Abacavir hypersensitivity syndrome

The most important adverse effect of abacavir is a unique and potentially fatal hypersensitivity syndrome. This syndrome is characterized by fever, abdominal pain, and other gastrointestinal complaints a mild maculopapular rash and malaise or fatigue. Respiratory complaints (cough, pharyngitis, dyspnea), musculoskeletal complaints, headache, and paresthesias are reported less commonly. Abacavir is rapidly absorbed and is metabolized to inactivate metabolites by alcohol dehydrogenase and glucuronyl transferase. Alcohol decreases the elimination of abacavir and prolongs its half-life. 

Mank-Seymour AR, Richmond JL, Wood LS, Reynolds JM, Fan YT, Wames GR, Milos PM, Thompson JF (2006) Association of torsades de pointes with novel and known single nucleotide polymorphisms in long QT syndrome genes. Am Heart J 152 1116-1122 Martin AM, Nolan D, Gaudieri S, Almeida CA, Nolan R, James I, Carvalho F, Phillips E, Christiansen FT, Purcell AW, McCluskey J, Mallal S (2004) Predisposition to abacavir hypersensitivity conferred by HLA-B 5701 and a haplotypic Hsp70-Hom variant. Proc Natl Acad Sci U S A 101 4180-4185... 

Zucman D, Truchis P, Majerholc C, Stegman S, Caillat-Zucman S. Prospective screening for human leukocyte antigen-B 5701 avoids abacavir hypersensitivity reaction in the ethnically mixed French HIV population. Journal of Acquired Immune Deficiency Syndromes, 45 1-3, 2007. 

The application of genomics promises to better explain and ultimately reduce some ADRs. Results so far have demonstrated the association in Han Chinese of carbamazepine-indnced Stevens-Johnson syndrome with the HLA-B 15 02 allele and the association of abacavir hypersensitivity in AHS with HLA-B 57 01. 

Narciso P. Parsonage-Turner syndrome a rare case of abacavir hypersensitivity reaction in HIV-infected patients. J Infect 2008 57(1) 88-90. 

Llano A, Brander C. Mechanisms involved in the Abacavir-mediated hypersensitivity syndrome. Cell Res December 2012 22(12) 1637-9. 

Hypersensitivity reactions Serious and sometimes fatal hypersensitivity reactions have been associated with abacavir therapy. Hypersensitivity to abacavir is a multi-organ clinical syndrome usually characterized by a sign or symptom in 2 or more of the following groups ... 

Hypersensitivity reactions, occasionally fatal, have been reported in 2-5% of patients receiving abacavir. Symptoms, which generally occur within the first 6 weeks of therapy, involve multiple organ systems and include fever, malaise, and gastrointestinal complaints. Skin rash may or may not be present. Laboratory abnormalities such as mildly elevated serum aminotransferase or creatine kinase levels are not specific for this reaction. Although the syndrome tends to resolve quickly with discontinuation of medication, rechallenge with abacavir following discontinuation results in return... 

A syndrome of drug hypersensitivity has been described in patients receiving NNRTIs as well as in those receiving amprenavir or abacavir. Serious rashes, including Stevens-Johnson syndrome, have occurred. 

Nervous system The Parsonage-Tumer syndrome, an idiopathic brachial plexus neuritis, has been reported during a hypersensitivity reaction to abacavir in a 35-year-... 

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