ESSENTIAL FATTY-ACID DEFICIENCY IN PATIENTS RECEIVING HOME PARENTERAL-NUTRITION

Home parenteral nutrition (HPN), initiated in patients with severe mal absorption or decreased oral intake, may exhaust stores of essential f atty acids and cause clinical manifestations, mainly dermatitis. Plasm a fatty acid profiles were measured by gas-liquid chromatography in 37 healthy control subjects and 56 patients receiving HPN. The concentra tion (% by wt of total fatty acids) of 18:2n-6 was 22.8% and 11.4% (P < 0.001), whereas 18:3n-3 was 0.2% and 0.1% (P < 0.01) in control subj ects and patients, respectively. Reduced small bowel length was associ ated with aggravated biochemical signs of essential fatty acid deficie ncy (EFAD). The effect of parenteral lipid on plasma phospholipids was evaluated in subgroups of patients. In patients with > 200 cm of rema ining small intestine, those receiving parenteral lipids had only mino r changes in the fatty acids of plasma phospholipids compared with pat ients not receiving parenteral lipids. In patients with < 100 cm of re maining small intestine, those receiving parenteral lipids had increas ed concentrations of total n-6 fatty acids; however, these did not rea ch the concentrations in control subjects. No differences were seen in n-3 fatty acids. Twenty-five of the 56 patients receiving HPN reporte d skin problems. No differences were found in plasma phospholipid fatt y acids, Holman index, or the supply of parenteral lipids between pati ents with and without skin problems. Patients receiving HPN had bioche mical signs of EFAD. Parenteral lipids did not increase the concentrat ion of essential fatty acids to values comparable with those of contro l subjects, but 500 mt 20% Intralipid once a week was sufficient to pr event an increase in the Holman index above 0.2.