Haemorrhagic colitis due to Escherichia coli O103:H2 associated with infliximab therapy in a patient with rheumatoid arthritis

[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 risk of infections with biologic therapies for rheumatoid arthritis

OBJECTIVES

To assess the risk of serious and nonserious bacterial and viral infections associated with the use of biologic therapy (abatacept, adalimumab, anakinra, etanercept, infliximab, and rituximab) in patients with rheumatoid arthritis (RA).

METHODS

Information was derived from PubMed, EMBASE, and the Cochrane clinical trials register and database of systematic reviews and relevant congress abstracts up to and including February 2008.

RESULTS

Compared with the general population, patients with RA have a heightened risk of infection, including tuberculosis. Long-term clinical trials and postmarketing studies indicate that anakinra and the tumor necrosis factor (TNF) inhibitors are associated with an increased risk of infections versus conventional disease-modifying antirheumatic drugs (DMARDs), especially early in the course of treatment. The most common sites of infection are the respiratory tract (including pneumonia), skin and soft tissue, and the urinary tract. The risk of tuberculosis also appears higher with TNF inhibitors (in particular, infliximab) versus DMARDs, although this can be reduced by screening and prophylaxis. TNF inhibitors do not appear to significantly increase the risk of reactivating chronic viral infections. Influenza and pneumococcal vaccinations are generally effective in the face of TNF inhibitors or abatacept. Available data suggest that the risk of infections and serious infections with abatacept and rituximab may be similar to that of the TNF inhibitors. To date, there have been no reports from clinical trials of increased tuberculosis or opportunistic infections with abatacept or rituximab.

CONCLUSIONS

All marketed TNF inhibitors for compared to control RA appear to increase the risk of serious and nonserious infections compared with DMARDs. Although suggestive, data for abatacept and rituximab are less definitive and longer periods of patient exposure to these agents are needed before an assessment of their risks can be made.

The non-O157 shiga-toxigenic (verocytotoxigenic) Escherichia coli; under-rated pathogens

Following a brief review of the ecology of Escherichia coli in general, the role of Shiga-Toxigenic (Verocytotoxigenic) E. coli (STEC) as pathogens is addressed. While STEC belonging to the serogroup O157 have been extensively studied and shown to be involved in many cases and outbreaks of human disease, the importance of STEC belonging to other serogroups has not been recognized as much. This review addresses the problems associated with these pathogens, demonstrating that increasing the awareness of them is a major part of the problem. This review then demonstrates how widespread isolations especially from food animals and human disease have been, discussing in particular STEC belonging to serogroups O8, O26, O103, O111, O113 and O128. The animal host-specificity of these STEC is also reviewed. In conclusion some methods of improving isolation of these pathogens is addressed.

Mycobacterium abscessus infection after use of tumor necrosis factor α inhibitor therapy: case report and review of infectious complications associated with tumor necrosis factor α inhibitor use

Tumor necrosis factor alpha (TNF-alpha) inhibitors, such as infliximab and etanercept, are now frequently used in the treatment of inflammatory diseases including rheumatoid arthritis (RA) and Crohn's disease. As an apparent result of their immune modulating activity, there has been an observed association between the use of these agents and the development of a wide range of infections, most notably Mycobacterium tuberculosis. We describe a case of infection with Mycobacterium abscessus in a 67-year-old woman receiving infliximab as a component of her therapy for RA. This case, along with extensive reports in the medical literature, illustrate how treatment with inhibitors of TNF-alpha has the potential to result in a wide range of infectious complications, including rapid growing Mycobacterium.

Infectious complications of biologic treatments of rheumatoid arthritis

Agents that block the action of tumor necrosis factor-alpha and recombinant interleukin-1 have been shown to be effective biologic treatment modalities in patients with rheumatoid arthritis. Given the immunosuppressive effects of tumor necrosis factor-alpha and interleukin-1 blockers, infections have emerged as possible complications of using these agents, an observation foreshadowed in prelicensure animal studies. At this time, hundreds of thousands of patients have received these drugs, and a wide variety of infectious complications has been reported, among which reactivation tuberculosis is most notable. Case reports alone, however, do not necessarily reflect a causal association between a therapeutic product and an adverse event. The authors review the infectious complications of the use of these agents as reported in the medical literature from November 2001 through October 2002.