Clinical and Reproductive Characteristics of Patients with Mixed Gonadal Dysgenesis (45,X/46, XY)

IntroductionMixed gonadal dysgenesis (MGD) or 45,X/46,XY mosaicism is a sex chromosomal disorder of sexual development. We aim to characterize the clinical and reproductive features of 45X/46 XY attending tertiary care center in Kerala.Materials and MethodRetrospective review of clinical records which include clinical presentation, hormonal profile, cytogenetics, psychosexual assessment, and histopathology of gonadectomy specimen of ten cases of 45X/46 XY mosaicism who attended Endocrinology/ OBG out patient department from 2008 to 2020.ResultsThe mean ages of all the cases were 12 ± 3.79 years (± 2 SD). Short stature was universally seen. Virilisation was the most common manifestation (80%) followed by delayed puberty (20%). Autoimmune thyroid disease was seen in 40% of cases. We noticed a delayed presentation in our clinical study. 45X/46 XY subjects who wished to continue as female underwent gonadectomy and were feminized with hormone replacement therapy. Male 45X/46 XY who retained their undescended testis is planned for periodic surveillance for malignancy.Conclusion45X/46 XY may present like Turner’s syndrome in clinical practice. Early counseling and gender assignment by a panel of specialists are crucial. Delayed presentation is less commonly encountered now a day and may pose a clinical challenge. Management in 45X/46 XY is multi-disciplinary which includes Turner’s like surveillance, proper sex assignment, timely genital reconstruction surgeries, gonadectomy, gonadal monitoring, and hormonal replacement therapy is needed.     

High-level mosaicism for 45,X in 45,X/46,XX at amniocentesis in a pregnancy with a favorable outcome and postnatal progressive decrease of the 45,X cell line

ObjectiveWe present prenatal diagnosis of high-level mosaicism for 45,X in 45,X/46,XX at amniocentesis in a pregnancy with a favorable outcome and postnatal progressive decrease of the 45,X cell line.Case reportA 32-year-old, gravida 2, para 1, woman underwent amniocentesis at 17 weeks of gestation because of the abnormal first-trimester maternal serum screening result indicating a 1/34 risk for Down syndrome. Amniocentesis revealed a karyotype of 45,X[27]/46,XX[15]. Simultaneous array comparative genomic hybridization (aCGH) on uncultured amniocytes revealed 12% mosaicism for monosomy X. Prenatal ultrasound was normal. The pregnancy was carried to term, and a 2780-g phenotypically normal female baby was delivered. The cord blood had a karyotype of 45,X[12]/46,XX[28]. At age one month, the peripheral blood had a karyotype of 45,X[13]/46,XX[27]. Interphase fluorescence in situ hybridization (FISH) analysis on the buccal mucosal cells revealed 2% (2/102 cells) mosaicism for monosomy X, compared with 1% (1/100 cells) in the normal control. When follow-up at age one year, she was doing well with normal physical and psychomotor development. Her body weight was 9.9 Kg (50th – 85th centile), and her body height was 75 cm (50th – 85th centile). The peripheral blood had a karyotype of 45,X[4]/46,XY[36].ConclusionHigh-level mosaicism for 45,X in 45,X/46,XX at amniocentesis can be associated with a favorable outcome and postnatal progressive decrease of the 45,X cell line.     

Detection of mosaicism for 46,X,i(Y) (q10) in the blood lymphocytes in a phenotypically normal male neonate with prenatally detected 45,X/46, XY at amniocentesis and cytogenetic discrepancy in various tissues

ObjectiveWe present detection of mosaicism for 46,X,i(Y) (q10) in the blood lymphocytes in a phenotypically normal male neonate with prenatally detected 45,X/46, XY at amniocentesis and cytogenetic discrepancy in various tissues.Case reportA 35-year-old, gravida 2, para 1, woman underwent amniocentesis at 17 weeks of gestation because of advanced maternal age. Amniocentesis revealed a karyotype of 45,X [8]/46,XY [15]. Simultaneous array comparative genomic hybridization (aCGH) on uncultured amniocytes revealed the result of arr (Y) × 0–1 with 25.493-Mb mosaic deletion of chromosome Yp11.31-q11.23. Prenatal ultrasound findings were unremarkable. The fetus had normal male external genitalia on fetal ultrasound. Following genetic counseling, the pregnancy was carried to 38 weeks of gestation, and a phenotypically normal male baby was delivered without any abnormalities of the male external genitalia. The cord blood had a karyotypes of 46,X,i(Y) (q10)[8]/45,X[3]/46,XY [29], and placenta had a karyotypes of 45,X [25]/46,X,i(Y) (q10)[7]/46,XY [8]. When follow-up at age two months, the neonate was normal in development. The peripheral blood had a karyotypes of 46,X,i(Y) (q10)[8]/45,X[5]/46,XY [27]. Interphase fluorescence in situ hybridization (FISH) analysis on 101 buccal mucosal cells showed normal X and Y signals in 101/101 cells.ConclusionFetuses with 45,X/46, XY at amniocentesis can be associated with mosaicism for 46,X,i(Y) (q10) in the blood lymphocytes, cytogenetic discrepancy in various tissues and a favorable outcome.     

High-level mosaicism for 45,X in 45,X/46, XY at amniocentesis in a pregnancy with a favorable fetal outcome and cytogenetic discrepancy in various tissues

ObjectiveWe present prenatal diagnosis of high-level mosaicism for 45,X by amniocentesis in a pregnancy with a favorable fetal outcome.Case reportA 35-year-old, gravida 2, para 1, woman underwent amniocentesis at 17 weeks of gestation because of advanced maternal age. Amniocentesis revealed a karyotype of 45,X[13]/46,XY[11]. Simultaneous array comparative genomic hybridization (aCGH) on uncultured amniocytes revealed the result of Yp11.3q11.21 × 0–1 [0.1], Yq11.21q11.23 × 0–1 [0.6]. At 19 weeks of gestation, she underwent the second amniocentesis which revealed a karyotype of 45,X[13]/46,XY[12], and aCGH and multiplex ligation-dependent probe amplification (MLPA) on uncultured amniocytes showed 37% mosaicism for Y-deleted cells. At 28 weeks of gestation, she underwent the third amniocentesis which revealed a karyotype of 45,X[25]/46,XY[25], and aCGH on uncultured amniocytes revealed the result of Yq11.21q11.23 × 0.5, Yq11.23q12 × 0.7. Interphase fluorescence in situ hybridization (FISH) analysis on uncultured amniocytes revealed that 16.67% (20/120 cells) were Y-deleted cells. The parental karyortypes and prenatal ultrasound were normal. At 37 weeks of gestation, a 2707-g phenotypically normal male baby was delivered with normal male external genitalia. The karyotypes of cord blood, umbilical cord and placenta were 45,X[25]/46,XY[15], 45,X[18]/46,XY[22] and 45,X[25]/46,XY[15], respectively. When follow-up at age five months, the neonate was normal in external genitalia and physical development. The peripheral blood had a karyotype of 45,X[29]/46,XY[11], and FISH analysis on 100 buccal mucosal cells showed no abnormal signals. When follow-up at age 11 months, the neonate was physically normal, and the peripheral blood had a karyotype of 45,X[17]/46,XY[23].ConclusionHigh-level mosaicism for 45,X in 45,X/46, XY at amniocentesis can be associated with a favorable fetal outcome despite the presence of cytogenetic discrepancy in various tissues.     

Fetal blood sampling demonstrating chimerism in monozygotic twins discordant for sex and tissue karyotype (46,XY and 45,X)

Fetal blood sampling has been used in the genetic work-up of twin gestations for rapid karyotyping. We present a case of twins which on ultrasound evaluation revealed hydrops fetalis in one twin and a normal second twin. Fetal blood sampling revealed the presence of mosaicism for 46,XY/45,X in both twins. HLA antigen testing showed the twins to be identical. The patient elected pregnancy termination. Blood chromosomal analysis after delivery revealed both twins to have 46,XY/45,X mosaicism, but the twin with signs of hydrops fetalis had tissue chromosomes of 45,X and the normal twin had tissue chromosomes of 46,XY. Amniotic fluid chromosomal analysis revealed 46,XY in twin A and 45,X in twin B. This represents a case of identical (monozygotic) twins with sex discordance. In this case, there was the probable occurrence of post-zygotic chromosomal non-disjunction leading to the discordancy of the sex in this set of twins. With the presence of vascular communication in monozygotic twins, there is the possibility of exchange of blood in monozygotic twins and the result of blood chimerism in twins.     

A Complete Gonadal Dysgenesis Case with Mental Retardation,Congenital Hip Dislocation,Severe Vertebra Rotoscoliosis,Pectus Excavatus,and Spina Bifida Occulta

Background46,XY, or Swyer syndrome, is a complete gonadal dysgenesis. Patients usually presents with primary amenorrhea with underdeveloped secondary sex characteristics. Phenotypes of these patients are female. In this report, a Swyer syndrome case is reported with novel clinical features that are classified as connective tissue disorders. This case and the 2 other previously reported Swyer syndrome cases with ascendant aortic aneurysm and diaphragmatic hernia are suggest that the Y chromosome has an important role in the structure of connective tissue.CaseHere we report a case of a 17-year-old with clinical features of 46,XY complete gonadal dysgenesis including external female genitalia, hypoplastic uterus, hypergonadotrophic hypogonadism, incomplete secondary sex characterics, primary amenorrhea, and normal male karyotype. In addition, she had mild mental retardation, severe rotoscoliosis, pectus excavatus, spina bifida occulta, hip dislocation, and long, slender extremities. She had a rudimentary uterus and streak gonads; after giving her cyclic estrogen and progesterone pills, she was able to menstruate.Summary and ConclusionIn this report, a Swyer syndrome case was discussed regarding clinical features, especially those are not characteristic for Swyer syndrome after a review of the literature.     

Differentiating Swyer Syndrome and Complete Androgen Insensitivity Syndrome: A Diagnostic Dilemma

BackgroundSwyer syndrome and complete androgen insensitivity syndrome are disorders of sex development in which patients present a female phenotype and 46,XY karyotype.CaseThe authors present a case report of an 18-year-old patient with primary amenorrhea and delayed puberty. The karyotype was 46,XY. No mutations of sex-determining region Y gene and androgen receptor genes were identified, and imaging methods failed to show müllerian structures. A diagnosis of complete androgen insensitivity syndrome was presumed, but after hormonal replacement therapy was started a “hidden” uterus developed, leading to the definite diagnosis of Swyer syndrome.Summary and ConclusionThe diagnosis of Swyer syndrome can be challenging, because visualization of müllerian structures is sometimes difficult and analysis of genetic mutations is not helpful in the majority of cases.     

Prenatal diagnosis of 45,X/46,XY mosaicism with cleft lip and epispadias

Introduction  

45,X/46,XY mosaicism is an uncommon chromosomal anomaly with a range of phenotypes from normal males to cases of multiple congenital anomalies.     

Adnexal Torsion Due to Borderline Mucinous Tumor of the Gonad in a Prepubertal Girl with Mixed Gonadal Dysgenesis (45,X/46,XY) and a Turner Phenotype

BackgroundTurner syndrome (TS) is a sex chromosome condition characterized by complete or partial loss of the X chromosome. Patients with mixed gonadal dysgenesis (45,X/46,XY) and a Turner phenotype are predisposed to gonadoblastoma with malignant transformation.CaseWe present the case of a TS patient with 45,X/46,XY with 2 episodes of left adnexal torsion (AT). Biopsies during detorsion showed benign mucinous cystadenoma. Pathology following bilateral gonadectomy revealed a left gonad with mucinous borderline tumor and right gonad with gonadoblastoma, both of which have malignant potential.Summary and ConclusionGonadectomy is recommended in XY gonadal dysgenesis to decrease risk of malignant transformation from gonadoblastoma. Although rare in pediatric patients, ovarian malignancies have been identified among AT cases. To our knowledge, we present the first case of AT due to borderline ovarian mucinous tumor of the ovary and contralateral gonadoblastoma in a patient with mixed gonadal dysgenesis (45,X/46,XY) and a Turner phenotype.     

The Dilemma of Sex of Rearing: A Case of a 45,X/46,XY Neonate with Hydrocolpos

Background

A rare disorder of sex development is 45,X/46,XY mosaicism, which is phenotypically very heterogenous, ranging from normal male (or female) to that of genital ambiguity of varying degrees.

Unravelling complex mosaicism of sex chromosomes in a patient with primary amenorrhea through cytogenetic analysis on urothelial cells

ObjectiveSex chromosome mosaicism remains challenging in the study of disorders of sex development (DSD). Aneuploid cells in the developing gonad play a major role in sex determination. Therefore, it is necessary acknowledge their presence by different methods. Our aim was to stand out the utility of urothelial cells for unravelling complex and hidden cell lines in DSD patients.Case reportHerein we report on a 19-year-old female with primary amenorrhea, short stature without ambiguous external genitalia. She had a 45,X/46, XY karyotype in leukocytes. Interphase FISH revealed hidden 45,X/47,XYY/47,XXY/46,XY/46, XX mosaicism in leukocytes and urothelial cells.ConclusionThese findings highlight the importance of investigating sex chromosome mosaicism in other tissues. Of particular interest in cases of DSD are the cells from the urinary epithelium, which may reflect the cell composition of the urogenital ridge, the analysis of these cells should be considered within the clinical assessment of DSD patients.     

Mosaic 45,X/46, XX at amniocentesis with high-level mosaicism for 45,X in a pregnancy with a favorable fetal outcome and postnatal decrease of the 45,X cell line

ObjectiveWe present mosaic 45,X/46, XX at amniocentesis with high-level mosaicism for 45,X in a pregnancy with a favorable fetal outcome and postnatal decrease of the 45,X cell line.Case reportA 20-year-old, primigravid woman underwent amniocentesis at 17 weeks of gestation because of the non-invasive prenatal testing (NIPT) result of −4.82 Z score in sex chromosome at 12 weeks of gestation suggestive of Turner syndrome in the fetus. Amniocentesis revealed a karyotype of 45,X [18]/46,XX [15], and simultaneous multiplex ligation-dependent probe amplification (MLPA) on the DNA extracted from uncultured amniocytes showed mosaic Turner syndrome. Prenatal ultrasound and parental karyotypes were normal. She was referred for genetic counseling at 24 weeks of gestation, and continuing pregnancy was encouraged. At 39 weeks of gestation, a 2550-g phenotypically normal female baby was delivered. The karyotypes of cord blood, umbilical cord and placenta were 45,X [24]/46,XX [16], 45,X [23]/46,XX [17] and 45,X [28]/46,X,del(X) (q23)[12], respectively. When follow-up at age two months, the neonate was phenotypically normal in development. The peripheral blood had a karyotypes of 45,X [16]/46,XX [24]. Interphase fluorescence in situ hybridization (FISH) analysis on 103 buccal mucosal cells showed normal disomy X signals in all cells.ConclusionHigh-level mosaicism for 45,X in 45,X/46, XX at amniocentesis can be associated with a favorable fetal outcome, cytogenetic discrepancy in various tissues, and postnatal decrease of the 45,X cell line.     

Swyer Syndrome: A Case of Dysgerminoma Solely within the Fallopian Tube

Background46XY pure gonadal dysgenesis (Swyer syndrome) is a rare disorder of sexual development. Patients have a 46XY karyotype, though phenotypically they appear female with normal external genitalia and vagina. Although patients exhibit normal Müllerian structures (uterus, fallopian tubes, and vagina), they possess a pair of bilateral undifferentiated gonad streaks. Delayed puberty and primary amenorrhea are the common presentations. There is an increased risk of developing tumors in the gonads and therefore a bilateral gonadectomy is recommended.CaseA 16-year-old girl who presented with primary amenorrhea was diagnosed with Swyer syndrome. She underwent prophylactic bilateral gonadectomy and salpingectomies. She was discovered to have no gonadal malignancy, conversely dysgerminoma solely within the fallopian tube.Summary and ConclusionBoth bilateral salpingectomies and bilateral gonadectomies should be recommended as the operation of choice in patients with Swyer Syndrome.     

Prenatal diagnosis of mosaicism for double aneuploidy of 47,XXY and trisomy 7 (48,XXY,+7) at amniocentesis in a pregnancy with a favorable outcome

ObjectiveWe present prenatal diagnosis of mosaicism for double aneuploidy of 47, XXY and trisomy 7 (48,XXY,+7) at amniocentesis in a pregnancy with a favorable outcome.Case reportA 33-year-old woman underwent amniocentesis at 17 weeks of gestation because of an increased risk for Down syndrome in maternal serum screening. Amniocentesis revealed a karyotype of 48,XXY,+7[8]/46,XY[16]. Simultaneous array comparative genomic hybridization (aCGH) analysis on uncultured amniocytes revealed the result of arr [GRCh37] (7) × 3 [0.54], (X) × 2 [0.52], (Y) × 1, compatible with trisomy 7 mosaicism and Klinefelter syndrome mosaicism. The parental karyotypes and prenatal ultrasound findings were normal. Repeat amniocentesis performed at 23 weeks of gestation revealed a karyotype of 48,XXY,+7[13]/46,XY[7]. Simultaneous molecular cytogenetic analyses on uncultured amniocytes revealed 30% mosaicism for 48,XXY,+7 by aCGH and 37% (37/100 cells) mosaicism for trisomy 7 and disomy X by interphase fluorescence in situ hybridization (FISH) analysis. Polymorphic DNA marker analysis excluded uniparental disomy (UPD) 7 and indicated a maternal origin of the chromosome aberration. The pregnancy was continued to 39 weeks of gestation, and a 3070-g healthy male baby was delivered. The cord blood had a karyotype of 46,XY, the umbilical cord had a karyotype of 48,XXY,+7[3]/46,XY[37], and the placenta had a karyotype of 48,XXY,+7. At age one month, the neonate was phenotypically normal, and interphase FISH analysis revealed 4.8% (5/105 cells) mosaicism on buccal mucosal cells and 8.9% (8/90 cells) mosaicism on urinary cells for trisomy 7 and disomy X, compared with 2% in normal control. Interphase FISH analysis on buccal mucosal cells at age two months revealed normal findings in 100/100 cells.ConclusionMosaic 48,XXY,+7 at amniocentesis without UPD 7 can be associated with a favorable fetal outcome. Cytogenetic discrepancy between cultured amniocytes and uncultured amniocytes may occur in mosaic 48,XXY,+7 at amniocentesis.     

Dysgerminoma in a Prepubertal Girl with Complete 46XY Gonadal Dysgenesis: Case Report and Review of the Literature

BackgroundComplete 46XY gonadal dysgenesis (Swyer syndrome) is a rare and challenging diagnosis among prepubertal girls, as estrogen insufficiency becomes evident only during adolescence, with nonspecific symptoms such as primary amenorrhea and/or delayed puberty. Unfortunately, girls with Swyer syndrome are at high risk for malignancies in the dysgenetic gonads, which can be prevented only by performing prophylactic bilateral gonadectomy.CaseWe present a 9-year-old patient with Swyer syndrome diagnosed with dysgerminoma in the right gonad and gonadoblastoma in the left gonad after prophylactic bilateral gonadectomy.Summary and ConclusionConcerning the high risk of early gonadoblastoma and its malignant transformation, we recommend performing prophylactic bilateral gonadectomy at the time of diagnosis, even if the patient is prepubertal.     

Prenatal diagnosis of 45,X/46,XY mosaicism in a fetus with asymmetric gonadal dysgenesis

An 18 week abortus had been prenatally diagnosed as a 45,X/46,XY mosaic. The fetus was a phenotypic male with glandular hypospadias, a horseshoe kidney and asymmetric gonadal dysgenesis. This case represents a rare instance of prenatally diagnosed 45,X/46,XY mosaicism with an abnormal phenotype.     

Atypical Presentation of Swyer Syndrome

BackgroundSwyer syndrome is a rare type of disorder of sex development and typically presents with delayed puberty and primary amenorrhea. We describe an unusual presentation of this condition.CaseA 17-year-old female patient with typical thelarche and adrenarche presented with primary amenorrhea. Pelvic ultrasound showed normally developed uterus and bilateral ovoid hypoechoic structures suggestive of gonads. Laboratory investigations revealed highly elevated gonadotrophins with estradiol level within a range typical for a female of reproductive age and chromosome analysis showed a 46,XY karyotype. Histopathological examination of the gonadectomy specimens revealed gonadoblastoma and dysgerminoma with no functional ovarian or testicular tissue.Summary and ConclusionThis report reminds us the possibility of diagnosis of Swyer syndrome in the presence of normal pubertal development and normal sex steroid levels considered to be produced by gonadoblastoma.     

Hypoplastic Uterus and Clitoris Enlargement in Swyer Syndrome

BackgroundSwyer syndrome is associated with absent testicular differentiation in a 46XY phenotypic female.CaseA 17-year-old female presented with primary amenorrhea and 46XY karyotype. Breast and pubic hair development were Tanner 2, and clitoral enlargement was noted. Magnetic resonance imaging revealed a hypoplastic uterus and 2 “normal ovaries.” Serum follicle-stimulating hormone and luteinizing hormone were elevated. Testosterone and androstenedione were in the female range. Dehydroepiandrosterone sulfate was slightly elevated. Laparoscopic bilateral gonadectomy was performed. Pathology reports showed bilateral microscopic benign hilar cell tumors.Summary and ConclusionThe diagnosis was a real puzzle for the clinicians because of the association of clitoral hypertrophy without hirsutism, female internal genitalia, and a 46XY karyotype. Clitoral enlargement can be explained by transient androgen secretion by the hilar cells found in the resected gonads.     

Novel mutation of MAP3K1 gene in 46,XY DSD with complete gonadal dysgenesis

ObjectiveSwyer syndrome, or 46, XY complete gonadal dysgenesis, is a disorder of human sexual development which present with female external genitalia, lack of female reproductive organs, and a 46, XY karyotype. Many genes that participate in human sexual development have been implicated in the pathogenesis of 46, XY gonadal dysgenesis.Case reportA 18-year-old phenotypically female was presented with primary amenorrhea. Surveillance revealed hypergonadotropic hypogonadism, a normal male 46, XY karyotype and absent of functional gonad, which was confirmed by pathological examination of the streak gonad. Whole exome sequencing showed germline mutations of a novel missense variant, c.570G > C, p.Lys190Asn, in exon 2 of MAP3K1 gene.ConclusionGiven evolutionary conservation of lysine residue at position 190, the amino acid substitution may interfere with interaction between MAP3K1 and RHOA, and contributes to complete gonadal dysgenesis in the context of 46,XY.