Speckled Lentiginous Nevus Syndrome Research Articles

Correspondence Concerning PTPN11 Mosaicism Causes a Spectrum of Pigmentary and Vascular Neurocutaneous Disorders and Predisposes to Melanoma

I read with great interest the article by Polubuthu et al. reporting on the detection of PTPN11 mutations in several mosaic conditions, i.e. phacomatosis spilorosea, nevus spilus, nevus roseus and speckled lentiginous nevus syndrome (Polubuthu et al., [in press]). One of the paper’s conclusions is that mosaic PTPN11 mutations in nevus spilus predispose to cutaneous melanoma. I wish to challenge such conclusion based on the following points.

Papular nevus spilus syndrome: old and new aspects of a mosaic RASopathy

The co-existence of papular nevus spilus (PNS) and ipsilateral extracutaneous abnormalities involving peripheral nerves of the skin or muscles was originally described as "speckled lentiginous nevus syndrome". To avoid confusion with macular nevus spilus, the condition was recently re-named "papular nevus spilus syndrome". In addition to 14 published cases, we identified six new cases via a search of the worldwide literature. New diagnostic criteria are suggested: (1) presence of a PNS; (2) presence of a neurological or skeletal abnormality which is usually ipsilateral to the nevus; and (3) absence of a nevus sebaceus. According to current knowledge, PNS syndrome is a rather rarely occurring, sporadic disorder that can be considered to be part of a spectrum of mosaic RASopathies, which includes isolated PNS, isolated nevus sebaceus, PNS syndrome, Schimmelpenning syndrome, and phacomatosis pigmentokeratotica.

Further Delineation of Speckled Lentiginous Nevus Syndrome

Speckled lentiginous nevus syndrome is a recently described condition, characterized by unilateral neurocutaneous manifestations consisting of: speckled lentiginous nevus, hyperhidrosis, muscular weakness and dysesthesia. Skeletal anomalies such as scoliosis, limb asymmetry, and psychiatric manifestations have been also reported. Herein, we report a case of speckled lentiginous nevus syndrome with skeletal anomalies and a pseudo-marfanoid phenotype.

Speckled lentiginous nevus syndrome with median nerve paresis: A rare syndrome with a new association

Speckled lentiginous nevus (SLN) represents a mosaic phenotype which consists of café au lait macule superimposed by melanocytic nevi. Recently, SLN syndrome has been characterized where ipsilateral neurological abnormalities have been reported in association with SLN with papular type of melanocytic nevi only. This case describes the presence of ipsilateral thenar muscle atrophy with median nerve paresis in nevus spilus which had melanocytic nevi of the macular type alone, thus delineating a new association in SLN syndrome, hitherto unreported.

Speckled Lentiginous Nevus Syndrome: Central Nervous System Abnormalities as a Critical Diagnostic Feature

Speckled Lentiginous Nevus Syndrome: Central Nervous System Abnormalities as a Critical Diagnostic Feature

Widespread Nevus Spilus Associated with Torsion Dystonia: A Case Report

Usually speckled lentiginous nevus or nevus spilus is a small solitary lesion consisting of a light tan patch with numerous dark brown macules or papules (or both) within it. It is occasionally associated with complex birth defects such as phacomatosis pigmentovascularis, phacomatosis pigmentokeratotica, or speckled lentiginous nevus syndrome. Uncommon presentations include large segmental lesions that may or may not be systematized and can sometimes be associated with other anomalies. We hereby report a 6-year-old Caucasian patient with systematized nevus spilus associated with torsion dystonia, a combination not published thus far.

Intracranial cavernoma and speckled lentiginous nevus: extending the spectrum of phakomatoses?

Phakomatosis refers to several malformation syndromes with simultaneous involvement of the skin, the eye, and the central nervous system by developmental lesions. Speckled lentiginous nevus (SLN), a subtype of congenital melanocytic nevi, is usually an isolate, harmless finding. Here, we report the case of a 52-year-old woman with congenital left laterocervical SLN associated with an ipsilateral intracranial extra-axial cavernous angioma, a yet not described association to date. After revision of the literature, we suggest that both these lesions could be correlated in the setting of an atypical, yet unclassifiable form of phakomatosis, such as phakomatosis pigmentovascularis or SLN syndrome. We also propose that patients with bizarre, geometrical, pigmented or vascular cervicocranial skin lesions should undergo a thorough neurologic and ophthalmologic evaluation.

Speckled Lentiginous Nevus Syndrome Associated with Musculoskeletal Abnormalities

Speckled lentiginous nevus syndrome is a recently described neurocutaneous disorder characterized by speckled lentiginous nevus in association with hyperhidrosis, skin dysesthesia, and muscular weakness in an ipsilateral manner. We report a 9-year-old boy with a large speckled lentiginous nevus on his trunk, bilateral upper extremities, and neck associated with hyperhidrosis and nonspecific pain in the distribution of the nevus in addition to prominent upper extremity asymmetry and scoliosis. Similar musculoskeletal abnormalities have been reported in patients with phacomatosis pigmentovascularis and phacomatosis pigmentokeratotica which feature speckled lentiginous nevus; however, this patient demonstrates striking musculoskeletal abnormalities in the absence of coexisting vascular lesions or nevus sebaceous.

Neurocutaneous disorders

Neurocutaneous disorders

Dohi Memorial Lecture. New aspects of cutaneous mosaicism.

The concept of cutaneous mosaicism has today been proven at the cellular level in at least fifteen different skin disorders. We can distinguish five different patterns of mosaicism, including the phylloid pattern and the lateralization pattern. Etiologically, cutaneous mosaics can be divided into two large categories, epigenetic mosaicism and genomic mosaicism. All forms of epigenetic mosaicism known so far, including the various patterns of X-inactivation, appear to be caused by the action of retrotransposons. A new concept is functional autosomal mosaicism transmittable through the action of retrotransposons, which has been described in mice and dogs and may explain, for example, the familial occurrence of pigmentary mosaicism along the Blaschko lines in human skin. Among the examples of mosaicism of autosomal lethal mutations, phylloid hypomelanosis is a recently recognized neurocutaneous entity caused by mosaic trisomy 13. Possible examples of a type 2 segmental manifestation now include at least fifteen different autosomally dominant skin disorders. This phenomenon is most frequently found in glomangiomatosis, cutaneous leiomyomatosis, and disseminated superficial actinic porokeratosis. Recently proposed examples of didymosis (twin spotting) include cutis tricolor, paired patches of excessive or absent involvement in Darier disease, and didymosis aplasticosebacea characterized by coexistent aplasia cutis congenita and nevus sebaceus. To the list of possible examples of paradominant inheritance, cutis marmorata telangiectatica congenita and speckled lentiginous nevus syndrome have now been added. Revertant mosaicism giving rise to unaffected skin areas in autosomally recessive cutaneous traits will certainly likewise be recognized more often when clinicians are bearing this concept in mind. Such cases can be taken as examples of "natural gene therapy".