Dry Eye and Ocular Surface Disease in Chronic Graft-Versus-Host Disease (GVHD) Patients

Dry eye is a multi-factorial disease that is frequently encountered in ophthalmological practice. Common dry eye symptoms include eye irritation, heaviness of the eyelids, blurred vision and light sensitivity (1). The worldwide prevalence of dry eye is generally high (2-4). In Asia, dry eye may affect up to 22% of adults above 40 years in China (5) and Japan (3). In Asian patients older than 65 years, prevalence rates of dry eye can be as high as 80% if diagnosis is based on abnormal tear stability, or as high as 60% on meibomian gland dysfunction (MGD), a major cause of tear instability (6).

Most dry eye patients can be successfully managed with lubricants, punctal occlusion, steroid and/or cyclosporine eye drops. However, some patients with severe dry eye and likely underlying diseases for example Graft-Versus-Host Disease (GVHD), who have exhausted conventional treatments may amount to 10-20 cases a year and are difficult to manage. These patients and their physicians are helpless when faced with these scenarios.

Hematopoietic stem cell transplantation (SCT) has been established as a potential curative therapy for hematologic malignancies (9). The number of SCT recipients has increased exponentially worldwide over the past 2 decades. GVHD is the major cause of morbidity and mortality in patients undergoing allogeneic SCT (10).

Dry eye associated with chronic GVHD is one of the major late complications after allogeneic SCT; it has a significant impact on patients' quality of life (11-13) and can lead to blindness (14). The immunological process of dry eye associated with chronic GVHD remains largely unknown but is believed to be traditional alloreactivity to recipient tissues.

The investigators propose to collaborate with Singapore General Hospital, Department of Haematology to focus on the clinical characteristics and immunological profile of the ocular surface inflammation in more severe chronic GVHD patients. Dry eye severity is more severe in chronic GVHD patients at SNEC, compared to idiopathic cases of dry eye. This may be due to referral bias, or may be related to the systemic disease. As such, the investigators intend to do a pilot study to define some ocular characteristics of non-referred haematology patients with GVHD. The investigators propose to screen and recruit 30 suitable participants who have chronic GVHD. Tests to be performed will include ocular imaging (Oculus K5M), ocular immunological profile (conjunctiva immune cells) and ocular surface inflammation (MMP-9 tear marker).