Sections View Full Chapter Figures Tables Videos Annotate Full Chapter Figures Tables Videos Supplementary Content +++ Pigmentary Mosaicism ++ Figure 27-1 Pigmentary mosaicism This condition is characterized by areas of hypopigmentation following the lines of Blaschko. These are present from birth or evolve during early childhood. The lesions may be generalized, with individual areas of hypopigmentation assuming blotchy, whorled, or streaked patterns. Graphic Jump LocationView Full Size||Download Slide (.ppt) ++ Figure 27-2 A very small number of patients with this pigmentary disorder have central nervous system disease, usually manifest as seizures or mental retardation. Other reported abnormalities include skeletal and ocular defects. This condition was formerly called hypomelanosis of Ito or incontinentia pigmenti achromians. Graphic Jump LocationView Full Size||Download Slide (.ppt) ++ Figure 27-3 Pigmentary mosaicism In this form of mosaicism, there are lines of hyperpigmentation that follows lines of Blaschko. In this patient, there is a linear pattern on the extremities and a whorled pattern on the trunk. This condition was formerly referred to as “linear and whorled nevoid hypermelanosis.” The hyperpigmentation may be present at birth or develops shortly thereafter, spreading during the first 2 years of life, at which time it stabilizes. Graphic Jump LocationView Full Size||Download Slide (.ppt) +++ Nevus Depigmentosus (Achromicus) ++ Figure 27-4 Nevus depigmentosus (achromicus) These are localized areas of hypopigmentation that are usually present at birth. The lesions may be irregular in size and shape and occasionally follow a linear or segmental pattern. Electron microscopic study of these areas suggests that melanosomes are not being transferred from melanocytes into surrounding keratinocytes. There are no associated abnormalities. It is best considered as a more subtle form of pigmentary mosaicism, also resulting from a somatic mutation during embryogenesis. Graphic Jump LocationView Full Size||Download Slide (.ppt) +++ Nevus Anemicus ++ Figure 27-5 Nevus anemicus This benign lesion develops at birth or in early childhood. Rubbing the area causes the surrounding skin to turn red, while the area itself maintains its white color. Nevus anemicus does not represent a loss of pigment, but rather a constriction of blood vessels, due to a local increased sensitivity to catecholamines. Graphic Jump LocationView Full Size||Download Slide (.ppt) +++ Carotenemia ++ Figure 27-6 Carotenemia The vegetable pigment carotene is widely distributed in carrots, lettuce, squash, and many other vegetables and fruits. A diet that is very rich in these foods results in a yellowish-orange discoloration of the skin. This appearance is usually localized to the palms and soles (note the hand on the left in Fig. 27-6) but may also involve the skin of the face. The presence of normal sclera distinguishes the clinical appearance of this condition from that of jaundice. Return to normal skin color follows a reduction in dietary intake of carotene. Graphic Jump LocationView Full Size||Download Slide (.ppt) +++ Waardenburg Syndrome... Your Access profile is currently affiliated with [InstitutionA] and is in the process of switching affiliations to [InstitutionB]. Please select how you would like to proceed. Keep the current affiliation with [InstitutionA] and continue with the Access profile sign in process Switch affiliation to [InstitutionB] and continue with the Access profile sign in process Get Free Access Through Your Institution Learn how to see if your library subscribes to McGraw Hill Medical products. Subscribe: Institutional or Individual Sign In Error: Incorrect UserName or Password Username Error: Please enter User Name Password Error: Please enter Password Sign in Forgot Password? Forgot Username? Download the Access App: iOS | Android Sign in via OpenAthens Sign in via Shibboleth You already have access! Please proceed to your institution's subscription. Create a free profile for additional features.