Trimethoprim-sulfamethoxazole-induced Steven Johnson syndrome in an HIV-infected patient

Antibiotic prophylaxis in immunosuppressed patients - Missed opportunities from trimethoprim-sulfamethoxazole allergy label

Trimethoprim-sulfamethoxazole (TMP-SMX) is a broad spectrum antibiotic in use for more than 50 years. It has an important indication as first line agent in the prophylaxis of opportunistic infections, particularly Pneumocystis jirovecii pneumonia (PJP), in immunosuppressed patients. For those who have a history of allergy or severe intolerance to TMP-SMX, pentamidine, dapsone or atovaquone may be substituted; however there is evidence that TMP-SMX offers superior coverage for PJP, toxoplasmosis, and nocardiosis. Compared to pentamidine, it has the added benefit of cost-effectiveness and self-administration as opposed to required hospital attendance for administration. Many patients who report a history of allergy or adverse reaction to TMP-SMX (or "sulfur allergy") will be found not to be allergic; and even those who are allergic may be able to be desensitized. The evaluation and, where appropriate, removal of TMP-SMX allergy label enables the use of TMP-SMX for prophylaxis against opportunistic infections. This is a cost-effective intervention to optimize antimicrobial prescribing and reduce the risk of opportunistic infections in immunosuppressed patients.

Stevens-Johnson Syndrome (SJS) As the Initial Presentation in a Patient With a New Diagnosis of HIV

A woman in her 40s presented to the emergency department with a diffuse rash consistent with Stevens-Johnson syndrome (SJS). There was no identifiable inciting factor. However, she was newly diagnosed with human immunodeficiency virus (HIV) during that same hospital admission. The leading theory for why she developed SJS given her lack of classic precipitating factors is an immune dysregulation as a result of HIV. Most cases of SJS/toxic epidermal necrolysis (TEN) in patients with HIV are related to highly active antiretroviral therapy and prophylaxis with trimethoprim-sulfamethoxazole. There is a lack of literature regarding SJS as the initial presentation of HIV without known underlying etiology or inciting factors.

Prevention of infective complications in systemic lupus erythematosus: A systematic literature review for the APLAR consensus statements

Systemic lupus erythematosus (SLE) is a more common autoimmune rheumatic disease in the Asia-Pacific region. The prognosis of SLE remains unsatisfactory in some Asian countries because of delayed diagnosis, limited access to medications, increased complications and issues of tolerability and adherence to treatment. The Asia-Pacific League of Associations for Rheumatology SLE special interest group has recently published a set of consensus recommendations on the management of SLE for specialists, family physicians, specialty nurses, and other healthcare professionals in the Asia-Pacific region. This article reports a systematic literature review of the infective complications of SLE in Asia and evidence for prevention of these infections by pre-emptive antimicrobial therapy and vaccination.

Characterization of T-Cell Responses to SMX and SMX-NO in Co-Trimoxazole Hypersensitivity Patients Expressing HLA-B*13:01

HLA-B*13:01-positive patients in Thailand can develop frequent co-trimoxazole hypersensitivity reactions. This study aimed to characterize drug-specific T cells from three co-trimoxazole hypersensitive patients presenting with either Stevens-Johnson syndrome or drug reaction with eosinophilia and systemic symptoms. Two of the patients carried the HLA allele of interest, namely HLA-B*13:01. Sulfamethoxazole and nitroso sulfamethoxazole specific T cell clones were generated from T cell lines of co-trimoxazole hypersensitive HLA-B*13:01-positive patients. Clones were characterized for antigen specificity and cross-reactivity with structurally related compounds by measuring proliferation and cytokine release. Surface marker expression was characterized via flow cytometry. Mechanistic studies were conducted to assess pathways of T cell activation in response to antigen stimulation. Peripheral blood mononuclear cells from all patients were stimulated to proliferate and secrete IFN-γ with nitroso sulfamethoxazole. All sulfamethoxazole and nitroso sulfamethoxazole specific T cell clones expressed the CD4+ phenotype and strongly secreted IL-13 as well as IFN-γ, granzyme B and IL-22. No secretion of IL-17 was observed. A number of nitroso sulfamethoxazole-specific clones cross-reacted with nitroso dapsone but not sulfamethoxazole whereas sulfamethoxazole specific clones cross-reacted with nitroso sulfamethoxazole only. The nitroso sulfamethoxazole specific clones were activated in both antigen processing-dependent and -independent manner, while sulfamethoxazole activated T cell responses via direct HLA binding. Furthermore, activation of nitroso sulfamethoxazole-specific, but not sulfamethoxazole-specific, clones was blocked with glutathione. Sulfamethoxazole and nitroso sulfamethoxazole specific T cell clones from hypersensitive patients were CD4+ which suggests that HLA-B*13:01 is not directly involved in the iatrogenic disease observed in co-trimoxazole hypersensitivity patients.

Genetic Association of Co-Trimoxazole-Induced Severe Cutaneous Adverse Reactions Is Phenotype-Specific: HLA Class I Genotypes and Haplotypes

Co-trimoxazole (CTX) causes various forms of severe cutaneous adverse reactions (SCARs). This case-control study was conducted to investigate the involvement between genetic variants of human leukocyte antigen (HLA) and CYP2C9 in CTX-induced SCARs, including Stevens-Johnson syndrome (SJS)/toxic epidermal necrolysis (TEN) and drug reaction with eosinophilia and systemic symptoms (DRESS) in Thai patients. Thirty cases of CTX-induced SCARs were enrolled and compared with 91 CTX-tolerant controls and 150 people from the general Thai population. Cases comprised 18 SJS/TEN and 12 DRESS patients. This study demonstrated that genetic association of CTX-induced SCARs was phenotype-specific. HLA-B*15:02 and HLA-C*08:01 alleles were significantly associated with CTX-induced SJS/TEN, whereas the HLA-B*13:01 allele was significantly associated with CTX-induced DRESS. In addition, a significant higher frequency of HLA-A*11:01-B*15:02 and HLA-B*13:01-C*03:04 haplotypes were detected in the group of CTX-induced Stevens-Johnson syndrome/toxic epidermal necrolysis (SJS/TEN) and DRESS cases, respectively. Genetic association of CTX-induced SCARs is phenotype-specific. Interestingly, these association was observed only in HIV-infected patients but not in non-HIV-infected patients.

Disease of the Year 2019: Ocular Toxoplasmosis in HIV-infected Patients

Ocular toxoplasmosis (OT) may be an initial manifestation of acquired immunodeficiency syndrome (AIDS) in human immunodeficiency virus (HIV)-infected patients. OT has different clinical manifestations and can mimic other intraocular infections. Clinical findings may show single or multifocal retinochoroidal lesions or panuveitis. Atypical presentations are associated with extensive uni- or bilateral areas of retinal necrosis. OT lesions not associated with preexisting retinochoroidal scars are usually due to acquired rather than congenital infection. When CD4+ T cell counts are <100 c/uL, vitritis is frequently mild. Isolated anterior uveitis has been reported in single cases. Positive immunoglobulin M (IgM) antibodies are rare but their presence can support the diagnosis. As atypical presentations of OT are common, anterior chamber puncture for multiplex polymerase chain reaction amplification of infectious DNA should be considered, as early diagnosis and treatment can prevent massive tissue destruction and preserve vision. This review provides an overview of OT in HIV-infected patients.

Antimicrobial Desensitization: A Review of Published Protocols

Antimicrobial desensitization represents a last-line option for patients with no alternative therapies, where the benefits of this intensive process must outweigh the potential harm from drug exposure. The goal of antimicrobial desensitization procedures is to establish a temporary state of tolerance to drugs that may otherwise cause hypersensitivity reactions. While no universal antimicrobial desensitization protocols exist, this review critically analyzes previously published desensitization protocols. The purpose of this review is to provide a greater insight for clinicians and institutions to ensure desensitization procedures are efficacious while minimizing potential for patient harm. With an increasing rate of antimicrobial resistance and the critical need to preserve antimicrobial agents, desensitization may represent another option in our antimicrobial stewardship toolkit.

Presumed Sulfonamide-Associated Uveitis With Stevens-Johnson Syndrome in a Quarter Horse Mare

We describe the case of a four-year-old Quarter Horse mare that presented with fever, respiratory infection with productive cough, disorientation, and bilateral anterior uveitis with discharge that had been previously treated with trimethoprim-sulfadiazine (TMPS). Acinetobacter johnsonii was cultured from an endoscopic tracheal wash. Treatment was initiated with cefquinome, systemic flunixin-meglumine, local ocular atropine, and corticosteroids. On subsequent days, the mare exhibited bilateral edematous, painful swelling of the face, primarily affecting the eyelids and lips. There were neither swellings nor pulsations of the metatarsal arteries. On day five of treatment, the facial swelling disappeared, the uveitis improved markedly, and the mare's periorbital skin, muzzle, and vulva began to slough, revealing underlying, nonpigmented skin. Although systemic use of sulfonamides has been associated with bilateral anterior uveitis and Stevens-Johnson syndrome (SJS or erythema multiforme major) in humans, these conditions are rare in horses. Stevens-Johnson syndrome has been associated most commonly with sulfonamide use but also with a range of other medications, including anti-infectives, anti-inflammatories, anticonvulsants, analgesics, and infections. A possible pathway for sulfonamide-induced SJS is discussed. To our knowledge, this is the first reported case of sulfonamide-associated uveitis and SJS in the horse.

Dermatological conditions associated with HIV medication in a cohort of Greek patients initiating antiretroviral therapy: 1988-2013

Objectives: Treatment of HIV infection has evolved from a single antiretroviral agent to combination therapy, which has dramatically improved both the quality of life and life expectancy of affected patients. The aim of this study was to review HIV treatment-associated dermatological conditions observed in adult patients receiving antiretroviral therapy (ART) in a single tertiary care referral centre over time. Methods: We reviewed the files of HIV-positive patients seen at the Dermatology Department, AIDS Clinic of the Andreas Syggros Hospital, Athens, Greece who had initiated ART from 1988 to 2013, for evidence of dermatological conditions commonly associated with HIV-related medication. Results: Among a cohort of 1329 HIV-positive patients (1155 men and 174 women), 352 (299 men and 53 women) presented with at least one dermatological condition, with a total of 423 conditions diagnosed that could be attributed to HIV-related medication. Lipodystrophy (47.42%), and maculopapular (MP) rash (40.6%) were most commonly diagnosed. There were three incidence peaks for these reactions, which reflected the different types of ART and HIV-related drugs commonly used at the time. After 2006, the number of these dermatological conditions declined (15.1% of cases) with the availability of newer ART regimens. Conclusions: Early ART was accompanied with a high incidence of adverse skin reactions, which have decreased over time in association with overall better tolerated treatment regimens for HIV infection.

HIV-Associated Toxic Epidermal Necrolysis at San Francisco General Hospital

OBJECTIVES

We sought to characterize recent cases of toxic epidermal necrolysis (TEN) in HIV-infected patients at San Francisco General Hospital (SFGH), a large HIV referral center.

METHODS

This was a retrospective analysis of HIV-infected patients diagnosed with TEN from January 2001 to May 2014 at SFGH.

RESULTS

Ten cases of TEN were identified, 50% of which occurred in HIV-infected individuals. Among the HIV-associated cases, causative agents were trimethoprim-sulfamethoxazole (TMP-SMX; n = 2), atovaquone, clindamycin, and fluconazole. No antiretroviral agents were implicated.

CONCLUSION

Although limited by small sample size, our experience is reflective of the well-recognized increased incidence of TEN in HIV-positive patients and suggests that antimicrobial agents, particularly TMP-SMX, are the most common causative agents in this population. As 3 of the 5 HIV-associated TEN cases were caused by potentially inappropriate or unnecessary use of antibiotics, our experience highlights the importance of judicious use of systemic medications in populations susceptible to severe adverse drug reactions.

An Adverse Drug Reaction to Trimethoprim-Sulfamethoxazole Revealing Primary HIV: A Case Report and Literature Review

Adverse drug reactions (ADRs) to antibiotics complicate the management of any infection, particularly opportunistic infections in advanced HIV as some ADRs are potentiated by HIV. Trimethoprim-sulfamethoxazole (TMP-SMX) causes ADRs in 40-80% of HIV infected individuals, compared to 3-5% in the general population. The incidence and severity of ADRs among HIV infected individuals appear to increase as they progress from latent infection to AIDS. We present a single case report of a 55-year-old African American male found to have an otherwise asymptomatic acute HIV infection who developed an ADR to TMP-SMX, despite having previously tolerating the medication. The proposed mechanisms for the increased incidence of sulfa hypersensitivity reactions among HIV infected individuals focus on either (1) HIV-induced changes in the immune function driven by falling levels of CD4 cells or (2) other HIV-specific factors correlated with rising viral load. To our knowledge this is the first reported case of new sulfa hypersensitivity in primary HIV and may provide clinical evidence to support the correlation between viral load and ADRs to TMP-SMX without a severely diminished CD4 count, though further research is necessary. This case also demonstrates a rare and easily overlooked presentation of HIV that may aid in early diagnosis.

T cell receptor variable β20-1 harbors a nucleotide binding pocket in the CDR2β loop

Novel aspects of T cells containing TCRVβ20-1 are numerous, ranging from pathogen specific reactivity to specific tissue homing, or possible T cell subsets. Recently, it was demonstrated that TCR itself could become reactive by binding to small molecules free of the pHLA interface. Our work here was to identify a natural ligand binding to an identified pocket on the CDR2β loop of these TCR. Using docking of suspected ligands, we were able to show Guanine and Adenine di- and tri-nucleotides readily bind to the identified site. Comparing these with small molecule sites found on other TCR types, we show this interaction is novel. With further molecular dynamic simulations, these sites are shown to be plausible by conducting simple computational based solubility tests as cross validation. Combined with simple proliferative responses, the identified nucleotides are also shown to have functional consequences by inducing T cell proliferation for CD4/Vβ20-1 + T cells, while failing to induce proliferation in other T cell isolates. Merging computational and simple cell assays, this work establishes a role of nucleotides in T cells found to contain this TCR sub-type.