[Ocular manifestations of pseudoxanthoma elasticum]

[Pseudoxanthoma elasticum: A rare cause of gastrointestinal bleeding in children]

INTRODUCTION

Pseudoxanthoma elasticum (PXE) is a rare autosomal recessive connective tissue disorder, characterized by calcification and progressive fragmentation of elastic fibers. Gastrointestinal lesions are rare in children and may be responsible for serious complications. This article reports two pediatric cases of PXE revealed by gastrointestinal bleeding.

CASE REPORTS

An 11-year-old boy and a 12-year-old girl were hospitalized for gastrointestinal bleeding. Digestive endoscopy showed hemorrhagic gastroenteritis bulbitis in the first case and it was normal in the second. Abdominal ultrasound showed diffuse linear calcifications in both cases. The diagnosis of PXE was retained based on the presence of vascular disease in both patients, a skin lesion in the girl, and an ocular lesion in the boy. The genetic study confirmed the diagnosis of PXE identifying two ABCC6 mutations in the composite state in the boy: the c.2263G> A (p.G755R) mutation on exon 18 and the c.3421C> T (pR1141X) mutation on exon 24 and the 4021G> A (R1164Q) mutation in the homozygous state of ABCC6 exon 24 in the girl.

CONCLUSION

Digestive manifestations are unusual ; however, pseudoxanthoma elasticum should be considered in all cases of gastrointestinal bleeding for no apparent reason. Early diagnosis allows prevention and measures to control the risk factors and limit the progression of complications.

Visual Impairment in Pseudoxanthoma Elasticum: A Survey of 40 Patients

BACKGROUND

Pseudoxanthoma elasticum is an inherited disorder of connective tissue characterized, among other symptoms, by impaired vision.

OBJECTIVE

To evaluate the nature and age of onset of ophthalmologic manifestations in pseudoxanthoma elasticum.

PATIENTS AND METHODS

Forty consecutive patients affected with pseudoxanthoma elasticum underwent measurements of their refractive error and visual acuity, together with slit-lamp examination.

RESULTS

The mean age of the patients (8 M, 32 F) was 43.35 years. Fifty-seven eyes (33 patients, mean age: 40.75 years) had a BCVA >20/50 whereas 23 eyes in 16 patients (mean age: 53.31 years) had ≤20/50. Seven patients (17.50%), all but one over 52 years old, were visually disabled. BCVA ≤20/50 in at least one eye was observed in 73.33% of patients of 52 years old or older and in 20.00% of patients younger than 52, respectively. Angioid streaks were observed in 75 eyes (93.75%) and extended toward the macula in 51 eyes from 29 patients. Macular involvement was observed for the first time at a mean age of 44.28 years. Neovascularization was observed in 28 eyes (17 patients; mean age: 51.70 years), all with poor BCVA.

CONCLUSION

Macular choroidal neovascularization is frequent in pseudoxanthoma elasticum, and accounts for the poor ophthalmologic natural history of the disease. Patients should be advised to self-monitor their visual acuity using the Amsler grid. The frequency of choroidal neovascularization appears age-dependent, suggesting that bi-yearly fundus examination is appropriate in young patients whereas patients older than 40 should be examined twice a year.