Mistaken uveitis diagnosis

A highly malignant but rare form of lymphoma can be mistakenly diagnosed as uveitis, representing a major diagnostic and therapeutic challenge, the Irish College of Ophthalmologists 2018 Annual Conference heard. Prof Conor Murphy MD PhD, Professor of Ophthalmology, RCSI, discussed primary intraocular lymphoma, a very rare intraocular malignancy that masquerades as autoimmune uveitis. This form of lymphoma represents a significant diagnostic challenge, as it requires cytological analysis of ocular fluid samples of limited size and cellularity, he explained. A lack of prospective studies to identify optimum therapy adds further complexity to this disease, which frequently spreads to the central nervous system (CNS) giving it a poor long-term prognosis, which is not helped by delays in diagnosis, he said. Notable neurological symptoms include behavioural and cognitive changes and a contrast MRI should be carried out, he said. Once correctly diagnosed a key management goal is eradication of the reservoir of malignant ocular cells that can lead to fatal CNS dissemination, and to preserve vision. Treatment options include orbital and ocular radiotherapy, intravitreal methotrexate or rituximab and high-dose methotrexate or chemotherapy with autologous stem cell transplantation. Efficacy versus toxicity must be carefully considered and multidisciplinary team management of this disease is vital, “although contrasting views exist even amongst experts”, Prof Murphy noted. ORAL STEROIDS The conference’s uveitis session was chaired by Mr Dara Kilmartin MD, immediate past Honorary Secretary of the International Uveitis Study Group, who highlighted the latest management approaches to the disease. “We’ve been using oral steroids now for over 60 years and they are the main way of controlling sight-threatening uveitis. For about 30 years we’ve been using systemic immunosuppressive therapy (IST) of all classes,” Mr Kilmartin stated. He said there has been a move from using cyclosporine to tacrolimus, while intravitreal IST like methotrexate or sirolimus are promising, but there is a fear of alkylating agents due to their DNA-altering effects, and they are used in a stepladder approach to minimise the side-effects. As IST can have significant toxic side-effects it is hoped that the advent of biologic therapies and more targeted treatment will mean less risk for patients, though real-world efficacy and cost are current issues. Local intravitreal therapy has many advantages, including rapid and targeted delivery and avoids systemic side-effects, but is restricted to uniocular disease or marked asymmetry, which is uncommon, Mr Kilmartin noted. He also highlighted the value of therapeutic vitrectomy, particular in paediatric patients, for suitable uveitis cases.