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eMedicine Journal > Pediatrics > Nutrition
Malnutrition

Synonyms, Key Words, and Related Terms: protein-energy malnutrition, PEM, protein-calorie malnutrition, kwashiorkor, marasmus, starvation, hunger, poor diet, nutritional deficiency
Author Information | Introduction | Clinical | Workup | Treatment | Follow-up | Test Questions | Bibliography

AUTHOR INFORMATION Section 1 of 8    Click here to go to the top of this page Click here to go to the next section in this topic

Authored by Donna G Grigsby, MD, Associate Professor, Department of Pediatrics, University of Kentucky College of Medicine

Coauthored by Harohalli R Shashidhar, Associate Professor, Department of Pediatrics, Chief, Division of Pediatric Gastroenterology and Nutrition, University of Kentucky Medical Center

Donna G Grigsby, MD, is a member of the following medical societies: Ambulatory Pediatric Association, American Academy of Pediatrics, and Kentucky Pediatric Society

Edited by Maria Rebello Mascarenhas, MBBS, Associate Professor of Pediatrics, University of Pennsylvania School of Medicine; Section Chief, Division of Gastroenterology and Nutrition, Director, Nutrition Support Service, Children's Hospital of Philadelphia; Mary L Windle, PharmD, Adjunct Assistant Professor, University of Nebraska Medical Center College of Pharmacy, Pharmacy Editor, eMedicine.com, Inc; Jatinder Bhatia, MD, Professor of Pediatrics, Chief, Section of Neonatology, Vice Chairman for Clinical Research, Department of Pediatrics, Medical College of Georgia; Merrily P M Poth, MD, Professor, Department of Pediatrics and Neuroscience, Uniformed Services University of the Health Sciences; and Jatinder Bhatia, MD, Professor of Pediatrics, Chief, Section of Neonatology, Vice Chairman for Clinical Research, Department of Pediatrics, Medical College of Georgia

Author's Email:Donna G Grigsby, MDClick here to view conflict-of-interest information on the author of this topic
Editor's Email:Maria Rebello Mascarenhas, MBBS 

eMedicine Journal, June 30 2006, VOLUME 7, Number 6
INTRODUCTION Section 2 of 8   Click here to go to the next section in this topic Click here to go to the top of this page Click here to go to the next section in this topic

Background: The World Health Organization defines malnutrition as "the cellular imbalance between supply of nutrients and energy and the body's demand for them to ensure growth, maintenance, and specific functions." Malnutrition is globally the most important risk factor for illness and death, contributing to more than half of deaths in children worldwide. Protein-energy malnutrition (PEM), first described in the 1920s, is observed most frequently in developing countries but has been described with increasing frequency in hospitalized and chronically ill children in the United States.

Kwashiorkor and marasmus are 2 forms of PEM that have been described. The distinction between the 2 forms of PEM is based on the presence (kwashiorkor) or absence (marasmus) of edema. Marasmus involves inadequate intake of protein and calories, whereas a child with kwashiorkor has fair-to-normal calorie intake with inadequate protein intake. Although significant clinical differences between kwashiorkor and marasmus exist, some studies suggest that marasmus represents an adaptation to starvation whereas kwashiorkor represents a dysadaptation to starvation.

In addition to PEM, children may be affected by micronutrient deficiencies, which also have a detrimental effect on growth and development. The most common and clinically significant micronutrient deficiencies in children and childbearing women throughout the world include deficiencies of iron, iodine, zinc, and vitamin A and are estimated to affect as many as two billion people. Although fortification programs have helped diminish deficiencies of iodine and vitamin A in individuals in the United States, these deficiencies remain a significant cause of morbidity in developing countries, while deficiencies of vitamin C, B, and D have improved in recent years. Micronutrient deficiencies and protein and calorie deficiencies must be addressed for optimal growth and development to be attained in these individuals.

Pathophysiology: Malnutrition affects virtually every organ system. Dietary protein is needed to provide amino acids for synthesis of body proteins and other compounds that have a variety of functional roles. Energy is essential for all biochemical and physiologic functions in the body. Furthermore, micronutrients are essential in many metabolic functions in the body as components and cofactors in enzymatic processes.

In addition to the impairment of physical growth and of cognitive and other physiologic functions, immune response changes occur early in the course of significant malnutrition in a child. These immune response changes correlate with poor outcomes and mimic the changes observed in children with acquired immune deficiency syndrome (AIDS). Loss of delayed hypersensitivity, fewer T lymphocytes, impaired lymphocyte response, impaired phagocytosis secondary to decreased complement and certain cytokines, and decreased secretory immunoglobulin A (IgA) are some changes that may occur. These immune changes predispose children to severe and chronic infections, most commonly, infectious diarrhea, which further compromises nutrition causing anorexia, decreased nutrient absorption, increased metabolic needs, and direct nutrient losses.

Early studies of malnourished children showed changes in the developing brain, including, a slowed rate of growth of the brain, lower brain weight, thinner cerebral cortex, decreased number of neurons, insufficient myelinization, and changes in the dendritic spines. More recently, neuroimaging studies have found severe alterations in the dendritic spine apparatus of cortical neurons in infants with severe protein-calorie malnutrition. These changes are similar to those described in patients with mental retardation of different causes. There have not been definite studies to show that these changes are causal rather than coincidental.

Other pathologic changes include fatty degeneration of the liver and heart, atrophy of the small bowel, and decreased intravascular volume leading to secondary hyperaldosteronism.

Frequency:

Mortality/Morbidity: Malnutrition is directly responsible for 300,000 deaths per year in children younger than 5 years in developing countries and contributes indirectly to over half the deaths in childhood worldwide.

Age:

CLINICAL Section 3 of 8   Click here to go to the next section in this topic Click here to go to the top of this page Click here to go to the next section in this topic

History:

Physical: Physical findings that are associated with PEM include the following:

Causes:

WORKUP Section 4 of 8   Click here to go to the next section in this topic Click here to go to the top of this page Click here to go to the next section in this topic

Lab Studies:

Other Tests:

TREATMENT Section 5 of 8   Click here to go to the next section in this topic Click here to go to the top of this page Click here to go to the next section in this topic

Medical Care:

Consultations:

Diet:

FOLLOW-UP Section 6 of 8   Click here to go to the next section in this topic Click here to go to the top of this page Click here to go to the next section in this topic

Further Outpatient Care:

Deterrence/Prevention:

Prognosis:

TEST QUESTIONS Section 7 of 8   Click here to go to the next section in this topic Click here to go to the top of this page Click here to go to the next section in this topic

CME Question 1: A 15-month-old boy presents to a clinic with poor growth and anasarca. His mother reports a decrease in activity and listlessness over the last week. His past medical history is significant for multiple allergies, including several foods for which he has been placed on a restricted diet consisting of rice water and a few vegetables. His mother reports no diarrhea or change in stools or urine output. On physical examination, irritability, wasting muscle mass, and diffuse edema are observed. Which of the following is the most likely etiology of this infant’s kwashiorkor?


A: Inadequate ingestion of protein
B: Protein malabsorption
C: Acute nephrotic syndrome
D: Protein-losing enteropathy
E: Protein allergy

The correct answer is A: This child is ingesting very little protein with his diet of rice water and vegetables. Malabsorption or enteropathy is unlikely with normal stools. Although normal urine output does not rule out nephrotic syndrome completely, he has wasting, which is unusual for acute nephrosis.

CME Question 2: The immunologic changes observed in children with malnutrition most closely resemble those changes found in which of the following disease processes?


A: B-cell deficiency
B: Agammaglobulinemia
C: Acquired immune deficiency syndrome (AIDS)
D: Isolated T-cell deficiency
E: Immunoglobulin subclass deficiency

The correct answer is C: The immune changes observed in children with malnutrition correlate with poor outcomes and mimic the changes observed in children with acquired immune deficiency syndrome (AIDS). They include loss of delayed hypersensitivity, fewer T lymphocytes, impaired lymphocyte response, impaired phagocytosis secondary to decreased complement and certain cytokines, and decreased secretory immunoglobulin A (IgA).

Pearl Question 1 (T/F): In addition to the impairment of physical growth and of cognitive and other physiologic functions, immune response changes occur early in the course of significant malnutrition in a child.

The correct answer is True: These immune response changes correlate with poor outcomes and mimic the changes observed in children with acquired immune deficiency syndrome (AIDS).

Pearl Question 2 (T/F): Common micronutrient deficiencies include iron, zinc, and vitamin A deficiencies.

The correct answer is True: The most common and clinically significant micronutrient deficiencies in children and childbearing women throughout the world include deficiencies of iron, iodine, zinc, and vitamin A and are estimated to affect as many as 2 billion people. Although fortification programs have helped diminish deficiencies of iodine and vitamin A in individuals in the United States, these deficiencies remain a significant cause of morbidity in developing countries, while deficiencies of vitamin C, B, and D have improved in recent years.

Pearl Question 3 (T/F): Childhood malignancies are associated with nutritional deficiencies in children.

The correct answer is True: Cystic fibrosis, chronic renal failure, childhood malignancies, neuromuscular diseases, congenital heart disease, and multiple food allergies are the most common chronic illnesses associated with nutritional deficiencies in children.

Pearl Question 4 (T/F): In the United States, children who have acute illness are at highest risk for malnutrition.

The correct answer is False: Children with lower socioeconomic status (SES), in shelters for the homeless, and in rural areas are at highest risk for malnutrition. Hospitalized children and children with chronic illnesses also are at high risk for malnutrition.
BIBLIOGRAPHY Section 8 of 8   Click here to go to the next section in this topic Click here to go to the top of this page

NOTE:
Medicine is a constantly changing science and not all therapies are clearly established. New research changes drug and treatment therapies daily. The authors, editors, and publisher of this journal have used their best efforts to provide information that is up-to-date and accurate and is generally accepted within medical standards at the time of publication. However, as medical science is constantly changing and human error is always possible, the authors, editors, and publisher or any other party involved with the publication of this article do not warrant the information in this article is accurate or complete, nor are they responsible for omissions or errors in the article or for the results of using this information. The reader should confirm the information in this article from other sources prior to use. In particular, all drug doses, indications, and contraindications should be confirmed in the package insert. FULL DISCLAIMER
eMedicine Journal, June 30 2006, VOLUME 7, Number 6
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