciplinary team approach. (See "Child neglect: Evaluation and management", section on 'Notification of child protective services'.)

FOLLOW-UP

●Frequency of follow-up – Close follow-up and frequent contact with the health care team are essential for reinforcing nutritional recommendations and psychosocial support [50]. The frequency of follow-up depends on the child's age and severity of undernutrition but usually ranges from weekly to monthly [35]. Frequent follow-up should continue until catch-up growth is demonstrated and a positive trend is maintained [41]. Developmental and behavioral surveillance should occur at each of these visits and throughout childhood. (See "Developmental-behavioral surveillance and screening in primary care", section on 'Approach to surveillance'.)

Community social service workers, visiting nurses, and dietitians can facilitate monitoring between visits and help to ensure a nurturing environment [50]. (See 'Psychosocial support' above.)

●Indicators of response to management – Successful response to initial therapy is defined by achievement of catch-up growth (ie, a rate of weight gain that is two to three times the normal rate for age) (table 5). With adequate nutritional intake, catch-up growth is generally initiated within two days to two weeks, depending on the severity of the initial deficit [32,33,51].

Four to nine months of accelerated growth rates must be maintained to restore a child's weight for height [33]. As the deficits are replenished, intake and rates of growth spontaneously decelerate toward normal levels [33]. Catch-up growth in height/length lags several months behind that in weight but will occur if dietary treatment is continued appropriately [32,33].

●Discharge from follow-up – Guidelines for discharge from follow-up for poor weight gain are lacking. We extend the interval between visits when the child is consuming a normal diet for age and has demonstrated normal rate of weight gain for age and maintenance of weight-for-height above the 10^th percentile for age and sex on at least two assessments one month apart. However, we continue to monitor growth at approximately six-month intervals for at least one year to ensure that normal growth rates are maintained and that catch-up height has been achieved.

MANAGEMENT OF TREATMENT FAILURE — The management of treatment failure depends on previous interventions. For children with poor weight gain who have been followed by the primary care clinician for two to three months and have failed to achieve catch-up growth, outpatient management should be optimized. This may include involvement of, or referral to, a multidisciplinary team (if not already undertaken) [5,35].

Additional measures may include:

●Detailed nutritional assessment – Quantitative assessment of intake (eg, 24-hour food recall, three-day food record) may be helpful. (See "Dietary history and recommended dietary intake in children", section on 'Dietary diary'.)

●Assessment for additional contributing factors – For children followed by the primary care clinician or a multidisciplinary team who do not achieve catch-up growth despite adequate energy and protein intake for catch-up growth and improved or appropriate feeding technique, additional evaluation of medical, nutritional, and social factors is indicated [7,19,35]. This may include investigation for malabsorption, increased metabolic demands, or decreased ability to utilize nutrients (table 1) [7]. Assessment of feeding and feeding interventions by an occupational therapist may be needed to improve sucking, chewing, and/or swallowing. (See "Neonatal oral feeding difficulties due to sucking and swallowing disorders".)

●Enteral feeding – Supplementation of oral feedings with daytime or nighttime nasogastric feedings may be necessary in children who fail to achieve adequate catch-up growth despite four to six weeks of adequate oral intake [6]. Such children usually require the expertise of a multidisciplinary team.

•For children with mild or moderate malnutrition, nasogastric tube feedings may be initiated in the outpatient setting if adequate caregiver instructions for refeeding and periodic monitoring can be provided by home care personnel.

•For children with severe malnutrition, nasogastric tube feedings should be instituted in the hospital setting, where monitoring for the refeeding syndrome can be performed.

Nasogastric feedings can be discontinued after consistent weight gain has been demonstrated for four to six months.

If weight gain remains inadequate after three to four months of nasogastric tube feeding, gastrostomy tube placement may be appropriate. (See "Overview of enteral nutrition in infants and children".)

PROGNOSIS — The ultimate growth potential of a child with poor weight gain is determined by genetic potential, the timing of malnutrition (eg, intrauterine versus neonatal versus later infancy; poor weight gain with prenatal onset may be difficult to overcome, even with adequate postnatal nutrition), the severity of malnutrition, underlying medical problems, and whether underlying medical problems can be successfully managed [27,52].

Although the prognosis with respect to weight gain and growth is good, between 25 and 60 percent of infants with poor weight gain remain small for age (weight or height <20^th percentile for age and sex) beyond age two years [2,24,53-55].

Children with undernutrition are at risk for cognitive deficits [44]. Undernutrition has also been associated with behavior problems and learning problems [6,50]. Whether these findings are a direct result of undernutrition or the result of continued adverse social circumstances is not clear [53,56]. In either case, provision of psychosocial support and prompt initiation of early childhood services may be beneficial. (See 'Psychosocial support' above and 'Developmental and behavioral' above.)

SOCIETY GUIDELINE LINKS — Links to society and government-sponsored guidelines from selected countries and regions around the world are provided separately. (See "Society guideline links: Poor weight gain in infants and children".)

INFORMATION FOR PATIENTS — UpToDate offers two types of patient education materials, "The Basics" and "Beyond the Basics." The Basics patient education pieces are written in plain language, at the 5^th to 6^th grade reading level, and they answer the four or five key questions a patient might have about a given condition. These articles are best for patients who want a general overview and who prefer short, easy-to-read materials. Beyond the Basics patient education pieces are longer, more sophisticated, and more detailed. These articles are written at the 10^th to 12^th grade reading level and are best for patients who want in-depth information and are comfortable with some medical jargon.

Here are the patient education articles that are relevant to this topic. We encourage you to print or email these topics to your patients. (You can also locate patient education articles on a variety of subjects by searching on "patient education" and the keyword[s] of interest.)

●Basics topic (see "Patient education: Poor weight gain in babies and children (The Basics)")

●Beyond the Basics topic (see "Patient education: Poor weight gain in infants and children (Beyond the Basics)")

SUMMARY AND RECOMMENDATIONS

●Definition and severity – We define poor weight gain as weight less than the 2^nd percentile for gestation-corrected age and sex when plotted on an appropriate growth chart (figure 1A-B) (calculator 1) and decreased velocity of weight gain that is disproportionate to growth in length (figure 2A-B) (calculator 2). We classify the severity of malnutrition according to growth parameters (eg, weight-for-length, mid-upper arm circumference, decline in weight-for-length) (table 2). (See 'Severity assessment' above and 'Definitions' above.)

●Indications for hospitalization – Indications for hospitalization of children <2 years of age with poor weight gain include (see 'Indications for hospitalization' above):

•Severe malnutrition (table 2) or body mass index <12 kg/m²

•Significant dehydration (table 3)

•Serious intercurrent illness or significant medical problems

•Psychosocial circumstances that put the child at risk for harm

•Failure to respond to several months of outpatient management

•Precise documentation of energy intake

•Extreme parent or caregiver impairment or anxiety

•Extremely problematic caregiver-child interaction

•Practicality of distance, transportation, or family psychosocial problems preclude outpatient management

●Management – The management plan varies with severity and chronicity of undernutrition, underlying medical disorders, and the needs of the child and family. The involvement of a dietitian, occupational or speech therapist, social worker, and/or developmental and behavioral pediatrician can be helpful in formulating a management plan, particularly for children with moderate or severe malnutrition (table 2). (See 'Initial management' above and 'Interdisciplinary team' above.)

•Nutritional therapy is the mainstay of management. Catch-up growth requires energy intake greater than the estimated energy requirement (EER) for age. We estimate the daily energy requirement for catch-up growth by multiplying the average energy requirement for age by the median weight for the child's current length (figure 3) and dividing by the child's actual weight. (See 'Estimation of energy requirements' above.)

•We provide a multivitamin that includes iron and zinc during the catch-up phase of growth. (See 'Vitamin and mineral supplementation' above.)

•Strategies to achieve adequate intake vary with the age and dietary preferences of the child (table 6 and table 7). Changes to the feeding environment also may be necessary (table 4). (See 'Strategies to increase intake' above and 'Feeding environment' above.)

•We provide additional interventions as indicated for medical and developmental/behavioral conditions contributing to undernutrition and for prevention of medical, developmental, and behavioral consequences. Psychosocial support of the caregivers is critical. (See 'Adjunctive interventions' above.)

●Follow-up – The frequency of follow-up ranges from weekly to monthly, depending on severity. We continue frequent follow-up until the child demonstrates catch-up growth with maintenance of a positive trend. (See 'Follow-up' above.)

Response to therapy is defined by achievement of catch-up growth (ie, a rate of weight gain that is two to three times the normal rate for age) (table 5). With adequate nutritional intake, catch-up growth generally begins within two days to two weeks, depending on the severity of the initial deficit.

●Prognosis – Between 25 and 60 percent of infants with poor weight gain remain small for age (weight or height <20^th percentile for age and sex) beyond age two years. (See 'Prognosis' above.)

ACKNOWLEDGMENT — The UpToDate editorial staff acknowledges Rebecca Kirkland, MD, MPH, and Kathleen J Motil, MD, PhD, who contributed to earlier versions of this topic review.