Apparently, genetic factors, especially in oligozoospermic and azoospermic patients, have been increasingly investigated in recent years. Genetic examination in infertility is important in terms of revealing the etiological factor and predicting the pregnancy potential, and the need for future counseling. Klinefelter syndrome (KS), known as 47XXY, can be seen in up to 10% of the cases with nonobstructive azoospermia and in one in 500-1000 live births [4]. Various variants of Klinefelter syndrome have been reported. Here, a case with a genetic diagnosis of 48XXYY, which is a very rare variant of Klinefelter syndrome, will be presented.
In the hormonal evaluation of the patient, levels of testosterone (1.74 ng/mL: 1.93-8.36 ng/mL), FSH (60.61 mIU/ mL: 0.7-11.1 mIU/mL), and LH (35.82 mIU/mL: 0.8-7.6 mIU/ mL) were as indicated. Other serum hormone levels were within normal limits. No pathological finding was detected in the pituitary parenchyma or sellar cavity in the MRI examination of the case. In scrotal ultrasonography, the dimensions of the left, and right testes were measured as 13x10x19 mm, and 11x18x10 mm, respectively. Millimetric calcification was observed in the upper pole of the right testis. Upon detection of azoospermia in the requested semen analysis, genetic analysis was performed. Genetic evaluation revealed the presence of a 48XXYY syndrome (Figure 1). Based on these findings, the patient was told that he had no fertility potential.
Figure 1: Analysis showing the 48,XXYY karyotype of the patient. GTG, G-banded karyotypes
The 48XXYY variant, which is seen in 2.3% of KS cases, was first reported by Muldal and Ockey in 1960 [8]. The 48,XXYY syndrome affects 1 in 18,000 to 50,000 male births. This syndrome is hypothesized to result from double nondisjunction during meiosis in spermatogenesis. In this syndrome, patients usually present to clinics with abdominal obesity, small testicles, learning difficulties, behavioral disorders, skeletal deformities, or delayed puberty [6,7]. The patient in this case report was sent to our clinic for infertility evaluation. In a study of 95 patients, the diagnosis of 48,XXYY syndrome had been made between the ages of 1-5 in 37%, between the ages of 6-10 in 25%, and at the age of ≥ 11 years in 27% of the cases [8]. Although the diagnosis is usually made in adolescence according to the findings mentioned above, prenatally diagnosed cases have been also reported [9,10]. It has been reported that only 30% of the cases are diagnosed based on the symptoms secondary to an endocrinological disorder [10,11].
The additional X and Y chromosomes lead to disorders of testicular dysgenesis and hypergonadotropic hypogonadism. Accordingly, this syndrome is characterized as azoospermia and small testicles as in our case. In the literature, testicular volumes between 1-4 mL have been detected in cases with this syndrome [11]. In these cases, testosterone insufficiency may cause gynecomastia and decrease in muscle mass. Our patient had gynecomastia. In one study, the incidence of gynecomastia was reported to be 25% in adolescents and 41% in adults [12]. Another remarkable finding in these cases is related to their body structures. In a clinical study, Borgaonkar et al., reviewed the reported data of 53 patients and concluded that 48,XXYY cases are taller starting from an earlier age, compared to the growth parameters of the general population as in our case [13]. In addition, cardiac, cerebral and pulmonary defects, recurrent respiratory tract infections, strabismus, neurological symptoms, or diabetes mellitus may occur [11,14]. According to these findings, 48,XXYY syndrome has been defined as a different clinical and genetic disorder by some researchers. In the literature, achievement of in vitro fertility has been reported in only one case with 48XXYY syndrome [15].
The 48XXYY syndrome is an extremely rare genetic disorder and should always be considered in the etiology of male infertility when evaluating azoospermic cases. When 48XXYY syndrome is detected, guidelines strictly recommend informing the patient and in case of need his relatives in detail regarding impossibility of spontaneous fertility.
Ethics Committee Approval: N / A.
Informed Consent: An informed consent was obtained from the patient.
Publication: The results of the study were not published in full or in part in form of abstracts.
Peer-review: Externally peer-reviewed.
Authorship Contributions: Any contribution was not made by any individual not listed as an author. Concept - H.Z., N.A.; Design - H.Z., N.A.; Supervision - F.E.; Resources - H.Z., N.A.; Materials - H.Z., N.A.; Data Collection and/or Processing - H.Z., N.A.; Analysis and/or Interpretation - H.Z., F.E., N.A.; Literature Search - H.Z., N.A.; Writing Manuscript - H.Z., N.A.; Critical Review - F.E.
Conflict of Interest: The authors declare that they have no conflict of interest.
Financial Disclosure: The authors declare that this study received no financial support.
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