Clinical Abacavir Hypersensitivity Reaction among Children in India

Area of Science:

• Pediatric infectious diseases
• Clinical pharmacology
• Pharmacogenomics

Background:

• Abacavir is a key component of first-line antiretroviral therapy recommended by the National AIDS Control Organization.
• Abacavir hypersensitivity reaction (HSR) is a significant concern in patients receiving this medication.
• Understanding the incidence and characteristics of HSR in pediatric populations is crucial for optimizing treatment.

Purpose of the Study:

• To determine the incidence of clinically diagnosed abacavir hypersensitivity reaction (HSR) in children receiving abacavir-based therapy within a national program.
• To investigate the association between HLA-B*5701 allele status and the occurrence of abacavir HSR in pediatric patients.
• To identify clinical features differentiating HSR from other conditions in children.

Main Methods:

• An observational study was conducted including all children initiated on abacavir.
• Clinical diagnosis of abacavir HSR was made according to national guidelines.
• HLA-B*5701 testing was performed on children diagnosed with clinical abacavir HSR.

Main Results:

• Out of 101 children who started abacavir, 8 (7.9%) developed clinically diagnosed abacavir HSR.
• Four of the 8 children with HSR had concomitant illnesses and were HLA-B*5701 negative.
• Only 2 (25%) of the children with HSR carried the HLA-B*5701 allele. Fever and abdominal symptoms were more frequent in HLA-B*5701 positive cases.

Conclusions:

• Clinically diagnosed abacavir HSR appears to be overdiagnosed in the pediatric population.
• The presence of concomitant illness may complicate the clinical diagnosis of abacavir HSR.
• Pre-treatment management of concurrent illnesses before initiating abacavir may help reduce the incidence of overdiagnosed HSR.