All the patients were subjected to the following:
I. Before treatment:
A. Consent: An informed written consent will be signed by each patient before enrolment in the study.
B. Detailed history taking :
• Personal history: name, age, sex, skin type, occupation, residence, marital status, and smoking.
* History of present illness: onset, course, duration of disease, precipitating factors and any medications.
* Past history of any associated systemic or dermatological diseases.
* Family history of any dermatological disease e.g. psoriasis, atopic dermatitis,….etc.
* Drug history.
C. Skin biopsy: Two 3 mm punch biopsies will be taken from the lesion from each patient under local anesthesia using (Lidocaine®). One for histopathology to confirm diagnosis of LSC and the other for measuring itching mediators in the lesion before treatment by enzyme-linked immunosorbent assay (ELISA)). Another biopsy will be taken from a non lesional skin from same patient for measuring itching mediators by ELISA. Biopsies for ELISA will be stored at -20 degree celsius in eppendorfs with 3 ml phosphate buffer saline (PBS) added to each eppendorf. Tissue samples with PBS will be homogenized by a grinder, then centrifuged for 20 minutes at 3000 revolutions per minute (rpm) speed, the supernatant will be removed to be added to the ELISA kit wells for Human Interleukin-31, Nerve Growth Factor and Substance P assays (itching mediators)
D. Clinical assessment:
1. Pruritus severity scale.
2. Scaling, erythema, lichenification excoriation scores
3. Visual analogue scale.
4. Investigator's Global Assessment.
E. Depression assessment: Beck Depression Inventory questionnaire will be used to assess the depression in each patient .
F. Therapeutic Intervention: Patients will be divided as discussed before. - Topical steroids used will be a moderate potency topical steroid.
* Fractional carbon dioxide laser sessions for groups A (1 and 2) by laser machine.
* Parameters of laser session: (Parameters will be adjusted according to skin type, lesion thickness and condition) Power 15 to 20 watt according to skin color. Dwell time 800 to1000 milliseconds. Spacing 600 micrometers. Stack 2
II. After treatment:
A. Assessment of biochemical efficacy (measuring itching mediators after treatment): After one month from the last session for group A and after one month from stoppage of steroids for group B, a skin biopsy from the plaque (from a nearby site to the former one) will be taken as discussed before for ELISA.
B. Assessment of clinical efficacy by scores as discussed before.
C. Depression assessment: Beck Depression Inventory questionnaire will be repeated.
D. Assessment of safety:
* Assessment of side effects of laser and their treatment:
Erythema, burning sensation, PIH, pruritus and/or pixilation. • Assessment of side effects of topical corticosteroids and their treatment: Atrophy, telangiectasia, hypopigmentation, hypertrichosis, purpura, ulceration, irritation, secondary infection.
• Assessment of side effects of skin biopsy and their treatment: Bleeding, secondary infection and/or Scarring.
