Letter to Editor: "Unusual Association of 45,X/46,XY Mosaic Turner Syndrome and Müllerian Agenesis".
Dear Editor, We would like to offer some recommendations regarding the recently published article “Unusual Association of 46XY/45XO Mosaic Turner Syndrome and Mullerian Agenesis,” by Ibekwe et al.[1] While this case report is undoubtedly exceptional, we noticed some minor errors and omissions. First, according to the International System for Human Cytogenomic Nomenclature, it is inappropriate to denote a karyotype as 45XO, because there is no “O” chromosome. Furthermore, when an X monosomic line is present in a mosaic, it should be indicated first: 45,X/46,XY. Note the use of commas between the number and the sex chromosomes. The 45,X/46,XY karyotype can present a wide range of phenotypes, including mixed gonadal dysgenesis and Turner syndrome (TS), as well as seemingly normal females and males. The specific phenotype depends on the distribution of cell lines among different tissues and organs.[2] Thus, while the authors argue for the coexistence of two conditions, this clinical presentation could be an alternative manifestation of the 45,X/46,XY karyotype. Moreover, the assertion “The absence of the uterus and ovaries means that the patient has a high chance of being infertile and amenorrheic” is unnecessary, since the patient is already amenorrheic, and infertility is obvious. Since the uterus and ovaries were not detected, a human chorionic gonadotropin stimulation test could be considered to evaluate the testosterone levels after stimulation, looking for active testicular tissue. If the result is positive, inform the patient that women with a 45,X/46,XY karyotype and testicular tissue are at high risk for malignancy. On the other hand, this article contains inaccurate citations. For example, the authors state that: “There are rare studies that have reported an association between karyotype 45X and MRKH. This rare association of the two syndromes has been described in 25 published case reports[15]” (Plevraki et al., Fertil Steril 2004;81(3):689–692). However, this reference does not address the issue, since Plevraki et al. analyzed six patients with MRKH who had a normal karyotype. Reference[16] is also cited out of context. This case undoubtedly presented a karyotype associated with TS. However, aside from short stature, sexual infantilism, and primary amenorrhea, the patient does not exhibit the typical features of this syndrome (webbed neck, low hairline at the base of the neck, low-set ears, broad chest with widely spaced nipples, cardiac anomalies, and cubitus valgus). Therefore, this could be a different clinical condition. It should be noted, however, that cases of classical TS [45,X] with an absence of the uterus and ovaries, resembling Müllerian agenesis, have been documented.[3–5] Therefore, accurately diagnosing patients with a 45,X/46,XY karyotype is challenging. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.
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