Clinical and dermatoscopic correlation in facial melanosis: A cross-sectional study at a tertiary hospital

Abstract

Background: Facial pigmentary disorders are a group of heterogeneous entities, sharing a common clinical feature of altered pigmentation of the face. The overlapping features among the different clinical entities of facial hyperpigmentation may be differentiated by dermatoscopy. Objective: The objective was to evaluate the different types of facial melanosis and their dermatoscopic findings. Methods: This non-interventional, cross-sectional study was conducted at our dermatology department over a period of one year. All clinically diagnosed cases of facial melanosis were included in our study and their dermatoscopic evaluation was performed. Results: We included 500 patients with facial melanosis. While 370 patients were female, 130 were males. Three hundred patients had melasma, 59 (lichen planus pigmentosus) had LPP, 40 had Riehl’s melanosis, while 35 had frictional melanosis. Other dermatoses included acanthosis nigricans, ashy dermatosis, and poikiloderma of Civatte, to name a few. The most common dermatoscopic finding in our study evident in almost all cases of facial melanosis was exaggerated pseudo-reticular hyperpigmentation. The unique observation in our study, the reticulo-globular pattern seen in melasma, was thin and in the shade of brown pigmentation, whereas in LPP and ashy dermatosis, it was comparatively thicker and grayish-brown in color. The other specific finding observed was telangiectasia due to topical steroids, more prominent and enlarged than telangiectasia due to sun exposure in melasma and poikiloderma of Civatte. Conclusion: This study highlights the clinical and dermatoscopic features of facial melanosis. Further research is required in this field of dermatoscopic evaluation of facial melanosis to define more accurate diagnostic features as a facial biopsy is mostly refused by the patients, yet meanwhile, clinical evaluation should not be neglected. Study Limitations: The limitations of our study were the lack of direct histopathological correlation and the inclusion of both therapy-naive patients and patients on therapy. Key words: Facial melanosis; Dermatoscope; Melasma