Large aberrant Mongolian spots coexisting with cutis marmorata telangiectatica congenita (phacomatosis pigmentovascularis type V or phacomatosis cesiomarmorata).

A 1-month-old boy showed cutis marmorata telangiectatica congenita (CMTC) involving a block-like pattern on his left leg and thigh and on the left side of his trunk, along with bilateral greyish-blue hyperpigmentation involving the buttocks and thighs and being in part intermingled with CMTC. This association of CMTC with Mongolian spots has been reported as a distinct type of phacomatosis pigmentovascularis (PPV), namely PPV type V. More recently, the term phacomatosis cesiomarmorata (cesius = blue) has been proposed. We believe phacomatosis cesiomarmorata is another example of twin spotting or didymosis.