Bilateral limbal stem cell disease in a patient with Addison’s disease

Abstract

© BMJ Publishing Group Limited 2021. No commercial reuse. See rights and permissions. Published by BMJ. DESCRIPTION A 43yearold female patient presented with blurring, pain and foreign body sensation for 18 months. Systemic history was significant for primary adrenocortical insufficiency (PAI) diagnosed 10 years ago following complaints of chronic fatigue and weight loss. She underwent highdose prednisolone therapy but discontinued medication 2 years ago. At presentation, she was already on topical lubricating eye drops for 3 months. Bestcorrected visual acuity (BCVA) was 6/60 in the right eye (OD) and 6/24 in the left eye (OS). Slitlamp examination showed bilateral conjunctival congestion, peripheral superficial corneal neovascularisation, superficial punctate keratitis, mild epithelial haze and whorled epithelial pattern (figure 1A,B). Schirmer II test values (at 5 min) were 10 mm in both eyes. The rest of the ocular examination was normal except for the presence of significant posterior subcataracts (OS>OD). A diagnosis of bilateral partial limbal stem cell deficiency (LSCD) secondary to Addison’s disease was made. Systemic evaluation revealed serum cortisone levels were low at 43.2 nmol/L (normal range: 83–359 nmol/L). Serum electrolytes, thyroid profile, parathormone levels and blood sugars were normal. Topical lubricants (hydroxypropyl methylcellulose 0.3% eye drops once every two hours, sodium hyaluronate 0.1% eye ointment) two times and tacrolimus (0.03% w/w) eye ointment at bedtime and a short course of topical steroids (loteprednol etabonate 0.5%) in a weekly tapering regimen were prescribed. Systemic hormonal replacement therapy was resumed by the endocrinologist. Over 3 months, there was significant improvement in her symptoms with resolution of LSCD (figure 2A,B). BCVA improved to 6/12 p in OD, and in OS it remained at 6/60 p due to cataract. The peripheral vascularisation and epithelial haze regressed, and residual corneal scarring was noted. The limbal stem cells are known to reside in the basal epithelium at the limbus and are responsible for the ocular surface integrity, acting as a mechanical barrier preventing conjunctival epithelial overgrowth over the cornea. Several disorders can lead to LSCD and its sequalae of scarring and chronic inflammation, eventually affecting the vision and patient comfort. Addison’s disease (primary adrenal insufficiency) occurs due to dysfunction of bilateral adrenal cortex manifesting as chronic fatigue, muscle weakness and gastrointestinal disturbances. Adrenal hormones also regulate the ocular surface health, inhibiting release of cytokines and chemokines that adversely affect limbal stem cells. Association of LSCD with polyendocrinopathy has been reported previously in literature. 5 However, those patients had coexisting diseases like idiopathic hypoparathyroidism and autoimmune polyendocrinopathy/candidiasis/ectodermal dystrophy syndrome. Our case is different from other cases reported previously; her ocular symptoms started after she discontinued her systemic hormonal therapy.