Clinical patterns of pigmentary mosaicism - our experience (original) (raw)
Pigmentary mosaicism: a review of original literature and recommendations for future handling
Orphanet journal of rare diseases, 2018
Pigmentary mosaicism is a term that describes varied patterns of pigmentation in the skin caused by genetic heterogeneity of the skin cells. In a substantial number of cases, pigmentary mosaicism is observed alongside extracutaneous abnormalities typically involving the central nervous system and the musculoskeletal system. We have compiled information on previous cases of pigmentary mosaicism aiming to optimize the handling of patients with this condition. Our study is based on a database search in PubMed containing papers written in English, published between January 1985 and April 2017. The search yielded 174 relevant and original articles, detailing a total number of 651 patients. Forty-three percent of the patients exhibited hyperpigmentation, 50% exhibited hypopigmentation, and 7% exhibited a combination of hyperpigmentation and hypopigmentation. Fifty-six percent exhibited extracutaneous manifestations. The presence of extracutaneous manifestations in each subgroup varied: 32...
Pigmentary Mosaicism of Hyperpigmented Type in Two Sisters
Skinmed, 2005
Pigmentary mosaicism is a heterogeneous cutaneous phenotype that is often associated with extracutaneous anomalies. It is widely accepted that these phenotypes arise de novo as a result of a postzygotic mutation, leading to a mosaic status of the embryo. In the vast majority of cases, the occurrence of pigmentary mosaicism is sporadic. We report two paternal half-brothers affected with pigmentary mosaicism of the hyperpigmented type. The hyperpigmentation in both patients is distributed along the lines of Blaschko. In addition, mental retardation, facial asymmetry, short stature, scoliosis, and short fingers with clinodactyly of the 5th digit were noted in one of them. Chromosome analysis in this 15-year-old patient demonstrated a mosaic 46,XY,dup(3)(p21.3;pter)/46,XY with 12% aberrant cells in lymphocytes and 2% in skin fibroblasts derived from a hyperpigmented area. His nine-year-old half-brother had similar systematized hyperpigmented skin lesions, macrocephaly, facial asymmetry, and clinodactyly of the 5th digit. Chromosome analysis of peripheral lymphocytes showed a normal karyotype 46,XY. A skin biopsy could not be obtained. So far, some familial cases of hypopigmentation along the lines of Blaschko have been reported, but familial occurrence of the hyperpigmented type of pigmentary mosaicism appears to be extremely unusual. It is difficult to establish a causal relationship with the chromosomal mosaicism as observed in patient 1. Paradominant transmission seems unlikely because this would likewise imply that the chromosomal mosaicism is an incidental finding.
Pigmentary mosaicism of the hyperpigmented type in two half-brothers
American Journal of Medical Genetics, 2002
Pigmentary mosaicism is a heterogeneous cutaneous phenotype that is often associated with extracutaneous anomalies. It is widely accepted that these phenotypes arise de novo as a result of a postzygotic mutation, leading to a mosaic status of the embryo. In the vast majority of cases, the occurrence of pigmentary mosaicism is sporadic. We report two paternal half-brothers affected with pigmentary mosaicism of the hyperpigmented type. The hyperpigmentation in both patients is distributed along the lines of Blaschko. In addition, mental retardation, facial asymmetry, short stature, scoliosis, and short fingers with clinodactyly of the 5th digit were noted in one of them. Chromosome analysis in this 15-year-old patient demonstrated a mosaic 46,XY,dup(3)(p21.3;pter)/46,XY with 12% aberrant cells in lymphocytes and 2% in skin fibroblasts derived from a hyperpigmented area. His nine-year-old half-brother had similar systematized hyperpigmented skin lesions, macrocephaly, facial asymmetry, and clinodactyly of the 5th digit. Chromosome analysis of peripheral lymphocytes showed a normal karyotype 46,XY. A skin biopsy could not be obtained. So far, some familial cases of hypopigmentation along the lines of Blaschko have been reported, but familial occurrence of the hyperpigmented type of pigmentary mosaicism appears to be extremely unusual. It is difficult to establish a causal relationship with the chromosomal mosaicism as observed in patient 1. Paradominant transmission seems unlikely because this would likewise imply that the chromosomal mosaicism is an incidental finding.
Segmental Pigmentation Disorder: A Case Report of Hypopigmented Patch
Cureus
A segmental pigmentation disorder (SPD) is a form of pigmentary mosaicism. SPD is a hypo-or hyperpigmented patch that has a segmental pattern. A 16-year-old male with an insignificant past medical history presented with symptomless, slowly progressive skin lesions since early childhood. Skin examination revealed well-demarcated, non-scaling, hypopigmented patches on the right upper extremity. A similar spot was located on his right shoulder. Wood's lamp examination showed no enhancement. Differential diagnoses included segmental pigmentation disorder and segmental vitiligo (SV). A skin biopsy was obtained, which revealed normal findings. Based on the above clinicopathological findings, a diagnosis of segmental pigmentation disorder was made. The patient did not receive any treatment but was reassured that he did not have vitiligo.
Idiopathic eruptive macular pigmentation
International Journal of Dermatology, 2008
A 23-year-old, dark-skinned man presented at the dermatology department with pigmented macules over the trunk and proximal thighs of 2 months’ duration. He reported that the number of lesions had increased progressively for a few weeks and then remained stable. Skin examination showed oval brown macules and patches, 5–40 mm in diameter, involving mainly the anterior trunk and proximal thigh, but also the neck and dorsum (Fig. 1). The lesions were asymptomatic. There was no previous history of an inflammatory process, erythema, scaling, or drug intake. The mucous membranes, palms, and soles were clear. The pigmentation was not influenced by sunlight. Darier's sign (urticaria or erythema around the macules after scratching or rubbing of the lesions) was absent. The previous use of emollients, keratolytics, and topical antifungal agents did not alter the aspect of the lesions. The results of physical examination and routine laboratory tests (blood cell count, blood chemistry) were normal. Venereal Disease Research Laboratory (VDRL) test and direct skin examination and culture for fungus were negative. A biopsy specimen was obtained from a pigmented macule. The histologic study showed hyperkeratosis and acanthosis, epidermal basal layer pigmentation with an irregular distribution, focal mild lymphohistiocytic infiltrate in the papillary dermis and dermal–epidermal junction, and discrete pigmentary incontinence (Figs 2–4). The mast cell population was normal. A further biopsy 1 year later showed similar findings.Figure 1. Multiple brown macules involving the trunkDownload figure to PowerPointFigure 1. Multiple brown macules involving the trunkDownload figure to PowerPointFigure 2. Mild inflammation in the papillary dermis and dermal–epidermal junction with focal lichenoid changes (hematoxylin and eosin, ×40)Download figure to PowerPointFigure 2. Mild inflammation in the papillary dermis and dermal–epidermal junction with focal lichenoid changes (hematoxylin and eosin, ×40)Download figure to PowerPointFigure 3. Mild inflammation in the papillary dermis. Melanin pigmentation with an irregular distribution in the epidermal basal layer (hematoxylin and eosin, ×250)Download figure to PowerPointFigure 3. Mild inflammation in the papillary dermis. Melanin pigmentation with an irregular distribution in the epidermal basal layer (hematoxylin and eosin, ×250)Download figure to PowerPointFigure 4. Detail of the epidermal basal layer showing irregular melanin pigmentation; there are a few extravasated red cells and a melanophage in the papillary dermis (hematoxylin and eosin, ×400)Download figure to PowerPointFigure 4. Detail of the epidermal basal layer showing irregular melanin pigmentation; there are a few extravasated red cells and a melanophage in the papillary dermis (hematoxylin and eosin, ×400)Download figure to PowerPoint After 3 years of follow-up, mild spontaneous fading occurred in some of the trunk lesions, but most remained unchanged.
Idiopathic eruptive macular pigmentation: a case of 21 years' duration
Journal of the American Academy of Dermatology, 2003
Idiopathic eruptive macular pigmentation is a rare condition characterized by asymptomatic pigmented macules involving the neck, trunk, and proximal portions of the extremities. Age at onset usually varies from 1 to 20 years. The lesions usually appear abruptly and remit spontaneously over months to years. An unusual case of a 24-year-old woman with idiopathic eruptive macular pigmentation lasting 21 years was characterized by several periods of spontaneous resolution followed by recurrences. (J Am Acad Dermatol 2003;49:S280-2.) I diopathic eruptive macular pigmentation (IEMP) is a rare condition characterized by the presence of asymptomatic pigmented macules involving the neck, trunk, and proximal extremities. 1 There have been a total of 23 published cases of this disorder. 1-4 IEMP was first described by Degos et al 2 in 1978 to regroup their own cases and observations by other authors under various terms. In previous reports gradual and progressive disappearance of the lesions over several months to years seems to be the rule, and the disease does not generally relapse. This report describes the unusual case of a 24-year-old Indian woman with IEMP lasting 21 years and characterized by several periods of spontaneous resolution followed by recurrences.
Phacomatosis Pigmentokeratotica
Archives of Dermatology, 1998
Background: The epidermal nevus syndromes include different diseases that have the common feature of mosaicism. One of these has been recently identified and named phacomatosis pigmentokeratotica, in analogy to phacomatosis pigmentovascularis. It is characterized by an organoid nevus with sebaceous differentiation, a speckledlentiginous nevus, and other associated anomalies. It has been hypothesized that this syndrome is caused by a particular genetic mechanism known as the twin-spot phenomenon. Observations: We describe 3 patients manifesting an association of organoid nevus showing sebaceous differentiation and speckled-lentiginous nevus with associated anomalies and update the neurologic findings of a previously described patient. Hemiatrophy seems to be a common finding in all cases; hyperpathia, dysesthesia, and hyperhidrosis, as well as other neurologic defects, may be present. Conclusions: The findings in these patients allowed us to better delineate this syndrome. Further studies are needed to elucidate the underlying genetic defect. At present, however, the hypothesis that best explains this phenotype is twin spotting. Clinical recognition of this syndrome can contribute to the classification of the epidermal nevus syndromes and give insight into unusual genetic mechanisms occurring in humans.
The clinical recognition of lentigo maligna (LM) in the mottled chronic sun-damaged skin can be challenging, because it shares many clinical features with other pigmented macules that commonly arise on sun-damaged skin. These include solar lentigo, flat seborrheic keratosis, and pigmented actinic keratosis, but almost never "nevus." The reason nevus is not included in the differential diagnosis of LM can be explained by the fact that the stereotypical appearance of a facial nevus differs remarkably from that of an LM. Facial nevi in adults are usually nodular, dome-shaped, well-defined, and hypopigmented (ie, intradermal nevus of the Miescher type), whereas LM typically appears as a flat, ill-defined, and pigmented macule. Although this concept based on clinical observations sounds reasonable, clinicians apply it often only unconsciously and accept a given histopathologic diagnosis of a "junctional or lentiginous nevus" of a flat pigmented facial macule without the necessary criticism about its clinicopathologic validity.
Practical Guide to Dermatology, 2019
What Not To Miss • Other mucocutaneous features of lichen planus Key DDx • Post-inflammatory hyperpigmentation Work Up Pearls • Frequently a clinical diagnosis • Most commonly seen in adults with skin types III-V • Erythema dyschromicum perstans (EDP) is most commonly found on trunk and upper extremities and may have a rim of erythema in active lesions • Lichen planus pigmentosus (LPP) is most commonly found in photodistributed or intertriginous pattern (this is usually referred to as lichen planus pigmentosus inversus)
Syndromic nevoid hypermelanosis: Description of seven cases with a 10-year follow up
The Journal of Dermatology, 2010
Skin lesions can often be the only sign of an underlying systemic abnormality which will require further investigation. Several syndromic conditions are diagnosed after their cutaneous marker, which is in most cases a nevus. We report a neurocutaneous condition which we named ''syndromic nevoid hypermelanosis'' (SNH). We studied seven patients who presented with hyperpigmented disseminated macules (melanotic or pigmented nevi) as a cardinal sign. Neurological abnormalities were detected in all cases and skeletal dysmorphism in four. In spite of the genetic alteration that may be the cause of this disease, dermatologists should be able to diagnose it based on its semiological features and distinguish it from other neurocuataneous conditions. We consider SNH to be a distinct clinical entity that has not been clearly defined until now.