Overwhelming Parasitemia with Plasmodium falciparum Infection in a Patient Receiving Infliximab Therapy for Rheumatoid Arthritis

Opportunistic tropical infections in immunosuppressed patients

Autoimmune and autoinflammatory diseases are associated with severe morbidity, and represent an impactful health and economic burden worldwide. The treatment of these diseases can include a course with detrimental side effects. Immunosuppression increases the risk of opportunistic infections, but in some cases, the abrupt discontinuation of these medications can result in immune reconstitution inflammatory syndrome. Special attention must be directed to endemic tropical infections, such as leishmaniasis, Chagas disease, malaria, arbovirosis, yellow fever, leprosy, paracoccidioidomycosis, disseminated strongyloidiasis, and ectoparasitosis. These endemic diseases of developing countries can be considered as possible emerging diseases in developed regions partially because of environmental factors and migration. In the present article, we aim to review the evidence-based aspects of the most important opportunistic tropical infections in immunosuppressed patients. We also aim to review the important aspects of vaccination, chemical prophylaxis, and treatment for these infections in people with medication-induced immunosuppression.

Reactivation of Plasmodium infection during a treatment with infliximab: A case report

We describe a symptomatic Plasmodium falciparum infection in a 29-year-old Guinean man receiving Infliximab for one year and without recent travel. The reactivation of submicroscopic malaria following the inhibition of TNF-alpha by infliximab is suspected.

Travel and biologic therapy: travel-related infection risk, vaccine response and recommendations

BACKGROUND

Biologic therapy has revolutionized the management of refractory chronic autoimmune and auto-inflammatory disease, as well as several malignancies, providing rapid symptomatic relief and/or disease remission. Patients receiving biologic therapies have an improved quality of life, facilitating travel to exotic destinations and potentially placing them at risk of a range of infections. For each biologic agent, we review associated travel-related infection risk and expected travel vaccine response and effectiveness.

METHODS

A PUBMED search [vaccination OR vaccine] AND/OR ['specific vaccine'] AND/OR [immunology OR immune response OR response] AND [biologic OR biological OR biologic agent] was performed. A review of the literature was performed in order to develop recommendations on vaccination for patients in receipt of biologic therapy travelling to high-risk travel destinations.

RESULTS

There is a paucity of literature in this area, however, it is apparent that travel-related infection risk is increased in patients on biologic therapy and when illness occurs they are at a higher risk of complication and hospitalization. Patients in receipt of biologic agents are deemed as having a high level of immunosuppression-live vaccines, including the yellow fever vaccine, are contraindicated. Inactivated vaccines are considered safe; however, vaccine response can be attenuated by the patient's biologic therapy, thereby resulting in reduced vaccine effectiveness and protection.

CONCLUSIONS

Best practice requires a collaborative approach between the patient's primary healthcare physician, relevant specialist and travel medicine expert, who should all be familiar with the immunosuppressive and immunomodulatory effects resulting from the biologic therapies. Timing of vaccines should be carefully planned, and if possible, vaccination provided well before established immunosuppression.

NASPGHAN Clinical Report: Surveillance, Diagnosis, and Prevention of Infectious Diseases in Pediatric Patients With Inflammatory Bowel Disease Receiving Tumor Necrosis Factor-α Inhibitors

Children and adolescents with inflammatory bowel disease (IBD) receiving therapy with tumor necrosis factor α inhibitors (anti-TNFα) pose a unique challenge to health care providers in regard to the associated risk of infection. Published experience in adult populations with distinct autoinflammatory and autoimmune diseases treated with anti-TNFα therapies demonstrates an increased risk of serious infections with intracellular bacteria, mycobacteria, fungi, and some viruses; however, there is a paucity of robust pediatric data. With a rising incidence of pediatric IBD and increasing use of biologic therapies, heightened knowledge and awareness of infections in this population is important for primary care pediatricians, pediatric gastroenterologists, and infectious disease (ID) physicians. This clinical report is the result of a consensus review performed by pediatric ID and gastroenterology physicians detailing relevant published literature regarding infections in pediatric patients with IBD receiving anti-TNFα therapies. The objective of this document is to provide comprehensive information for prevention, surveillance, and diagnosis of infections based on current knowledge, until additional pediatric data are available to inform evidence-based recommendations.

Management of infections in critically ill returning travellers in the intensive care unit-II: clinical syndromes and special considerations in immunocompromised patients

This position paper is the second ESCMID Consensus Document on this subject and aims to provide intensivists, infectious disease specialists, and emergency physicians with a standardized approach to the management of serious travel-related infections in the intensive care unit (ICU) or the emergency department. This document is a cooperative effort between members of two European Society of Clinical Microbiology and Infectious Diseases (ESCMID) study groups and was coordinated by Hakan Leblebicioglu and Jordi Rello for ESGITM (ESCMID Study Group for Infections in Travellers and Migrants) and ESGCIP (ESCMID Study Group for Infections in Critically Ill Patients), respectively. A relevant expert on the subject of each section prepared the first draft which was then edited and approved by additional members from both ESCMID study groups. This article summarizes considerations regarding clinical syndromes requiring ICU admission in travellers, covering immunocompromised patients.

The global pipeline of new medicines for the control and elimination of malaria

Over the past decade, there has been a transformation in the portfolio of medicines to combat malaria. New fixed-dose artemisinin combination therapy is available, with four different types having received approval from Stringent Regulatory Authorities or the World Health Organization (WHO). However, there is still scope for improvement. The Malaria Eradication Research agenda identified several gaps in the current portfolio. Simpler regimens, such as a single-dose cure are needed, compared with the current three-day treatment. In addition, new medicines that prevent transmission and also relapse are needed, but with better safety profiles than current medicines. There is also a big opportunity for new medicines to prevent reinfection and to provide chemoprotection. This study reviews the global portfolio of new medicines in development against malaria, as of the summer of 2012. Cell-based phenotypic screening, and 'fast followers' of clinically validated classes, mean that there are now many new classes of molecules starting in clinical development, especially for the blood stages of malaria. There remain significant gaps for medicines blocking transmission, preventing relapse, and long-duration molecules for chemoprotection. The nascent pipeline of new medicines is significantly stronger than five years ago. However, there are still risks ahead in clinical development and sustainable funding of clinical studies is vital if this early promise is going to be delivered.

Inflammatory bowel disease in travelers: Choosing the right vaccines and check-ups

The majority of patients with inflammatory bowel disease (IBD) achieve good control of the inflammatory activity using available therapies. When remission is achieved and quality of life recovered, a considerable proportion of IBD patients express their desire to travel abroad, be it for business, academic or leisure purposes. Their physicians should help and encourage them whenever possible. However, preventive measures are warranted to minimize the risk, since IBD patients are exposed to the same infections affecting the general population, plus opportunistic infections (OI) related to the immunosuppression. There are a large number of potential OI that might affect patients with IBD. The true prevalence of these infections is unknown, and can vary from country to country. Therefore, reactivation or de novo acquisition of infections such as tuberculosis, malaria, and viral hepatitis will be much more frequent in endemic areas. Therefore, physicians should be aware of these aspects when planning specific preventive measures for patients traveling to a particular country. This includes good control of environmental exposure, chemoprophylaxis when indicated, and the use of a specific vaccination program to prevent endemic infections. In addition, it should be noted that, though the risk of acquiring an infectious disease is probably greater for IBD patients traveling from a developed to a developing country, the inverse situation can also occur; it depends on the previous acquired immunity of the host against infections in any particular environment.

[Vaccination prior to travelling for patients with rheumatic diseases]

Rheumatologists increasingly face patient questions about the need, the safety and the effectiveness of travel-related vaccinations. Currently, there are no guidelines on travel vaccinations for patients with inflammatory rheumatic diseases. The use of live attenuated vaccines remains contraindicated in patients receiving relevant immunosuppressive therapy despite some encouraging results from initial pilot studies. However, many inactivated travel vaccines can safely be used for patients with rheumatic diseases. Furthermore, rheumatologists should be vigilant in identifying and closing gaps in the routine vaccinations for patients.

Short treatment with the tumour necrosis factor-alpha blocker infliximab diminishes chronic chagasic myocarditis in rats without evidence of Trypanosoma cruzi reactivation

Tumour necrosis factor (TNF)-alpha is crucial for resistance to Trypanosoma cruzi acute infection, but there is scant information on its role during the chronic phase. To address this issue, we analysed whether a short treatment with a TNF-alpha blocker affected the course and characteristics of chronic disease in a rat experimental model of T. cruzi infection. An anti-TNF-alpha agent (infliximab) was administered during the chronic phase for a period of 4 weeks (3 mg/kg/week), while control infected rats were inoculated with saline physiological solution. Search for parasites yielded non-successful results in all infected groups, irrespective of treatment. Nevertheless, the presence of T. cruzi kDNA in heart tissue was detected in infected and infected plus treated animals. Because infliximab might induce changes in the anti-parasite cytokine response, circulating levels of interleukin (IL)-10, interferon-gamma and nitric oxide were evaluated. An increase in IL-10 levels was observed only in the infected group treated with the anti-TNF-alpha blocker compared to the remaining groups (P < 0.05). A clear attenuation of histological damage associated with a diminution of cardiac TNF-alpha mRNA expression was observed in the infected and treated animals compared to the infected and non-treated group. Blocking of TNF-alpha during a relatively short period in chronically infected rats did not lead to evident parasite reactivation but reduced myocarditis severity significantly, indicating a role of this cytokine in the pathogenesis of chronic myocardial damage.

Parasite-dependent expansion of TNF receptor II-positive regulatory T cells with enhanced suppressive activity in adults with severe malaria

Severe Plasmodium falciparum malaria is a major cause of global mortality, yet the immunological factors underlying progression to severe disease remain unclear. CD4⁺CD25⁺ regulatory T cells (Treg cells) are associated with impaired T cell control of Plasmodium spp infection. We investigated the relationship between Treg cells, parasite biomass, and P. falciparum malaria disease severity in adults living in a malaria-endemic region of Indonesia. CD4⁺CD25⁺Foxp3⁺CD127^lo Treg cells were significantly elevated in patients with uncomplicated (UM; n = 17) and severe malaria (SM; n = 16) relative to exposed asymptomatic controls (AC; n = 10). In patients with SM, Treg cell frequency correlated positively with parasitemia (r = 0.79, p = 0.0003) and total parasite biomass (r = 0.87, p<0.001), both major determinants for the development of severe and fatal malaria, and Treg cells were significantly increased in hyperparasitemia. There was a further significant correlation between Treg cell frequency and plasma concentrations of soluble tumor necrosis factor receptor II (TNFRII) in SM. A subset of TNFRII⁺ Treg cells with high expression of Foxp3 was increased in severe relative to uncomplicated malaria. In vitro, P. falciparum–infected red blood cells dose dependently induced TNFRII⁺Foxp3^hi Treg cells in PBMC from malaria-unexposed donors which showed greater suppressive activity than TNFRII⁻ Treg cells. The selective enrichment of the Treg cell compartment for a maximally suppressive TNFRII⁺Foxp3^hi Treg subset in severe malaria provides a potential link between immune suppression, increased parasite biomass, and malaria disease severity. The findings caution against the induction of TNFRII⁺Foxp3^hi Treg cells when developing effective malaria vaccines.

Malaria is a major global health problem responsible for more than 1 million deaths annually. Severity of malaria disease is associated with the inability of host immune cells to efficiently eliminate malaria parasites from the blood. Little is known about immune regulatory factors controlling the onset of severe and potentially fatal malaria. Regulatory T (Treg) cells are a small specialized subset of immune cells that suppress the activation and expansion of effector immune cells which partake in parasite elimination. We investigated the relationship between Treg cells, parasite burden, and disease severity in adult malaria patients with either uncomplicated or severe malaria. We demonstrated that Treg cell frequency was elevated in malaria patients and associated with high parasite burden in severe malaria but not in uncomplicated malaria. Comparison of Treg cell characteristics allowed us to identify a new highly suppressive subset of Treg cells that was elevated in severe malaria patients. Our results indicate that severe malaria is accompanied by the induction of highly suppressive Treg cells that can promote parasite growth and caution against the induction of these Treg cells when developing effective malaria vaccines.

Infliximab in the treatment of plaque type psoriasis

Psoriasis is a chronic and immunomediated skin disease characterized by erythematous scaly plaques. Psoriasis affects approximately 1% to 3% of the Caucasian population. Tumor necrosis factor alpha (TNF-α) is a proinflammatory cytokine that plays a critical role in the pathogenesis of psoriasis. Infliximab is an anti-TNF-α drug widely used for the treatment of plaque type psoriasis and psoriatic arthritis. Controlled clinical trials demonstrated that infliximab is characterized by a high degree of clinical response in moderate to severe plaque psoriasis. Moreover infliximab showed rapid efficacy in nail psoriasis which represents a therapeutic challenge for dermatologists and a relevant source of distress for patients with plaque psoriasis. This anti-TNF-α has an encouraging safety profile, especially as long as physicians are watchful in prevention and early diagnosis of infections and infuse reactions. The efficacy, tolerability and safety profiles suggest infliximab as a suitable anti-psoriatic drug in the long-term treatment of a chronic disease such as plaque-type psoriasis.

Central nervous system infections in the systemic vasculitides

PURPOSE OF REVIEW

Central nervous system infections are not uncommon in systemic vasculitides. Being vigilant of central nervous system infections as an alternative consideration, instead of systemic vasculitides per se, could prove to be lifesaving in certain circumstances.

RECENT FINDINGS

Common pathogens, such as tuberculosis, Cryptococcus, and Listeria, still occur commonly as the major causes of central nervous system infection in systemic vasculitides. However, rare pathogens could be responsible among those immunocompromised hosts, and they should not be overlooked. The manifestation of central nervous system infection tends to be atypical among systemic vasculitides patients. History, physical, and cerebrospinal fluid analyses are still time-honored approaches to establishing the correct diagnosis. Newer techniques such as interferon-gamma release assay for tuberculosis, cerebrospinal fluid cytokine, or chemokine profiling need further validation and careful interpretation among such a special patient population. Immune disturbance, mainly due to immunosuppressive therapy, and polymorphism of the innate immune pathway (for example, Toll-like receptor) could be susceptibility factors for certain central nervous system infections. The biologic agents (for example, anti-tumor necrosis factor alpha, and B-cell depletion therapy) represent novel methods for treating systemic vasculitides, but they raise a critical issue owing to their increased likelihood for being associated with opportunistic infections.

SUMMARY

Despite the recent progress in this special field, the mortality of central nervous system infection in systemic vasculitides is still high, and the prognostic factors are still largely undetermined.

Targets of anticytokine therapy and the risk of infections in humans and mice

PURPOSE OF REVIEW

To examine the type and risk of infections in humans and mice deficient in proinflammatory cytokines. Naturally occurring or manipulated genetic defects of tumor necrosis factor, interleukins-1, -6, -12, and -15, and interferon-gamma are examined for their increased susceptibility to, or protection from, infection.

RECENT FINDINGS

Interleukin-12p40 and interferon-gamma-blockers may lead to increased incidence of infections with intracellular bacteria, parasites, and fungi. In addition, we may see viral infections with interferon-gamma-blockers. Increased risk of infections is unlikely with either interleukin-1- or interleukin-15-blockers. Interleukin-6-blockers may lead to increased risk of infection with extracellular bacteria, viruses, parasites and fungi.

SUMMARY

In tumor necrosis factor knockout mice, increased susceptibility to pathogens are reported that are normally controlled by granuloma formation. In patients treated with tumor necrosis factor-blockers, a two-fold increase of granulomatous infections, predominantly reactivation of latent tuberculosis, is found. The infections detected in tumor necrosis factor knockout mice were accurate for predicting the infections observed when using tumor necrosis factor-blockers. If a similar correlation exists for other cytokines, the use of interferon-gamma and interleukin-12p40 blockers, and possibly interleukin-6 blockers, will lead to an increased risk for severe infections. Care should be taken when new cytokine blockers/antagonists are introduced.

Pulmonary abnormalities in inflammatory bowel disease

Extraintestinal manifestations of inflammatory bowel disease (IBD) is a common clinical problem affecting up to half of all IBD patients; pulmonary disease, however, ranks among less common extraintestinal manifestations of IBD. Pulmonary disease in patients with IBD is most frequently drug induced due to treatment with sulfasalazine or mesalamine leading to eosinophilic pneumonia and fibrosing alveolitis or due to treatment with methotrexate leading to pneumonitis. Recently, various opportunistic infections have been shown to be a further important cause of pulmonary abnormalities in those IBD patients who are treated with immunosuppressants such as anti TNF-α monoclonal antibodies, methotrexate, azathioprine or calcineurin antagonists. In not drug related pulmonary disease a wide spectrum of disease entities ranging from small and large airway dysfunction to obstructive and interstitial lung disorders exist. Patients with lung disorders and inflammatory bowel disease should be evaluated for drug-induced lung disease and opportunistic infections prior to considering pulmonary disease as an extraintestinal manifestation of inflammatory bowel disease.