Chapter 072. Malnutrition and Nutritional Assessment (Part 2)

MarasmusThe end stage of cachexia, marasmus is a state in which virtually all available body fat stores have been exhausted due to starvation. Conditions that produce marasmus in developed countries tend to be chronic and indolent, such as cancer, chronic pulmonary disease, and anorexia nervosa.Marasmus is easy to detect because of the patients starved appearance. The diagnosis is based on severe fat and muscle wastage resulting from prolonged calorie deficiency. Diminished skin-fold thickness reflects the loss of fat reserves; reduced arm muscle circumference with temporal and interosseous muscle wastingreflects the catabolism of protein throughout the body, including vital organs...
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Chapter 072. Malnutrition and Nutritional Assessment (Part 2) Chapter 072. Malnutrition and Nutritional Assessment (Part 2) Marasmus The end stage of cachexia, marasmus is a state in which virtually allavailable body fat stores have been exhausted due to starvation. Conditions thatproduce marasmus in developed countries tend to be chronic and indolent, such ascancer, chronic pulmonary disease, and anorexia nervosa. Marasmus is easy to detect because of the patients starved appearance. Thediagnosis is based on severe fat and muscle wastage resulting from prolongedcalorie deficiency. Diminished skin-fold thickness reflects the loss of fat reserves;reduced arm muscle circumference with temporal and interosseous muscle wastingreflects the catabolism of protein throughout the body, including vital organs suchas the heart, liver, and kidneys. The laboratory findings in marasmus are relatively unremarkable. Thecreatinine-height index (the 24-h urinary creatinine excretion compared withnormal values based on height) is low, reflecting the loss of muscle mass. Occasionally, the serum albumin level is reduced, but it stays above 2.8g/dL in uncomplicated cases. Despite a morbid appearance, immunocompetence,wound healing, and the ability to handle short-term stress are reasonably wellpreserved in most patients with marasmus. Marasmus is a chronic, fairly well-adapted form of starvation rather than anacute illness; it should be treated cautiously, in an attempt to reverse thedownward trend gradually. Although nutritional support is necessary, overly aggressive repletion canresult in severe, even life-threatening metabolic imbalances such ashypophosphatemia and cardiorespiratory failure. When possible, oral or enteralnutritional support is preferred; treatment started slowly allows readaptation ofmetabolic and intestinal functions (Chap. 73). Kwashiorkor In contrast to marasmus, kwashiorkor in developed countries occurs mainlyin connection with acute, life-threatening illnesses such as trauma and sepsis, andchronic illnesses that involve acute-phase inflammatory responses. The physiologic stress produced by these illnesses increases protein andenergy requirements at a time when intake is often limited. A classic scenario forkwashiorkor is the acutely stressed patient who receives only 5% dextrosesolutions for periods as brief as 2 weeks. Although the etiologic mechanisms are not clear, the protein-sparingresponse normally seen in starvation is blocked by the stressed state and bycarbohydrate infusion. In its early stages, the physical findings of kwashiorkor are few and subtle.Fat reserves and muscle mass are initially unaffected, giving the deceptiveappearance of adequate nutrition. Signs that support the diagnosis of kwashiorkor include easy hairpluckability, edema, skin breakdown, and poor wound healing. The major sine quanon is severe reduction of levels of serum proteins such as albumin ( Cellular immune function is depressed, reflected by lymphopenia (complications. It is important to determine the major component of PEM so thatthe appropriate nutritional plan can be developed. If kwashiorkor predominates,the need for vigorous nutritional therapy is urgent; if marasmus predominates,feeding should be more cautious.