( Trisomy 13 syndrome ) [Abstract] Trisomy 13 syndrome (trisomy l3 syndrome) is a group of syndromes characterized by multiple malformations such as small skull, scalp defects, small eyes, cleft palate, etc. Lu Xuemei, Department of Otolaryngology, Liaocheng People’s Hospital [Alias] D1trisomy syndrome; 13-15 trisomy syndrome; Bartholin-Patau syndrome. [Etiology] An increase of one chromosome during meiosis due to the non-disjunction of chromosome 13. [Clinical manifestations] Craniomaxillofacial and oral malformations: small skull, scalp defect, low sloping forehead; small or no eye, wide orbital spacing, hypoplasia of cornea, iris, retina; external ear malformation, deafness; cleft palate, bilateral cleft lip, small lower jaw, etc. Other systemic anomalies: right-sided heart, ventricular septal and atrial septal defects, arteriovenous catheterization; cryptorchidism, bicornuate uterus; polydactyly, fingers (toes) fixed in flexion, etc. [Diagnosis] Diagnosis was made based on the characteristics of multiple malformations. Dermatoglyphics showing through hands and chromosomal examination showing karyotype 47, XX, +13 or 47, XY, +13 can confirm the diagnosis. It should be differentiated from the following disorders: (1) partial trisomysyndrome of chromosome 13: duplication of the segment from the end of the short arm to band 4 of region 1 of the long arm of chromosome 13 (pto-q14), manifested by microcephaly, convex forehead, hypotrichosis, small jaw, small mouth deformity, flexion of the little finger, and impaired consciousness and movement. Children may live into childhood. (2) Chromosome 13 partial trisomy syndrome (13q partial trisomy syndrome): duplication of the long arm of chromosome 13 (q14→qter), manifesting as small head, narrow forehead, small eyeballs, both eyebrows connected, low ears, abnormal tooth eruption, cleft lip, cleft palate, and polydactyly. Children may also survive into childhood. [Treatment] Symptomatic support. [Prognosis] Poor, almost all (>95%) die within 3 years of age.