A Rare Case of a Male Infant with Down-Turner Syndrome and Review of Cases

@#Individuals with double aneuploidy of Down-Turner syndrome are very rare and to date, fewer than 50 cases have been reported, worlwide. We report a case of a male infant who presented with dysmorphic features of upslanting eyes, flat nasal bridge, wide spaced nipples and macroglossia. Based on the clinical features, he was diagnosed with Down syndrome. His peripheral blood sample was taken and sent for cytogenetic analysis for confirmation. Chromosome analysis of his lymphocyte cell culture revealed a mosaic pattern of double aneuploidy with monosomy X identified in 31 metaphases and trisomy 21 in 14 metaphases: (45,X[31]/47,XY,+21[14]). Further analysis with fluorescence in situ hybridization (FISH) using Vysis LSI SRY Spectrum Orange/CEP X Spectrum Green Probe and Vysis CEP Y Spectrum Aqua Probe and Vysis LSI 21 Spectrum Orange Probe performed on the cells (nuclei and metaphases) has confirmed the presence of the abnormal two cell lines (81% monosomy X and 19% trisomy 21) in the patient. Ultrasound investigations of his pelvic region showed normal testes and no evidence of uterus, ovary or vagina. To the best of our knowledge, this is the first Down-Turner syndrome reported in Malaysia. In conclusion, this case demonstrates the importance of Giemsa-banded karyotype and FISH analyses as diagnostic tools in identifying the chromosomal abnormality and determining the ratio of the normal:abnormal cells present in the patient. An annotated bibliography of earlier reported cases of Down-Turner with documented karyotyping is also included in this report.

Down-Turner Syndrome (45,X/47,XY,+21): Case Report and Review / 대한진단검사의학회지

We report the case of a 3-yr-old boy with Down-Turner mosaicism and review the previous reports of Down-Turner syndrome with documented karyotyping and clinical features. The patient showed clinical features of Down syndrome without significant stigma of Turner syndrome. Cytogenetic analysis of peripheral blood preparations by using G-banding revealed mosaicism with 2 cell lines (45,X[29]/47,XY,+21[4]). FISH analysis revealed that 87.5% of the cells had monosomy X karyotype and 12.5% of the cells had XY karyotype; trisomy 21 was only detected in the Y-positive cells. We suggest that additional cells should be analyzed and molecular genetic studies should be conducted to rule out double aneuploidy when karyotypes with sex chromosome aneuploidies and mosaicism are encountered, as in our case of Down syndrome mosaic with sex chromosome aneuploidy.

A Case of Down-Turner Syndrome / 대한소아내분비학회지

Down-Turner syndrome is a rare disease with the incidence of 1 in 2 million. Although Down syndrome with various Turner's karyotype were reported occasionally since a report in 1962, it was not reported in Korea. We experienced a case of Down-Turner syndrome with 47, X, del(X)(p11.2), +21/ 47, XX, +21, who has clinical features of Down syndrome such as hypotonia, weak Moro reflex, round and wide face, flat occiput, epicanthal folds, upward slanting of the palpebral fissures, low set ears, a simian line on both palms and the brachydactyly of the right little finger with the appearance of Turner syndrome such as the edema of hands, webbed neck. We think it will be necessary to follow up the patient in regard to the aspects such as infertility, sexual infantilism, and primary amenorrhea.