Angioid streaks and systemic disease

MULTIMODAL IMAGING OF ANGIOID STREAKS ASSOCIATED WITH TURNER SYNDROME

PURPOSE

To report multimodal imaging in a novel case of angioid streaks in a patient with Turner syndrome with 10-year follow-up.

METHODS

Case report of a patient with Turner syndrome and angioid streaks followed at Bellevue Hospital Eye Clinic from 2007 to 2017. Fundus photography, fluorescein angiography, and optical coherence tomography angiography were obtained.

RESULTS

Angioid streaks with choroidal neovascularization were noted in this patient with Turner syndrome without other systemic conditions previously correlated with angioid streaks.

CONCLUSION

We report a case of angioid streaks with choroidal neovascularization in a patient with Turner syndrome. We demonstrate that angioid streaks, previously associated with pseudoxanthoma elasticum, Ehlers-Danlos syndrome, Paget disease of bone, and hemoglobinopathies, may also be associated with Turner syndrome, and may continue to develop choroidal neovascularization, suggesting the need for careful ophthalmic examination in these patients.

Angioid streaks in sickle-thalassemia

Angioid streaks have been described in a diverse group of diseases including hemoglobinopathies such as sickle cell anemia and beta-thalassemia. We investigated the prevalence of angioid streaks and pseudoxanthoma elasticum in the rare situation of patients who had compound heterozygous traits for hemoglobin S and beta-thalassemia. We examined 58 consecutive patients with sickle-thalassemia. Of these, 25 were men and 33 were women, and they ranged in age from 19 to 58 years (mean, 32.6 years). Angioid streaks were identified in six of 58 patients (10%), and of these three also displayed the cutaneous lesions of pseudoxanthoma elasticum, which were confirmed by skin biopsy. An expanded study on several relatives of the patients with angioid streaks failed to identify any similar cases. Statistical evaluation of the main hematologic and biochemical parameters in the patients with and without angioid streaks did not demonstrate any significant differences, except that the thalassemic component in all six patients with angioid streaks was beta(0) (that is, did not allow the synthesis of hemoglobin A). We conclude that angioid streaks and pseudoxanthoma elasticum skin lesions occur with an increased frequency in patients with sickle-thalassemia.

The blood-retinal barrier in angioid streaks

The blood retinal barrier was investigated in a group of patients with angioid streaks and pseudoxanthoma elasticum, using the technique of vitreous fluorophotometry. Angioid streaks are breaks in the elastic layer of Bruch's membrane with atrophy of the adjacent pigment epithelium. The retinal pigment epithelial cells and their intercellular junctions form part of the blood retinal barrier. In this study, it was found that despite the presence of angioid streaks and extensive areas of pigment epithelial atrophy the blood retinal barrier was intact. In contrast, when disciform degeneration had occurred the blood retinal barrier was abnormal. It is proposed that vitreous fluorophotometry could be used to identify those patients developing disciform degeneration at an early and therefore potentially treatable stage.

Collagen maturation defects in Ehlers-Danlos keratopathy

Ehlers-Danlos syndrome is one of many inherited abnormalities of connective tissue, specifically collagen. A 16-year-old caucasian female with Type VI Ehlers-Danlos syndrome had five unusual corneal findings, four of which have not been reported in association with Ehlers-Danlos syndrome: micro-cornea (previously reported), cornea plana, keratoconus posticus, stromal haze at the level of Bowman's layer and a peripheral ring opacity suggestive of anterior embryotoxon. Type VI Ehlers-Danlos syndrome is associated with deficient activity of lysyl hydroxylase which ultimately is responsible for cross-linking collagen chains, the source of its tensile strength. Genetic regulation of procollagen formation is believed to be mediated by mRNA. Aggregation and maturation in the extracellular matrix is probably influenced and mediated by its evolving biochemical environment, particularly by complex carbohydrate moieties. An understanding of collagen maturation, and the pathophysiologic and biophysical consequences of abnormalities at this level of biochemical organization, permits more specific understanding of ocular dysmorphology and collagen diseases.

Mitral valve prolapse in sickle cell disease: manifestation of a generalized connective tissue disorder

Previous studies have shown an association of sickle cell disease with generalized connective tissue disorders such as pseudoxanthoma elasticum. We recently documented an unexpectedly high prevalence of mitral valve prolapse, a connective tissue disorder, in sickle cell disease. To investigate this association, skin biopsies were analyzed from 32 sickle cell disease patients, 11 of whom had mitral prolapse. Total and type III collagen, collagen solubility, and uronic acid were not different between the patients with or without mitral prolapse (p greater than 0.05). Computerized morphometric quantitation of the volume fraction of elastic fibers was greater in sickle cell disease patients than in 10 normals (3.1 +/- 0.1 mean +/- SEM vs 2.0 +/- 0.3%; p less than 0.01) but less than in three patients with pseudoxanthoma elasticum (9.7 +/- 0.6%; p less than 0.001). Desmosine radioimmunoassay (an index of elastic fibers) was greater in sickle cell disease patients with mitral prolapse than those without (239.3 +/- 9.3 vs 171.7 +/- 25.4 ng/mg wet weight; p less than 0.02). Histopathologic grading showed a similar trend (p = 0.07). The combined probabilities of these three independent tests of elastic fiber quantity showed an increased elastic fiber concentration in mitral prolapse patients compared to those without mitral prolapse (p less than 0.02). Thus, there is no evidence for a specific collagen defect; rather, sickle cell disease appears to be associated with a spectrum of elastic tissue disorders, a feature that could predispose to mitral valve prolapse.

The mucocutaneous marker of pseudoxanthoma elasticum

A patient with angioid streaks discovered ophthalmoscopically was evaluated in the dermatology clinic for pseudoxanthoma elasticum (PXE). Cutaneous markers for PXE did not appear in the usual locations; mucosal involvement of the lower lip was the only clinically ascertainable clue. The presence of the disease was confirmed by histologic examination of the oral mucosa. This case stresses the importance of familiarity with the mucocutaneous markers of PXE by members of the dental profession.

The significance of fluorescein angiography in the early diagnosis of lesions on ocular fundus at pseudoxanthoma elasticum patients

The role of fluorescein angiography in early diagnosis of lesions on fundus of the eye at pseudoxanthoma elasticum patients has been shown. The authors show angiographic changes on the basis of three cases of pseudoxanthoma elasticum patients.