Hypersensitivity reactions to HIV therapy

HLA-B*57:01 typing in a Malaysian cohort: implications of abacavir hypersensitivity in people living with HIV

Background: Abacavir (ABC) in combination with other antiretroviral drugs, is used to treat people living with HIV (PLWH). However, it is linked to a fatal hypersensitivity reaction in susceptible individuals, and is strongly associated with the HLA-B*57:01 allele. Materials & methods: A total of 152 patients, 50 PLWH and 102 HIV-1 negative patients, were assessed for the HLA-B*57:01 allele through a sequence-specific primer PCR. Results: All PLWH tested negative for the HLA-B*57:01 allele, but two HIV-negative patients were found to have HLA-B*57, with one of them expressing the HLA-B*57:01 allele. Conclusion: Given the low prevalence of this risk allele in the population, testing for the presence of HLA-B*57:01 in PLWH may not provide significant benefit for the reported population.

Application of KU812 cells for assessing complement activation related effects by nano(bio)materials

Immunocompatibility issues related to nano(bio)materials, particularly liposomal formulations, involving activation of the complement system have been relatively well described however, they highlight the importance of preclinical evaluation of such interactions. These complement-mediated hypersensitivity reactions, in which basophils are implicated, are associated with complement activation-related pseudoallergy (CARPA). Ex vivo investigation of such events using primary basophils is technically challenging due to the relatively limited number of circulating basophils in peripheral blood. In the current work, the KU812 cell line has been applied as an in vitro model for basophil activation to investigate CARPA-related responses following exposure to test materials obtained from the REFINE consortium. To that end, we developed a standard operating procedure measuring a panel of cell-surface markers indicative of basophilic activation. Two laboratories performed the assays, demonstrating a clear difference in responses between liposomal and polymeric nano(bio)materials, while interlaboratory comparison of the standard operating procedure demonstrated reproducibility in results, between the two facilities. These results suggest the potential to use this protocol as a screening method for such responses however, validation using primary basophils is now warranted.

Burgeoning therapeutic strategies to curb the contemporary surging viral infections

Significant efforts and initiatives were already made in the health care systems, however in the last few years; our world is facing emergences of viral infections which potentially leading to considerable challenges in terms of higher morbidity, mortality, increased and considerable financial loads on the affected populations. Over ten major epidemics or pandemics have been recorded in the twenty-first century, the ongoing coronavirus pandemic being one of them. Viruses being distinct obligate pathogens largely dependent on living beings are considered as one of the prominent causes of death globally. Although effective vaccines and antivirals have led to the eradication of imperative viral pathogens, the emergences of new viral infections as well as novel drug-resistant strains have necessitated the implementation of ingenious and efficient therapeutic approaches to treat viral outbreaks in the future. Nature being a constant source of tremendous therapeutical resources has inspired us to develop multi-target antiviral drugs, overcoming the challenges and limitations faced by pharmaceutical industry. Recent breakthroughs in the understanding of the cellular and molecular mechanisms of viral reproduction have laid the groundwork for potential treatment approaches including antiviral gene therapy relying on the application of precisely engineered nucleic acids for disabling pathogen replication. The development of RNA interference and advancements in genome manipulating tools have proven to be especially significant in this regard. In this review, we discussed mode of actions and pathophysiological events associated with the viral infections; followed by distributions, and advancement made towards the detection strategies for timely diagnosis. In the later section, current approaches to cope up the viral pathogens and their key limitations have also been elaborated. Lastly, we also explored some novel and potential targets to treat such infections, where attentions were made on next generation gene editing technologies.

Severe abacavir hypersensitivity reaction in a patient with human immunodeficiency virus infection: a case report

Background

Abacavir is a nucleoside reverse transcriptase inhibitor that is used as a component of the antiretroviral treatment regimen in the management of the human immunodeficiency virus for both adults and children. It is efficacious, but its use may be limited by a hypersensitivity reaction linked with the HLA-B*57:01 genotype. HLA-B*57:01 has been reported to be rare in African populations. Because of the nature of its presentation, abacavir hypersensitivity is prone to late diagnosis and treatment, especially in settings where HLA-B*57:01 genotyping is not routinely done.

Case report

We report a case of a severe hypersensitivity reaction in a 44-year-old Kenyan female living with the human immunodeficiency virus and on abacavir-containing antiretroviral therapy. The patient presented to the hospital after recurrent treatment for a throat infection with complaints of fever, headache, throat ache, vomiting, and a generalized rash. Laboratory results evidenced raised aminotransferases, for which she was advised to stop the antiretrovirals that she had recently been started on. The regimen consisted of abacavir, lamivudine, and dolutegravir. She responded well to treatment but was readmitted a day after discharge with vomiting, severe abdominal pains, diarrhea, and hypotension. Her symptoms disappeared upon admission, but she was readmitted again a few hours after discharge in a hysterical state with burning chest pain and chills. Suspecting abacavir hypersensitivity, upon interrogation she reported that she had taken the abacavir-containing antiretrovirals shortly before she was taken ill. A sample for HLA-B*57:01 was taken and tested positive. Her antiretroviral regimen was substituted to tenofovir, lamivudine, and dolutegravir, and on subsequent follow-up she has been well.

Conclusions

Clinicians should always be cognizant of this adverse reaction whenever they initiate an abacavir-containing therapy. We would recommend that studies be done in our setting to verify the prevalence of HLA-B*57:01.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13256-022-03647-6.

The association of CD4 lymphocyte count with drug hypersensitivity reaction to highly active antiretroviral therapy, trimethoprim sulfamethoxazole, and antitubercular agents in human immunodeficiency virus patients

Background

The introduction of highly active antiretroviral therapy (HAART) and antibiotic regimens for the treatment of human immunodeficiency virus (HIV) and its concomitant opportunistic infections, respectively, significantly improve the morbidity and mortality of the infected patients. However, these drugs commonly cause drug hypersensitivity reactions (DHRs) in patients with acquired immunodeficiency syndrome. The reason proposed are multifactorial, which includes immune hyperactivation, changes in drug metabolism, patient cytokine profiles, oxidative stress, genetic predisposition, and the principal target in HIV patients, the CD4+ lymphocytes.

Objective

This study determined the association of CD4 count and DHRs to first-line HAART, trimethoprim sulfamethoxazole, and antitubercular agents among HIV patients.

Methods

This is a retrospective analytical study. Review of charts were done. The demographic and clinical profile used a descriptive statistics such as mean and standard deviation for quantitative data and frequency and percent for categorical data. Chi-square and Fisher exact tests were used to measure the degree of the relationship of CD4 count and DHRs.

Results

A total of 337 eligible patients were included. There was a 25% incidence of hypersensitivity reactions. However, the prevalence of DHRs across the different CD4 groups was not statistically significant (p = 0.167). Likewise, the study found no significant association between the CD4 count and DHRs to first-line HAART, trimethoprim sulfamethoxazole, and antitubercular agents (p = 0.311). The most common DHR was morbilliform rash, and nevirapine was the most reported antiretroviral drug causing DHR.

Conclusion

There was no association in the CD4 count and DHRs to first-line HAART, trimethoprim sulfamethoxazole, and antitubercular agents. Hence, regardless of the baseline CD4 lymphocyte count, the physician should be vigilant in monitoring hypersensitivity reactions. Patient education on common DHRs is very important upon diagnosis of HIV and/or initiation of treatment.

Pharmacogenetics of HIV therapy: State of the art in Latin American countries

The use of combined antiretroviral therapy (cART) has resulted in a remarkable reduction in morbidity and mortality of people living with HIV worldwide. Nevertheless, interindividual variations in drug response often impose a challenge to cART effectiveness. Although personalized therapeutic regimens may help overcome incidence of adverse reactions and therapeutic failure attributed to host factors, pharmacogenetic studies are often restricted to a few populations. Latin American countries accounted for 2.1 million people living with HIV and 1.4 million undergoing cART in 2020-21. The present review describes the state of art of HIV pharmacogenetics in this region and highlights that such analyses remain to be given the required relevance. A broad analysis of pharmacogenetic markers in Latin America could not only provide a better understanding of genetic structure of these populations, but might also be crucial to develop more informative dosing algorithms, applicable to non-European populations.

Predictors of Subcutaneous Injection Site Reactions to Sustained-Release Buprenorphine in Rhesus Macaques (Macaca mulatta)

Subcutaneous injection site reactions to sustained-release buprenorphine hydrochloride (Buprenorphine SR) in macaques have been reported in only a single case report. In the current study, we evaluated the incidence rate and predictors of buprenorphine SR reactions in the subcutaneous tissue of rhesus macaques (Macaca mulatta) based on retrospective review of macaque buprenorphine SR injection records. Potentially predictive variables were identified with logistic regression modeling and were evaluated using model selection based on Akaike information criterion. Record review revealed sub- cutaneous tissue reactions occurred in 52 (3%) of 1559 injections and were noted between 4 and 311 d after injection. Model selection showed that body weight and MHC allele Mamu-B*29 were the best predictors of subcutaneous reactions. Based on these results, we recommend consideration of potential risk factors prior to the administration of buprenorphine SR to a rhesus macaque. In addition, the authors advise that using the highest concentration of buprenorphine SR available may reduce injection site reaction rates due to the injection of less copolymer.

Mechanistic insights into antiretroviral drug-induced liver injury

All classes of antiretroviral therapy (ART) have been implicated to induce adverse drug reactions such drug-induced liver injury (DILI) and immune-mediated adverse reactions in Human Immunodeficiency Virus (HIV) infected individuals. Patients that develop adverse drug reactions tend to have prolonged stays in hospital and may require to change to alternative regimens if reactions persist upon rechallenge or if rechallenge is contraindicated due to severity of the adverse reaction. Diagnosis of DILI remains a huge obstacle that delays timely interventions, since it is still based largely on exclusion of other causes. There is an urgent need to develop robust diagnostic and predictive biomarkers that could be used alongside the available tools (biopsy, imaging, and serological tests for liver enzymes) to give a specific diagnosis of DILI. Crucial to this is also achieving consensus in the definition of DILI so that robust studies can be undertaken. Importantly, it is crucial that we gain deeper insights into the mechanism of DILI so that patients can receive appropriate management. In general, it has been demonstrated that the mechanism of ART-induced liver injury is driven by four main mechanisms: mitochondrial toxicity, metabolic host-mediated injury, immune reconstitution, and hypersensitivity reactions. The focus of this review is to discuss the type and phenotypes of DILI that are caused by the first line ART regimens. Furthermore, we will summarize recent studies that have elucidated the cellular and molecular mechanisms of DILI both in vivo and in vitro.

Global Frequencies of Clinically Important HLA Alleles and Their Implications For the Cost-Effectiveness of Preemptive Pharmacogenetic Testing

Immune-mediated drug hypersensitivity reactions are an important source of iatrogenic morbidity and mortality. Human leukocyte antigen (HLA)-B*57:01, HLA-B*15:02, HLA-A*31:01, and HLA-B*58:01 constitute established risk factors and preemptive genotyping of these HLA alleles in patients prior to the initiation of abacavir, carbamazepine, and allopurinol-based therapies can prevent toxicity and improve patient outcomes. However, the cost-effectiveness of preemptive HLA testing has only been evaluated in the United States and few countries in Europe and Asia. In this study, we consolidated HLA genotypes from 3.5-6.4 million individuals across up to 74 countries and modeled the country-specific cost-effectiveness of genetic testing. We find major ethnogeographic differences in risk allele prevalence, which translated into pronounced differences in the number of patients needed to test to prevent one case of severe hypersensitivity reactions between countries and populations. At incremental cost-effectiveness ratio thresholds of $40,000, testing of HLA-B*57:01 in patients initiating abacavir was cost-effective in the majority of countries with potential exceptions of East Asia, Saudi Arabia, Ghana, and Zimbabwe. For carbamazepine, preemptive genotyping of HLA-B*15:02 is only cost-effective across most of East and South Asia, whereas HLA-A*31:01 testing is likely to be cost-effective globally. Testing of HLA-B*58:01 is more likely to be cost-effective throughout Africa and Asia compared with Europe and the Americas. We anticipate that this data set can serve as an important resource for clinicians and health economists to guide clinical decision making and inform public healthcare strategies.

The diagnosis of hypersensitivity to antibiotics is rarely confirmed by allergy work-up in cystic fibrosis patients

Cystic fibrosis (CF) patients receive many antibiotic treatments for recurrent respiratory infections and frequently report antibiotic hypersensitivity reactions (HSRs). In this retrospective study, medical records of CF patients were reviewed to clarify the clinical features, the culprit antibiotics, and the prevalence of antibiotic HSRs in the CF population. From 601 CF patients, 95 suspected antibiotic HSRs occurred in 60 patients (prevalence of 10.0%). β-Lactams were the most common inducers, but cotrimoxazole was also frequently involved. Seventy-six of 95 suspected HSRs were assessed by allergy workup including skin tests (43/76 reactions) and/or drug reintroduction as a full course of the culprit antibiotic (73 of 76 reactions). From the 43 suspected HSRs that were skin-tested, only three had positive skin tests and were not subjected to drug readministration. All the other 73 suspected HSRs received a full course of the culprit antibiotic: HSR symptoms recurred in 10 of 73 cases and therefore were considered as confirmed antibiotic HSRs; for the remaining 63 suspected HSRs that did not relapse after drug readministration, the diagnosis of antibiotic HSRs was excluded. In summary, 13 of 76 suspected HSRs were confirmed as antibiotic HSRs. The prevalence of suspected and confirmed antibiotic HSRs in CF patients appears similar to that reported in the general population. Of note, most of the antibiotic suspected HSRs are not confirmed after allergology workup. A complete allergy workup appears therefore crucial to make a correct diagnosis and to avoid unnecessary contraindication of major antibiotics.

Nefritis tubulointersticial aguda. Revisión bibliográfica

La nefritis tubulointersticial aguda hace referencia a un tipo de daño renal que afecta principalmente el intersticio y ocasiona la lesión renal aguda, potencialmente reversible. Su curso puede ser subclínico, con deterioro progresivo hasta evolucionar hacia la insuficiencia renal crónica. La nefritis tubulointersticial aguda tiene múltiples etiologías, las más frecuentes son los medicamentos, productos herbales, las infecciones y las enfermedades autoinmunes. Las principales manifestaciones clínicas son la poliuria, polaquiuria, nocturia, dolor lumbar, microhematuria y leucocituria, aunque puede ser totalmente asintomática. El tratamiento depende de la causa de base y los esteroides juegan un papel importante cuando la condición es de origen medicamentoso o autoinmune. El pronóstico generalmente es bueno, si el problema se identifica de forma oportuna y se trata adecuadamente.

N-acetyltransferase 2 enzyme genotype-phenotype discordances in both HIV-negative and HIV-positive Nigerians

BACKGROUND

The N-acetyltransferase 2 (NAT2) enzyme has been understudied in Nigerians including genotype-phenotype association studies.

OBJECTIVE

The aim of this study was NAT2 haplotype identification and genotype-phenotype investigations in HIV-positive and HIV-negative Nigerians.

PATIENTS AND METHODS

Phenotypes included self-reported sulphonamide hypersensitivity survey, experimental and computational NAT2 phenotyping. The NAT2 gene was amplified by PCR. Gene sequencing used ABI 3730 and Haploview 4.2 for haplotype reconstruction. Genotype-phenotype analyses used the χ P-value and odds ratio with a 95% confidence interval.

RESULTS

Self-reported sulphonamide hypersensitivity showed a prevalence of 3.1 and 12.4% in HIV-positive and HIV-negative Nigerians, respectively. NAT2 genetic variants 191G>A, 282C>T, 341T>C, 481C>T, 590G>A, 803A>G and 857G>A were not significantly different between both groups (odds ratio=0.87; 95% confidence interval: 0.54-1.38, P=0.55). Nine haplotypes: NAT2*4, NAT2*12A, NAT2*13A, NAT2*5B, NAT2*6A, NAT2*7B, NAT2*5C, NAT2*14B and NAT2*14A had frequencies more than 1%, whereas NAT2*12B had 1.1% in the HIV-positive and 0.4% in the HIV-negative group. Overall, slow acetylator haplotypes made up 68%. The NAT2*12 signature single-nucleotide polymorphism was in high linkage disequilibrium with signature single-nucleotide polymorphism for NAT2*13 (D'=0.97, r=0.61) and NAT2*5 (D'=0.98, r=0.64). Genotype-phenotype association analysis showed haplotypes NAT2*13A, NAT2*5C, NAT2*7B and NAT2*14A to be associated strongly with the slow metabolic phenotype (P=0.002, 0.029, 0.032 and 0.050, respectively). Computational phenotypes were similar, with 30.9, 66 and 3.1% for slow, intermediate and rapid acetylators, respectively, among HIV-positive Nigerians and 31.2, 66.3 and 2.5% among the HIV-negative group. Overall, slow phenotypes made up 31%.

CONCLUSION

NAT2 haplotype frequencies are similar in Nigerians, irrespective of HIV status, but genotype-phenotype discordances exist.

Genetic Diversity of HLA Class I and Class II Alleles in Thai Populations: Contribution to Genotype-Guided Therapeutics

Human leukocyte antigen (HLA) class I and II are known to have association with severe cutaneous adverse reactions (SCARs) when exposing to certain drug treatment. Due to genetic differences at population level, drug hypersensitivity reactions are varied, and thus common pharmacogenetics markers for one country might be different from another country, for instance, HLA-A*31:01 is associated with carbamazepine (CBZ)-induced SCARs in European and Japanese while HLA-B*15:02 is associated with CBZ-induced Stevens–Johnson syndrome/toxic epidermal necrolysis (SJS/TEN) among Taiwanese and Southeast Asian. Such differences pose a major challenge to prevent drug hypersensitivity when pharmacogenetics cannot be ubiquitously and efficiently translated into clinic. Therefore, a population-wide study of the distribution of HLA-pharmacogenetics markers is needed. This work presents a study of Thai HLA alleles on both HLA class I and II genes from 470 unrelated Thai individuals by means of polymerase chain reaction sequence-specific oligonucleotide (PCR-SSO) in which oligonucleotide probes along the stretches of HLA-A, -B, -C, -DRB1, -DQA1, and -DQB1 genes were genotyped. These 470 individuals were selected according to their regional locations, which were from North, Northeast, South, Central, and a capital city, Bangkok. Top ranked HLA alleles in Thai population include HLA-A*11:01 (26.06%), -B*46:01 (14.04%), -C* 01:02 (17.13%), -DRB1*12:02 (15.32%), -DQA1*01:01 (24.89%), and -DQB1*05:02 (21.28%). The results revealed that the distribution of HLA-pharmacogenetics alleles from the South had more HLA-B75 family that a typical HLA-B*15:02 pharmacogenetics test for SJS/TEN screening would not cover. Besides the view across the nation, when compared HLA alleles from Thai population with HLA alleles from both European and Asian countries, the distribution landscape of HLA-associated drug hypersensitivity across many countries could be observed. Consequently, this pharmacogenetics database offers a comprehensive view of pharmacogenetics marker distribution in Thailand that could be used as a reference for other Southeast Asian countries to validate the feasibility of their future pharmacogenetics deployment.

Safety implications of combined antiretroviral and anti-tuberculosis drugs

Introduction: Antiretroviral and anti-tuberculosis (TB) drugs are often co-administered in people living with HIV (PLWH). Early initiation of antiretroviral therapy (ART) during TB treatment improves survival in patients with advanced HIV disease. However, safety concerns related to clinically significant changes in drug exposure resulting from drug-drug interactions, development of overlapping toxicities and specific challenges related to co-administration during pregnancy represent barriers to successful combined treatment for HIV and TB.Areas covered: Pharmacokinetic interactions of different classes of ART when combined with anti-TB drugs used for sensitive-, drug-resistant (DR) and latent TB are discussed. Overlapping drug toxicities, implications of immune reconstitution inflammatory syndrome (IRIS), safety in pregnancy and research gaps are also explored.Expert opinion: New antiretroviral and anti-tuberculosis drugs have been recently introduced and international guidelines updated. A number of effective molecules and clinical data are now available to build treatment regimens for PLWH with latent or active TB. Adopting a systematic approach that also takes into account the need for individualized variations based on the available evidence is the key to successfully integrate ART and TB treatment and improve treatment outcomes.

The Signaling Pathways, and Therapeutic Targets of Antiviral Agents: Focusing on the Antiviral Approaches and Clinical Perspectives of Anthocyanins in the Management of Viral Diseases

As the leading cause of death worldwide, viruses significantly affect global health. Despite the rapid progress in human healthcare, there are few viricidal and antiviral therapies that are efficient enough. The rapid emergence of resistance, and high costs, as well as the related side effects of synthetic antiviral drugs, raise the need to identify novel, effective, and safe alternatives against viral diseases. Nature has been of the most exceptional help and source of inspiration for developing novel multi-target antiviral compounds, affecting several steps of the viral life cycle and host proteins. For that matter and due to safety and efficacy limitations, as well as high resistance rate of conventional therapies, hundreds of natural molecules are preferred over the synthetic drugs. Besides, natural antiviral agents have shown acceptable antiviral value in both preclinical and clinical trials.This is the first review regarding molecular and cellular pathways of the virus life cycle, treatment strategies, and therapeutic targets of several viral diseases with a particular focus on anthocyanins as promising natural compounds for significant antiviral enhancements. Clinical applications and the need to develop nano-formulation of anthocyanins in drug delivery systems are also considered.

Drug hypersensitivity in HIV infection

PURPOSE OF REVIEW

Immune-mediated adverse drug reactions (IM-ADRs) are many times more common in HIV-infected patients. Usual offending drugs include antiretroviral and antiinfectives, but the burden of specific drug IM-ADRs is population-specific; changing as new and fixed dose combinations enter the market, and drug-resistance patterns demand. This review considers recent literature on epidemiology, mechanisms, clinical management and prevention of IM-ADRs amongst persons living with HIV/AIDS.

RECENT FINDINGS

Epidemiological studies continue to describe high rates of delayed hypersensitivity to known offenders, as well as similar reactions in preexposure prophylaxis. IM-ADRs to oral and injectable integrase strand transfer inhibitors are reported with expanding use. The clinical spectrum and management of IM-ADRs occurring in HIV-infected populations is similar to uninfected; with exceptions such as a recently described severe delayed efavirenz DILI with high mortality. Furthermore, the context can be unique, such as the lower than expected mortality in a Stevens-Johnson syndrome and toxic epidermal necrolysis (SJS/TEN) cohort from a HIV/TB high burden setting. Programmatic data showing the near complete elimination of Abacavir drug hypersensitivity syndrome following implementation of HLA-B57:01 screening is a stellar example of how prevention is possible with mechanistic insight.

SUMMARY

IM-ADRs remain a challenge in persons living with HIV. The complexities posed by polypharmacy, overlapping drug toxicities, drug interactions, overlap of IM-ADRs with other diseases, limited alternative drugs, and vulnerable patients with advanced immunosuppression with high mortality, necessitate increased use of drug provocation testing, treat-through and desensitization strategies. There is an urgent need for improved diagnostics and predictive biomarkers for prevention, or to guide treat-through, rechallenge and desensitization approaches.

HIV/AIDS: An Update for Home Healthcare Clinicians

Human immunodeficiency virus (HIV) infection, once fatal, has become a chronic disease that can be treated and well-managed. Antiretroviral treatment (ART) can result in undetectable levels of HIV in the bloodstream. The risk factors, transmission, diagnosis, treatment, acute HIV infection, potential opportunistic infections, and malignancies should be understood by all those caring for persons living with HIV. Preventive treatment is possible with preexposure and postexposure prophylaxis regimens. Home healthcare providers can assist individuals to adhere to medication regimens, monitor efficacy of treatment, recognize complications of HIV and side effects of ART. Most importantly, they can support, educate, and counsel persons living with HIV and their families.

Drug-Induced Skin Adverse Reactions: The Role of Pharmacogenomics in Their Prevention

Adverse drug reactions (ADRs) affect many patients and remain a major public health problem, as they are a common cause of morbidity and mortality. It is estimated that ADRs are responsible for about 6% of hospital admissions and about 9% of hospitalization costs. Skin is the organ that is most frequently involved in ADRs. Drug-induced skin injuries vary from mild maculopapular eruptions (MPE) to severe cutaneous adverse reactions (SCARs) that are potentially life threatening. Genetic factors have been suggested to contribute to these SCARs, and most significant genetic associations have been identified in the major histocompatibility complex (MHC) genes. Common drugs associated with SCARs connected with strong genetic risk factors include antiepileptic drugs (AEDs), allopurinol, abacavir, nevirapine, sulfonamides, dapsone, non-steroidal anti-inflammatory drugs (NSAIDs), and analgesic drugs. However, genetic associations vary between different ethnic populations. Differences may in part be explained by the different prevalence of HLA (human leukocyte antigen) alleles among ethnic groups. In this review, we present and discuss the recent advances in genetic associations with ADRs in the skin. Many of these ADRs are now preventable with pharmacogenetic screening.

The impact of a therapeutic exercise intervention on depression and body self-image in HIV-positive women in sub-Saharan Africa

INTRODUCTION

Attitudes, responses, and reactions of HIV-positive women in three sub-Saharan African regions toward a therapeutic exercise intervention, aimed to determine the presence of depression and low body self-image, were captured. This provided insight into body satisfaction and desire to exercise (Stage 1, n=60), body self-image and depression (Stage 2, n=60), and overall concerns around the often adverse side effects of antiretroviral treatment (ART). A program of therapeutic (specialty) exercise was developed for the experimental design (Stage 2), to quantify the psychological side effects of these variables.

METHODOLOGY

Stage 1 constituted a qualitative exploration into attitudes and perceptions around ART, toxicity, health concerns, metabolic irregularities (lipodystrophy), body shape and size dissatisfaction, and cultural attitudes toward exercise. This stage deployed brief informal face-to-face interviews, based on the World Health Organization (WHO)/United Nations Fund for Population Activities (UNFPA) AIDS Inventory, in three sub-Saharan African regions (including provincial and district hospitals, nongovernmental organizations, voluntary counseling and testing/HIV and testing centers, and primary care outpatient clinics). Stage 2 of the study comprised a quantitative experimental design, conducted on a sample of HIV-positive women (mean age=39.0 years; mean years on ART=5.5; 86% black) in three selected HIV outpatient clinics in Johannesburg, South Africa.

DATA ANALYSIS

The collated data sets from both stages of the research were presented, analyzed, and interpreted (thematic analyses [Stage 1] and statistical analyses [Stage 2]) using the body self-image questionnaire and Beck's depression inventory.

RESULTS

Stage 1 outlined participants' concerns and reports around 1) body shape and size, including long-term effects of ART and 2) attitudes toward exercise, as a function of HIV status. Stage 2 represented pre- and posttest statistics, showing low statistical means for both the experiment and the control groups, with statistical significance for four out of nine items of subscales of body self-image questionnaire.

Mortality from adverse drug reaction-related hospitalizations in south-west Ethiopia: A cross-sectional study

WHAT IS KNOWN AND OBJECTIVE

Adverse drug reactions (ADRs) are an important cause of mortality during medical care. To our knowledge, no Ethiopian studies have reported on mortality due to ADRs in patients presenting to hospital from the community setting. The aim of this study was to determine the mortality rate attributable to ADRs in patients presenting to hospital, identify drugs implicated in the ADR-related deaths and identify factors contributing to ADR-related mortality at Jimma University Specialised Hospital (JUSH), south-west Ethiopia METHODS: This cross-sectional study included 1001 patients aged ≥18 years consecutively admitted to medical wards from May 2015 to August 2016. ADR-related mortality was determined through detailed review of medical records, laboratory tests and patient interviews followed by causality assessment by the Naranjo algorithm and expert consensus.

RESULTS

Of 1001 patients, 15, 1.5% (95% confidence interval [CI]: 0.80%-2.30%) died with an ADR. The primary suspected causes of death were drug-induced hepatotoxicity (7, 43.8%) followed by acute kidney injury (4, 25.0%). Isoniazid (6, 33.3%), pyrazinamide (3, 16.7%), efavirenz (2, 11.1%) and tenofovir (2, 11.1%) were commonly implicated drugs. The majority of ADRs (14, 93.8%) were preventable. Unadjusted bivariate comparisons suggested patients who died with ADRs were more likely to have pre-existing liver disease (40.0% vs 7.0%; 95% confidence interval [CI]: 8.1%-57.8%), a history of ADRs (40% vs 1.4%; 95% CI: 13.8%-63.4%), a lower mean (±SD) body mass index (BMI, 17.6 ± 2.1 vs 20.0 ± 2.9 kg/m² ; 95% CI = 0.9-3.9), exposure to antitubercular (46.7% vs 18.9%; 95% CI: 2.3%-53.1%) and antiretroviral (40.0% vs 7.7%; 95% CI: 7.5%-57.2%) therapies, and a higher mean number of medications (7.1 ± 3.3 vs 3.8 ± 2.1; 95% CI: 2.2-4.4) and Charlson Comorbidity Index (3.9 ± 2.9 vs 1.6 ± 1.8; 95% CI: 1.4-3.2) than surviving patients without ADRs.

WHAT IS NEW AND CONCLUSION

Fatal ADRs were common in patients presenting to hospital. The drugs implicated were mostly antitubercular and antiretroviral therapies, reflecting the high burden of HIV and tuberculosis in the study population. ADR-related deaths were significantly associated with poor nutritional status. The majority of ADR-related deaths were preventable, highlighting the need to develop a multidisciplinary approach to closely monitor patients who are prescribed antitubercular and antiretroviral therapies, particularly in patients with hepatic disease, a history of ADRs, who are malnourished and who are exposed to multiple medications.

Oral Provocation Testing in Cutaneous Adverse Drug Reactions to Antiretroviral and Antitubercular Therapy: A Study at a Tertiary Care Hospital in South India

AIM

To collect data pertaining to oral drug provocation testing (DPT) in hospitalized patients with antiretroviral (ARV)/antitubercular agent-induced rashes.

METHODS

Patients with cutaneous adverse drug reactions (ADRs) to ARV/antitubercular drugs and who underwent oral DPT during a 5-year period were included in this study.

RESULTS

Data were collected from the records of 21 patients. Of the 21, 19 had HIV infection. The most commonly implicated drug was nevirapine (NVP), followed by cotrimoxazole and antitubercular agents. Of the 11 ADRs that occurred on rechallenge, the ADR on rechallenge was similar in clinical presentation to the initial ADR in 6 patients, while a different rash was elicited in 5 patients.

CONCLUSION

Oral DPT is a safe and effective tool to accurately diagnose ADRs, especially in patients on multiple drugs and in situations such as HIV infection and tuberculosis where second-line agents are expensive and/or not easily available through the national AIDS control/tuberculosis programs.

Abacavir usage patterns and hypersensitivity reactions in the EuroSIDA cohort

OBJECTIVES

Five to eight per cent of HIV-positive individuals initiating abacavir (ABC) experience potentially fatal hypersensitivity reactions (HSRs). We sought to describe the proportion of individuals initiating ABC and to describe the incidence and factors associated with HSR among those prescribed ABC.

METHODS

We calculated the proportion of EuroSIDA individuals receiving ABC-based combination antiretroviral therapy (cART) among those receiving cART after 1 January 2009. Poisson regression was used to identify demographic, and current clinical and laboratory factors associated with ABC utilization and discontinuation.

RESULTS

Between 2009 and 2016, of 10 076 individuals receiving cART, 3472 (34%) had ever received ABC-based cART. Temporal trends of ABC utilization were also heterogeneous, with 28% using ABC in 2009, dropping to 26% in 2010 and increasing to 31% in 2016, and varied across regions and over time. Poisson models showed lower ABC utilization in older individuals, and in those with higher CD4 cell counts, higher cART lines, and prior AIDS. Higher ABC utilization was associated with higher HIV RNA and poor renal function, and was more common in Central-East and Eastern Europe and lowest during 2014. During 779 person-years of follow-up (PYFU) in 2139 individuals starting ABC after 1 January 2009, 113 discontinued ABC within 6 weeks of initiation for any reason [incidence rate (IR) 14.5 (95% confidence interval (CI) 12.1, 17.5) per 100 PYFU], 13 because of reported HSR [IR 0.3 (95% CI 0.1, 1.0) per 100 PYFU] and 35 because of reported HSR/any toxicity [IR 4.5 (95% CI 3.2, 6.3) per 100 PYFU]. There were no factors significantly associated with ABC discontinuation because of reported HSR/any toxicity.

CONCLUSIONS

ABC remains commonly used across Europe and the incidence of discontinuation because of reported HSR was low in our study population.

Severe cutaneous adverse reactions to drugs

During the past decade, major advances have been made in the accurate diagnosis of severe cutaneous adverse reactions (SCARs) to drugs, management of their manifestations, and identification of their pathogenetic mechanisms and at-risk populations. Early recognition and diagnosis of SCARs are key in the identification of culprit drugs. SCARS are potentially life threatening, and associated with various clinical patterns and morbidity during the acute stage of Stevens-Johnson syndrome and toxic epidermal necrolysis, drug reactions with eosinophilia and systemic symptoms, and acute generalised exanthematous pustulosis. Early drug withdrawal is mandatory in all SCARs. Physicians' knowledge is essential to the improvement of diagnosis and management, and in the limitation and prevention of long-term sequelae. This Seminar provides the tools to help physicians in their clinical approach and investigations of SCARs.

HLA-associated drug hypersensitivity and the prediction of adverse drug reactions

Adverse drug reactions are an important cause of morbidity and mortality and constitute the leading reason of drug withdrawal from the market. Besides classical reactions that are related to pharmacologic activity of the drug, some reactions are unpredictable, not dose dependent, and seem to occur in genetically predisposed individuals. The majority of this reaction is immunologically driven and they are referred to as hypersensitivity reactions. A growing number of studies provided evidences that specific HLA alleles increase the risk of developing hypersensitivity drug reactions. In this context, drug hypersensitivities that have more robust pharmacogenetic data include abacavir hypersensitivity syndrome and severe cutaneous adverse reactions induced by allopurinol and carbamazepine.

Prevalence of abacavir-associated hypersensitivity syndrome and HLA-B*5701 allele in a Portuguese HIV-positive population

Background

Human Immunodeficiency Virus (HIV)-positive patients treated with the antiretroviral drug abacavir (ABC) may develop a potentially fatal ABC-associated hypersensitivity syndrome (ABC-HS), typically characterized by fever, malaise, rash, vomiting/diarrhoea and/or dyspnoea/cough. ABC-HS has been strongly associated with HLA-B*57:01 carriage and screening for this allele is recommended.

Objective

To determine the prevalence of HLA-B*57:01 and to characterize suspected ABC-HS in the adult HIV population from our hospital during a 7-year period.

Methods

Clinical data on patients under ABC treatment from January 2006 to December 2012 were analyzed to search for symptoms of ABC-HS. Reactions of suspected ABC-HS were characterized. HLA-B*57:01 and patch tests (1% and 10% ABC in petrolatum) with readings at 48 h were performed in those without previous testing. From January 2008 routine HLA-B*57:01 screening was implemented.

Results

From January 2006 to December 2007, 186 patients began treatment with ABC (data from 163 were available): 7 (4%) patients stopped ABC for suspected ABC-HS (71% males, median age 45 years) and the median time for onset of the reaction after starting ABC was 7 days. Four of the 7 patients had the HLA-B*57:01 allele and 2 of these 4 had positive patch tests. After HLA-B*57:01 screening implementation (January 2008), 573 patients were evaluated and 35 (6.1%) were HLA-B*57:01 positive; no suspected ABC-HS were observed since then.

Conclusion

Four patients with suspected ABC-HS (of 6 screened) were HLA-B*57:01 positive. No ABC-HS occurred since January 2008, after HLA-B*57:01 screening was implemented.

Individualization of antiretroviral therapy--pharmacogenomic aspect

Combination therapy with three drug regimens for human immunodeficiency virus (HIV) infection significantly suppresses the viral replication. However, this therapeutic impact is restricted by adverse drug events and response in terms of short and long term efficacy. There are multiple factors involved in different responses to antiretrovirals (ARVs) such as age, body weight, disease status, diet and heredity. Pharmacogenomics deals with individual genetic make-up and its role in drug efficacy and toxicity. In depth genetic research has provided evidence to predict the risk of developing certain toxicities for which personalized screening and surveillance protocols may be developed to prevent side effects. Here we describe the use of pharmacogenomics for optimal use of HAART (highly active antiretroviral therapy).

Key toxicity issues with the WHO-recommended first-line antiretroviral therapy regimen

INTRODUCTION

WHO recommends tenofovir, efavirenz, and lamivudine or emtricitabine for first-line antiretroviral therapy (ART) in adults, which replaced more toxic regimens using stavudine, zidovudine or nevirapine. Areas covered: We searched Pubmed to identify observational studies and randomized controlled trials reporting toxicity of these antiretrovirals published between 2011 and 2016, and hand-searched abstracts presented at major HIV conferences in 2015 and 2016, focusing on data from sub-Saharan Africa. Tenofovir's nephrotoxicity manifests as mild renal tubular dysfunction (common and of uncertain clinical significance), acute kidney injury (rare), and chronic declining glomerular filtration rate (common). African studies, which include high proportions of patients with renal dysfunction from opportunistic diseases, report population improvement in renal function after starting tenofovir-based ART. Tenofovir modestly decreases bone mineral density, and there is emerging data that this increases fracture risk. Efavirenz commonly causes early self-limiting neuropsychiatric toxicity and hypersensitivity rashes. Recent studies have highlighted its long-term neuropsychiatric effects, notably suicidality and neurocognitive impairment, and metabolic toxicities (dyslipidemia, dysglycemia, and lipoatrophy). We point out the challenges clinicians face in the recognition and attribution of adverse drug reactions. Expert commentary: Tenofovir and efavirenz are generally well tolerated, but both are associated with potentially serious toxicities. Pharmacovigilance systems in resource-limited settings with high HIV burden should be strengthened.

Severe antiretroviral-associated skin reactions in South African patients: a case series and case-control analysis

PURPOSE

Severe skin reactions may complicate combination antiretroviral therapy (cART). Nevirapine is known to be associated with severe skin reactions, but there are conflicting data on risk factors in African patients. We reviewed cases of severe skin reactions admitted to a tertiary hospital in Cape Town, South Africa. We identified associations with severe skin reactions in patients on cART.

METHODS

We described severe skin reaction cases in patients taking cART admitted to Groote Schuur Hospital in Cape Town, South Africa, between 2006 and 2012. We included those patients who developed a severe skin reaction within 120 days of cART initiation in a case-control analysis. We identified control patients matched on date of cART initiation and primary care facility by linkage with the Western Cape electronic provincial HIV database. We conducted a conditional (fixed effects) logistic regression modelling.

RESULTS

We identified 169 severe skin reactions in patients on cART. The most common presentations were Stevens Johnson syndrome/toxic epidermal necrolysis (49%) and drug hypersensitivity syndrome (36%). One hundred forty-one patients were female, of which 27 were pregnant. Median duration of hospitalization was 12 days (interquartile range 8 to 19) and six patients died. We included 91 cases and 361 matched controls in the analysis. Severe skin reaction was associated with nevirapine exposure, adjusted odds ratio of 7.6 (95%CI 3.7 to 15.7) and with pregnancy, adjusted odds ratio 3.7 (95%CI 1.3 to 10.8) compared with men.

CONCLUSIONS

Severe skin reactions resulted in prolonged admission to hospital in this setting. We found that nevirapine use and pregnancy are independently associated with severe skin reaction. Copyright © 2016 John Wiley & Sons, Ltd.

Nevirapine: Most Common Cause of Cutaneous Adverse Drug Reactions in an Outpatient Department of a Tertiary Care Hospital

INTRODUCTION

Skin is the most commonly involved organ in adverse drug reactions. Most of the cutaneous adverse drug reactions (CADRs) being of mild to moderate severity are likely to be diagnosed and treated in an outpatient setting. Consequently, knowledge regarding morphological pattern, severity and drugs implicated in causation of these CADRs has important implications for healthcare personnel.

AIM

To determine the current clinical pattern of CADRs and to assess their causality and severity with the help of standard scales.

STUDY DESIGN AND SETTING

A prospective, observational study was conducted in the outpatient department of skin and venereal disease in a tertiary care hospital.

MATERIALS AND METHODS

Patients with suspected CADR after consumption of systemic drug(s) were enrolled in the study. Data regarding demographics, clinical manifestations of CADR, drug history preceding the reaction, concomitant illness, relevant laboratory investigations etc was obtained. This data was then analysed for morphological pattern, causality and severity. CADRs with causality assessment possible and above on the basis of World Health Organization-Uppsala Monitoring Centre causality assessment system were considered for analysis.

STATISTICS

Descriptive statistics were used to express results of pattern, severity and causality of CADRs.

RESULTS

Ninety patients were enrolled in the study. Male to female ratio for CADRs was 1:2.33. Maculopapular rash was most commonly encountered CADR in 76.67% cases followed by urticaria (8.89%), Stevens-Johnson syndrome (4.4%) and fixed dose eruptions (3.33%). Antiretrovirals were implicated in 75.56% (68/90) of CADRs. Nevirapine was suspected in 52 out of 90 (57.77%) cases of CADRs which included 39 cases of maculopapular rash, five cases of urticaria, four cases of Stevens-Johnson syndrome, and two cases each of pustular rash and angioedema respectively. Antimicrobials, antiepileptics and Non-steroidal Anti-inflammatory Drugs (NSAIDs) were other suspected drugs.

CONCLUSION

Antiretrovirals especially nevirapine was implicated in variety of CADRs ranging from maculopapular rash to life-threatening reactions like Stevens-Johnson syndrome in an outpatient setting. Women were twice as susceptible as men for CADRs.

Parsing interindividual drug variability: an emerging role for systems pharmacology

There is notable interindividual heterogeneity in drug response, affecting both drug efficacy and toxicity, resulting in patient harm and the inefficient utilization of limited healthcare resources. Pharmacogenomics is at the forefront of research to understand interindividual drug response variability, but although many genotype-drug response associations have been identified, translation of pharmacogenomic associations into clinical practice has been hampered by inconsistent findings and inadequate predictive values. These limitations are in part due to the complex interplay between drug-specific, human body and environmental factors influencing drug response and therefore pharmacogenomics, whilst intrinsically necessary, is by itself unlikely to adequately parse drug variability. The emergent, interdisciplinary and rapidly developing field of systems pharmacology, which incorporates but goes beyond pharmacogenomics, holds significant potential to further parse interindividual drug variability. Systems pharmacology broadly encompasses two distinct research efforts, pharmacologically-orientated systems biology and pharmacometrics. Pharmacologically-orientated systems biology utilizes high throughput omics technologies, including next-generation sequencing, transcriptomics and proteomics, to identify factors associated with differential drug response within the different levels of biological organization in the hierarchical human body. Increasingly complex pharmacometric models are being developed that quantitatively integrate factors associated with drug response. Although distinct, these research areas complement one another and continual development can be facilitated by iterating between dynamic experimental and computational findings. Ultimately, quantitative data-derived models of sufficient detail will be required to help realize the goal of precision medicine.

Diagnostic accuracy of HLA-B*57:01 screening for the prediction of abacavir hypersensitivity and clinical utility of the test: a meta-analytic review

AIM

To determine diagnostic accuracy of HLA-B*57:01 testing for prediction of abacavir-induced hypersensitivity and to quantify the clinical benefit of pretreatment screening through a meta-analytic review of published studies.

METHODS

A comprehensive search was performed up to June 2013. The methodological quality of relevant studies was assessed by the QUADAS-2 tool. The pooled diagnostic estimates were calculated using a random effect model.

RESULTS

Despite the presence of heterogeneity in sensitivity or specificity estimates, the pooled diagnostic odds ratio to detect abacavir-induced hypersensitivity on the basis of clinical criteria was 33.07 (95% CI: 22.33-48.97, I(2): 13.9%), while diagnostic odds ratio for detection of immunologically confirmed abacavir hypersensitivity was 1141 (95% CI: 409-3181, I(2): 0%). Pooled analysis of risk ratio showed that prospective HLA-B*57:01 testing significantly reduced the incidence of abacavir-induced hypersensitivity.

CONCLUSION

This meta-analysis demonstrates an excellent diagnostic accuracy of HLA-B*57:01 testing to detect immunologically confirmed abacavir hypersensitivity and corroborates existing recommendations.

A Prospective Screening of HLA-B*57.01 Allelic Variant for Preventing the Hypersensivity Reaction to Abacavir: Experience from the Laboratory of Molecular Biology of the Infectious Diseases Division at the University Hospital of Salerno

Abacavir is a nucleoside reverse transcriptase inhibitor largely used as part of the antiretroviral therapy in Human Immunodeficiency Virus (HIV)-infected patients. Some individuals (2-9%) who start an abacavir treatment show an immunologic reaction indicated as hypersensitivity reaction syndrome (HSR) that is often responsible for therapy discontinuation and could represent a life-threatening event. Some studies demonstrated a correlation between this adverse reaction and the class I of the major histocompatibility complex (MHC) allele, HLA-B*57.01, in several populations, including Caucasians. Nowadays, International HIV treatment guidelines recommend the HLA-B*57.01 genotyping before abacavir administration to reduce the incidence of HSR. Both male and female HIV-infected patients were enrolled at the Infectious Diseases Division at the University Hospital of Salerno, and admitted to a prospective HLAB*57.01 screening. Genetic analysis was carried out through two sequential Real-Time PCR reactions in which Sybr-Green was used. Out of 248 patients, 215 were Italians from Southern Italy and 33 were coming from several non-EU members countries. All were genotyped: 6 Italians (2.8%) and 1 of the non-EU group (3%) were identified as HLAB*57.01 carriers. In this paper we present our experience in the field of abacavir pharmacogenetic and confirm the importance of Real Time PCR as a valid and cost-effective HLA-B*57.01 typing methodology.

Hypersensitivity Reaction Associated with Abacavir Therapy in an Indian HIV Patient - A Case Report

The most important and unique adverse effect of abacavir (ABC) is fatal hypersensitivity reaction (HSR). The objective of this report is to describe a case of ABC induced HSR that occurred in an Indian HIV patient during treatment. Although this adverse effect is not uncommon, it is perhaps underreported or has never been reported so far in an Indian case scenario. A 44-year-old known case of HIV-1 was admitted in view of his worsening condition and very low CD4 cell counts 3 cells/μL. He was on anti-retroviral therapy since three years but not regular. On the basis of treatment failure, non-compliance and progressive low CD4 counts, the anti HIV regime was switched over to abacavir 600 mg+ atazanavir/ ritonavir 300mg/100mg Two weeks after ABC therapy he presented with maculopapular rash, headache and signs of hepatic damage (serum AST, ALP and ALT increased to 3-4 fold) suggestive of hypersensitivity reaction. As we know discontinuation of the drug is the ultimate litmus test to confirm diagnosis of drug induced adverse reaction. We did confirm ABC induced HSR by de-challenge wherein, rash disappeared within 2-3 days and LFT came back to normal within 5 days. However, no rechallenge was done. HSR was more in favour of ABC because atazanavir failed to produce any similar reaction after re-challenge.

Detection of HLA-B*57:01 by real-time PCR: implementation into routine clinical practice and additional validation data

Aim:HLA-B*57:01 status needs to be determined before initiating abacavir therapy. We developed a pharmacogenetic real-time (Q)-PCR screening test using two sets of sequence specific primers. This test has been implemented into routine clinical practice. Materials & methods: HIV-infected patients admitted at our University Hospital were thus genotyped using the above mentioned test. A panel of 80 DNA samples with a known genotype were used to characterize Q-PCR conditions using different master mixes. Results: A total of 353 patients were genotyped, detecting 15 (4.25%) HLA-B*57:01 positive carriers. Among the negative patients, 17.2% were treated with abacavir without any hypersensitivity reaction. Using different Q-PCR master mixes, significantly lower cutoff Ct values were found, thus new analytical settings are provided. Conclusion: The pharmacogenetic test developed in our laboratory for the fast screening of HLA-B*57:01 can be successfully implemented into routine clinical practice. All 16 sequences (including an additional six) currently known for the HLA-B*57:01 allele are detected by sequence specific primers used in this test. The Brilliant II SYBR® Green QPCR MM (Stratagene) can safely replace the master mix originally used to develop the test.

Original submitted 2 August 2013; Revision submitted 2 December 2013

Drug hypersensitivity in human immunodeficiency virus-infected patient: challenging diagnosis and management

Human immunodeficiency virus (HIV)-infected patients present complex immunological alterations. Multiple drugs that usually prescribed for prevention or treatment of opportunistic infections and antiretroviral pose these patients a higher risk of developing drug hypersensitivity. All antiretroviral agents and drugs to treat opportunistic infections have been reported to cause drug hypersensitivity reactions. Allergic reactions with antiretroviral are not restricted to older agents, although newer drugs usually more tolerated. Cutaneous adverse drug reactions are the most common manifestation of drug hypersensitivity in HIV, typically manifesting as maculopapular rash with or without systemic symptoms in the presence or absence of internal organ involvement. The onset of an allergic reaction is usually delayed. Severe drug hypersensitity reactions as erythema multiforme, Stevens Johnson syndrome and toxic epidermal necrolysis develop more often in HIV-infected patients compared to other populations. Mild to moderate rash without systemic symptom or organ involvement usually do not need drug discontinuation. Appropriate diagnosis and management of drug hypersensitivity reactions are essential, especially in patients with very low CD4+ T-cell count and multiple opportunistic infections. Clinicians should aware of different half-life of each drug when decided to stop the drug. Knowledge of the metabolism, recognition of the risk factors, and the ability to suggest the probability of particular drug as causative are also important points. A step wise rechallenge test or desensitization with the offending drug might be a preferable action and more commonly used in managing drug hypersensitivity in HIV-infected patients. Desensitization protocols have been successfully done for several antiretroviral and opportunistic infection drugs.

Hypersensitivity and Desensitization to Darunavir in a Case of HIV Infection with Triple-Class Drug Resistance

We report on a case of severe cutaneous reaction to darunavir/r and a successful desensitization protocol. The patient was a 41-year-old female, known to be HIV infected for 18 years and who had received several drug regiments in the past. As a consequence, her virus had triple-class mutations but was susceptible to darunavir/r. Her CD4 was 200 cells/mm3 and HIV viral load 56,000 copies/mL. Eight days after initiation of darunavir/r the patient developed a severe pruritic vesicular extended cutaneous allergic reaction which required cessation of all drugs. Due to the severity of the allergic reaction no rechallenge was done. After the patient's recovery, the virus was found to be susceptible only to maraviroc, raltegravir, and darunavir/r. Since darunavir/r was an essential component in treating this triple-class mutated virus, a desensitization protocol was applied successfully. Six months after desensitization, the patient is asymptomatic, compliant, and her HIV viral load remains at <20 copies/mL.

Current assays for HIV-1 diagnostics and antiretroviral therapy monitoring: challenges and possibilities

In 2011, there were over 34 million people living with HIV infections, placing a heavy burden on public health sectors. HIV infection is a lifelong threat that cannot be prevented by vaccination or cured by antiretroviral drugs. The infected patients rely on daily antiretroviral therapy to suppress HIV viral replication. Hence, it is important to diagnose HIV infections as early as possible and to monitor the efficacy of antiretroviral therapy every 3–6 months. Different immunoassays detecting HIV antigens and antibodies have been modified to offer better sensitivity and more rapid diagnosis. Several clinical and virological parameters, including CD4+ cell counts, viral load and drug resistance mutations, are also used for treatment monitoring. Many molecular assay optimizations are now being utilized to improve patient care. This review will focus on the most updated HIV diagnostic assays, as well as discussing the upcoming possibilities of other advanced technologies.

Underlying genetic structure impacts the association between CYP2B6 polymorphisms and response to efavirenz and nevirapine

OBJECTIVE

CYP2B6 variation predicts pharmacokinetic characteristics of its substrates. Consideration for underlying genetic structure is critical to protect against spurious associations with the highly polymorphic CYP2B6 gene.

DESIGN

The effect of CYP2B6 variation on response to its substrates, nonnucleoside reverse transcriptase inhibitors (NNRTIs), was explored in the Women's Interagency HIV Study.

METHODS

Five putative functional polymorphisms were tested for associations with virologic suppression within 1 year after NNRTI initiation in women naive to antiretroviral agents (n = 91). Principal components were generated to control for population substructure. Logistic regression was used to test the joint effect of rs3745274 and rs28399499, which together indicate slow, intermediate, and extensive metabolizers.

RESULTS

Rs3745274 was significantly associated with virologic suppression [odds ratio = 3.61, 95% confidence interval (CI) 1.16-11.22, P trend = 0.03]; the remaining polymorphisms tested were not significantly associated with response. Women classified as intermediate and slow metabolizers were 2.90 (95% CI 0.79-12.28) and 13.44 (95% CI 1.66 to infinity) times as likely to achieve virologic suppression compared to extensive metabolizers after adjustment for principal components (P trend = 0.005). Failure to control for genetic ancestry resulted in substantial confounding of the relationship between the metabolizer phenotype and treatment response.

CONCLUSION

The CYP2B6 metabolizer phenotype was significantly associated with virologic response to NNRTIs; this relationship would have been masked by simple adjustment for self-reported ethnicity. Given the appreciable genetic heterogeneity that exists within self-reported ethnicity, these results exemplify the importance of characterizing underlying genetic structure in pharmacogenetic studies. Further follow-up of the CYP2B6 metabolizer phenotype is warranted, given the potential clinical importance of this finding.

Interplay between HIV-1 and Host Genetic Variation: A Snapshot into Its Impact on AIDS and Therapy Response

As of February 2012, 50 circulating recombinant forms (CRFs) have been reported for HIV-1 while one CRF for HIV-2. Also according to HIV sequence compendium 2011, the HIV sequence database is replete with 414,398 sequences. The fact that there are CRFs, which are an amalgamation of sequences derived from six or more subtypes (CRF27_cpx (cpx refers to complex) is a mosaic with sequences from 6 different subtypes besides an unclassified fragment), serves as a testimony to the continual divergent evolution of the virus with its approximate 1% per year rate of evolution, and this phenomena per se poses tremendous challenge for vaccine development against HIV/AIDS, a devastating disease that has killed 1.8 million patients in 2010. Here, we explore the interaction between HIV-1 and host genetic variation in the context of HIV/AIDS and antiretroviral therapy response.

Challenge of evidence in individualized medicine

Tension between standardization and individualization has always been a characteristic of medical activity. However, whether it is better that interventions should be based on guideline recommendations on the basis of large multicenter trials, or on a genetic biomarker in individualized medicine, can be the subject of debate. With the aid of stratification, evidence-based medicine and individualized medicine could be linked. Networks of large research projects, involving clinical, biomedical, molecular and other expertises are necessary for evidence-based evaluation, standardization, and clinical validation of new methods and algorithms.