title: Evaluation of the relative dose response test for vitamin A nutriture in cirrhotics.
abstract: The rise in serum vitamin A 5 h after a 450 microgram oral dose of the vitamin (retinyl palmitate) was used to assess vitamin A nutriture in patients with alcoholic cirrhosis. The test was carried out on 21 hospitalized male patients and 12 normal age and sex-matched control subjects. The relative dose response (RDR), expressed as percentage, was calculated as A5 - A0/A5 X 100 where A0 = the fasting serum retinol level and A5 = the serum retinol 5 h postdosing. Vitamin A-deficient patients (those with serum retinol levels less than 30 microgram/dl and an abnormal dark adaptation test or RDR greater than or equal to 14%) were treated with 4 wk of oral vitamin A (10,000 microgram/day), then repeat RDR and dark adaptation tests were carried out. Among eight cirrhotics with abnormal dark adaptation, the mean +/- SEM RDR was 21 +/- 9 versus 3 +/- 3% in patients with normal dark adaptation (p less than 0.01). RDR tests of patients with normal dark adaptation did not differ from those of 12 normal age and sex-matched control subjects (normal RDR response 0 to 14%). Among patients found to be vitamin A-deficient, treatment with vitamin A resulted in the mean +/- SEM RDR declining from 21 +/- 9 to 5 +/- 2%. However, this fall failed to reach statistical significance (p = 0.06). The RDR test appears to be useful as a predictor of vitamin A deficiency, even among patients with far advanced hepatic disease.
mesh_terms: D003623:Dark Adaptation; D004224:Diterpenes; D004305:Dose-Response Relationship, Drug; D006801:Humans; D008104:Liver Cirrhosis, Alcoholic / Q000150:complications*; D010168:Palmitates; D011517:Prothrombin Time; D000084562:Retinyl Esters; D014801:Vitamin A / Q000031:analogs & derivatives* / Q000097:blood; D014802:Vitamin A Deficiency / Q000175:diagnosis* / Q000209:etiology; D015032:Zinc / Q000097:blood
chemical_list: D004224:Diterpenes; D010168:Palmitates; D000084562:Retinyl Esters; D014801:Vitamin A; C014794:retinol palmitate; D015032:Zinc