Title 1: Pseudomelasma title 2: what you didn t know about melasma

1. Title 1: Pseudomelasmatitle 2: what you didn�t know about melasma! By Dr Abdullah Al Somari Dr Saad Al Mohizea Dr Ghada Bin Seef 2007

2. What is your diagnosis?

3. Picture 1

4. How would you treat?

5. Picture 2

6. Melasma is not homogenous The site of melasma is different Melasma may respond to treatment What is the diagnosis then?

7. Pigmentary Demarcation Lines (PDL)

8. Normal Pigmentation Pigmentation is generally perceived as an adaptation response of humans to UV radiation considerable variation even in a single race: skin color of Caucasians ranges from fair to brown The constitutive pigmentation also differs: females having a lighter color than males Distribution of melanin is also uneven: in Caucasians the upper thigh is the darkest and the lumbar, the lightest area

9. PDL Pigmentary demarcation lines (PDL) were first described by Matzumoto on the upper and lower limbs of Japanese people in 1913 Also known as Futcher�s or Voight�s lines Pigmentary demarcation lines are borders of abrupt transition between more deeply pigmented skin and that of lighter pigmentation They do not correspond to Blaschko�s lines or dermatomal lines but to voigt� lines

10. Pathogenesis? More common in females More common in darker races PDLs are dominantly inherited Phylogenetic importance? Cutaneous Mosaicism? Neural influence? Strong hormonal influence

11. Mosaicism? Two types: functional mosaics, resulting from X inactivation or lyonization,and genomic mosaics, caused by postzygotic autosomal mutations. Could explain the familial aggregation and the female preponderance Either the maternal or paternal X chromosome is lyonized (deactivated) randomly, but it remains the same for all the descendants of that cell Because of this process the heterozygous state of various X-linked gene defects may lead to a cutaneous mosaic. Streaky or patchy pigmentation may be a clue to the presence of mosaicism

12. HORMONAL INFLUENCE Hormonal influence over pigmentary characteristics has been documented preponderance of females exhibiting these lines could be related to sex hormones High levels of Estrogen Progesterone and MSH Persistance of PDL after pregnancy with estrogen therapy Hormones are probably aggravating PDL and not causing it

13. Neural theory Maleville concluded that the axial-neural theory is the most commonly accepted in opposition to that of pigmentary mosaicism as defended by Krivo They coincide with cutaneous nerve distribution. Compression by the enlarged uterus of peripheral nerves issuing at S1�S2 is proposed as a mechanism of these changes in type B

14. Neural theory NEURAL control of pigmentation? Differences in melanogenesis noted across these lines my correspond to an absence or reduced expression of certain proteins between nerve endings in neural territories controlled by different homeobox gene during development

15. PDL is common! Body PDL Pigmentary changes are seen in nearly 85% of pregnant women About 25% of black Africans show sharply demarcated pigmentary lines either at the anterolateral upper arm or posteromedial part of the lower limbs (Type A and B) More in females (except type c with slight male preponderance) Can be associated with an erythematous component PDL over the face (6%) were found to have demarcation lines on the face (indians). lines were far more common in women (9%) than in men (0.75%) Positive family history in (61%)

16. History AND Examination Asymptomatic Strong family history (sister, mother) Homogeneous and sharply demarcated Symmetrical Associated with thyroid disease? ONSET AND COURSE All the facial PDL�S first made their appearance around puberty Whereas the classical types presentesd Earlier in childhood Facial PDLs become more apparent with advancing age.

17. SKIN BIOPSY Unremarkable except for hyperpigmentation of the basal cell layer without inflammatory infiltrate or melanophages in the upper dermis

18. Old groups(non facial)