Lichen planus pigmentosus

Therapeutic implications of dermoscopic findings in acanthosis nigricans: A clinical and histopathological study

Acanthosis nigricans is associated with numerous systemic disorders. These include endocrinological conditions such as, diabetes, acromegaly, Cushing's syndrome, thyroid dysfunction, as well as metabolic abnormalities like obesity and polycystic ovarian disease. Its association with visceral malignancy is known. Moreover, Acanthosis nigricans is known to be a cutaneous marker of insulin resistance (IR) and hyperinsulinemia. The primary aim of this study was to study clinical and histopathological patterns of acanthosis nigricans and its correlation with dermoscopic patterns and treatment implications. 103 patients clinically diagnosed as acanthosis nigricans were enrolled in the study. Clinical evaluation, dermoscopy, and skin biopsy was done for histopathological evaluation. Consistency was observed in the changes seen on dermoscopy with clinical and histopathological findings. Common dermoscopy findings were Crista Cutis, Sulcus Cutis, Papillary projections, hyperpigmented dots, crypts, and blotching Dermoscopic findings can be correlated with histopathological features. Dermoscopy allows visualization on higher magnification which helps to pick up subtle changes which are not visible to naked eye. Dermoscopy can be a useful tool to distinguish acanthosis nigricans from other pigmentary disorders in patients who are not willing for histopathological examination and helps in treatment making decisions.

Dermoscopy in the Evaluation of Pityriasis Versicolor: A Cross Sectional Study

Background:

Pityriasis versicolor (PV) is a superficial mycosis caused by Malassezia yeast; a lipophilic fungus. Dermoscopy may be a value addition in the diagnosis of PV in some cases, where results of KOH (potassium hydroxide) examination are ambiguous. There is paucity of Indian data on dermoscopy of PV.

Materials and Methods:

Thirty consecutive patients diagnosed clinically with pityriasis versicolor were recruited in this pilot cross sectional study. Patients were subjected to KOH mount of the skin scrapings from the lesions which were positive in all the patients. Dermoscopy was performed in all using Universal Serial Bus (USB) dermoscope [Dinolite AMZT 73915, Edge 3] and features were recorded for analysis.

Results:

Hypopigmented variant was the most common type (80%). Dermoscopic analysis revealed altered pigmentary network as most common finding (100%) followed by scaling seen in 25 cases (83.33%). Folliculocentric pattern was appreciated in 20 cases (66.67%). A characteristic contrast halo ring around the primary altered pigmentation was observed in 20 cases (66.67%). Invasion of hair follicles by yeast was evident in 6 patients (20%).

Conclusion:

Dermoscopy with characteristic features such as folliculocentricity, contrast halo sign, and yeast invasion of hair follicles can be a very useful aid in contributing towards diagnosing pityriasis versicolor.

Dermoscopy of Pigmentary Disorders in Brown Skin

Dermoscopy is a noninvasive technique for the diagnosis, prognosis, and monitoring of pigmentary disorders in brown skin. It can be used for the diagnosis of various facial melanoses, which can avoid the need for biopsy in many cases. It can also help in early identification of the adverse effect of topical steroids and hydroquinone when they are used for the treatment of these disorders. Dermoscopy can also reliably differentiate vitiligo from other disorders of hypopigmentation. It can also help in assessing the stability of vitiligo before surgery.