Dermale naevus - Veelgestelde vragen en antwoorden over huidaandoeningen

Deterrence and Patient Education

Deterrence and patient education regarding nevus anemicus are centered on dispelling misconceptions and promoting understanding of this benign condition. Healthcare providers play a crucial role in educating patients and caregivers about the harmless nature of nevus anemicus, emphasizing its stable course and lack of associated health risks. Patients should be informed that nevus anemicus does not require active treatment unless for cosmetic reasons, and interventions such as laser therapy are generally ineffective.

Key clinical pearls of nevus anemicus provide essential insights into its benign nature, varied presentations, and management implications, as mentioned below.

Congenital onset: Most commonly observed at birth or during early childhood and remains stable throughout life.

Benign nature: Generally asymptomatic and benign, with no associated systemic complications or health risks.

Diagnosis: Clinical diagnosis is based on characteristic features, differentiation from other hypopigmented conditions like vitiligo and nevus depigmentosus is crucial.

Association with NF1: In some cases, nevus anemicus may be associated with NF1, necessitating further evaluation if other NF1 features are present.

Psychosocial impact: Educating patients about the harmless nature of the condition is essential to alleviate anxiety related to its appearance.

Introduction

Nevus anemicus is an uncommon congenital vascular anomaly characterized by hypopigmented cutaneous macules and patches. This lesional pallor results from localized hypersensitivity to catecholamines, which causes vasoconstriction. First identified by Vorner in 1906, nevus anemicus is distinguished by its lack of erythema in response to trauma, heat, or cold. Nevus anemicus is often mistaken for other skin conditions, such as vitiligo or nevus depigmentosus, and presents a unique diagnostic challenge in dermatology.[1]

All types of phakomatosis pigmentovascularis are characterized by the presence of nevus flammeus (port-wine stain). Researchers have observed nevus anemicus in close proximity to capillary abnormalities of the port-wine stain type, which are believed to be caused by somatic recombination. Phakomatosis pigmentovascularis type II includes Mongolian spots (congenital dermal melanocytosis), type III includes nevus spilus, and type IV includes both nevus spilus and Mongolian spots.

In individuals with NF1, nevus anemicus tends to appear at a younger age compared to those without it (mean age 10 versus 17). Importantly, the presence of nevus anemicus in NF1 patients does not increase the risk of other NF1-related manifestations, such as optic gliomas. Conversely, Legius syndrome, which resembles NF1 with features such as café-au-lait spots and intertriginous freckling, does not include nevus anemicus.[6][7]

Treatment / Management

In rare cases where cosmetic treatment is desired, options are limited due to the condition's vascular nature. Laser therapy, commonly used for other skin pigmentations, is ineffective for nevus anemicus. Educating patients about the condition and providing support for any psychological distress caused by its appearance are essential aspects of management.

The diagnosis of nevus anemicus requires healthcare professionals to rule out other conditions in the leukoderma differential diagnosis. These include, but are not limited to, vitiligo, pityriasis alba, nevus depigmentosus, tinea versicolor, tuberous sclerosis, halo nevus, piebaldism, Hansen disease (leprosy), and physical leukodermas (mechanical, chemical, or thermal). Achromic nevus, postinflammatory hypopigmentation, progressive macular hypomelanosis, and scarring can also be mistaken for nevus anemicus.

Diascopy, which involves applying pressure to the lesion and the adjacent unaffected skin with a glass slide, can differentiate nevus anemicus from other pale lesions. In contrast to true depigmenting disorders, a Wood lamp examination does not accentuate nevus anemicus and may render the lesion inapparent. The lesion remains unaffected by the application of friction, cold, or heat. Therefore, scratching a line across both the lesion and the adjacent skin will induce erythema in the normal skin but not within the nevus anemicus lesion.

Vitiligo is characterized by well-demarcated depigmented macules and patches with irregular borders. These areas may have a surrounding rim of hyperpigmentation or erythema and may also include white hairs within the lesion.

Nevus depigmentosus presents as hypopigmented patches within the first 3 years of life but does not exhibit the characteristic lack of redness in response to trauma, heat, or cold seen in nevus anemicus.

Pityriasis alba is most often diagnosed in patients with associated atopic dermatitis, while tinea versicolor presents as hypopigmented macules after increased episodes of diaphoresis. Unlike nevus anemicus, the last 2 lesions do not have a congenital onset.

Introduction

Nevus comedonicus (NC) is a rare skin disorder. In this review, we will provide an update on clinical features, pathogenesis, and treatment options.

Epidemiology

The prevalence of NC has been estimated from 1 in 45,000 to 1 in 100,000, with no gender or racial preference [1, 3]. In 50% of patients, the condition develops shortly after birth and in the majority of patients lesions appear before the age of 10 [4–6]. Single cases of delayed development of NC and NCS at later age have been reported [4–6].

Clinical Characteristics

NC lesions might present with various patterns of distribution: unilateral, bilateral, linear, interrupted, segmental, or blaschkoid (Figs. 1 , ​ ,2 2 and ​ and3) 3 ) [3].

Nevus comedonicus: plaque-like lesion with wide open follicles on the neck (44-year-old Caucasian male)

Stages of treatment of a 29-year-old Asian male with linear nevus comedonicus of the leg with multiple follicular openings. a Presentation of linear nevus comedonicus with multiple follicular openings. b Surgical excision. c Three weeks after surgical excision. d With compression garment to avoid postsurgical lymphedema

Nevus comedonicus of the neck with pseudoepithelial epidermal hyperplasia in a 39-year-old Caucasian