Elevated plasma homocysteine levels in patients on isotretinoin therapy for cystic acne.

BACKGROUND: The use of Isotretinoin (Iso) for cystic acne (CA) therapy includes marked side-effects such as dyslipidemia, increased liver enzymes, and reduction of biotinidase activity. Moreover, Homocysteine (Hcy), an amino acid, is metabolized in the liver requiring folate, vitamin B6, vitamin B12, and the activity of enzymes, i.e. cystathionine-beta-synthase. Increased blood levels of Hcy are associated with premature occlusive vascular disease. OBJECTIVE: The aim of this study was the evaluation of Hcy levels and the responsible vitamins for its metabolism in patients with CA on Iso treatment. METHODS AND RESULTS: Twenty-eight patients with CA were submitted to laboratory examinations before (Value 1) and after (Value 2) 45 days on Iso (0.5 mg/kg/24 h) therapy. Blood levels of Hcy and vitamin B6 were evaluated by HPLC methods, and folate and vitamin B12 using a commercial Kit. Hcy levels (Value 1 = 7.86 +/- 1.6 micromol/L; Value 2 = 13.65 +/- 3.3 micromol/L; P < 0.001) were statistically significantly increased in patients on treatment. Vitamins were unaltered, and lipids and liver enzymes increased. Significant correlation between Hcy levels, vitamins, and liver enzymes was found. Methionine loading tests performed in nine patient-volunteers showed an abnormal response post-treatment. CONCLUSIONS: It is suggested that the elevated Hcy levels in patients after 45 days on Iso therapy could be due either to the 'inhibition' of cystathionine-beta-synthase by the drug and/or their liver dysfunction. Daily vitamin supplementation along with frequent evaluations of Hcy blood levels are recommended for the prevention of a premature occlusive vascular disease.

L-carnitine supplementation in patients with cystic acne on isotretinoin therapy.

BACKGROUND: Patients with cystic acne (CA) on Isotretinoin (Iso) therapy might present muscular symptoms as side effect of the drug. Myalgia, weakness, hypotension are also some of the main characteristics of carnitine (car) deficiency. METHODS: Two hundred and thirty (N = 230) patients with CA were treated with Isotretinoin (0.5 mg/kg per 24 h). All the patients were requested to visit our out-patient department at the onset of muscular symptoms. Laboratory tests including car (total, free, acylcarnitine) were determined in blood and urine before treatment, at the onset of muscular symptoms and after the end of a 45 day study. Fifty percent of the patients with muscular involvement received L-carnitine (100 mg/kg per 24 h per os) (group C) and 50% placebo (group P). RESULTS: Their laboratory tests showed the well known increases of their liver enzymes and lipids, whereas car blood levels were remarkably decreased at the onset of their muscular symptoms and or at the end of the study. Their supplementation with L-car, in patients of group C (N = 20) without Iso discontinuation or reduction, resulted in the disappearance of their muscular symptoms within 5-6 days and normalisation not only of the increased levels of their liver enzymes but also those of car, at the 45 day of their therapy. Additionally, the patients who received placebo (group P, N = 20) continued complaining for mualgias. The rest of the patients (group A, N = 190) did not experience any muscular symptoms, their laboratory tests showed elevation of liver enzymes and lipids and a decrease in car levels in the blood whereas a remarkable increase of car excretion was determined in their urine. CONCLUSIONS: Iso therapy decreases car blood levels in patients with CA. L-car supplementation might treat liver and muscular side effects of the drug. These hopeful preliminary results need further investigation.

Vitiligo therapy with oral and topical phenylalanine with UVA exposure.

The administration of phenylalanine (Phe) combined with UVA exposure was found to be effective in treating vitiligo. Twenty-one patients with vitiligo were divided in two groups: eleven patients were treated with oral L-Phe in a dose of 100 mg/kg body weight and with UVA exposure and ten patients were treated with oral L-Phe in a dose of 100 mg/kg body weight and with UVA exposure. In addition, in the second group, a cream containing 10% L-Phe was applied to the vitiliginous areas. The best results occurred in the second group. No side effects were found in either group.