Emaciation

Emaciation refers to severe loss of body mass and tissue, especially fat and skeletal muscle, resulting from a prolonged negative energy balance. It is marked by marked wasting and may accompany weakness and fatigue. Emaciation can arise from inadequate caloric intake, malabsorption, or increased metabolic demands, and may occur with acute illness or chronic disease. Clinically it denotes a pathological state rather than mere thinness.

Causes include malnutrition from famine or eating disorders, chronic diseases such as cancer, kidney or liver failure, HIV/AIDS, tuberculosis, and inflammatory or malabsorption conditions. Hypermetabolic states such as hyperthyroidism or sepsis can contribute. In cancer cachexia, inflammatory cytokines drive muscle proteolysis and lipolysis, promoting weight loss even with adequate intake. Refeeding syndrome can complicate recovery after prolonged starvation.

Presentation includes rapid or progressive weight loss, thin appearance with loss of subcutaneous fat and muscle, weakness, fatigue, anorexia, and reduced physical function. Laboratory findings may show hypoalbuminemia, anemia, electrolyte disturbances, and elevated inflammatory markers. Diagnosis relies on history, examination, and measurements of weight and body composition, with evaluation for underlying causes.

Management targets the underlying condition and nutritional rehabilitation. Strategies include controlled caloric and protein intake, oral supplements, and enteral or parenteral feeding as needed, with attention to refeeding risk. Multidisciplinary care and physical therapy help preserve lean mass and function. Prognosis depends on the cause, duration, and response to treatment, but persistent emaciation often signals serious morbidity.