Familial Occurrence of Isolated Late-onset Nasolacrimal Duct Obstruction in Two Unrelated Families.

Late-onset nasolacrimal duct obstruction (NLDO) as a result of inflammatory processes causing dacryo-stenosis is a common entity affecting mostly women. While a few mechanisms have been suggested as contributors to the expression of NLDO, the trigger for the inflammation remains mostly unknown. Familial predilection for this condition has not been previously reported. We present two families with multiple individuals affected with congenital or late-onset NLDO, describe the signs and symptoms of the affected individuals, and explore their medical history for any contributing factors. Family A, spanning four generations, included 7 female patients affected by late-onset NLDO. Family B, spanning two generations, included 8 individuals affected by either congenital or late-onset NLDO. This case series suggests a familial predisposition to NLDO, apparently with an autosomal dominant inheritance pattern. Further studies are needed to elucidate the molecular basis of this genetic predisposition.

Partial penetrance and phenotypic variability of aplasia of lacrimal and salivary glands caused by a novel FGF10 donor splice-site mutation.

Thirteen affected individuals of six generations of a single kindred presented with epiphora evident from infancy. Physical exam and Schirmer test revealed variable expression of tear deficiency, congenital punctal atresia, and dry mouth with multiple caries, without concomitant abnormalities of the ears or digits, commensurate with a diagnosis of aplasia of the lacrimal and salivary glands (ALSG). Reconstruction of the upper lacrimal drainage system was performed in some of the affected individuals. Genetic analysis, testing six affected individuals and three non-affected family members, identified a single novel heterozygous splice-site variant, c.429 + 1, G > T in fibroblast growth factor 10 (FGF10) (NM_004465.1), segregating throughout the family as expected for dominant heredity. RT-PCR assays of HEK-293 cells transfected with wild type or mutant FGF10 demonstrated that the variant causes skipping of Exon 2. Notably, individuals sharing the same variant exhibited phenotypic variability, with unilateral or bilateral epiphora, as well as variable expression of dry mouth and caries. Moreover, one of the variant carriers had no ALSG-related clinical findings, demonstrating incomplete penetrance. While coding mutations in FGF10 are known to cause malformations in the nasolacrimal system, this is the second FGF10 splice-site variant and the first donor-site variant reported to cause ALSG. Thus, our study of a unique large kindred with multiple affected individuals heterozygous for the same FGF10 variant highlights intronic splice-site mutations and phenotypic variability/partial penetrance in ALSG.

Ocular manifestations among patients with congenital insensitivity to pain due to variants in PRDM12 and SCN9A genes.

Congenital insensitivity to pain (CIP) is a group of rare genetic disorders with a common characteristic of absent sensation to nociceptive pain. Here we present a series of six patients; three had a novel variant in the PRDM12 gene (group A), and three had a missense variant in the SCN9A gene (group B). We compared the ocular manifestations between the two groups. Records of these patients from 2009 through 2018 were reviewed. The retrieved data included demographics, genetic analysis results, ocular history and ophthalmic findings including visual acuity, corneal sensitivity, tear production, ocular surface findings, cycloplegic refraction, and fundoscopy. We found that patients with PRDM12 variant had more severe manifestations of ocular surface disease, with more prevalent corneal opacities and worse visual acuity, compared to patients with SCN9A variant.

Ocular manifestations of congenital insensitivity to pain: a long-term follow-up.

AIM: To describe ocular manifestations in children with congenital insensitivity to pain with and without anhidrosis (CIPA and CIP). METHODS: We reviewed records of eye examinations of 39 children diagnosed with CIPA or CIP. We collected clinical data, with particular attention to ocular surface findings. Corneal sensitivity was tested by presence of a blink reflex upon touching the cornea. Statistical analysis assessed differences in manifestations between the two conditions, and relationships among corneal sensitivity, presence of corneal opacities and visual acuity (VA). RESULTS: CIPA was diagnosed in 32 children and CIP in 7. The median follow-up periods were 50 months (CIPA group) and 94 months (CIP group). Corneal opacities were present in 23% of CIPA eyes and in 57% of CIP eyes. A blink reflex was positive in 52% of CIPA eyes and in 33% of CIP eyes. We recorded VA ≥20/25 in 36% of CIPA eyes, whereas all patients with CIP had VA ≤20/30. For the whole cohort, we found a negative correlation between a preserved blink reflex and the presence of corneal opacities, and a positive correlation between a preserved blink reflex and VA ≥20/25. CONCLUSION: Children with congenital insensitivity to pain are prone to develop corneal scarring. Patients with CIP tend to have more severe ocular surface disease than those with CIPA, probably due to more prevalent loss of corneal sensation. In both groups, a preserved blink reflex correlated with good vision. Affected children should have close follow-up to promptly treat ocular surface disease and prevent vision loss.