Linear and whorled hypermelanosis

Linear and whorled nevoid hypermelanosis is a sporadic pigmentary anomaly occurring within the first weeks of life, characterized clinically by swirls and streaks of macular hyperpigmentation following the lines of Blaschko. Histologically it shows only epidermal melanosis. Underlying chromosomal mosaicism has been demonstrated in only a few published cases. Progressive cribriform and zosteriform hyperpigmentation is considered to be the localized variant of linear and whorled nevoid hypermelanosis. We report a retrospective study on 16 children referred consecutively over a 10-year period for evaluation of segmental, linear or swirled hyperpigmentation distributed along the lines of Blashko, consistent with a diagnosis of linear and whorled nevoid hypermelanosis. Associated abnormalities were found only in one out of six patients with the diffuse form (linear and whorled nevoid hypermelanosis-type) and in none of the remaining 10 children presenting the unilateral form (progressive cribriform and zosteriform hyperpigmentation-type). A long-term follow-up did not disclose further abnormalities. The authors discuss the nosologic position of this entity with respect to hypomelanosis of Ito. Linear and whorled nevoid hypermelanosis and hypomelanosis of Ito should be not considered single entities, but be rather grouped as a heterogeneous collection of nonspecific pigmentary disorders caused by genetic mosaicism. Skin findings in these diseases can differ according to the pigmentation in the normal cell line and whether the second line contains more or less melanosomes than the normal skin of the individual exhibiting mosaicism.     

Pigmentary disorders in oriental skin

Brown hyperpigmented disorders may be melanotic in which there is a normal number of epidermal melanocytes but melanin pigment is increased in the epidermis (eg, melasma), melanocytotic, in which melanocytes are increased (eg, café-au-lait macules), and nonmelanotic hyperpigmentation (eg, minocycline pigmentation). Blue hyperpigmented disorders may also be melanotic in which there is a normal number of epidermal melanocytes, but melanin pigment is present in the upper dermis (eg, gray/slate pigmentation in Riehl's melanosis), melanocytotic in which melanocytes are present in both the epidermis and dermis (eg, blue pigmentation in Nevus Ota and Mongolian spot), and nonmelanotic hyperpigmentation in which pigment is present in the deep dermis (eg, blue pigmentation in tattoos). Hypomelanosis (leukoderma) may be divided histopathologically into melanocytopenic disorders on which melanocytes are absent (eg, Vogt-Koyanagi-Harada syndrome and vitiligo), melanopenic disorders in which melanocytes are present but melanin is reduced (eg, nevus depigmentosus and incontinentia pigmenti achromians), and nonmelanotic disorders in which melanin pigmentation is unaffected (nevus anemicus) and the pigmentary abnormality is caused by something other than melanin. There are numerous pigmentary disorders in the oriental skin, and some of them are either characteristic to or established in the orientals. Importantly, a number of congenital hypermelanotic and hypomelanotic diseases (eg, nevus depigmentosus, incontinentia pigmenti, and incontinentia pigmenti achromians, take a distribution following to the Blaschko's line.     

Unusual halo nevi--darkening rather than lightening of the central nevus.

Although the classic halo nevus is a brown nevus with a surrounding rim of depigmentation, i.e. a stage I halo nevus, these nevi can have several clinical stages. The central nevus may lose its pigmentation and appear pink with a surrounding halo (stage II), the central papule may disappear leading to a circular area of depigmentation (stage III) or the depigmented area may repigment (stage IV), leaving no trace of its prior existence. Herein we describe an unusual phenomenon--darkening of the central nevus rather than lightening--following the appearance of the halo phenomenon. An 18-year-old boy who had multiple atypical nevi developed multiple halo nevi beginning at the age of 12 years. Following the appearance of the peripheral halos, 2 of his nevi that were originally solid medium brown in color darkened and the hyperpigmentation had a reticulated pattern with perifollicular sparing. One possible explanation is a postinflammatory hyperpigmentation induced by the infiltrating lymphocytes.     

Morphologic changes of acquired melanocytic nevi with eccentric foci of hyperpigmentation ("Bolognia sign") assessed by dermoscopy

BACKGROUND: Melanocytic nevi with eccentric foci of hyperpigmentation ("Bolognia sign") can be considered as a melanoma-simulating type of acquired melanocytic nevus. We report on the morphologic changes of this type of melanocytic nevus over a 39-month period of dermoscopic follow-up. OBSERVATIONS: A 5-year-old girl had a 4-mm brown papule with a peripheral blue-black area on her right upper arm. The eccentric focus of the hyperpigmentation corresponded dermoscopically to a blue-gray area of pigmentation associated with irregular brown-black globules or dots and partially with a superficial black network. After 39 months, a globular type of acquired melanocytic nevus was detectable, which clinically and dermoscopically appeared to be completely benign. A nearly identical situation was observed in 5 other melanocytic nevi, underlining the involution of the pigmented foci in these nevi. The histopathologic diagnoses of 2 lesions were consistent with a compound type of acquired melanocytic nevus with eccentric foci of hyperpigmentation. CONCLUSIONS: Dermoscopy allows identification of a morphologic pathway of modifications, probably typical for this type of melanocytic nevus in children, and therefore enables avoidance of surgical excision with attendant hypertrophic scarring in children. Conversely, in adults, when dermoscopic follow-up of melanocytic nevi reveals eccentric foci of hyperpigmentation, surgical excision of the lesion is indicated.     

Progressive cribriform and zosteriform hyperpigmentation: a clinicopathologic study

Background  Progressive cribriform and zosteriform hyperpigmentation (PCZH) is a disorder of pigmentation. Although several cases of PCZH have been reported, no clinicopathologic studies of the condition have been published in the English‐language literature. Objectives  The purpose of this study was to determine the clinical characteristics and histologic findings of PCZH. Methods  Between 1999 and 2009, 30 patients were diagnosed with PCZH in our Department of Dermatology. Medical records, clinical photographs, and pathologic findings for each patient were retrospectively reviewed. Results  The patients included 16 men and 14 women. The mean age at onset was 14.27 years. The trunk was the most common site of involvement. Microscopic examination showed an increased level of melanin pigment in the basal cell layer compared with adjacent normal skin, although no significant difference existed in the number of melanocytes. Pigmentary incontinence was observed in 13 of 30 cases. Conclusions  There was no significant difference in prevalence, age at onset, and duration of lesions between male and female patients with PCZH. The lesions corresponded to the lines of Blaschko and were localized rather than exhibiting diffuse patterns. A common feature of the histopathologic findings was higher melanin content in the lesions than in normal skin but with no significant difference in the number of melanocytes.     

Melanoma within naevus spilus: 5 cases

BACKGROUND: Nevus spilus is defined as café-au-lait macules with dark maculopapular speckles. Histologically, it has the aspect of lentigo associated with nevocellular nevus. There are 3 types of nevus spilus: small or medium-sized (<20 cm), giant and zosteriform. Malignant transformation of nevus spilus is rare. PATIENTS AND METHODS: We analyzed the cases of 5 patients presenting melanoma within nevus spilus as well as 20 published cases. The evaluation criteria were: for nevus spilus: size, type, topography, age of onset and presence of dysplastic nevi within the nevus spilus; for melanoma: clinical aspect, histological type, thickness, level and age at diagnosis. The presence of other risk factors for melanoma was noted. RESULTS: The 14 women and 11 men had a mean age of 49 years at melanoma diagnosis. Type of nevus spilus was: small or medium-sized (15 cases), zosteriform (6 cases) and giant (4 cases). Only 3 nevi spili were<4 cm in diameter. Nevus spilus was present since birth (11 cases), childhood (7 cases), after the age of 20 years (3 cases) and was unspecified in 4 cases. Three of our five patients had other risk factors for melanoma. Two patients were presenting 2 melanomas within nevus spilus. The histological type of melanoma was not specified in 8 cases but SSM was the most common type (13 cases). Median Breslow thickness was 1.25 mm (0.27 to 8 mm) for the 19 cases in which it was specified. CONCLUSION: The following criteria appeared to be associated with risk of developing melanoma in nevus spilus patients: nevus spilus present since birth, nevus spilus over 4 cm in diameter, and giant or zosteriform nevus spilus. Development of melanoma within nevus spilus is a rare event. Consequently, guidelines for follow-up of nevus spilus cannot be defined. However, follow-up is recommended, and in particular, self-examination.     

Infant with abnormal pigmentation, malformations, and immune deficiency.

An infant had swirling hyperpigmentation, streaks of hypopigmentation, abnormal T-cell function, cleft palate, patent ductus arteriosus, and arrhinencephaly. This pattern of abnormalities is distinct from other disorders with abnormal pigmentation and malformations; such as incontinentia pigmenti, incontinentia pigmenti achromians, and the epidermal nevus syndrome.     

Pigmentvermehrung bei Schmidt-Syndrom (polyglanduläres Autoimmunsyndrom Typ II)

An 18-year old man presented with increasing pigmentation in multiple nevi as well as so -called “eruptive nevi” over a 24 month period. The first excisonal biopsy was from a plantar nevus which showed melanocytic hyperplasia. Following excisions of both hyperpigmented and newly appearing nevi showed only increased pigmentation. Two years after the first examination Addison-like hyperpigmentation was noticed in typical locations. Both Addison disease and Hashimoto thyroiditis were then confirmed by elevated serum levels of ACTH, TSH, and decreased levels of cortisol and L-thyroxine. This confirmed the diagnosis of Schmidt syndrome as part of polyglandular autoimmune disease (PGAS) type II. After another 18 months of treatment with hormone substitution of L-thyroxine and hydrocortisone, the hyperpigmentation resolved and the hyperpigmented nevi decreased in number.     

Additional conjunctival and penile pigmentation in Laugier-Hunziker syndrome: a report of two cases

BACKGROUND: Laugier-Hunziker syndrome is a rare acquired hyperpigmentation of the oral mucosa and lips which is often associated with longitudinal melanonychia. We report two patients exhibiting the classical features of Laugier-Hunziker syndrome with additional and previously unreported conjunctival and penile pigmentation. PATIENTS AND METHODS: Two patients presented with a history of progressive acquired macular pigmentation of the oral mucosa, the lips, the ocular conjunctiva and the penis. Longitudinal melanonychia was found in one patient. Microscopic features (basal epithelial melanosis, moderate acanthosis and superficial pigmentary incontinence) and ultrastructural details (increased number of normal-appearing melanosomes inside basal keratinocytes and dermal melanophages) were characteristic of Laugier-Hunziker syndrome. CONCLUSIONS: These two observations illustrate the topographical variations of Laugier-Hunziker syndrome and highlight the need to expand the originally described features to include more widespread areas of hyperpigmentation.     

The role of reflectance confocal microscopy in the diagnosis and management of pigmentary disorders: A review

Background

Reflectance confocal microscopy (RCM) has quickly transitioned from a research tool to an adjunct diagnostic bedside tool, providing the opportunity for noninvasive evaluation of skin lesions with histologic resolution. RCM is an optical imaging technique that uses near-infrared excitation wavelengths and safe low-power lasers. En-face images of different skin layers (up to the superficial dermis) are acquired in grayscale based on the reflective indices of tissue components. Melanin has the highest reflective index (contrast) and appears bright on RCM.

Aims

We present a review of the current literature on the use of RCM in the diagnosis and management of pigmentary disorders.

Methods

We reviewed PubMed and Ovid Medline databases from January 2000 to June 2021, using MeSH key terms: “reflectance confocal microscopy, confocal laser scanning microscopy, pigmentary disorders, treatment, melasma, vitiligo, freckles, solar lentigo, lentigo, tattoo, complications, melanoma, skin cancers, pigmented lesions, post inflammatory, melanin, photoaging” to identify studies and review articles discussing the use of RCM in the diagnosis and management of pigmentary disorders.

Results

RCM findings of pigmentary disorders were divided into the following categories: (1) disorders of increased pigmentation (post-inflammatory hyperpigmentation, melasma, Riehl's melanosis, solar lentigines, ephelides, hori nevus, naevus of Ota, café-au-lait macules, melanocytic nevus, melanoma, nevus spilus, labial mucosal melanosis, and mucosal melanoma), (2) disorders of decreased pigmentation or depigmentation (post-inflammatory hypopigmentation, vitiligo, nevus depigmentosus, halo nevus), and (3) exogenous pigmentation (tattoo, ochronosis).

Conclusion

RCM has been explored and proven valuable for the evaluation and management of pigmentary disorders including melasma, vitiligo, solar lentigines, tattoo, and tattoo-related complications.     

Acneform lesions in Becker's nevus.

Three cases of Becker's nevus are described in which acneform lesions were confined strictly within the limits of the hyperpigmentation. The combined phenomenon has not been reported previously, and we conceive it to be either a rare variant of the anomaly or a still rarer coincidence of Becker's nevus and nevus comedonicus.     

Segmental lentiginosis with "jentigo" histologic pattern.

We report a case of segmental lentiginosis (unilateral lentiginosis), that is, asymmetric distribution of lentigines on one side of the body, in a 23-year-old woman. Lesions involved the right side of the face and the cervical region, mostly within the area of division of the trigeminal nerve. Histologic examination disclosed a lentiginous pattern as well as some nests of melanocytes at the dermal-epidermal junction (so-called jentigo pattern). Similar cases have been described in the literature under the term "zosteriform lentiginous nevus," which in our opinion makes for confusion since the same term has also been used to describe cases that fit the diagnostic criteria for speckled lentiginous nevus (nevus spilus).     

Zosteriform connective tissue nevus: a case report

Because of its distinctive clinical features and histopathological characteristics, zosteriform connective tissue nevus is considered a separate entity from other connective tissue nevi. Only two cases have previously been reported in the worldwide dermatological literature. Here we report a zosteriform connective tissue nevus in a 3-year-old boy with similar clinical presentation.     

The color of skin: brown diseases of the skin,nails, and mucosa

Brown diseases comprise disorders leading to hyperpigmentation in skin and nails. Melasma is an acquired skin disorder that is characterized by brownish macules that typically occur on the face. Schamberg disease, also known as progressive pigmented purpura, is characterized by brown pigmentation with pepper spots on their edges. We summarize the epidemiology, pathogenesis, histologic features, and treatment choices for additional brown diseases, including melasma, pigmented purpuric dermatoses, postinflammatory hyperpigmentation, drug-induced hyperpigmentation, and pigmentations due to systemic or physiologic conditions.     

A case of congenital mucinous nevus: a connective tissue nevus of the proteoglycan type

Mucinous nevus is a very rare entity and can be classified as both a cutaneous mucinosis (CM) and a connective tissue nevus (CTN). We describe the clinicopathologic features of an unusual case of mucinous nevus in a 14-year-old Korean boy who presented with zosteriform plaques of congenital onset.     

Macular pigmentation of uncertain aetiology revisited: two case reports and a proposed algorithm for clinical classification

Ashy dermatosis, erythema dyschromicum perstans, lichen planus pigmentosus and idiopathic eruptive macular pigmentation are various types of acquired macular hyperpigmentation disorders of the skin described in literature. However, a global consensus on the definitions of these entities is lacking. We report two cases of acquired macular (hyper)pigmentation of uncertain aetiology diagnosed as ashy dermatosis and attempt to clarify the various confusing nosologies based on existing literature. We infer that acquired small and large macular pigmentation of uncertain aetiology should be considered separate from that associated with lichen planus. We also propose a diagnostic algorithm for patients with acquired macular hyperpigmentation.     

The Laugier–Hunziker syndrome

Laugier and Hunziker described a syndrome consisting of asymptomatic benign areas of hyperpigmentation affecting the lips, buccal mucosa and, in 50%, the fingernails. We report a 67-year-old woman with the clinical features of Laugier-Hunziker syndrome in association with vulval pigmentation. Histology, immunohistochemistry and electron microscopy from the various areas of pigmentation on the body confirmed the benign nature of the pigmentation. We review potential causes of oral and genital pigmentation, and suggest an expansion of the original syndrome described by Laugier and Hunziker to include more widespread areas of benign hyperpigmentation, which may associated.     

Cafe au lait has hue of its own

Segmental pigmentation disorder is a pigmentation disorder (hypo- or hyperpigmentation) first described some 20 years ago. It appears early in life, is segmental, and usually has a sharp border in the midline. It can be confused clinically and histologically with several pigmentary disorders, especially with giant or segmental cafe-au-lait macules. The purpose of this article is to promote, revive, and refresh this somewhat neglected entity, and to further subdivide it into two types: segmental pigmentation disorder simplex and segmental cafe-au-lait. We illustrate our contention with case reports.     

Zosteriform connective-tissue nevus

Zosteriform connective-tissue nevus, because of its distribution and histopathologic characteristics, is considered to be a separate entity. The only previous case of zosteriform connective-tissue nevus to be reported in the American literature was in 1944. We report and discuss a similar case.