Which of the following diseases is caused by Protein Energy Malnutrition (PEM) ?

Protein-Energy Malnutrition (PEM) is a nutritional disorder caused by an inadequate intake of dietary protein and/or total calories (energy) over a sustained period. In its classic clinical classification, two forms are recognised: marasmus, resulting from a severe, combined deficiency of both protein and energy intake and causing extreme wasting, and kwashiorkor, associated with a relative protein deficiency and presenting with nutritional oedema.

Among the four diseases listed, only Marasmus fits this profile: it develops in infants and young children from chronic, severe deprivation of protein and total caloric intake, producing marked loss of muscle and subcutaneous fat, growth failure, and a wasted, aged appearance, generally without edema. This makes Marasmus the disease caused by Protein Energy Malnutrition among the given options.

Why the other options do not fit:

• Scurvy is a deficiency disease of vitamin C (ascorbic acid), which is essential for collagen synthesis; its deficiency causes bleeding gums, joint pain, and poor wound healing — unrelated to protein-energy intake.

• Rickets is a deficiency disease of vitamin D (and associated calcium/phosphate metabolism), which is essential for bone mineralization; its deficiency causes soft, weak, and deformed bones in growing children.

• Beri-Beri is a deficiency disease of vitamin B1 (thiamine), which is essential for carbohydrate metabolism and nerve function; its deficiency causes nerve damage (dry beriberi) or heart failure and swelling (wet beriberi).

Cross-checking against this classification confirms that scurvy, rickets, and beri-beri are each linked to a single micronutrient (vitamin) deficiency, while marasmus alone is defined by combined protein-and-energy deficiency — confirming Marasmus as the correct answer.