1. Lichen Simplex Chronicus
Also known as Neurodermaitis
Causes
Atopic dermatitis results in a higher probability of developing lichen simplex chronicus.
Common factors: Insect bites, scars, acne keloidalis nuchae, xerosis, venous insufficiency, and asteatotic eczema
Psychological factors appear to play a role in the development or exacerbation of lichen simplex chronicus.
Anxiety has been reported to be more prevalent in patients with lichen simplex chronicus.
Neurodermatitis is a term formerly used interchangeably with lichen simplex chronicus, suggesting a role of anxiety or obsession as part of the pathological process of developing lesions.
Andrew’s Disease of the skin
Fitzpatrick’s color atlas of dermatology
Medical Therapeutic of Dermatology

2. Patient’s Data
Onset: gradual and insiduous
Cause: long continued rubing and scratching
Sex: females > males
Age: mid-to-late adulthood, with highest prevalence in persons aged years
Lesions:
Well-circumscribedsolid plaque of lichenification, arising from the confluence of small papules;
scaling is minimal except on lower extremities
Can result to rough, scratched (excoriated), thickened skin surface which may develop increased pigmentation (hyperpigmentation) as seen here on the front part of the foot, just below the leg
fully developed plaque has an outer zone of discrete, brownish papules and a central zone of confluent papules covered with scales.
52 year old female
Obese
Diabetic
Multiple pruritic slightly erythematous with hyperpigmented patches
Lower abdomen, inguinals and buttocks
2 months duration
Lesions flattened with postinflammatory pigmentation
Well demarcated papules vesicles, scales, excoriations at the borders

3. Lichen Simplex Chronicus
Patients
Lichenifiction:
thickened and leathery, exaggerated skin markings, criss- cross pattern striae in between them a flat topped, shiny smooth , quadrilateral facets
Site of predilection:
thickening of the skin:
Scalp, Nape of neck, Extensor forearms and elbows, Vulva and scrotum, Upper medial thighs, knees, lower legs, and ankles
Sign and symtoms:
paroxysmal pruritus
- intermittent
- May be intense
- Increases with nervous tension, stress
less -when patients are active scratching provides temporary relief.
52 year old female
Obese
Diabetic
Multiple pruritic slightly erythematous with hyperpigmented patches
Lower abdomen, inguinals and buttocks
2 months duration
Lesions flattened with postinflammatory pigmentation
Well demarcated papules vesicles, scales, excoriations at the borders

4. Lichen Simplex Chronicus

5. Treatment
aimed at reducing pruritus and minimizing existing lesions because rubbing and scratching cause lichen simplex chronicus.
High Potency Topical steroids
are the current treatment of choice because they decrease inflammation and itch while concurrently softening the hyperkeratosis
Usually applied under plastic or biosynthetic or hydrocolloid dressings overnight or for continuous 3 to 7 day periods
Intralesional injection of corticosteroids
Will induce involution most rapidly and is often the therapy of choice
For infected lesions, a topical or oral antibiotic can be considered

6. Prurigo Nodularis Chronic Etiology: unknown Contribute factors:
atopic dermatitis
anemia
hepatic diseases
pregnancy
renal failure lymphoproliferative disease
photodermatitis
gluten enteropathy
stress
insect bites.

7. Gender: Females> males Age: middle-aged and older persons. Lesion:
Prurigo Nodularis
Patients
Gender: Females> males
Age: middle-aged and older persons.
Lesion:
Multiple, firm, excoriated nodules arising at sites of chronically picked or excoriated skin
bilaterally symmetric with nodules that are either stable or increasing in number.
well-defined dome shapes up to 2 cm in diameter
Linear arrangement pea-sized or larger,
Can become verrucous and fissured
Bleeding and scarring
52 year old female
Obese
Diabetic
Multiple pruritic slightly erythematous with hyperpigmented patches
Lower abdomen, inguinals and buttocks
2 months duration
Lesions flattened with postinflammatory pigmentation
Well demarcated papules vesicles, scales, excoriations at the borders

8. Prurigo Nodularis
Patients
Site of predilection:
Chiefly on the anterior surfaces of the thighs and legs
Sign and symptoms:
Lesions slowly evolve
Paroxysmal pruritus: intermittent, unbearably severe, and relieved only by scratching to the point of damaging skin
bilaterally symmetric, with nodules that are either stable or increasing in number
52 year old female
Obese
Diabetic
Multiple pruritic slightly erythematous with hyperpigmented patches
Lower abdomen, inguinals and buttocks
2 months duration
Lesions flattened with postinflammatory pigmentation
Well demarcated papules vesicles, scales, excoriations at the borders

9. Prurigo Nodularis

10. Treatment Topical, oral, and intralesional corticosteroids
to decrease inflammation and sense of itching
to soften and smooth out firm nodules
Menthol, phenol, pramoxine, capsaicin cream,15 vitamin D-3 ointment,16 and topical anesthetics are some other topical agents used to reduce pruritus