Immune reconstitution inflammatory syndrome

Graves' Disease in a Patient With Human Immunodeficiency Virus Infection as an Immune Reconstitution Inflammatory Syndrome

The use of highly active antiretroviral therapy (HAART) in the management and treatment of human immunodeficiency virus type 1 (HIV-1) has dramatically changed the course of the disease and improved overall survival. HAART results in significant decrease in viral load and enhancement of CD4 cells and gradual restoration of the immune system. However, a subset of patients may experience a paradoxical worsening after the initiation of HAART due to a heightened and dysregulated immune response. This phenomenon is termed immune reconstitution inflammatory syndrome (IRIS). The manifestation of Graves’ disease (GD) after the introduction of HAART has been identified as IRIS manifestation in some patients. Thus, this occurrence should be suspected and further investigated in patients with HIV on antiretroviral therapy (ART) who present with symptoms consistent of hyperthyroidism to avoid overt hyperthyroidism. We report a case of IRIS associated Graves’ disease. Our case adds to the very limited literature about this phenomenon. 

Antimicrobial Therapy in the Context of the Damage-Response Framework: the Prospect of Optimizing Therapy by Reducing Host Damage

By design, antimicrobial agents act directly on microbial targets. These drugs aim to eliminate microbes and are remarkably effective against susceptible organisms. Nonetheless, some patients succumb to infectious diseases despite appropriate antimicrobial therapy. Today, with very few exceptions, physicians select antimicrobial therapy based on its activity against the targeted organism without consideration of how the regimen affects patients' immune responses. An important concept to emerge in the past few decades is that immune responses to microbes can be detrimental by enhancing host damage, which can translate into clinical disease. A central tenet of the damage-response framework (DRF) of microbial pathogenesis is that the relevant outcome of host-microbe interaction is the damage that occurs in the host, which can be due to microbial factors, host factors, or both. Given that host damage can make patients sick, reducing it should be a goal of treating infectious diseases. Inflammation and damage that stem from the host response to an infectious disease can increase during therapy with some antimicrobial agents and decrease during therapy with others. When a patient cannot eliminate a microbe with their own immune response, antimicrobial therapy is essential for microbial elimination, and yet it can affect the inflammatory response. In this essay, we discuss antimicrobial therapy in the context of the DRF and propose that consideration of the DRF may help tailor therapy to a patient's need to augment or reduce inflammation.

Opportunistic infection at the start of antiretroviral therapy and baseline CD4+ count less than 50 cells/mm3 are associated with poor immunological recovery

Introduction There is a dearth of studies assessing the efficacy and immunological improvement in patients started on antiretroviral therapy (ART) in India. This study was undertaken to assess the 2-year treatment outcomes in HIV-positive patients initiated on ART in a tertiary-care hospital. Methods After approval from the Institutional Ethics Committee, adult HIV-positive patients from a tertiary-care hospital, initiated on ART between January 2013 and February 2015, were included in the study. Data on clinical and immunological parameters were obtained from medical case records over a period of 2 years after initiation of therapy. Intention-to-treat analysis was done using a descriptive approach, using SPSS version 15 (SPSS Inc. Released 2006. SPSS for Windows, Version 15.0. Chicago, SPSS Inc.). A logistic regression analysis was done to assess the predictors for poor outcomes. A p-value <0.05 was considered statistically significant. Results ART was initiated in 299 adult patients. At 1 and 2 years, the median (interquartile range) change in CD4+ cell count was 65 (39, 98) cells/mm3 and 160 (95, 245) cells/mm3. The change observed after 2 years of treatment initiation was statistically significant compared with that after 1 year. Three deaths occurred during the study period and 28 were lost to follow-up. Male sex, presence of at least one opportunistic infection at the start of therapy, and baseline CD4+ count <50 cells/mm3 were associated with poor immunological recovery. Conclusions With long-term treatment and regular follow-up, sustained clinical and immunological outcomes can be obtained in resource-limited settings.

Fungal Diseases in the 21st Century: The Near and Far Horizons

Fungal diseases became a major medical problem in the second half of the 20th century when advances in modern medicine together with the HIV epidemic resulted in large numbers of individuals with impaired immunity. Fungal diseases are difficult to manage because they tend to be chronic, hard to diagnose, and difficult to eradicate with antifungal drugs. This essay considers the future of medical mycology in the 21st century, extrapolating from current trends. In the near horizon, the prevalence of fungal diseases is likely to increase, as there will be more hosts with impaired immunity and drug resistance will inevitably increase after selection by antifungal drug use. We can expect progress in the development of new drugs, diagnostics, vaccines, and immunotherapies. In the far horizon, humanity may face new fungal diseases in association with climate change. Some current associations between chronic diseases and fungal infections could lead to the establishment of fungi as causative agents, which will greatly enhance their medical importance. All trends suggest that the importance of fungal diseases will increase in the 21st century, and enhanced human preparedness for this scourge will require more research investment in this group of infectious diseases.

Management of Human Immunodeficiency Virus in the Emergency Department

Over the past 30 years, significant advances have transformed the landscape of human immunodeficiency virus (HIV) care in the emergency department. Diagnosis and management of HIV has improved, resulting in a decline in the incidence of acquired immunodeficiency syndrome (AIDS)-defining infections. Advances in pharmacology have led to fewer serious medication toxicities and more tolerable regimens. Emergency providers have played an increasingly important role in HIV screening and diagnosis of acute infection. Provision of postexposure prophylaxis is expanding from a focus on occupational exposure to include all high-risk cases.

Mechanisms of Cryptococcus neoformans-Mediated Host Damage

Cryptococcus neoformans is not usually considered a cytotoxic fungal pathogen but there is considerable evidence that this microbe can damage host cells and tissues. In this essay, we review the evidence that C. neoformans damages host cells and note that the mechanisms involved are diverse. We consider C. neoformans-mediated host damage at the molecular, cellular, tissue, and organism level. Direct mechanisms of cytotoxicity include lytic exocytosis, organelle dysfunction, phagolysosomal membrane damage, and cytoskeletal alterations. Cytotoxicity contributes to pathogenesis by interfering with immune effector cell function and disrupting endothelial barriers thus allowing dissemination. When C. neoformans-mediated and immune-mediated host damage is sufficient to affect homeostasis, cryptococcosis occurs at the organism level.

Paradoxical and bidirectional drug effects

A paradoxical drug reaction constitutes an outcome that is opposite from the outcome that would be expected from the drug's known actions. There are three types: 1. A paradoxical response in a condition for which the drug is being explicitly prescribed. 2. Paradoxical precipitation of a condition for which the drug is indicated, when the drug is being used for an alternative indication. 3. Effects that are paradoxical in relation to an aspect of the pharmacology of the drug but unrelated to the usual indication. In bidirectional drug reactions, a drug may produce opposite effects, either in the same or different individuals, the effects usually being different from the expected beneficial effect. Paradoxical and bidirectional drug effects can sometimes be harnessed for benefit; some may be adverse. Such reactions arise in a wide variety of drug classes. Some are common; others are reported in single case reports. Paradoxical effects are often adverse, since they are opposite the direction of the expected effect. They may complicate the assessment of adverse drug reactions, pharmacovigilance, and clinical management. Bidirectional effects may be clinically useful or adverse. From a clinical toxicological perspective, altered pharmacokinetics or pharmacodynamics in overdose may exacerbate paradoxical and bidirectional effects. Certain antidotes have paradoxical attributes, complicating management. Apparent clinical paradoxical or bidirectional effects and reactions ensue when conflicts arise at different levels in self-regulating biological systems, as complexity increases from subcellular components, such as receptors, to cells, tissues, organs, and the whole individual. These may be incompletely understood. Mechanisms of such effects include different actions at the same receptor, owing to changes with time and downstream effects; stereochemical effects; multiple receptor targets with or without associated temporal effects; antibody-mediated reactions; three-dimensional architectural constraints; pharmacokinetic competing compartment effects; disruption and non-linear effects in oscillating systems, systemic overcompensation, and other higher-level feedback mechanisms and feedback response loops at multiple levels. Here we review and provide a compendium of multiple class effects and individual reactions, relevant mechanisms, and specific clinical toxicological considerations of antibiotics, immune modulators, antineoplastic drugs, and cardiovascular, CNS, dermal, endocrine, musculoskeletal, gastrointestinal, haematological, respiratory, and psychotropic agents.

Secondary Buruli ulcer skin lesions emerging several months after completion of chemotherapy: paradoxical reaction or evidence for immune protection?

Background

The neglected tropical disease Buruli ulcer (BU) caused by Mycobacterium ulcerans is an infection of the subcutaneous tissue leading to chronic ulcerative skin lesions. Histopathological features are progressive tissue necrosis, extracellular clusters of acid fast bacilli (AFB) and poor inflammatory responses at the site of infection. After the recommended eight weeks standard treatment with rifampicin and streptomycin, a reversal of the local immunosuppression caused by the macrolide toxin mycolactone of M. ulcerans is observed.

Methodology/Principal Findings

We have conducted a detailed histopathological and immunohistochemical analysis of tissue specimens from two patients developing multiple new skin lesions 12 to 409 days after completion of antibiotic treatment. Lesions exhibited characteristic histopathological hallmarks of Buruli ulcer and AFB with degenerated appearance were found in several of them. However, other than in active disease, lesions contained massive leukocyte infiltrates including large B-cell clusters, as typically found in cured lesions.

Conclusion/Significance

Our histopathological findings demonstrate that the skin lesions emerging several months after completion of antibiotic treatment were associated with M. ulcerans infection. During antibiotic therapy of Buruli ulcer development of new skin lesions may be caused by immune response-mediated paradoxical reactions. These seem to be triggered by mycobacterial antigens and immunostimulators released from clinically unrecognized bacterial foci. However, in particular the lesions that appeared more than one year after completion of antibiotic treatment may have been associated with new infection foci resolved by immune responses primed by the successful treatment of the initial lesion.

Buruli ulcer (BU) is a chronic necrotizing skin disease presenting with extensive tissue destruction and local immunosuppression. Standard treatment recommended by the WHO includes 8 weeks of rifampicin/streptomycin and, if necessary, wound debridement and skin grafting. In some patients satellite lesions develop close to the primary lesion or occasionally also at distant sites during effective antibiotic treatment of the primary lesion. We performed a detailed analysis of tissue specimens from lesions that emerged in two BU patients from Benin 12 to 409 days after completion of chemotherapy. Histopathology revealed features of tissue destruction typically seen in BU and degenerated acid-fast bacilli. In addition, lesions contained organized immune infiltrates typically found in successfully treated BU lesions. Secondary lesions emerging many months after completion of chemotherapy may have been caused by immune response-mediated paradoxical reactions. However, the late onset may also indicate that they were associated with new infection foci spontaneously resolved by adaptive immune responses primed by antibiotic treatment of the primary lesions.

Graves' Disease as a Manifestation of Immune Reconstitution in HIV-Infected Individuals after Initiation of Highly Active Antiretroviral Therapy

Graves' disease after the initiation of highly active antiretroviral therapy (HAART) in certain HIV-1-infected individuals has been described as an immune reconstitution inflammatory syndrome (IRIS). This phenomenon should be suspected in individuals who present with clinical deterioration and a presentation suggestive of hyperthyroidism despite good virological and immunological response to HAART. Signs and symptoms of hyperthyroidism may be discrete or overt and typically develop 8–33 months after initiating therapy. One to two percent of HIV-infected patients can present with overt thyroid disease. Relatively few cases of Graves' IRIS have been reported in the literature to date. We describe four cases of Graves' IRIS in HIV-infected patients who were started on HAART therapy.

Immunostimulation in the era of the metagenome

Microbes are increasingly being implicated in autoimmune disease. This calls for a re-evaluation of how these chronic inflammatory illnesses are routinely treated. The standard of care for autoimmune disease remains the use of medications that slow the immune response, while treatments aimed at eradicating microbes seek the exact opposite-stimulation of the innate immune response. Immunostimulation is complicated by a cascade of sequelae, including exacerbated inflammation, which occurs in response to microbial death. Over the past 8 years, we have collaborated with American and international clinical professionals to research a model-based treatment for inflammatory disease. This intervention, designed to stimulate the innate immune response, has required a reevaluation of disease progression and amelioration. Paramount is the inherent conflict between palliation and microbicidal efficacy. Increased microbicidal activity was experienced as immunopathology-a temporary worsening of symptoms. Further studies are needed, but they will require careful planning to manage this immunopathology.