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PubMedDate not supplied

Retinoid therapy of pigmentary disorders.

Topical retinoids such as all-trans-retinoic acid (RA), 13-cis-retinoic acid (isotretinoin), retinol, retinaldehyde, tazarotene, and adapalene have been shown to improve dyspigmentation of photodamaged skin including mottling and actinic lentigines. RA monotherapy has also been demonstrated to improve melasma and postinflammatory hypermelanosis. Furthermore, RA in combination with hydroquinone or 4-hydroxyanisole, or azelaic acid increases the potency of depigmenting agents for the treatment of melasma, actinic lentigines, and postinflammatory hypermelanosis. The basic mechanisms underlying these effects are not completely identified. Topical retinoids stimulate the cell turn-over of epidermal keratinocytes and promote a decrease in melanosome transfer and a rapid loss of melanins via epidermopoiesis. Topical retinoids are also involved in the control of cell differentiation. Retinoid-induced changes in the stratum corneum and the permeability barrier may also facilitate the penetration of depigmenting agents in the epidermis and increase their bioavailability, leading to increased depigmentation. In addition, several in vitro studies demonstrate that cis and trans-retinoic acid inhibit UV-B stimulated melanogenesis in term of tyrosinase activity and melanin synthesis. It is likely that topical retinoids modulate epidermal melanin count via a direct action on melanocytes and epidermal keratinocytes.

Humans↗
PubMed1964

7-HYDROXYCHLORPROMAZINE: POTENTIAL TOXIC DRUG METABOLITE IN PSYCHIATRIC PATIENTS.

7-Hydroxychlorpromazine was isolated from liver and urine of psychiatric patients treated with high dosages of chlorpromazine for long periods. These patients developed a purple pigmentation limited to areas of skin exposed to sunlight, as well as opacities of the cornea and lens. Large amounts of melanin were found only in the pigmented skin. It seems likely that a toxic compound is produced by the action of ultraviolet light on a 7-hydroxylated chlorpromazine derivative deposited in skin, cornea, and lens, and that this in turn leads to excessive melanin production and eye changes.

Body Fluids↗
PubMedDate not supplied

[Hypomelanosis of Ito. A possibly under-diagnosed heterogeneous neurocutaneous syndrome].

INTRODUCTION: Hypomelanosis of Ito (HI) or incontinentia pigmenti achromians is a multisystemic neurocutaneous disorder that is associated to neurological complications in a high percentage of patients. AIMS: The purpose of this study is to review the most significant features in a series of 14 patients with HI. PATIENTS AND METHODS: We conducted a retrospective study in which the following data were analysed: age, sex, familial and personal history, clinical features and complementary explorations that were carried out. We report the cases of nine females and five males aged between 4 months and 14 years. RESULTS: All the patients presented neurological anomalies, including psychomotor or mental retardation in 11 (associated to autistic behaviour in two of them), neuroradiological anomalies in seven, microcephalus in three and epileptic seizures in two. Other significant complications were musculoskeletal and ocular anomalies (each of which were present in nine patients), dental disorders in six, coarse facies and dysmorphic ears in four patients, hypoacusis in five and congenital heart disease in two. The following were also observed, but as isolated events: choanal atresia, cleft palate, segmental dilatation of the colon, cryptorchidism, inguinal hernia, low height, vesicoureteral reflux and premature pubarche. CONCLUSIONS: There is no biological marker that identifies HI and a number of clinical forms only appear in the skin in a very mild form, which means they sometimes going unnoticed or are not considered to be important enough to establish a diagnosis. This entity may, therefore, be more frequent than we think and its prevalence is perhaps underestimated.

Abnormalities, Multiple↗
PubMed2005

Corrective cosmetics are effective for women with facial pigmentary disorders.

Visible facial lesions are a common and burdensome skin problem. This study examines the impact of corrective cosmetics in women with severe facial pigmentary disorders. Enrollment consisted of 73 women with one or more of the following conditions: acne, dermatosis papulosis, hypopigmentation, lentigines, melasma, rosacea, vascular proliferations, or other facial scars. The corrective cosmetic (Dermablend) was applied at the initial visit, at which time instructions and a supply of product were provided. Assessments were conducted at baseline, 2-week, 4-week, and 3-month follow-up visits on 63 patients using the Skindex-16. The corrective cosmetic was well tolerated. There was improvement in Skindex-16 scores after application of the corrective cosmetic, which continued at each follow-up visit and after adjustment for baseline confounders using multiple regression analyses. At 3 months, there was a 30% improvement in Skindex-16 score (P < .001). The corrective cosmetic was well tolerated and represents a valuable option that dermatologists can offer to patients with these conditions.

Adult↗
PubMed1987

Lethal genes surviving by mosaicism: a possible explanation for sporadic birth defects involving the skin.

A genetic concept is advanced to explain the origin of several sporadic syndromes characterized by a mosaic distribution of skin defects. It is postulated that these disorders are due to the action of a lethal gene surviving by mosaicism. The presence of the mutation in the zygote will lead to death of the embryo at an early stage of development. Cells bearing the mutation can survive only in a mosaic state, in close proximity with normal cells. The mosaic may arise either from a gametic half chromatid mutation or from an early somatic mutation. This concept of origin is proposed to apply to the Schimmelpenning-Feuerstein-Mims syndrome, the McCune-Albright syndrome, the Klippel-Trenaunay syndrome, the Sturge-Weber syndrome, and neurocutaneous melanosis. Moreover, this etiologic hypothesis may apply to two other birth defects that have recently been delineated, the Proteus syndrome (partial gigantism of hands or feet, hemihypertrophy, macrocephaly, linear papillomatous epidermal nevus, subcutaneous hemangiomas and lipomas, accelerated growth, and visceral anomalies), and the Delleman-Oorthuys syndrome (orbital cyst, porencephaly, periorbital appendages, and focal aplasia of the skin.

Abnormalities, Multiple↗
PubMed2003

Identification of a locus for dyschromatosis symmetrica hereditaria at chromosome 1q11-1q21.

Dyschromatosis symmetrica hereditaria is a rare autosomal dominant cutaneous disorder characterized by a mixture of hyperpigmented and hypopigmented macules of various sizes on the face and the dorsal aspects of the extremities. The genetic basis for this disease is unknown. We performed a genome-wide search in two large Chinese families to map the chromosome location of the responsible gene. We identified a locus at chromosome 1q11-1q21 with a cumulative maximum two-point LOD score of 8.85 at marker D1S2343 (at recombination fraction=0.00). Haplotype analyses indicated that the disease gene is located within the 11.6 cM region between markers D1S2696 and D1S2635. This is the first locus identified for dyschromatosis symmetrica hereditaria. This study provides a map location for isolation of a disease gene causing dyschromatosis symmetrica hereditaria.

China↗
PubMed2003

Mild phenotype in a 15-year-old boy with Pallister-Killian syndrome.

Pallister-Killian syndrome is a rare disorder characterized by multiple congenital anomalies, coarse face, pigmentary skin changes, seizures, severe mental retardation, and the presence of an extra metacentric chromosome i(12p) confined to skin fibroblasts only. Here, we report on an unusual case of i(12p) in a 15-year-old boy presenting with mild mental retardation, minor facial features (long face, prognathism, short neck), normal weight, length, and OFC parameters as well as hyperpigmented streaks. The boy attended normal school until the age of 14 years. Because of hyperpigmented stripes, chromosome analysis was performed on skin fibroblasts. This study showed that 37% of the cells had an additional isochromosome for the short arm of chromosome 12. This observation illustrates the phenotypic variability of i(12p) and emphasizes the importance of skin fibroblasts chromosome analysis in patients with pigmentary skin changes.

Abnormalities, Multiple↗
PubMed1983

Suppression of cytotoxic effect of mitomycin-C by superoxide dismutase in Fanconi's anemia and dyskeratosis congenita fibroblasts.

Survival curves were determined for several human diploid fibroblast strains treated with mitomycin-C (MMC) with or without concomitant incubation with superoxide dismutase (SOD). These included cells from patients with Fanconi's anemia (FA), dyskeratosis congenita (DC) a disorder related to FA, Gardner's syndrome (GS) and xeroderma pigmentosum grop C (XPC). Incubation with SOD had no effect on MMC-induced cytotoxicity in the two normal cell strains, XPC or GS. Although GM2053 (FA) and two DC strains showed intermediate sensitivity to killing by MMC similar to XPC and GS, the survival of these cell strains was increased approximately 2-4 times after 0.5 microgram/ml of MMC by concomitant treatment with SOD. Survival of the most MMC sensitive cell strain GM1309 (FA) was sharply increased by adding SOD; survival was enhanced about 15-fold after treatment with 0.1 microgram/ml of MMC. SOD induced no enhancement of survival in MMC treated normal cells at survival levels down to nearly 10(-3). We propose that the hypersensitivity to MMC cytoxicity in FA and DC cells may involve among other factors a deficiency in the inactivation of certain free radical intermediates.

Adolescent↗
PubMed1990

Clinical and ultrastructural studies of Romberg's hemifacial atrophy.

Romberg's disease is an uncommon and poorly understood condition manifested by progressive hemifacial atrophy of skin, soft tissue, and bone. In order to better define the natural history and anatomic variation of this disorder, we evaluated 41 patients by history, physical examination, and facial radiographs. Light microscopic studies were performed on tissue from 19 patients, and ultrastructural analysis was performed on specimens from 6 patients. The average age at inception of the disease was 8.8 years. Atrophy, within one or more trigeminal nerve dermatomes, progressed at a variable rate (mean period of active tissue dissolution = 8.9 +/- 6 years). In 26 patients with skeletal involvement, the mean age of onset was 5.4 years, versus 15.4 years for 15 patients without skeletal involvement, a statistically significant difference (p less than 0.01). However, there was no correlation between the severity of soft-tissue deformity and the age of onset. Electron microscopy demonstrated lymphocytic infiltrates in neurovascular bundles and abnormalities of vascular endothelium and basement membranes. We hypothesize that the pathogenesis of Romberg's disease involves chronic cell-mediated vascular injury and incomplete endothelial regeneration along branches of the trigeminal nerve (lymphocytic neurovasculitis).

Adult↗
PubMed1988

Phototoxicity of chlorpromazine on retinal pigment epithelial cells.

As it is known that chlorpromazine (CPZ) can bind to melanins as well as cause ocular phototoxicity, we investigated the cytotoxic effects of UV-visible irradiation of melanotic and amelanotic retinal pigment epithelial (RPE) cells in the presence of CPZ. At low concentrations (5 micrograms/ml) of CPZ a photosensitization reaction took place which lysed the cells as measured by the release of 51Cr from cells labelled with chromium. At concentrations of CPZ less than 5 micrograms/ml, no significant cell lysis occurred when the cells were incubated at 37 degrees C in the dark. As the concentration of CPZ was increased to 25 micrograms/ml or more, high percentages of cells were lysed. When the melanotic RPE cells were exposed to different concentrations of CPZ and grown in culture, the cell growth (multiplication) diminished drastically with low concentrations (less than 2 micrograms/ml CPZ). Vitamin E decreased the cell lysis both in the dark and upon irradiation. Oxygen radical scavengers such as glutathione, B-carotene, mannitol, D-penicillamine as well as superoxide dismutase and catalase did not decrease cell lysis. The phototoxic effects of CPZ was found not to be due to stable photoproducts formed during irradiation of CPZ.

Animals↗
PubMed1994

Hypomelanosis of Ito associated with West syndrome: report of a case.

Hypomelanosis of Ito (HI) is a rare neurocutaneous disorder characterized by hypopigmented macules along the Blaschko line and multiple abnormalities, including seizures, developmental retardation, ophthalmologic defects, and chromosome mosaicism. We report a four-month-old female baby with typical skin lesions on the right upper limb, chest, and scalp, noted at the age of one week. She also had a seizure disorder which manifested as neck flexion and hand gripping with series formation from the age of three months. Electroencephalogram (EEG) demonstrated modified hypsarrhythmia. The characteristic clinical and electroencephalographic features favored the diagnosis of West syndrome. Magnetic resonance imaging revealed an absence of abnormal neuronal migration. The auditory brainstem evoked response, nerve conduction velocity, and ophthalmologic examinations were all within normal limits. The seizure responded to adrenocorticotropic hormone therapy on the 12th day of initial therapy, and the EEG became normal. However, another different pattern of seizures characterized by staring and lateral gaze in a right upward direction occurred two weeks later. Carbamazepine and phenobarbital were added to the therapeutic regimen. She was regularly followed up at the outpatient department every two weeks after one-and-a-half months of hospitalization. Infantile spasms with evidence of hypsarrhythmias in the EEG recurred at seven months of age. Oral steroid therapy reduced seizure frequency by 80%. As far as we know, this is the first case report of HI combined with infantile spasms in Taiwan.

Female↗
PubMed1997

Skewed X-inactivation in carriers of X-linked dyskeratosis congenita.

A gene causing Dyskeratosis Congenita (DC), a rare genetic disorder associated with bone marrow failure, has been mapped to chromosome Xq28, but autosomal inheritance of the disease has also been reported. We have investigated the pattern of X-inactivation in the peripheral blood of carriers of DC using the methylation-sensitive Hpa II site in the androgen receptor gene (HUMARA). In 5 different families in which the inheritance of DC appears to be X-linked, all 16 carriers showed skewed X-inactivation patterns. These cases indicate that, in the hematopoiesis of heterozygous females, cells expressing the normal DC allele have a growth advantage over cells that express the mutant allele. In 7 other families with sporadic cases of DC or with an uncertain pattern of inheritance, both skewed and normal patterns of X-inactivation were observed. In these families or where crucial family members are unavailable, the study of X-inactivation patterns will add to linkage analysis in providing information about carrier status.

Chromosome Mapping↗
PubMed1999

Koraxitrachitic syndrome: a syndromic form of self-healing collodion baby with residual dappled atrophy of the derma.

We report on a child with a generalized skin disorder associated with other minor anomalies. At birth, the child presented as a collodion baby, with patchy erythema, generalized irregular dermal atrophy, alopecia, absent eyelashes and eyebrows, and conjunctival pannus. He also had hypertelorism, prominent nasal root, large mouth, micrognathia, brachydactyly, syndactyly involving all interdigital spaces, and camptodactyly of fingers III-V. The hyperkeratotic membrane thinned progressively, leaving a mottled reticulated skin atrophy, with patchy areas of yellowish hyperpigmentation and papyraceous areas. Hair and nails were dystrophic. Mental development was borderline normal. The histological hallmarks of the skin manifestations combined orthokeratotic hyperkeratosis and marked atrophy of the dermis. The dermal extracellular matrix was immature, and factor XIII-a positive dendrocytes were rare and globular rather than dendritic. We frame as a hypothesis that the disease is due to or associated with a defect in maturation of a subset of dermal dendrocytes during fetal life. This entity may be designed as the koraxitrachitic syndrome (kappaomicronrhoalphaxi:grapnel- taurhoalphachiiotatauepsilonsigma: roughness)

Abnormalities, Multiple↗
PubMed2000

Myelocystocele-cloacal exstrophy in a pedigree with a mitochondrial 12S rRNA mutation, aminoglycoside-induced deafness, pigmentary disturbances, and spinal anomalies.

A large Filipino-American family with progressive matrilineal hearing loss, premature graying, depigmented patches, and digital anomalies was ascertained through a survey of a spina bifida clinic for neural crest disorders. Deafness followed a matrilineal pattern of inheritance and was associated with the A1555G mutation in the 12S rRNA gene (MTRNR1) in affected individuals as well as unaffected maternal relatives. Several other malformations were found in carriers of the mutation. The proband had a myelocystocele, Arnold-Chiari type I malformation, cloacal exstrophy, and severe early-onset hearing loss. Several family members had premature graying, white forelock, congenital leukoderma with or without telecanthus, somewhat suggestive of a Waardenburg syndrome variant. In addition to the patient with myelocystocele, two individuals had scoliosis and one had segmentation defects of spinal vertebrae. The syndromic characteristics reported here are novel for the mitochondrial A1555G substitution, and may result from dysfunction of mitochondrial genes during early development. However, the mitochondrial A1555G mutation is only rarely associated with neural tube defects as it was not found in a screen of 218 additional individuals with spina bifida, four of whom had congenital hearing loss.

Aminoglycosides↗
PubMed2004

PET imaging of implanted human retinal pigment epithelial cells in the MPTP-induced primate model of Parkinson's disease.

Human retinal pigment epithelial (hRPE) cells produce L-dopa, are easily harvested and expanded in culture, and, attached to microcarriers, can survive in the brain without immunosuppression. Studies in rats, primates, and parkinsonian patients have demonstrated that striatally implanted hRPE cells attached to gelatin microcarriers (RPE-GM) are able to improve parkinsonian symptoms and are well tolerated for extended periods. In moderately to severely impaired monkeys with bilateral 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine hydrochloride (MPTP)-induced parkinsonism receiving a unilateral RPE-GM implant in the putamen, there was a 39% improvement in clinical scores over the first 2 months post-implant. Positron emission tomography (PET) with [18F]fluoro-L-dopa (FDOPA) showed increased accumulation in the implanted putamen and a concomitant decrease in [11C]raclopride binding in the same area, suggesting increased dopamine release compared to the contralateral putamen. We report the first in vivo visualization of hRPE cells and their effects, implicating a dopaminergic mechanism of action.

Animals↗
PubMed1997

Dyschromatosis.

The dyschromatoses are a group of disorders characterized by the presence of both hyperpigmented and hypopigmented macules, many of which are small in size and irregular in shape. There are two major forms-dyschromatosis symmetrica hereditaria (DSH) and dyschromatosis universalis hereditaria (DUH), both of which are seen most commonly in Japan. DSH was first described by Toyama in 1929 and is characterized by a symmetrical distribution of hyperpigmented and hypopigmented macules on the extremities, especially over the dorsa of the hands and feet. In 1933, Ichikawa and Hiraga were the first to describe DUH as well-demarcated brown macules admixed with various-sized hypopigmented macules in a generalized as opposed to acral distribution. DUH was noted to appear within the first month of life. Some clinicians have suggested that DSH might be a subtype of DUH; however, we have to wait for the cloning of the causal genes of these diseases before coming to any definite conclusions. The differential diagnosis of dyschromatosis includes xeroderma pigmentosum, dyschromic amyloidosis, and exposure to chemicals such as diphenylcyclopropenone and monobenzyl ether of hydroquinone.

Age Factors↗
PubMed1986

Assignment of the gene for dyskeratosis congenita to Xq28.

Dyskeratosis congenita is an X-linked recessive disorder with diagnostic dermatological features, bone marrow hypofunction, and a predisposition to neoplasia in early adult life. Linkage analysis was undertaken in an extensive family with the condition using the Xg blood group and 17 cloned X chromosomal DNA sequences which recognise restriction fragment length polymorphisms (RFLPs). No recombination was observed between the locus for dyskeratosis congenita (DKC) and the RFLPs identified by DXS52 (St14-1) (Zmax = 3.33 at theta max = 0 with 95% confidence limits of 0 to 14cM). Similarly no recombination was observed for the disease locus and F8 (Zmax = 1.23 at theta max = 0) nor for DXS15 (Zmax = 1.62 at theta max = 0), but both of these markers were only informative in part of the family whereas DXS52 was fully informative. DXS52, DXS15, and F8 are known to be tightly linked and have previously been assigned to Xq28. Thus the gene for dyskeratosis congenita can be assigned to Xq28. These DNA sequence polymorphisms will be of clinical value for carrier detection and prenatal diagnosis.

Adolescent↗
PubMed2002

Disappearance of pili annulati following an episode of alopecia areata.

Pili annulati is a distinctive autosomal dominant hair shaft disorder that produces alternating light and dark bands that can give a spangled appearance to the hair. The literature contains three case reports of patients in whom the condition has disappeared following recovery from alopecia totalis. None of these reports contain a direct microscopic comparison of pre- and post-regrowth hairs. We report a 6-year-old girl who was first noted to have pili annulati at the age of 2 years and who developed alopecia totalis at the age of 3 years. When the hair regrew spontaneously, 18 months later, the pili annulati was no longer visible. Hair samples obtained before and after the episode of alopecia areata were compared by normal and cross-polarized light microscopy. While not apparent on careful clinical examination, banding was present on light microscopy in 20% of the hairs. Eighty per cent of the affected hairs displayed banding throughout their entire length. In contrast, prior to the episode of alopecia totalis, when the pili annulati was clearly visible, 50% of the hair obtained was banded on microscopy and 90% of the affected hairs showed banding throughout their microscopic length.

Alopecia Areata↗