Authors :
María Camila Rueda-Rodríguez, MD – Universidad Nacional de Colombia
David Eduardo Malaver, MD – Universidad Nacional de Colombia
Angélica María Uscátegui-Daccarett, MD, MSc – Universidad Nacional de Colombia
Juan José Yunis-Londoño, MD, MSc – Universidad Nacional de Colombia
Presenting Author: Jorge Luis Ramírez-Molina, – Universidad Nacional de Colombia
Rationale:
Measurement of Human Leukocyte Antigens (HLA) in patients with epilepsy has demonstrated to be a cost beneficial strategy to avoid complications at the start of antiseizure medication (ASM). Other countries had found that their population have HLA variants that predict adverse cutaneous reactions to ASMs. It is needed to establish if this marker exists in the Colombian population with the aim of acquire it as a rutinary measurement. This study intends to find the most frequent HLA-A and B variant in Colombian patients with epilepsy with adverse cutaneous reactions to ASMs.
Methods:
Ambispective case-control study. Convenience sampling was performed, with venous blood samples taken from patients with epilepsy receiving ASMs, with and without a history of adverse cutaneous reaction. HLA-A and B haplotype typing was performed in a specialized laboratory. Patients previously provided their informed consent, and if applicable, informed assent to participate in the study and for blood sampling. HLA-A and HLA-B loci typing (intermediate resolution) was performed by PCR amplification followed by liquid-phase hybridization using reagents from Immucor Lifecodes (Werfen) on a Luminex 200 platform in a laboratory accredited by the European Federation for Immunogenetics (EFI). Allele assignment was performed using Immucor's MatchIt DNA platform. Allele frequencies for both the A and B loci were estimated by direct counting. Allele frequencies were compared using row and column contingency tables. Similarly, for some alleles, those with a higher frequency of occurrence, Fisher's t test (2x2 table) was performed to confirm these findings
Results:
A total of 29 cases and 29 controls of varying ages were recruited. Regarding adverse cutaneous reactions, nonspecific rashes occurred in 79% of cases, Stevens-Johnson syndrome in 10%, and other rashes in 11%, 48% of which were mild. The most common medication causing these reactions was carbamazepine. Chi-square analysis found no statistically significant differences between patients and controls for either the HLA-A allele (p=0.325) or the HLA-B allele (p=0.12).
Conclusions:
No HLA-A or HLA-B variant was found in the Colombian population that would predict the presence of adverse cutaneous reactions to antiseizure medications. This result may be related to the mixed race of this population, which limits the availability of pure HLA alleles.
Funding:
This study was approved by the Ethics Commitee of the Universidad Nacional de Colombia and funded by the Research Direction -Bogotá of the Universidad Nacional de Colombia Code HERMES 51283