A case of a female newborn, followed up to the 9th month of life, presenting a clinical picture of multiple malformations, typical of trisomy-18, is reported by the AA.: microcephaly, low set of ears, micrognaty, ogival palate, superabunding skin in the neck, simian crease, typical hands attitude, luxation of the right hip, severe neurological symptomatology with the characteristic rigidity and, finally, an extremely severe mental defect.
Growth has always been very poor; death occurred at the 9th month of life.
Chromosome research, done with two cultures of capillary blood, revealed the presence of two lines of normal and trisomy-18 cells in similar percentage.
The literature concerning the subject is examined and discussed.