First Report of Mexican Patients with PACS1-Related Neurodevelopmental Disorder and Review of the PACS1-, PACS2-, and WDR37-Related Ophthalmological Manifestations

Introduction

PACS1-related neurodevelopmental disorder (PACS1-related NDD) is caused by pathogenic variants in the PACS1 gene and is characterized by a distinctive facial appearance, intellectual disability, speech delay, seizures, feeding difficulties, cryptorchidism, hernias, and structural anomalies of the brain, heart, eye, and kidney. There is a marked facial resemblance and a common multisystem affectation with patients carrying pathogenic variants in the WDR37 and PACS2 genes, although they vary in terms of severity and eye involvement.

Case Presentation

Here, we describe 4 individuals with PACS1-related NDD from Mexico, all of them carrying a de novo PACS1 variant c.607C>T; p.(Arg203Trp) identified by exome sequencing. In addition to eye colobomata, this report identified corneal leukoma, cataracts, and tortuosity of retinal vessels as ophthalmic manifestations not previously reported in patients with PACS1-related NDD.

Discussion

We reviewed the ocular phenotypes reported in 74 individuals with PACS1-related NDD and the overlaps with WDR37- and PACS2-related syndromes. We found that the 3 syndromes have in common the presence of colobomata, ptosis, nystagmus, strabismus, and refractive errors, whereas microphthalmia, microcornea, and Peters anomaly are found only among individuals with PACS1-related NDD and WDR37 syndrome, being more severe in the latter. This supports the previous statement that the so-called WDR37-PACS1-PACS2 axis might have an important role in ocular development and also that the specific ocular findings could be useful in the clinical differentiation between these related syndromes.

Postnatal Serum Insulin-Like Growth Factor I and Retinopathy of Prematurity in Latin American Infants

PURPOSE

Identifying at-risk infants for retinopathy of prematurity (ROP) is complex in countries with emerging economies as infants that lack conventional risk factors, such as low birth weight (BW) and young gestational age (GA), still go on to develop severe ROP. Potential biomarkers, like serum insulin-like growth factor 1 (IGF-1) and slow postnatal weight gain, have been identified as good predictors for ROP in developed countries. We sought to determine the relationship between IGF-1 levels and ROP in two Latin American countries where the burden of disease is still significant.

METHODS

Prospective cohort study of infants in Guadalajara, Mexico and La Plata, Argentina. Filter-paper bloodspot IGF-1 assays were performed weekly from birth until hospital discharge or 40 weeks' postmenstrual age (PMA).

RESULTS

112 infants were studied with a median BW of 1412 g (range 620 g-2390 g) and a median GA of 33 weeks (range 25-37). There was no significant difference in IGF-1 between infants who developed ROP and those who did not.

CONCLUSION

Low IGF-1 was not associated with ROP in these infants. The lack of an association between ROP and IGF-1 in Latin America supports the observation that growth-based predictive models do not perform as well in this setting where more mature babies still develop severe ROP.

Ring chromosome 6 in a child with anterior segment dysgenesis and review of its overlap with other FOXC1 deletion phenotypes

Here, we report a patient with ring chromosome 6 [r(6)], associated with anterior segment dysgenesis (ASD) and other anomalies. The phenotype was due to a 1880 kb microdeletion at 6p25.3 identified by whole-genome array analysis, and was mainly attributable to a FOXC1 haploinsufficiency. Currently 37 patients with r(6) have been reported. We found that facial dysmorphism, ASD, heart anomalies, brain anomalies, and hearing loss are constant features only in severe cases of r(6), mainly related to hemizygosity of FOXC1. Thus, overlaps with other FOXC1 related phenotypes, such as the 6p25 deletion syndrome, Axenfeld-Rieger syndrome type 3, and ASD type 3. Contrarily, those patients whose r(6) does not disrupt FOXC1, have mild or moderate phenotypes and do not exhibit ASD.

Oxygen Monitoring Reduces the Risk for Retinopathy of Prematurity in a Mexican Population

BACKGROUND

Retinopathy of prematurity (ROP), a potentially blinding disease, affects preterm infants. High levels of oxygen saturation are a well-known risk factor for ROP.

OBJECTIVES

To assess the frequency of ROP type 1 needing treatment after improved oxygen monitoring (2011) in a Mexican preterm population selected for WINROP analyses and to retrospectively revalidate WINROP, an online surveillance system identifying infants at risk of developing ROP type 1.

METHODS

Preterm infants born with birth weight (BW) <1,750 g and/or at gestational age (GA) ≤34 weeks, screened for ROP in 2012-2014 at the Hospital Civil de Guadalajara, Mexico were included (n = 151). Eighty-five infants with GA <32 weeks qualified for WINROP analyses. GA, BW, maximal ROP stage, ROP treatment and weekly weights were recorded. The results in the present study were compared to those of a previous WINROP study in the same hospital (2005-2010; n = 352).

RESULTS

In the present WINROP cohort, 11.8% of the infants born at GA <32 weeks received treatment compared to 51.0% of the infants in the previous WINROP cohort. One infant (3%) born at GA ≥32 weeks received treatment during the present study period compared to 35.6% during the previous period. WINROP displayed 80.0% sensitivity in infants born at GA <32 weeks in the present study compared to 84.7% in the previous study.

CONCLUSIONS

Uncontrolled oxygen supplementation is the major risk factor for severe ROP in infants born at GA ≥32 weeks. After improved oxygen monitoring, the frequency of ROP treatment was dramatically reduced at the Hospital Civil de Guadalajara, Mexico.

[National survey of blindness and avoidable visual impairment in Argentina, 2013]

OBJECTIVE

Determine the prevalence of blindness and avoidable visual impairment in Argentina, its causes, the coverage of cataract surgery, and the barriers that hinder access to these services.

METHODS

Cross-sectional population study conducted between May and November 2013 using the standard methodology for rapid assessment of avoidable blindness (RAAB), with a random cluster sampling of 50 people aged 50 years or more, -representative of the entire country. Participants' visual acuity (VA) was measured and the lens and posterior pole were examined by direct ophthalmoscopy. An assessment was made of the causes of having VA < 20/60, the coverage and quality of cataract surgery, and the barriers to accessing treatment.

RESULTS

3 770 people were assessed (92.0% of the projected number). The prevalence of blindness was 0.7% (confidence interval of 95%: 0.4-1.0%). Unoperated cataract was the main cause of blindness and severe visual impairment (44.0% and 71.1%, respectively), while the main cause of moderate visual impairment was uncorrected refractive errors (77.8%). Coverage of cataract surgery was of 97.1%, and 82.0% of operated eyes achieved VA ≥ 20/60. The main barriers to receiving this treatment were fear of the surgical procedure or of a poor result (34.9%), the cost (30.2%), and not having access to the treatment (16.3%).

CONCLUSIONS

There is a low prevalence of blindness in the studied population and cataract is the main cause of blindness and severe visual impairment. Efforts should continue to extend coverage of cataract surgery, enhance preoperative evaluation, improve calculations of the intraocular lenses that patients need, and correct post-operative refractive errors with greater precision.

Prediction of retinopathy of prematurity using the screening algorithm WINROP in a Mexican population of preterm infants

OBJECTIVE

To retrospectively validate the WINROP (weight, insulin-like growth factor I, neonatal, retinopathy of prematurity [ROP]) algorithm in identification of type 1 ROP in a Mexican population of preterm infants.

METHODS

In infants admitted to the neonatal intensive care unit at Hospital Civil de Guadalajara from 2005 to 2010, weight measurements had been recorded once weekly for 192 very preterm infants (gestational age [GA] <32 weeks) and for 160 moderately preterm infants (GA ≥32 weeks). Repeated eye examinations had been performed and maximal ROP stage had been recorded. Data are part of a case-control database for severe ROP risk factors.

RESULTS

Type 1 ROP was found in 51.0% of very preterm and 35.6% of moderately preterm infants. The WINROP algorithm correctly identified type 1 ROP in 84.7% of very preterm infants but in only 5.3% of moderately preterm infants. For infants with GA less than 32 weeks, the specificity was 26.6%, and for those with GA 32 weeks or more, it was 88.3%.

CONCLUSIONS

In this Mexican population of preterm infants, WINROP detected type 1 ROP early in 84.7% of very preterm infants and correctly identified 26.6% of infants who did not develop type 1 ROP. Uncertainties in dating of pregnancies and differences in postnatal conditions may be factors explaining the different outcomes of WINROP in this population.

New ocular findings in two sisters with Yunis-Varón syndrome and literature review

The Yunis-Varón syndrome (YVS) represents a rare autosomal recessive syndrome of easy recognition characterized by cleidocraneal dysplasia, absence of thumbs and halluces, distal aphalangia, ectodermal anomalies, and poor outcome. Here, we report two sisters with YVS who also had papillo-macular atrophic chorioretinopathy with "salt-and-pepper" appearance that could not be attributed to environmental or metabolic causes. Our best hypothesis is that the ocular findings in our two patients are part of the phenotypic manifestations of YVS. We suggest that an extensive ophthalmologic examination should be carried out in all children with YVS in order to define the frequency and nature of the ocular findings in these patients.

[Results of a survey on organ donation and transplantation in the metropolitan area of Guadalajara, Mexico]

OBJECTIVE

To evaluate knowledge of and disposition towards organ and tissue donation for transplantation among the adult population of metropolitan Guadalajara, Jalisco, Mexico.

MATERIAL AND METHODS

A survey was conducted by personal interview with street-recruited persons over 18 years of age using a 29-item questionnaire. Metropolitan Guadalajara was divided into four municipalities and a proportional number of interviews was assigned to each one based on number of inhabitants, socio-economic stratum, age and gender.

RESULTS

Four hundred individuals were interviewed. Approximately 80% knew about organ donation and 65% knew that it was legal; however, only 24% had discussed the topic with their relatives. Seventy-one percent did not know how to donate organs and only 25% knew about organ donor cards. On the other hand, 66% were willing to donate, 16.5% would not donate and 17% were undecided. Bodily mutilation was the main reason (40%) given to not donate. 89% would authorize organ donation from a deceased relative, assuming the relative had previously expressed the desire to donate; on the contrary, only 29% would give such an authorization without their relative's prior consent. Finally, 65% considered the driver's license an adequate mean to express their desire to donate and 50% considered the information the mass media disseminated on the subject to be insufficient.

CONCLUSIONS

The majority of the metropolitan Guadalajara population knew about organ donation and would be willing to donate their organs. However, a high percentage did not know how to donate and considered the information disseminated on the subject insufficient. An on-going mass media campaign could resolve this matter and hopefully increase organ donation among this population.