Visual loss secondary to eosinophilic mucin rhinosinusitis in a woman: a case report

INTRODUCTION: Eosinophilic mucin rhinosinusitis is an inflammatory pathological condition of the nose and paranasal sinuses. It is rare, occurs in immunocompetent patients and is characterised by peripheral eosinophilia and extensive bilateral sinus disease. To the best of our knowledge, visual loss with this condition has not been previously reported. CASE PRESENTATION: We present the case of a 26-year-old Asian woman with a background history of chronic sinusitis who presented with acute left-sided visual loss. Imaging showed significant opacification in the frontal, ethmoidal and sphenoidal sinuses as well as evidence of a unilateral optic neuritis. Histological analysis of sinus mucin revealed dense eosinophilic infiltrate and, despite medical and surgical intervention, vision was not restored in her left eye. CONCLUSION: We introduce visual loss as a complication of eosinophilic mucin rhinosinusitis. This adds further evidence to previous reports in the literature that optic neuropathy in sinusitis can occur secondary to non-compressive mechanisms. We also describe a rare finding: the vision in this patient did not improve following steroid therapy, antifungal therapy or surgical intervention. There are very few such cases described in the literature. We conclude that chronic sinusitis is an indolent inflammatory process which can cause visual loss and we reiterate the importance of recognizing and considering sinusitis as a cause of visual loss in patients in order that prompt medical and surgical treatment of the underlying disease can be initiated.