Final answer:
The diagnostic criteria for protein-energy malnutrition (PEM) include the presence of edema, severe muscle wasting, and weight loss, with kwashiorkor characterized by adequate calorie but insufficient protein intake, and marasmus by a severe deficiency in both protein and energy leading to significant muscle wasting and weight loss.
Step-by-step explanation:
Protein-energy malnutrition (PEM) is a condition characterized by inadequate consumption of protein and calories. It is seen in the form of two main diseases: kwashiorkor and marasmus. Kwashiorkor typically involves adequate energy intake but insufficient protein consumption and is identified by symptoms such as edema, a swollen abdomen, and changes in hair and skin. On the other hand, marasmus involves a severe deficiency in both energy and protein intake, leading to significant weight loss and muscle wasting. The earliest feature of protein deficiency can include indigestion and chronic diarrhea due to the inability to synthesize digestive enzymes. Liver dysfunction, as evidenced by a failure to synthesize plasma albumin, results in water retention and edema. Additionally, the skeletal muscles and red blood cells (RBC) can lose their integrity, leading to further wasting and anemia. Moreover, PEM in early childhood is indicated by stunted growth and failure to thrive.
For a clinical diagnosis, the absence of fat stores, visible severe wasting of muscle, and evidence of edema may be used as indicators for PEM. The condition is especially prevalent in less developed countries, where access to protein-rich foods may be limited.