Mongolian Spots Are Not Always a Benign Sign

Child Neurology: Exaggerated dermal melanocytosis in a hypotonic infant

“…Extensive dermal melanocytosis, a distinguishing feature in our patient, is associated with several LySD, most frequently Hurler syndrome and GM1. 2,4 Given our patient's history and clinical presentation, including Brazilian heritage, MRI findings, and extensive dermal melanocytosis, GM1 was determined to be the most likely diagnosis. Targeted gene testing was sent, confirming a compound heterozygote mutation in the GLB1 gene of R59H and W527LfsX5.…”

“…This distinguishing feature has been increasingly recognized as a harbinger of GM1. [2][3][4][5] In rare disorders where expensive genetic testing and invasive procedures are often used to reach a diagnosis, recognition of unique clinical features on the physical examination can be a great asset.…”

“…There are now 54 reported cases of extensive dermal melanocytosis in children with LySD, with 17 occurring in GM1, 25 in Hurler syndrome, 9 in Hunter syndrome, 2 in a-mannosidosis, and 1 in NiemannPick disease. [2][3][4][5] Despite similar histology between typical dermal melanocytosis and those associated with LySD, the latter persist and even progress over time rather than fading.…”

“…This factor then binds to chemotactic melanocyte receptors, leading to abnormalities in melanocyte migration and producing the large dermal melanocytosis seen. 4 Clinical case: Part II. After her initial decline in development between 3 and 5 months of age, the patient's development remained stagnant through the present time, age 11 months.…”

Manchas Mongólicas Múltiplas e Sobrepostas numa Criança Caucasiana

“…Although traditionally regarded as benign, some publications suggested that extensive and multiple MS present at aberrant locations and persistent beyond early childhood may co-exist with inborn errors of metabolism. [2][3][4][5] The most common lysosomal storage disorders associated with MS are mucopolysaccharidosis type I (Hurler's disease) and GM1-gangliosidosis, and in a few cases mucopolysaccharidosis type 2 (Hunter's syndrome), mucolipidosis, Niemann-Pick disease and mannosidosis. [2][3][4][5][6][7] The pathogenic mechanisms behind this association are not completely understood but metabolites accumulated in inborn errors of metabolism seem to have an important role: they bind to a tyrosine kinase-type receptor and result in an abnormal activity of nerve growth factor, an important signal for transdermal melanocyte migration.…”