Porokeratosis is a hereditary skin disorder characterized by an expanding annular patch with a keratotic ridge, with six recognized clinical variants including porokeratosis of Mibelli and linear porokeratosis. Triggering factors include UV radiation and immunosuppression, while treatments consist of topical, surgical, and systemic methods. The prognosis indicates a risk of malignant transformation, particularly in larger, longstanding lesions in older adults.

1. Porokeratosisfb.com/groups/dermatologycourseonline

3. Porokeratosis
Hereditary disorder of
keratinization characterized by
expanding atrophic anular patch(es)
surrounded by prominent keratotic
ridge called the cornoid lamella

4. Porokeratosis
AD

5. Clinical Variants of
Porokeratosis

6. “6” CLINICAL VARIANTS

8. 1. Porokeratosis of Mibelli (PM)
2. Disseminated superficial actinic
Porokeratosis (DSAP)
3. Disseminated superficial
Porokeratosis (DSP)
4. Linear Porokeratosis (LP)
5. Porokeratosis palmaris et plantaris
disseminata (PPPD)
6. Punctate porokeratosis

10. POROKERATOSIS OF MIBELLI

11. Porokeratosis of Mibelli:
A classical lesion
showing an annular
plaque with normal or
atrophic centers
surrounded by a
keratotic ridge

12. hyperkeratotic border
(arrows) delimits the
lesion and accounts for
the roughness slightly
hypopigmented and
atrophic center

14. DSAP

18. LINEAR POROKERATOSIS

22. PPPD

27. PUNCTATE POROKERATOSIS

31. Triggering factors
of Porokeratosis

32. I. UV irradiation
II. Immunosuppression “6”
1. Transplantation
2. Diabetes mellitus
3. Leukemia
4. Lymphoma
5. HIV
6. Drugs

34. Histopathology of
Porokeratosis

43. Treatment of
Porokeratosis

44. I. TOPICAL
II. SURGICAL
III.SYSTEMIC

45. Topical “6”
1. Sun screens (as well as other sun
protection measures)
2. 5 fluorouracil
3. Imiquimod
4. Calcipotriol
5. Tretinoin cream
6. Salicylic acid

46. Complete resolution of porokeratosis of
Mibelli following Rx with topical 5-FU. twice
daily for 2 months (There are erythematous excoriation
sites of recent arthropod assaults)

47. Surgical “6”
1. Cryotherapy
2. Electrodesiccation
3. Dermablation
4. Laser: CO2 laser - Pulsed dye laser
5. PDT
6. Excision and grafting

48. Systemic
Retinoids may inhibit carcinogenesis;
1. Acitretin
2. Isotretinoin

50. Prognosis of
Porokeratosis

51. Prognosis
Malignant transformation (7% -
11.6%) Large, longstanding lesions &
linear –more likely to occur in older
adults.
1. SCC
2. Bowen’s disease
3. Basal cell carcinoma

53. REFERENCES
Dermatology Illustrated Study Guide &
Comprehensive Board Review 2012
Google images
emedicine.medscape.com
Presentation by Ahmed Essop Registrar
Department of Dermatology University of
the Pretoria Steve Biko Academic Hospital
dermnetnz.org
en.wikipedia.org

54. youThank