U01.01.077 Protein-energy malnutrition

Protein-energy malnutrition (PEM) refers to a condition where the body does not get enough protein and energy (calories), leading to a range of clinical symptoms. The two primary forms of PEM are Kwashiorkor and Marasmus.

Kwashiorkor

Kwashiorkor is a form of malnutrition caused by severe protein deficiency despite adequate calorie intake. It primarily affects children and is associated with several clinical manifestations due to insufficient protein, particularly in the synthesis of proteins such as albumin.

Clinical Features:

Skin Lesions: Hyperkeratosis and dyspigmentation (patchy, discolored skin)
Edema: Caused by decreased plasma oncotic pressure
Liver Dysfunction: Fatty change due to reduced apolipoprotein synthesis
Abdominal Swelling: Due to edema, presenting as a swollen belly

Key Symptoms – MEALS:

M: Malnutrition
E: Edema
A: Anemia
L: Liver (fatty change)
S: Skin lesions (hyperkeratosis, dyspigmentation)

Feature	Kwashiorkor
Primary Deficiency	Protein
Edema	Present
Skin Lesions	Hyperkeratosis, dyspigmentation
Liver Changes	Fatty liver due to decreased apolipoproteins
Abdominal Distension	Present due to edema

Marasmus

Marasmus is another form of protein-energy malnutrition characterized by a calorie deficiency but with no significant protein deficiency. It is primarily associated with muscle wasting and fat loss.

Clinical Features:

Muscle Wasting: Loss of muscle mass due to the calorie deficiency
No Edema: Unlike Kwashiorkor, edema is not a feature of Marasmus
Overall Growth Failure: Stunted growth in children due to prolonged malnutrition

Feature	Marasmus
Primary Deficiency	Calories
Edema	Absent
Muscle Wasting	Present
Growth	Failure (stunted growth)

Points to Remember:

Kwashiorkor results from protein deficiency and presents with edema, skin lesions, and fatty liver.
Marasmus is caused by caloric deficiency leading to muscle wasting but no edema.
Both conditions are signs of severe malnutrition, but the key difference lies in the type of deficiency: protein in Kwashiorkor, and calories in Marasmus.

USMLE Step 1 Review Series

Curriculum

U01.01.077 Protein-energy malnutrition

Kwashiorkor

Clinical Features:

Key Symptoms – MEALS:

Marasmus

Clinical Features:

Points to Remember:

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