background

methods(I) Review of the existing literature; and (II) information on our personal experience (clinical, laboratory and imaging data) on new cases with

resultsThe existing literature revealed 19 previous studies (35 cases) with pure cutaneous or syndromic cutis tricolor phenomena. Our personal experience included 5 unpublished patients (3 boys; 2 girls; currently aged 2 to 14 years) seen and followed-up at our Institutions in Italy who had: (I) skin manifestations of the cutis tricolor type (N=5); (II) skeletal abnormalities including small skull (n=2), obtuse angle of mandible (n=3), mild to moderate scoliosis (n=3), vertebral defects (n=3), and long bones bowing (n=3); mild psychomotor delay (n=3); epilepsy (n=2); anomalies of the corpus callosum (n=3); and cavum vergae (n =2).

conclusionsThis study further confirms and expands the overall phenotype of cutis tricolor. By literature review and personal experience we conclude that the skin abnormalities of the cutis tricolor type are stable over time; the skeletal defects are mild to moderate and do not progress or cause relevant orthopaedic complications; the neurological/behavioural phenotype does not progress and the paroxysmal events (when present) tend to decrease over time; there is a typical facial phenotype in some patients (long, elongated face, thick and brushy eyebrows, hypertelorism, deep nasal bridge with large bulbous nose and anteverted nostrils), which characterizes a somewhat distinct syndromic phenotype; some patients may develop early onset cataracts. The allelic dydymotic hypothesis of post-zygotic mutations likely involving the same gene loci could well explain the overall skin, bone, lens and nervous system phenomena of migration of different streaks of clones in the different tissues.