Lichen Planus Pigmentosus in North Africa: A Series of 17 Cases

Abstract

Background
Lichen planus pigmentosus (LPPig) is considered as a rare macular and pigmented variant of lichen planus. It is mainly reported
in Indian and Latino American patients.
Objective
The aim of this paper is to report the characteristics of this condition in Moroccan patients.
Patients and Methods
Patients attending a private dermatology practice, in Casablanca, Morocco, and presenting with LPPig were consecutively enrolled.
Inclusion criteria were the presence of macular pigmented lesions of the face, neck or arms, and/or cutaneous histology showing
pigment incontinence with basal cell vacuolization and lichenoid infiltrate. Patients with melasma or post-inflammatory pigmentation
were excluded. Demographic and medical data were collected.
Results
From January 2015 to December 2018, 17 patients were included, one man and 16 women, mean age 57.4±11 years. Ten patients
had phototype III and five phototype IV. The mean duration of the disease was 6.7±7 years. The lesions were located on the face
in all patients, with the involvement of the perioral area in 13 cases (76.4%), the forehead in 9 cases. The neck was involved in 9
cases (53%). In 7 cases (41%), frontal fibrosing alopecia was observed. Three patients had thyroiditis, three others had diabetes
mellitus. Histology was performed in six cases, showing pigment incontinence and basal vacuolization. Lichenoid infiltrate was observed
in four cases. Eleven patients were given tranexamic acid per os, 500 mg twice daily for 3 or 6 months. Topically, all patients
but one received hydroquinone, and sixteen high potency dermocorticoids to the lesions. An the follow-up, only four patients had
an excellent result with complete resolution of the lesions, in the others, the lesions stayed similar.
Conclusion
LPPig exits in North Africans although its prevalence is probably underestimated. This pigmentary disorder remains a challenging
disease for therapy.