Malnutrition

A state of nutrition in which a deficiency, excess or imbalance of energy, protein and other nutrients causes measurable adverse effects on tissue, body form, function and clinical outcome

Investigations

Albumin

• Synthesis reduced when supply of amino acids is limited

• Affected by many other factors, especially acute phase proteins

• Non-specific marker of illness

Transferrin

• Synthesis reduced in protein restriction

• Affected by acute phase proteins, iron deficiency and liver disease

Transthyretin (prealbumin)

• Reflects recent dietary intake (rather than overall nutritional status)

• Increased in uraemia and dehydration

• Decreased by acute phase proteins and fasting

Retinol binding protein

• Reflects recent dietary intake (rather than overall nutritional status)

• Affected more by energy

• Levels increased by increased GFR and alcoholism

• Levels decreased by chronic liver disorders, vitamin A deficiency and zinc deficiency

Urinary creatinine

• If renal function normal, excretion rate reflects muscle mass

IGF1

• Reduced in acute and chronic malnutrition and increases with repletion

• Levels reduced in liver disease and renal failure

• Less affected by acute phase proteins

• Serial measurements to monitor response more useful than use for single measurement to assess status

Management

Enteral tube feeding

• Indicated if inadequate/unsafe oral intake and a functional, accessible GI tract e.g. unconscious patient

Parental nutrition

• The administration of nutrient solutions via a central or peripheral vein

• Life-threatening complications

• Expensive

Complications

Refeeding syndrome

• Potentially fatal shift in fluids and electrolytes, and disturbances in organ function and metabolic regulation, that may result from rapid initiation of re-feeding after a period of undernutrition