Rev. Med. Chir. Soc. Med. Nat., Ia şi – 2017 – vol. 121, no. 1 INTERNAL MEDICINE - PEDIATRICS ORIGINAL PAPERS 25 CLINICAL, LABORATORY AND THERAPEUTIC PROFILE OF LICHEN PLANUS Daciana Elena Brănișteanu 1 , A. Pintilie 1 , Andreea Dimitriu 1* , Anca Cerbu 1 , Delia Ciobanu 2 , A. Oanţă 3 , A. L. Tatu 4 “Grigore T. Popa” University of Medicine and Pharmacy Iasi Faculty of Medicine 1. Department of Medical Specialties (III) 2. Department of Morpho-functional Sciences (I) University of Medicine “Transilvania”, Braşov 3. Department of Dermatology “Dunarea de Jos“University, Galati Faculty of Medicine and Pharmacy 4. Department of Dermatology *Corresponding author. E-mail: dr.andreeadimitriu@gmail.com CLINICAL, LABORATORY AND THERAPEUTIC PROFILE OF LICHEN PLANUS (Ab- stract): Aim: Retrospective study of the clinical manifestations and clinical forms of lichen planus, investigation methods and therapeutic means using data from patients admitted to the Dermatology Clinic of the "Sf. Spiridon" County Clinical Emergency Hospital Iasi, in the in- terval January 1 st -December 30 th , 2015; the obtained results were compared with the data in the literature. Material and methods: Forty-five patients were included in the study. The data were interpreted by using various statistical notions: arithmetic mean, percentage distri- bution, standard deviation, coefficient of variation, "t-Student" test. Histopathological exam- ination was performed in most cases to enhance diagnosis certainty. Results and discussion: The analysis of the study group (29 women and 16 men) produced many results in agreement with literature data. In 2015 the prevalence of lichen planus in the patients admitted to the Clinic of Dermatology, regardless of clinical form was 4.01% with a female preponderance (female/male ratio 2: 1). The mean age of the study patients was 55.31 years and 79.98% of total cases were in the fourth and six decades of life. The main infectious risk factor for the development and progression of lichen planus is hepatitis C virus (13.3%). The most com- mon form of lichen planus (88.8%) was the cutaneous form. Conclusions: Lichen planus is a chronic autoimmune disease with undulating course and different clinical subtypes that can affect multiple body regions . Keywords: LICHEN PLANUS, PAPULE, AUTOIMMUNE DISEASES, LICHENOID REACTIONS. Lichen planus is a mucocutaneous in- flammatory dermatosis of uncertain etiolo- gy, with chronic or subacute course, often self-limited (1). The classic description of lichen planus eruption is given by the 5 Ps: purple, planar, polygonal, pruritic, papules (2). The estimated prevalence of lichen planus in the general population is in the range of 0.2% to 4%. It occurs more fre-