Commensal microflora in human conjunctiva; characteristics of microflora in the patients with chronic ocular graft-versus-host disease.

PURPOSE: To investigate the transformation in the composition of ocular surface microflora. Evidence shows that microbial diversity correlates with autoimmune disorders. Chronic ocular graft-versus-host disease (GVHD) is the lethal complication after hematopoietic stem cell transplantation (HSCT) which influences patients' quality of life. It has a similar pathophysiology to autoimmune disorders but the relation of the microbial status especially in the ocular surface and chronic ocular GVHD is still unknown. METHODS: We prospectively harvested conjunctival microorganism with a cotton swab from following 3 groups, 32 eyes/20 ocular GVHD patients (9 males, 11 females), 28 eyes/20 nonGVHD cases (10 males, 10 females) which defined as post hematopoietic stem cell transplantation and without ocular GVHD, and 20 eyes/11 controls (7 males, 4 females). Conventional culture-based methods were performed to examine the microbial community. RESULTS: Ocular surface microbes in the GVHD patients was more complex in diversity compared with in the nonGVHD patients and the control. Staphylococcus species, Alpha-haemo Streptococcus, Corynebacterium species, Propionibacterium Acnes, Aerobic gram-positive cocci, Haemophilus Influenzae, and Aerobic gram-positive rod were observed in the GVHD patients, whereas only a few species detected in the other groups. CONCLUSIONS: We found that ocular surface microbes in the GVHD patients is more diverse than that in the nonGVHD patients and the controls. These results suggest the alternation of microbes are involved in the pathogenic process of the chronic ocular GVHD. Further examination using state-of-the-art methods will be needed to gain greater insights into the diversity of microflora on the chronic GVHD-affected ocular surface.

A novel and innovative paper-based analytical device for assessing tear lactoferrin of dry eye patients.

PURPOSE: To elucidate the correlation between lactoferrin concentration in the tear film and signs and symptoms of severe dry eye disease (DED) using a novel microfluidic paper-based analytical device (µPAD) and enzyme-linked immunosorbent assay (ELISA). METHODS: Twenty-four patients were recruited at the Keio University Hospital. Using a novel µPAD, lactoferrin concentrations were measured in 4 patients with GVHD-related DED, 3 patients with other types of DED and 2 controls (Group A). For validation by ELISA, 22 patients (7 patients from Group A) comprising 9 patients with GVHD-related DED, 6 patients with other types of DED and 7 controls were examined (Group B). The link between lactoferrin concentration and clinical data about the severity of aqueous tear deficient DED was also investigated by both µPAD and ELISA. RESULTS: The lactoferrin concentration in tear fluid of the DED patients was positively correlated between µPAD and ELISA (p = 0.006, r = 0.886). The tear fluid of the GVHD patients showed low or undetectable lactoferrin concentration. Analysis by ELISA demonstrated that lactoferrin concentrations in the tear film from the GVHD patients were significantly lower than those from the non-GVHD patients (p = 0.010576). ELISA revealed lactoferrin concentration correlated with the value of Schirmer test and tear film breakup time, whereas it was inversely correlated with OSDI, fluorescein and rose bengal scores. CONCLUSIONS: The novel µPAD may pave the way for measuring lactoferrin concentration in tear fluid from DED patients. Our results suggested that lactoferrin concentration in tear fluid reflect the severity of DED.