Homozygous mutation in ABCA4 associated with cone rod dystrophy in a patient with Turner syndrome.

PURPOSE: We report a special case of a patient who presented with two rare genetic diseases, Turner syndrome and cone-rod dystrophy (CRD), caused by mutation in the ABCA4 gene. METHODS: We present a case of a 12-year-old female with a progressive visual loss, poor night vision and short stature. We performed a clinical, karyotype of peripheral blood and molecular genetic study. DNA sample from the index patient was subjected to whole exome sequencing. Variants localized in homozygous regions were validated by Sanger sequencing. RESULTS: Fundus examination presented CRD phenotype and the general examination revealed short stature, aortic coarctation and infantile uterus, without visible ovaries on pelvic ultrasound. The karyotype of peripheral blood showed monosomy 45,X. We identified a known homozygous deletion c.[885delC];[885delC] in ABCA4, resulting in a frameshift at the position p.[L296Cfs*4];[ L296Cfs*4] . In addition, mutations in RPGR and ORF15 were excluded. CONCLUSIONS: Several ocular disorders are known to be associated with Turner syndrome, however, in this case, we hypothesize that CRD is not related to Turner syndrome but may be a manifestation of the lack of a normal X chromosome with ABCA4 mutation.

Indications and results of exotropia surgical management.

AIM: To study the clinical particularities and the surgical management of the different forms of exotropia, and to analyze the prognostic factors influencing the surgical result. METHODS: Medical records of 132 patients who underwent exotropia surgery from 1995 to 2015, were retrospectively reviewed. Ophthalmological examination and a complete sensorimotor assessment were performed for each patient. All surgeries were performed by the same surgeon. RESULTS: We had 57 cases of intermittent exotropia (IE), 22 cases of infantile exotropia (IfE), 43 cases of sensory exotropia (SE) and 10 cases of concecutive exotropia (CE). The average age of onset of exotropia was 6.8 years +/- 8 SD. Amblyopia was noted in 36.4% of cases  of  IfE.  The mean deviation angle was  36.5  DP in (IE),  39.6  DP in (IfE)  and  44.5  DP  in  (SE). A vertical syndrome was frequently found in (IfE) patients. Bilateral recession of  lateral  rectus  was  the  most  performed  surgery  type.  The overall success rate after a  single  surgery  was  72%.  A multivariate logistic regression analysis  showed  that good prognosis  factors  were  the absence  of  amblyopia, the intermittent form of the strabismus,  a low  preoperative deviation angle and the ocular alignment on day one postoperatively. CONCLUSIONS: IE is the most common divergent strabismus.  Surgery resulted in successful alignment in most of the cases.  Early management and rigorous analysis of  patients sensorimotor status are the best guarantors of long-term success.