The timely diagnosis of 49, XXXXY with the combined detection of MLPA, karyotype, and QF-PCR in a newborn with multiple congenital malformations: a case report

BACKGROUND: 49, XXXXY is a rare sex chromosomal aneuploidy syndrome. The patients usually are diagnosed several months or years after birth. Herein a neonate with respiratory distress and multiple malformations was diagnosed with 49, XXXXY syndrome by an economical method of multiplex ligation-dependent probe amplification (MLPA) followed karyotype analysis. CASE DESCRIPTION: An infant was born via spontaneous vaginal delivery at 41(+3) weeks’ gestation and hospitalized due to neonatal asphyxia. He was the first child to a 24-year-old gravida1, para1 (G1P1) mother. The newborn was characterized low birth weight (2.4 Kg, below the 3(rd) percentile), and an Apgar score of 6 at 1 minute, 8 at 5 minutes, and 9 at 10 minutes. The physical examinations of the patient revealed ocular hypertelorism, epicanthal folds, low nasal bridge, high-arched palate, cleft palate, micrognathia, low-set ears, microcephaly, hypotonia, and micropenis. Echocardiography revealed atrial septal defects (ASD). The brainstem auditory evoked potential (BAEP) reflected auditory function impairment. Genetic testing methods, including MLPA, karyotyping, and quantitative fluorescent polymerase chain reaction (QF-PCR), were performed for definitive diagnosis, which confirmed 49, XXXXY syndrome. CONCLUSIONS: The presentation of the 49, XXXXY newborn was atypical, they may only include low birth weight, multiple malformations and a characteristic facial appearance which were consistent with the characteristics of autosomal and sex chromosome aneuploidies. At this time, the economical and rapid method of MLPA to screen the number of chromosome, and then choose the appropriate means to make the final diagnosis and improve the quality of life of patients with timely therapy.