[Glaucoma with aniridia and isolated congenital glaucoma in siblings: contribution and limits of genetics]

INTRODUCTION

Congenital glaucoma associated with aniridia and primary congenital glaucoma are regarded as different entities. Indeed, the abnormalities of the angle's structures as well as the genes involved are different. We report the observation of two sisters presenting these two types of glaucoma with particular attention paid to the importance and the difficulty of genetic counseling.

OBSERVATIONS

Child L, with no particular family history, had presented bilateral aniridia complicated by bilateral glaucoma since birth. In addition to medical and surgical treatment, general and genetic investigations were undertaken that revealed no abnormalities. No microdeletion of the gene PAX6 responsible for the aniridia was found. Consequently, the genetic advice was in favor of a second pregnancy for this couple. At birth, L's sister also presented bilateral congenital glaucoma, which was isolated, without aniridia. New genetic investigations were carried out but no abnormalities in PAX6, nor in FOXC1 or PITX2 involved in the development of the anterior chamber, were found. Moreover, the haplotypes for aniridia locus AN2 inherited by the two sisters were different, proof that this gene could not be responsible for the glaucoma.

DISCUSSION

At L's birth, the hypothesis retained was that she was a sporadic case whose gene mutation could not be identified (which happens in 50% of sporadic cases). The risk for the second pregnancy was negligible, although not null. The primary congenital glaucoma presented by L's sister remains unexplained in the context of aniridia and the role of the PAX6 gene was eliminated. The study of PITX2 and FOXC1 genes involved in anterior segment dysgenesis proved that they were also not involved. Thus, this observation evokes the responsibility of a gene other than PAX6 in aniridia, which could also have a role in isolated congenital glaucoma.

CONCLUSION

Analysis of congenital pathologies from a more genetic than clinical point of view seems to progressively break down the barriers established between the various phenotypes of hereditary congenital anomalies. Even if the association of aniridia and primary congenital glaucoma in siblings is reported here for the first time, it does not appear so extraordinary if one considers the complexity of the anterior chamber's development, which involves many genes, most of them still unidentified to date.

[Necrotizing fasciitis of the eyelids and orbit: a life-threatening ophthalmological emergency]

INTRODUCTION

Necrotizing fasciitis is an extremely serious exceptional infectious process affecting subcutaneous soft tissues with skin gangrene and vascular thromboses. Starting from a case repat of necrotizing fasciitis of the eyelids and orbit, which occurred in a child of 4, we analyse the early diagnostic elements and the urgency of treatment of a pathology which can rapidly be life-threatening.

OBSERVATION

A child, aged 4 presented a necrotizing fasciitis of the eyelid and orbit with serious toxic shock, after minor skin abrasion.

RESULT

Resuscitation and parenteral antibiotic therapy were not sufficient to stop the necrotizing process, which required surgical debridement of gangrenous tissues.

DISCUSSION

Necrotizing fasciitis is a rare affection with fatal local and general prognosis. Location on the orbit and eyelids is extremely rare, with only a score of cases recorded in the literature, principally in adults. Our observation shows the possibility of occurrence in a young child and found the typical features of the pathology: minor initial trauma, beta hemolytic streptococcus, extremely fast progression requiring resuscitation, extensive antibiotic therapy and surgical excision of the gangrenous tissues. Eyesight remained intact, but cases of blindness have been described in the literature. Secondary reconstructive surgery on the eyelids may be necessary.

CONCLUSION

Urgent diagnosis of this exceptional pathology that may affect the young child and prompt antibiotic therapy and surgical debridement are the only guarantees of survival of infected patients.