Partial tetrasomy of chromosome 22q11.1 resulting from a supernumerary isodicentric marker chromosome in a boy with cat-eye syndrome

Congenital hypopituitarism and multiple midline defects in a newborn with non-familial Cat Eye syndrome

Background

Cat eye syndrome (CES) is a rare chromosomal disease, with estimated incidence of about 1 in 100,000 live newborns. The classic triad of iris coloboma, anorectal malformations, and auricular abnormalities is present in 40% of patients, and other congenital defects may also be observed. The typical associated cytogenetic anomaly relies on an extra chromosome, derived from an inverted duplication of short arm and proximal long arm of chromosome 22, resulting in partial trisomy or tetrasomy of such regions (inv dup 22pter-22q11.2).

Case presentation

We report on a full-term newborn, referred to us soon after birth. Physical examination showed facial dysmorphisms, including hypertelorism, down slanted palpebral fissures, and dysplastic ears with tragus hypoplasia and pre-auricular pit. Ophthalmologic evaluation and heart ultrasound identified left chorioretinal and iris coloboma and ostium secundum type atrial septal defect, respectively. Based on the suspicion of cat eye syndrome, a standard karyotype analysis was performed, and detected an extra small marker chromosome confirming the CES diagnosis. The chromosomal abnormality was then defined by array comparative genome hybridization (a-CGH, performed also in the parents), which identified the size of the rearrangement (3 Mb), and its de novo occurrence. Postnatally, our newborn presented with persistent hypoglycemia and cholestatic jaundice. Endocrine tests revealed congenital hypothyroidism, cortisol and growth hormone (GH) deficiencies, which were treated with replacement therapies (levotiroxine and hydrocortisone). Brain magnetic resonance imaging, later performed, showed aplasia of the anterior pituitary gland, agenesis of the stalk and ectopic neurohypophysis, confirming the congenital hypopituitarism diagnosis. She was discharged at 2 months of age, and included in a multidisciplinary follow-up. She currently is 7 months old and shows a severe global growth failure, and developmental delay. She started GH replacement treatment, and continues oral hydrocortisone, along with ursodeoxycholic acid and levothyroxine, allowing an adequate control of glycemic and thyroid profiles as well as of cholestasis.

Conclusions

CES phenotypic spectrum is wide and highly variable. Our report highlights how among the possible associated endocrine disorders, congenital hypopituitarism may occur, leading to persistent hypoglycemia and cholestasis. These patients should be promptly assessed for complete hormonal evaluations, in addition to major malformations and midline anomalies. Early recognition of such defects is necessary to decrease fatal events, as well as short and long-term related adverse outcomes.

Mosaic cat eye syndrome in a child with unilateral iris coloboma

BACKGROUND

Cat eye syndrome (CES) is a rare chromosomal disorder with a known incidence of 1 per 50,000-150,000 live newborns. The classic triad of iris coloboma, anorectal malformations, and auricular abnormalities is present in 40% of patients. In addition, other ocular malformations and systemic defects can be present. The aim of this report is to present a patient with unilateral iris coloboma related to a mosaicism of cat eye syndrome.

METHODS

A complete ophthalmological and systemic evaluation was performed in a three-year-old male. He also underwent a standard karyotype and FISH analysis with a probe against the 22q11.2 locus.

RESULTS

The ophthalmological and systemic evaluation revealed a unilateral iris coloboma and ipsilateral auricular malformations. Karyotype analysis of blood leukocytes indicated the presence of a marker chromosome in 6% of the analyzed cells. FISH analysis showed three positive signals in 5.5% of the analyzed nucleus.

CONCLUSION

This patient presented two of the three classic manifestations of CES; interestingly, they were unilateral. The 22q11 duplication was identified by standard karyotype and confirmed with FISH. The present case demonstrates the importance of conducting a multidisciplinary approach in patients with congenital malformations associated with known syndromes.

Rare otologic presentation of cat eye syndrome

We encountered an extremely rare case where a patient with cat eye syndrome (CES) who presented with symptoms of posterior semicircular canal dehiscence (PSCD). CES is a rare genetic disorder, resulting from duplication of chromosome 22. Patients may present with variable phenotypes, including characteristic of coloboma, heart defect, periauricular skin pit/tag, microtia, anal atresia and mildly retarded mental development in some cases. PSCD is also a disease of the inner ear, where patients present with third window signs and symptoms due to lack of bony coverage. PSCD is usually associated with a high riding jugular bulb and fibrous dysplasia. In this study, we report a new otologic finding in CES patient as an association of PSCD and high jugular pulp. We describe the work up and its findings and the management of this patient. SIMILAR CASES PUBLISHED:: None.

Typical and Atypical Associated Findings in a Group of 346 Patients with Mayer-Rokitansky-Kuester-Hauser Syndrome

STUDY OBJECTIVE

The Mayer-Rokitansky-Kuester-Hauser (MRKH) syndrome is characterized by vaginal and uterine aplasia in a 46,XX individual. Multiple abnormalities may be associated with MRKH syndrome, and it appears to overlap other syndromes. The aim of this study was to describe the spectrum of associated malformations and syndromes as well as abnormal karyotypic findings in a large cohort of 346 patients.

DESIGN, SETTING, AND PARTICIPANTS

The study is a retrospective analysis of 346 MRKH patients treated in the University Hospital in Tuebingen between 1998 and 2013.

MAIN OUTCOME MEASURES

The dataset was screened for typical associated malformations as well as atypical malformations and abnormal karyotypes. A complete review of the literature was included.

RESULTS

Among our cohort of 346 patients, we found that 53.2% had MRKH type 1, 41.3% had MRKH type 2, and 5.5% had MURCS syndrome. The group with associated malformations included 57.6% renal, 44.4% skeletal, and 30.8% other malformations. Additionally, we found 2 cases of absent radius syndrome, 3 cases of anal atresia, and 1 patient with oculodentodigital dysplasia, and other atypical malformations. Abnormal karyotypes were found in 5 cases, and 39 siblings and 11 parents had known malformations.

CONCLUSIONS

This study supports the hypothesis that the syndrome has a multifactorial pathogenesis. With the high numbers of associated malformations reported in this study, patients with MRKH syndrome should be regarded as having a complex syndrome. Molecular-genetic analyses in larger numbers of children after surrogacy, twin pregnancies, and familial cases may make it possible to obtain further information about the etiology of the syndrome.