Chronic ocular sequelae in Stevens-Johnson syndrome: a genetic association study

Purpose: This study sought to investigate the association of molecular markers with chronic ocular sequelae in Ste-vens-Johnson syndrome/toxic epidermal necrolysis (SJS/TEN).Methods: One hundred SJS/TEN patients (200 eyes) with confirmed diagnosis were enrolled between July 2011 and July 2015 from a tertiary eye-care hospital, and their clinical histories were noted. Each eye was scored for severity of manifestation on a scale of 0-5. Peripheral blood samples were collected for DNA followed by screening for interleukins (IL-4, IL-13, IL-4R) polymorphisms, HLA-A locus allele typing, and sera to detect levels of the apoptotic markers granulysin and sFas L.Results: Of the 100 enrolled patients (53 males/47 females; age range: 6-58 years), the incriminating drugs were non-steroidal anti-inflammatory (52%), antibiotics (10%), sulphonamides (8%), anti-epileptics (6%), and unknown (24%). Significant differences in the frequencies of IL-4R polymorphism, HLA-A*3301, HLA-A*02, and HLA-A*2402 alleles, and elevated levels of granulysin and sFas L were observed in patients compared to controls. The ocular complications of conjunctival keratinization (p=0.004) showed an association with IL-13 promoter region (IL-13a) genotypes.Conclusions: The study highlights the possible association of interleukin-13 with severity-graded chronic sequelae and the role of HLA-A alleles-HLA-A*3301, HLA-A*02, and HLA-A*2402 in SJS/TEN causation and manifestation. Screening of these alleles may help caregivers to identify alleles associated with severe and lifelong ocular complications, and help in appropriate treatment and management of the condition.