Mycobacterial Disease Attributable to Tumor Necrosis Factor–α Blockers

Genetic and Other Determinants for the Severity of Coccidioidomycosis: A Clinician's Perspective

The endemic fungal infection, coccidioidomycosis, occurs after inhalation of one or very few Coccidioides spp. spores. Infections produce diverse clinical manifestations, ranging from insignificant to extremely destructive, even fatal. Approaches to understanding this range of consequences have traditionally categorized patients into a small number of groups (asymptomatic, uncomplicated self-limited, fibro-cavitary, and extra-thoracic disseminated) and then looked for immunologic differences among them. Recently, variants within genes of innate pathways have been found to account, in part, for infections that result in disseminated disease. This discovery raises the very attractive theory that, in patients without severe immunosuppression, much of the disease spectrum can be accounted for by various combinations of such deleterious variants in innate pathways. In this review, we summarize what is known about genetic determinants that are responsible for the severity of coccidioidal infections and how complex innate genetic differences among different people might account for the spectrum of disease observed clinically.

[Infectious complications of biologic therapy in patients with rheumatoid arthritis]

The introduction of biological disease-modifying drugs (DMARDs) has substantially improved the treatment options for patients with rheumatoid arthritis. However, infectious complications represent the most common side effects of these drugs, including severe infections as well as rare opportunistic infections. Treating patients on biological DMARDs is therefore one of the biggest challenges in rheumatology care. The present review describes the current state of knowledge regarding frequency and type of infectious complications associated with biological DMARDs. The article focuses mainly on risk management, in particular on diagnosis and recurrence prevention of tuberculosis and reactivation of hepatitis B virus infection. Furthermore, we discuss the importance of vaccinations in primary disease prevention in patients with rheumatoid arthritis.

The immunology of tuberculosis: from bench to bedside

Tuberculosis (TB) is an international public health priority and kills almost two million people annually. TB is out of control in Africa due to increasing poverty and HIV coinfection, and drug-resistant TB threatens to destabilize TB control efforts in several regions of the world. Existing diagnostic tools and therapeutic interventions for TB are suboptimal. Thus, new vaccines, immunotherapeutic interventions and diagnostic tools are urgently required to facilitate TB control efforts. An improved understanding of the immunopathogenesis of TB can facilitate the identification of correlates of immune protection, the design of effective vaccines, the rational selection of immunotherapeutic agents, the evaluation of new drug candidates, and drive the development of new immunodiagnostic tools. Here we review the immunology of TB with a focus on aspects that are clinically and therapeutically relevant. An immunologically orientated approach to tackling TB can only succeed with concurrent efforts to alleviate poverty and reduce the global burden of HIV.

Infectious complications of tumor necrosis factor blockade

PURPOSE OF REVIEW

Our understanding of the infection risks posed by tumor necrosis factor (TNF) antagonists has continued to evolve in the 10 years since these drugs were first introduced. This review summarizes recent data regarding infection risk, examines potential structure-function relationships that may account for the differences, and discusses their implications with regard to tuberculosis prevention and management.

RECENT FINDINGS

Recent prospective studies have confirmed the risk of tuberculosis reactivation posed by TNF antibodies to be several fold greater than soluble TNF receptor. Certolizumab pegol, a monovalent anti-TNF Fab' fragment appears to share this risk, despite its lack of Fc and its inability to cross-link transmembrane TNF. Screening and initiation of treatment for latent tuberculosis (TB) infection can greatly reduce the TB risk of anti-TNF treatment in western countries. However, alternative strategies to prevent TB because of new transmission may be required as these therapies become available worldwide. Current recommendations for withdrawal of anti-TNF therapy when TB is diagnosed place patients at risk for paradoxical worsening because of recovery of TNF-dependent inflammation. Recent case reports suggest reinstitution of TNF blockade may be safe and effective adjunctive treatment in such cases, but prospective studies are needed to confirm these observations.

SUMMARY

TNF blockers have transformed treatment of several chronic inflammatory conditions. Further research is needed to determine how best to prevent and manage their infectious complications and to determine their potential adjunctive therapeutic role in chronic infection diseases.