1. Bluish Gray Pigmented Macule on Right Cheek

Sunil Kumar Kothiwala¹

(1)

Dr Kothiwala’s SkinEva Clinic, Jaipur, India

Sunil Kumar Kothiwala

Keywords

Dermal melanocytosisNevus of otaNevus fuscoceruleus ophthalmomaxillarisOculodermal melanocytosis

A 22 years old male patient presented with single hyperpigmented macule on left cheek. Patient noticed initial lesion in form of asymptomatic hyperpigmented macule at age of 12–13 years, which gradually increased in size and darken in color but now since last 1–2 years it is stable. He had not taken any treatment for this and the family history was also non-contributory. On examination there was single unilateral blue-to-gray speckled or mottled coalescing smooth surfaced patch involving malar and forehead area of left side of face. Slight pigmentation of the ipsilateral nasal ala was appreciable. Ocular examination showed involvement of sclera in form of grey-blue pigmentation (Fig. 1.1). Oral cavity was not involved.

../images/471276_1_En_1_Chapter/471276_1_En_1_Fig1_HTML.jpg — Figure 1.1

Young male is having bluish colored large macule on left cheek with scleral involvement

Based on this clinical information what is your diagnosis?

(a)

Spilus nevus
(b)

Nevus of Ota
(c)

Café-au-lait macule
(d)

Segmental lentigenosis

Histopathology showed elongated dendritic melanocytes around collagen bundles in superficial dermis.

Diagnosis

Nevus of Ota

Discussion

Nevus of Ota is a type of dermal melanocytosis characterized by unilateral bluish gray mottled pigmented macule with or without extracutaneous involvement. Histopathology shows dermal dendritic melanocytes deep within dermis. Various treatment modalities including lights and lasers had been tried with variable success.

During fetal development, normally melanocytes migrate from the neural crest to the dermal-epidermal junction (DEJ). However, these melanocytes may occasionally fail to reach at DEJ and remain entrapped in dermis where due to Tyndall effect brown color of these nevus cells give bluish gray color to skin surface. Exact etiology is not known but specific mutations have been detected within the dermal melanocytes, most often GNAQ or GNA11 suggesting a link between nevus of Ota and uveal melanoma. Several theories have been put forward which include: dropping-off of epidermal melanocytes, migration of hair bulb melanocytes, reactivation of pre-existing latent dermal melanocytes, which are triggered by dermal inflammation, UV radiation or hormonal changes during pregnancy [1].

There are four types of dermal melanocytosis: nevus of Ota, nevus of Ito, nevus of hori, and Mongolian spot (Table 1.1).

Table 1.1

Different types of dermal melanocytosis

Type	Epidemiology	Onset	Clinical	Distribution	Histopathology	Associated features
Nevus of Ota	Asian (Japanese), female	Early infancy or adolescent	Blue-gray speckled pigmentation	In distribution of ophthalmic and maxillary branches of trigeminal nerve	Elongated dendritic dermal melanocytes in dermis	Glucoma Ocular melanoma Has been reported with Neurofibromatosis type 1
Nevus of Ito	Asian and female	Early infancy or adolescent	Blue-gray speckled pigmentation	In distribution of Acromioclavicular nerve	Elongated dendritic dermal melanocytes in dermis	None
Mongolian spot	Asian, African and male	At birth or within first few weeks	Blue-gray uniform pigmentation	Lower back, sacral region	Spindle shaped dendritic melanocytes in deep dermis	Usually resolve within 1 year Extra sacral lesions tend to persist more than 1 year Persistent Mongolian spots are associated with inborn error of metabolism
Nevus of hori	Asian and female	Second to fourth decade	Blue-gray speckled pigmentation	Area similar to nevus of ota but bilateral involvement	Elongated dendritic dermal melanocytes in dermis	None
Dermal melanocytic hamartoma		Congenital	Blue-gray speckled macules in a diffuse pigmented patch	Dermatomal	Dermal melanocytes in upper second/third dermis	None