Current developments of oral retinoid therapy with three generations of drugs. Non-aromatic, monoaromatic and polyaromatic retinoids (arotinoids)

Management of pediatric psoriasis with acitretin: A review

Psoriasis is a chronic inflammatory disease of the skin which can occur at any age-group. Psoriasis in childhood is not uncommon and has genetic susceptibility but usually, an environmental trigger such as infection is thought to initiate the disease process. Pediatric psoriasis has profound effects on both physical and psychosocial health of the patient. Treatment of mild psoriasis can be done with topical therapies but those which do not respond to topical therapies can be treated with phototherapy and systemic therapies. The use of systemic therapies in childhood is mainly based on the published data, case series, expert opinion and the experience as there is the lack of controlled trials in the age group. Based on the experience retinoids are probably the second line drugs for the treatment of pediatric psoriasis which do not respond to topical therapies and phototherapy. Using acitretin in a low dose and with proper physical examinations and laboratory investigations will reduce the hazard of potential serious adverse events. This article gives the review of the use of acitretin in pediatric psoriasis.

Retinoid augmentation of bioactive interleukin-1 production by murine keratinocytes

The effect of retinoids on the production of interleukin-1 (IL-1) by murine epidermal keratinocytes was investigated. Freshly isolated keratinocytes were cultured in the presence of etretinate, acitretin, all-trans retinoic acid or 13-cis retinoic acid at concentrations of 8 x 10(-9)-8 x 10(-6) mol/l. Exposure of keratinocytes to retinoids increased IL-1 bioactivity in culture supernatants and cell extracts at concentrations as low as 8 x 10(-9) mol/l, as assessed by T-cell proliferation. Prolongation of the culture period enhanced the augmentative effect of retinoids. All-trans retinoic acid and 13-cis retinoic acid had a greater ability to induce IL-1 production than the two aromatic retinoids, etretinate and acitretin. Treatment with 8-methoxypsoralen plus ultraviolet A radiation and treatment with triamcinolone acetonide both reduced the effect of retinoids on the production of bioactive IL-1.

A retrospective study of bone changes in adults treated with etretinate

Ninety patients aged 17 to 80 years were treated with etretinate for disorders of keratinization and were studied for bone changes. The treatment lasted from 0.1 to 7.9 years, mean 2.4 years. The average dosage of etretinate was 0.57 mg/kg/day (range 0.21 to 1.32 mg/kg/day), and the total dose was 31 gm (range 1 to 197 gm). Standard radiographs of the axial and peripheral skeleton were evaluated. The films of 44 patients showed skeletal abnormalities such as periosteal thickening, hyperostosis of the vertebral column, disk degeneration, osteoporosis, calcification of the spinal ligaments, and slender long bones. The present data indicate that the risk of skeletal disorders in adults treated with etretinate is significant (44 of 90), but that the severity of changes is minor.

Bone changes in children on long-term treatment with etretinate

Ten children with disorders of keratinization (ichthyosis, 4, pityriasis rubra pilaris, 2, psoriasis, 2, and palmoplantar keratoderma, 2) were treated with etretinate for 0.5 to 9.6 years. The children ranged from 1.5 to 15.7 years of age. The total dose of etretinate ranged from 700 to 52,596 mg and the maintenance dose, from 0.21 to 0.86 mg/kg/day. Radiographic skeletal surveys were performed at various stages during treatment or following treatment. Bone abnormalities were found in eight children. Six children had periosteal thickening, two periosteal bone resorption, two osteoporosis, three disc narrowing, and one slender long bones. Compared with age- and sex-matched normal controls, the children had decreased cortical bone thickness of the second left metacarpal bone. The children's physical growth and laboratory investigations were normal. We recommend that children on long-term etretinate therapy be investigated regularly for bone changes.

The effects of an aromatic retinoid (etretinate) on epidermal cell production and metabolism in normal and ichthyotic patients

Normal subjects and ichthyotic patients were biopsied before and after etretinate (Tigason) therapy. Histometric and cell kinetic measurements showed minimal changes following treatment. The metabolic activity across the epidermis was measured by a novel approach using the Quantimet 720 image analyser, and was significantly increased in the normal subjects as demonstrated by glucose-6-phosphate dehydrogenase (G6PDH), succinic dehydrogenase (SDH) and non-specific esterase (NSE) activities. In the ichthyotics studied the levels of G6PDH and SDH activity were significantly lowered following etretinate therapy, to levels similar to those demonstrated in normal subjects. In contrast, the activity of NSE was increased in the ichthyotics after etretinate therapy. It is suggested that the effect of retinoids is to 'normalize' the process of epidermal differentiation when it is abnormal.