Journal of Pediatric Ophthalmology and Strabismus

Visual Impairment in a Case of Juvenile Paget's Disease With Pseudoxanthoma Elasticum: An Eleven Year Follow Up

Khaled W Sharif, FRCS(Glasg); William W Doig, FRCS; Frank P Kinsella, MRCPI, FRCS(Glasg)

Abstract

ABSTRACT

An 11-year follow-up of a child presenting with Pagets disease of bone, and who subsequently developed pseudoxanthoma elasticum, is described. The influence of therapy on the ocular manifestations was disappointing. Calcitonin did not prevent the occurrence or progression of angioid streaks, and Argon laser photocoagulation of complicating subretinal neovascular membranes failed to prevent visual loss.

Abstract

ABSTRACT

An 11-year follow-up of a child presenting with Pagets disease of bone, and who subsequently developed pseudoxanthoma elasticum, is described. The influence of therapy on the ocular manifestations was disappointing. Calcitonin did not prevent the occurrence or progression of angioid streaks, and Argon laser photocoagulation of complicating subretinal neovascular membranes failed to prevent visual loss.

INTRODUCTION

The beneficial response of the skeletal problems in a case of juvenile Paget's disease of bone treated with human calcitonin was reported in 1977 by Woodhouse et al. We now present an 11-year follow-up of this patient, with particular reference to the ophthalmological features which developed, and their response to treatment.

Case Report

Our patient, a male Scottish child, had from the age of 18 months onwards sustained several spontaneously occurring long bone fractures with ensuing deformity. Because of biochemical and radiological features suggestive of Paget's disease, a transiliac trephine bone biopsy was undertaken when the child was five years old and this confirmed a diagnosis of juvenile Paget's disease of bone. Treatment with intramuscular human calcitonin was instituted, resulting in good clinical, biochemical and radiological improvement in the patients condition.1

In 1977, when our patient was 10 years old, he developed cutaneous (Figure 1) and histological evidence of pseudoxanthoma elasticum and was referred to our department for ophthalmological assessment. On initial evaluation he was asymptomatic and visual acuity was found to be 6/6 bilaterally. Anterior segment examination and intraocular tension were normal bilaterally, but fundoscopy revealed the presence of several angioid streaks in the right posterior pole. The left fundus was normal at this stage.

FIGURE 1: "Xanthomatous" thickening of the skin associated with laxity and telangectasia involving the neck, antecubital fossa, and popliteal fossa, paraumbilical area (1977).

FIGURE 1: "Xanthomatous" thickening of the skin associated with laxity and telangectasia involving the neck, antecubital fossa, and popliteal fossa, paraumbilical area (1977).

FIGURE 2: Right fundus photograph showing numerous angioid streaks (1979).

FIGURE 2: Right fundus photograph showing numerous angioid streaks (1979).

FIGURE 3A: Left fundus photograph demonstrating numerous retinal hemorrhages surrounding the optic disc.

FIGURE 3A: Left fundus photograph demonstrating numerous retinal hemorrhages surrounding the optic disc.

FIGURE 3B: Fluorescein angiogram of left eye revealing a subretinal neovascular membrane related to an angioid streak inferonasal to the fovea.

FIGURE 3B: Fluorescein angiogram of left eye revealing a subretinal neovascular membrane related to an angioid streak inferonasal to the fovea.

Over the succeeding 2 years, vision remained normal but numerous angioid streaks developed affecting both posterior poles, being especially marked on the right side (Figure 2). At this stage our patient was advised to avoid contact sports.

In 1980, following minor blunt trauma, vision in his left eye suddenly fell to hand movement level. Examination of the left eye revealed multiple subretinal hemorrhages in the posterior pole (Figure 3A). Fluorescein angiography demonstrated that the underlying cause was a subretinal neovascular membrane related to an angioid streak located inferonasal to the fovea (Figure 3B). Following partial resolution of perifoveal hemorrhage, vision in the left eye improved to 6/18. At this stage argon laser photocoagulation to the subretinal neovascular membrane was carried out. This attempt to arrest progression of the neovascular membrane proved unsuccessful. Several months later, a fibrotic macular scar had reduced vision in this eye to counting fingers level (Figures 4A and 4B). At this stage, vision in the right eye was 6/6, but examination noted an increase in both number and width of angioid streaks in the posterior pole of this eye.

In 1981, however, visual acuity in the right eye dropped to 6/36 because of the development of parafoveal hemorrhages. As with the left eye, fluorescein angiography demonstrated that the source of hemorrhage was a subretinal neovascular membrane related to a parafoveal angioid streak (Figures 5A and 5B). Because the patient's fellow eye had shown such a poor response to photocoagulation, it was decided to withhold laser therapy in the right eye. This conservative approach has proved quite successful over the past 7 years with the patient's visual acuity fluctuating between 6/18 to 6/36 due to recurrent episodes of subretinal hemorrhage occurring both spontaneously or related to minor ocular trauma.

FIGURE 4A: Left fundal photograph of macular scar 6 months following laser treatment.

FIGURE 4A: Left fundal photograph of macular scar 6 months following laser treatment.

FIGURE 4B: Fluorescein angiogram of left macula.

FIGURE 4B: Fluorescein angiogram of left macula.

FIGURES 5A AND 5B: Fundal photograph and fluorescein angiogram revealing a parafoveal subretinal neovascular membrane in the right eye.

FIGURES 5A AND 5B: Fundal photograph and fluorescein angiogram revealing a parafoveal subretinal neovascular membrane in the right eye.

Our patient continues to receive daily calcitonin therapy (currently as a nasal spray) which has prevented further bony fractures and stopped gross bony deformity occurring. At present he is six feet in stature and merely exhibits mild bony deformity (Figure 6). To date, he has not suffered any systemic complications of his pseudoxanthoma elasticum.

DISCUSSION

"Juvenile Paget's disease", a term first used by Choremis in 1958,2 describes a rare condition which occurs in early life characterized by bony fragility and deformity with elevated levels of serum alkaline and acid phosphatase, as well as elevated urinary hydroxyproline levels. We add our report to the very few previously documented cases of the ocular manifestations of Paget's disease of bone presenting during childhood.3

The association of pseudoxanthoma elasticum with juvenile Paget's disease of bone has previously been described,4 and lends support to the hypothesis that both conditions are variable presentations of a common hereditary disorder involving widespread abnormal collagen formation.5

FIGURE 6: Recent photograph of our patient (1988) demonstrates mild bony deformity; some skull enlargement, kyphosis and anterior bowing of both femurs is present.

FIGURE 6: Recent photograph of our patient (1988) demonstrates mild bony deformity; some skull enlargement, kyphosis and anterior bowing of both femurs is present.

Angioid streaks occur in 15% of patients with Paget's disease of bone.6 Failure of argon laser photocoagulation to halt progression of the subretinal neovascular membrane in our patient, is in keeping with the disappointing results of other workers treating subretinal neovascularization complicating angioid streaks.7 Possible explanations for the poor results include incomplete ablation of these subretinal neovascular membranes due to their perifoveal location,8 or that laser treatment was actually stimulating further neovascularization.9

Calcitonin therapy was instituted at a very early age in our patient, and it is noteworthy that while severe bony disease was prevented, no beneficial influence on the ocular involvement occurred. The role that our patient's pseudoxanthoma elasticum played in the ocular manifestations is unknown. It remains speculative that calcitonin may have prevented ocular problems had our patient suffered from Paget's disease alone.

CONCLUSION

An 11-year ocular follow-up of a boy who presented with juvenile Paget's disease of bone and who subsequently developed pseudoxanthoma elasticum showed progressive bilateral deterioration in vision due to the occurrence of angioid streaks complicated by subretinal neovascular membrane formation. Treatment with calcitonin did not prevent angioid streak formation, and Argon laser photocoagulation failed to cause regression of the associated subretinal neovascular membranes.

REFERENCES

1. Woodhouse NJY, Fisher MT, Sigurdsson G, Goplin JS, Macintyre I, et al. Pagets disease in a five year old: Acute response to human calcitonin. Br Med J. 1972; 4: 267-269.

2. Choremis C, Yannakos D, Papadutos C, Barouteu E. Osteitis deformans in an 11-year-old boy. HeIv Paediatrica Acta. 1958, 13:85.

3. Walsh FB. Clinical Neurophthalmology, second edition, Williams and Wilkins, Baltimore, MD, 1957, ? 701.

4. Woodcook CW. Pseudoxanthoma elasticum, angioid streaks of retina and osteitis deformans. Arcft Dermatol. 1952; 65:623.

5. Hamdy RC. Rigets Disease Of Bone. Praeger Publishers, New York, NY, 1981. ? 17.

6. Tferry TL. Angioid streaks and osteitis deformans. Transactions of the American Ophthalmological and Otolaryngological Society. 1934. 32: 555-573.

7. Deutman AF, Kovacs B. Argon laser treatment in complications of angioid streaks. Am J Ophthalmol. 1979. 12:88.

8. Shilling JS, Blach RK Prognosis and therapy of angioid streaks. Transactions of the Ophthalmological Society (UK). 1975; 95:301.

9. Wilkinson CP. Stimulation of subretinal neovascularization. Am J Ophthalmol. 1975; 79:997.

10.3928/0191-3913-19891101-13

Sign up to receive

Journal E-contents