Mosaic trisomy 22: Reaching the diagnosis through the skin

A girl aged 3 years was referred to the dermatology clinic for assessment of hyperpigmented lesions with a blaschkoid distribution in the upper extremity.She presented with facial dysmorphic features, including epicanthal folds, a low nasal bridge, and low-set ears, in addition to short stature (below the 3rd percentile), right-sided hemihyperplasia, clinodactyly of the fifth finger and hypoplastic nails (Fig. 1).During pregnancy, chromosomal array analysis of a chorionic villus sample had detected an aneuploidy of chromosome 22; this finding was not confirmed by amniocentesis, and the postnatal karyotype was normal.