bubble_chart Overview

Malnutrition in a broad sense should include both undernutrition or deficiency and overnutrition. Currently, only the former is discussed. Malnutrition often occurs secondary to certain medical and surgical causes, such as chronic diarrhea, short bowel syndrome, and malabsorptive diseases. Non-medical causes of malnutrition include poverty and food shortages, lack of nutritional knowledge, and parents neglecting scientific feeding methods. In developed countries, malnourished patients can usually be treated by addressing the primary disease, providing appropriate diets, educating parents, and careful follow-up. However, in many third-world countries, malnutrition is a major cause of child mortality. There is a complex interplay between malnutrition, social habits, environment, and acute and chronic infections, making treatment very difficult and not simply a matter of providing adequate food.

bubble_chart Clinical Manifestations

There are two typical symptoms. Marasmus, caused by severe caloric deficiency, results in stunted growth, emaciation, loss of subcutaneous fat, loss of skin elasticity, dry and easily falling hair, and general weakness and lethargy. The other type is Kwashiorkor, caused by severe protein deficiency, characterized by generalized edema, particularly in the eyelids and dependent parts of the body, dry and atrophic skin, hyperkeratosis and desquamation, or pigmentation, brittle and easily breaking hair, fragile nails with transverse grooves, loss of appetite, hepatomegaly, and often diarrhea with watery stools. There is also a mixed type, which falls between the two, and all types may be accompanied by signs of other nutrient deficiencies.

bubble_chart Diagnosis

1. Medical History: It is essential to understand the child's dietary intake, eating habits, and conduct a dietary survey to assess the intake of protein and calories. Determine if there are any conditions affecting digestion, absorption, or chronic wasting diseases. Additionally, understand the general family situation, the growth patterns of family members, the height and weight of the parents, and their level of concern for the child.

2. Clinical Symptoms: There are typically two classic symptoms. The first is Marasmus, caused by severe calorie deficiency, characterized by stunted growth, emaciation, loss of subcutaneous fat, loss of skin elasticity, dry and easily falling hair, weakness, and lethargy. The second is Kwashiorkor, caused by severe protein deficiency, presenting with generalized edema, eyelid and dependent body part edema, dry and atrophic skin, keratosis and desquamation, or pigmentation, brittle and easily breaking and falling hair, brittle nails with transverse grooves, loss of appetite, hepatomegaly, frequent diarrhea, and watery stools. There is also a mixed type, intermediate between the two, and all may be accompanied by manifestations of other nutrient deficiencies.

3. Physical Measurements: Physical measurements are the most reliable indicators for assessing malnutrition. Currently, there are significant changes in the international standards for evaluating malnutrition, which include three parts.

(1) Underweight: A child's weight-for-age compared to the standard reference population of the same age and sex, below the median minus 2 standard deviations but above or equal to the median minus 3 standard deviations, is classified as grade II underweight. If below the median minus 3 standard deviations of the reference population, it is classified as grade III underweight. This indicator reflects past and/or current chronic and/or acute malnutrition but cannot distinguish between acute and chronic malnutrition solely based on this indicator.

(2) Stunting: A child's height-for-age compared to the standard reference population of the same age and sex, below the median minus 2 standard deviations but above or equal to the median minus 3 standard deviations, is classified as grade II stunting. If below the median minus 3 standard deviations of the reference population, it is classified as grade III stunting. This indicator mainly reflects past or long-term chronic malnutrition.

(3) Wasting: A child's weight-for-height compared to the standard reference population of the same age and sex, below the median minus 2 standard deviations but above or equal to the median minus 3 standard deviations, is classified as grade II wasting. If below the median minus 3 standard deviations of the reference population, it is classified as grade III wasting. This indicator reflects recent acute malnutrition in children.

bubble_chart Treatment Measures

1. Treatment during the emergency phase

(1) Anti-infection The relationship between malnutrition and infection is inseparable. The most common infections are gastrointestinal, respiratory, and/or skin infections, and sepsis is also common. Appropriate antibiotic treatment is required.

(2) Correction of typical edema and electrolyte imbalance In the emergency treatment of malnutrition, the management of dehydration and electrolyte imbalance is particularly important, especially in children with diarrhea accompanied by malnutrition. The following points should be noted:

① Pay attention to the fluid intake to prevent heart failure.

② Adjust and maintain electrolyte balance: Malnourished children often have severe potassium deficiency. When urine output is normal, potassium can be given at 6-8mmol/(kg·d) for at least 5 days. There are also deficiencies in calcium, magnesium, zinc, and phosphorus, which should be treated if deficient. When high-energy, hypertonic parenteral nutrition is given, the condition may worsen further. Generally, magnesium is supplemented at 2-3mmol/(kg·d), zinc at 1-2mmol/(kg·d), calcium at the usual dose, and sodium in small amounts to avoid heart failure, approximately 3-5mmol/(kg·d).

(3) Nutritional support After correcting fluid and electrolyte imbalances, the treatment of malnutrition depends on the degree of intestinal absorption function damage. If intestinal absorption is poor, central venous nutrition or peripheral venous nutrition can be used as needed. The former has a longer retention time and a higher concentration of nutrient solution, while the latter should not exceed 5 days. The composition and amount of parenteral nutrition should be based on maintaining the child's fluid needs, generally 100ml/(kg·d). Protein is generally 2g/(kg·d). Fat is the main source of energy, providing 60% of the total energy. When using parenteral nutrition, serum glucose should be monitored every 6 hours to prevent hyperglycemia. Liver function should be followed up weekly.

2. Treatment of complications

(1) Hypoglycemia Especially common in marasmus, generally 10ml of 50% glucose can be injected intravenously after blood sampling upon admission, followed by 5-10% glucose solution in the fluid replacement.

(2) Hypothermia In severe marasmus with hypothermia, the mortality rate is high, mainly due to insufficient energy. Pay attention to the ambient temperature (30-33℃), and use hot water bags or other methods to keep warm (beware of burns) while monitoring body temperature, every 15 minutes if necessary.

(3) Anemia Severe anemia with Hb <40g/L may require blood transfusion, generally 10-20ml/kg for marasmus. Edematous type generally does not require transfusion unless anemia leads to collapse or heart failure. Mild and grade II anemia can be treated with iron, 2-3mg/(kg·d), for 3 months.

3. Treatment during the stage of convalescence

(1) Providing sufficient energy and protein is extremely important. When calculating energy and protein needs, the average weight for the corresponding age (or P50) should be used, not the child's actual weight. The energy and protein requirements per kilogram of body weight are shown in Table 3-1, multiplied by the ideal weight to get the daily intake.

(2) Food selection Choose foods suitable for the child's digestive ability and nutritional needs, preferably high-protein and high-energy foods such as dairy products and animal proteins like eggs, fish, meat, poultry, and soy products, as well as fresh vegetables and fruits.

Table 3-1 Energy and protein requirements

Age (months)	kcal/kg	Protein g/kg
0-6	115	2.2
6～12	105	2.0
12～36	100	1.8
48～72	85	1.5

*Excerpted from: Gellis CS and Kagan BM: Current Pediatric Therapy 13.

（3）Functions to promote digestion and improve metabolism

①Drug therapy: Administer various digestive enzymes such as pepsin and pancreatic enzymes to aid digestion. Appropriate use of anabolic steroids like nandrolone phenylpropionate, intramuscular injection of 10～25mg each time, 1～2 times per week, for 2～3 weeks, can promote protein synthesis in the body and increase appetite. However, sufficient calories and protein should be supplied during medication.

4. Disease cause treatment

Treat primary diseases such as chronic digestive system diseases and wasting diseases like subcutaneous node and heart, liver, and kidney diseases. Educate parents on scientific feeding knowledge, encourage breastfeeding, appropriately add complementary foods, and wean in a timely manner. Change poor dietary habits such as picky eating and partiality.

bubble_chart Complications

(1) Hypoglycemia

(2) Hypothermia

(3) Anemia