Background & objectives: Eales' disease is an idiopathic disease resulting in retinal neovascularization, recurrent haemorrhages, with or without retinal detachment predominantly affecting healthy young males (97.
Eales' disease is an idiopathic disease with retinal perivasculitis predominantly affecting the peripheral retina during the inflammatory stage followed by sclerosis of the retinal veins and retinal ischaemia and finally, retinal or optic disk neovascularization, recurrent haemorrhages, with or without retinal detachment (1).
Patients: Patients included in this study were those clinically diagnosed as Eales' disease by the criteria described by Das et al (1) and non-Eales' patients with non-infective diseases such as proliferative diabetic retinopathy, retinal detachment and proliferative vitreoretinopathy as controls.
Of these, 20 were from patients clinically diagnosed as Eales' disease and 13 others were from non-Eales' patients Group Ia.
Nine VFs from patients clinically diagnosed as Eales' disease and 10 VFs from non Eales' patients with non-infectious diseases stored at -20[degrees]C in L & T Microbiology Research Centre laboratory, Sankara Nethralaya, Chennai, during the period 1999-2003 were also included in this study Group Ib.
Group II (Prospective study)--Vitreous fluids and peripheral blood: Ten VFs from consecutive patients clinically diagnosed as Eales' disease and 23 VFs from non-Eales' patients as controls were included during February 2005 to December 2005.
Extraction of DNA from paraffin sections of ERM: Tissue sections of ERMs from Eales' disease and non-Eales' disease patients obtained from ocular pathology laboratory were used for this purpose.
Statistical analysis: The statistical analysis of data was done by [chi square] test for comparing the results of PCR on ERM, VF and blood of Eales' disease and control patients of Group Ia, Ib and II individually and all the results combined together.
Group I a: Of the 20 Eales' disease ERMs, 14 (70 %) were positive by PCR for one or more of the mycobacteria tested.
Group II--Prospective study: All VFs from 10 Eales' disease patients were negative by smear, two were positive by PCR, one each for M.
The aetiopathogenesis of Eales' disease is not clearly understood because of lack of appropriate specimens for microbiologic and histopathologic study (8).