Nontuberculous mycobacterial immune reconstitution syndrome in HIV-infected patients: spectrum of disease and long-term follow-up

"How do I manage disseminated Mycobacterium avium complex (MAC) disease in people with HIV?"

BACKGROUND

Advanced HIV disease (AHD) is increasing, with late presentation accounting for half of newly diagnosed people with HIV (PWH) in Europe. Mortality in late-presenting PWH remains high, and Mycobacterium avium complex (MAC) disease, among other opportunistic infections, presents several diagnostic and treatment challenges that lead, ultimately, to a poor clinical outcome.

OBJECTIVES

We aimed to provide guidance on the diagnosis and treatment of disseminated MAC disease (dMACd) in PWH.

SOURCES

We performed a review of original articles, meta-analyses, and systematic reviews retrieved from PubMed.

CONTENT

We reviewed and discussed the most challenging steps in the management of PWH with AHD and dMACd: the current epidemiology in the era of effective antiretroviral treatment (ART); clinical presentation and interpretation of symptoms in the context of other opportunistic infections and immune reconstitution; diagnosis, sampling, and timing to reach a definitive diagnosis; prophylaxis, treatment options, and indications for discontinuing MAC treatment; future perspectives, and the role of rifamycins in the treatment of dMACd.

IMPLICATIONS

Despite the widespread availability of effective ART, dMACd still represents a major cause of morbidity and mortality in PWH with AHD. Residual challenges are mainly related to the difficulties and timing required to reach a definitive diagnosis, and the discussion regarding the role of rifamycins in the treatment of dMACd is still open.

Immune Reconstitution Syndrome Caused by Nontuberculous Mycobacteria: A Case Report and Review of Literature

Immune reconstitution inflammatory syndrome (IRIS) is a potentially life-threatening phenomenon associated with the initiation of antiretroviral therapy in patients with acquired immunodeficiency syndrome due to a human immunodeficiency virus (HIV) infection. It is thought to be an exaggerated inflammatory response to an existing pathogen or even its antigen. We present a case of IRIS due to a non-tuberculous mycobacteria infection in a young patient with HIV infection who was recently started on therapy. This case highlights the challenges of making such a diagnosis and the importance of multidisciplinary team discussions with pulmonary and infectious diseases for optimal management of these patients.

Antiretroviral Stewardship: Top 10 Questions Encountered by Stewardship Teams and Solutions to Optimize Therapy

PURPOSE

Infectious disease pharmacists and physicians overseeing antimicrobial stewardship programs possess expertise and often advanced certification in management of antiretrovirals to treat HIV. Stewardship programs are responsible for managing facility formularies and must stay up to date with the latest antiretrovirals, including once daily formulations and depot injectables. Furthermore, stewardship program members need to understand drug-interactions, short-, and long-term toxicities of these regimens, including dyslipidemia and cardiovascular effects. Patients receiving chronic antiretroviral therapy may present to the acute care, ambulatory care, and long-term care settings. Like other antimicrobials, audit-and-feedback, drug monitoring, and dose-optimization are often required to prevent antiretroviral associated medication errors and minimize resistance.

METHODS

A narrative review was conducted on antiretroviral stewardship, addressing common clinical questions encountered by stewardship teams and best practices to optimize antiretroviral therapy and reduce the risk for treatment interruptions, resistance, drug interactions, long term toxicities, and other adverse effects.

FINDINGS

People living with HIV are often hospitalized and treated by medical teams without formal HIV training. For this reason, these patients are at greater risk for medication errors during hospitalization and between transitions of care. Many opportunities are present for antiretroviral stewardship to mitigate these errors. Frequent updates to simplify HIV regimen, maintain select patients on fixed-dose combination tablets, and strategies to minimize drug interactions make it difficult for even the seasoned clinician to keep up regularly.

IMPLICATIONS

Despite the availability of free online HIV resources and progress made in HIV management, significant opportunities for antiretroviral stewardship remain. Implementing electronic order entry updates, formulary upgrades, and formal pharmacy renal dose adjustments to optimize antiretroviral therapy will help clinicians harness these opportunities. Dedicated time and expertise for antiretroviral stewardship as part of local antimicrobial stewardship programs are needed.

Overlap Syndrome of Immune Reconstitution Inflammatory Syndrome Secondary to Disseminated Mycobacterial Infection and Hemophagocytic Lymphohistiocytosis in a Patient With Newly Diagnosed HIV/AIDS

Immune reconstitution inflammatory syndrome (IRIS) following initiation of antiretroviral therapy (ART) has variable incidence but is not uncommon and has the potential to cause long-term consequences and fatal outcomes in patients with HIV. Hemophagocytic lymphohistiocytosis (HLH) is a separate syndrome of excess immune activation, but may coexist with IRIS and necessitate a unique treatment approach. In this report, the case of a patient with newly diagnosed HIV/AIDS who was found to have both mycobacterial IRIS and HLH is presented.

Nontuberculous Mycobacterial Pulmonary Disease in the Immunocompromised Host

The immunocompromised host is at an increased risk for pulmonary and extrapulmonary NTM infections. Where data are available in these specific populations, increased mortality is observed with NTM disease. Prior to starting therapy for NTM disease, providers should ensure diagnostic criteria are met as treatment is long and often associated with significant side effects and toxicities. Treatment should involve 2 to 4 agents and be guided by cultures and antimicrobial susceptibilities. Drug interactions are important to consider, especially in those with HIV or transplant recipients. Whenever possible, immunosuppression should be reduced or changed.

Chylothorax: A Late Complication of Disseminated Mycobacterium avium Complex (MAC) Infection

Chylothorax is a rare cause of pleural effusion and occurs due to leakage of chyle into the pleural space. In most cases, it results from trauma, with malignancy accounting for most of the non-traumatic causes. Chylothorax resulting from immune reconstitution inflammatory syndrome (IRIS), during treatment of Mycobacterium avium complex (MAC) infection, is an extremely infrequent cause of chylothorax, with only a handful of cases reported in the literature.

Immune Reconstitution Inflammatory Syndrome Induced by Mycobacterium avium Complex Infection Presenting as Chronic Inflammatory Demyelinating Polyneuropathy in a Young AIDS Patient

Antiretroviral therapy (ART) can restore protective immune responses against opportunistic infections (OIs) and reduce mortality in patients with human immunodeficiency virus (HIV) infections. Some patients treated with ART may develop immune reconstitution inflammatory syndrome (IRIS). Mycobacterium avium complex (MAC)-related IRIS most commonly presents as lymphadenitis, soft-tissue abscesses, and deteriorating lung infiltrates. However, neurological presentations of IRIS induced by MAC have been rarely described. We report the case of a 31-year-old man with an HIV infection. He developed productive cough and chronic inflammatory demyelinating polyneuropathy (CIDP) three months after the initiation of ART. He experienced an excellent virological and immunological response. Sputum culture grew MAC. The patient was diagnosed with MAC-related IRIS presenting as CIDP, based on his history and laboratory, radiologic, and electrophysiological findings. Results: Neurological symptoms improved after plasmapheresis and intravenous immunoglobulin (IVIG) treatment. To our knowledge, this is the first reported case of CIDP due to MAC-related IRIS. Clinicians should consider MAC-related IRIS in the differential diagnosis of CIDP in patients with HIV infections following the initiation of ART.

Clinical and Immunologic Predictors of Mycobacterium avium Complex Immune Reconstitution Inflammatory Syndrome in a Contemporary Cohort of Patients With Human Immunodeficiency Virus

BACKGROUND

People with human immunodeficiency virus (HIV) can present with new or worsening symptoms associated with Mycobacterium avium complex (MAC) infection shortly after antiretroviral therapy (ART) initiation as MAC immune reconstitution inflammatory syndrome (MAC-IRIS). In this study, we assessed the utility of several laboratory tests as predictors of MAC-IRIS.

METHODS

People with HIV with clinical and histologic and/or microbiologic evidence of MAC-IRIS were identified and followed up to 96 weeks post-ART initiation within a prospective study of 206 ART-naive patients with CD4 <100 cells/µL.

RESULTS

Fifteen (7.3%) patients presented with MAC-IRIS within a median interval of 26 days after ART initiation. Patients who developed MAC-IRIS had lower body mass index, lower hemoglobin levels, higher alkaline phosphatase (ALP), and increased CD38 frequency and mean fluorescence intensity on CD8+ T cells at the time of ART initiation compared with non-MAC IRIS patients. A decision tree inference model revealed that stratifying patients based on levels of ALP and D-dimer could predict the likelihood of MAC-IRIS. A binary logistic regression demonstrated that higher levels of ALP at baseline were associated with increased risk of MAC-IRIS development.

CONCLUSIONS

High ALP levels and increased CD8+ T-cell activation with low CD4 counts at ART initiation should warrant suspicion for subsequent development of MAC-IRIS.

Care of Critically Ill Patients with Human Immunodeficiency Virus

Care of patients with human immunodeficiency virus (HIV) infection in the intensive care unit (ICU) has changed dramatically since the infection was first recognized in the United States in 1981. The purpose of this review is to describe the current important aspects of care of patients with HIV infection in the ICU, with a primary focus on the United States and developed countries. The epidemiology and initial approach to diagnosis and treatment of HIV (including the newest antiretroviral guidelines), common syndromes and their management in the ICU, and typical comorbidities and opportunistic infections of patients with HIV infection are discussed.

HIV Lymphadenopathy: Differential Diagnosis and Important Imaging Features

OBJECTIVE. The purpose of this article is to review important imaging and clinical features to help elucidate causes of lymphadenopathy in patients with HIV infection. CONCLUSION. HIV lymphadenopathy has various causes generally categorized as inflammatory or reactive, such as immune reconstitution syndrome; infectious, such as tuberculous and nontuberculous mycobacterial infections and HIV infection itself; and neoplastic, such as lymphoma, Kaposi sarcoma, and Castleman disease. It is important to consider patients' demographic characteristics, clinical presentations, CD4 lymphocyte counts, and radiologic features to identify likely causes of lymphadenopathy.

Antiretroviral therapy-induced paradoxical worsening of previously healed Mycobacterium haemophilum cutaneous lesions in advanced HIV infection

Mycobacterium haemophilum is a nontuberculous mycobacterium that causes localized or disseminated disease, mainly in immunocompromised hosts. We report the case of a 35-year-old HIV-infected woman who presented with several enlarging cutaneous lesions over the arms and legs. Histopathological examination revealed the diagnosis of a cutaneous mycobacterial disease. Mycobacterial analyses unveiled M. haemophilum infection. Six months after completion of a successful antimycobacterial treatment, she developed an immune reconstitution inflammatory syndrome (IRIS). This paradoxical relapse presented as tenderness, redness and swelling at the precise sites of the healed lesions and took place in the setting of significant recovery of the CD4 cell count (from 05 to 318 cells/mm 3 ). Microbiological analyses of these worsening lesions were negative, and they spontaneously remitted without the initiation of a novel antimycobacterial treatment cycle. M. haemophilum infection should always be considered as a cause of skin lesions in immunocompromised subjects. Physicians should be aware of the possibility of IRIS as a complication of successful antiretroviral therapy in HIV-infected patients with M. haemophilum infection.

Intramedullary spinal cord lesions in an immunocompromised host due to Mycobacterium haemophilum

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M. haemophilum can produce severe disease in persons living with HIV/AIDS or other immunocompromised patients.

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The spectrum of disease caused by M. haemophilum may produce life-threatening central nervous system disease.

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The treatment of M. haemophilum when involving the CNS is challenging requiring multi-drug therapy.

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Patients with M. haemophilum central nervous system disease, with and without HIV, should be monitored for IRIS.

Mycobacterium haemophilum is a slow growing acid-fast bacillus (AFB) in the nontuberculous mycobacteria (NTM) group. M. haemophilum typically causes cervicofacial lymphadenitis in children, cutaneous diseases, septic arthritis and osteomyelitis. However, it rarely causes isolated spinal cord disease. We report the first case, to our knowledge, of isolated intramedullary spinal lesions secondary to M. haemophilum. This case involved a patient with newly diagnosed human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS). He developed significant immune reconstitution inflammatory syndrome (IRIS) during his treatment. M. haemophilum should be on the differential for isolated intramedullary spinal lesions, particularly in immunocompromised patients. Given our patient’s severe IRIS, patients with HIV and M. haemophilum infection should be closely monitored for IRIS and treated aggressively. In high risk circumstances such as M. haemophilum spinal disease in patients with HIV, clinicians should consider pre-emptive treatment for IRIS.

International Society of Cardiovascular Infectious Diseases Guidelines for the Diagnosis, Treatment and Prevention of Disseminated Mycobacterium chimaera Infection Following Cardiac Surgery with Cardiopulmonary Bypass

Mycobacterial infection-related morbidity and mortality in patients following cardiopulmonary bypass surgery is high and there is a growing need for a consensus-based expert opinion to provide international guidance for diagnosing, preventing and treating in these patients. In this document the International Society for Cardiovascular Infectious Diseases (ISCVID) covers aspects of prevention (field of hospital epidemiology), clinical management (infectious disease specialists, cardiac surgeons, ophthalmologists, others), laboratory diagnostics (microbiologists, molecular diagnostics), device management (perfusionists, cardiac surgeons) and public health aspects.

Emergence of Polyfunctional Cytotoxic CD4+ T Cells in Mycobacterium avium Immune Reconstitution Inflammatory Syndrome in Human Immunodeficiency Virus-Infected Patients

Background

Immune reconstitution inflammatory syndrome (IRIS) is an aberrant inflammatory response in individuals with advanced human immunodeficiency virus (HIV) infection, after antiretroviral therapy (ART) initiation. The pathogenesis of Mycobacterium avium complex (MAC)-associated IRIS has not been fully elucidated.

Methods

We investigated monocyte and CD4+ T-cell responses in vitro, tumor necrosis factor (TNF) expression in tissues, and plasma cytokines and inflammatory markers, in 13 HIV-infected patients with MAC-IRIS and 14 HIV-uninfected patients with pulmonary MAC infection.

Results

Prior to ART, HIV-infected compared with HIV-uninfected patients, had reduced TNF+ monocytes (P = .013), although similar cytokine (interferon gamma [IFN-γ], TNF, interleukin 2 [IL-2], and interleukin 17 [IL-17])-expressing CD4+ T cells. During IRIS, monocyte cytokine production was restored. IFN-γ+ (P = .027), TNF+ (P = .004), and polyfunctional CD4+ T cells (P = 0.03) also increased. These effectors were T-betlow, and some expressed markers of degranulation and cytotoxic potential. Blockade of cytotoxic T-lymphocyte associated protein 4 and lymphocyte activation gene-3 further increased CD4+ T-cell cytokine production. Tissue immunofluorescence showed higher proportions of CD4+ and CD68+ (monocyte/macrophage) cells expressed TNF during IRIS compared with HIV-uninfected patients. Plasma IFN-γ (P = .048), C-reactive protein (P = .008), and myeloperoxidase (P < .001) levels also increased, whereas interleukin 10 decreased (P = .008) during IRIS.

Conclusions

Advanced HIV infection was associated with impaired MAC responses. Restoration of monocyte responses and expansion of polyfunctional MAC-specific T-betlow CD4+ T cells with cytotoxic potential after ART initiation may overwhelm existing regulatory and inhibitory mechanisms, leading to MAC-IRIS.

Large abscess formed in the abdominal wall by Mycobacterium avium complex: A case of unmasking immune reconstitution inflammatory syndrome

Immune reconstitution inflammatory syndrome (IRIS) is a clinical entity with a broad presentation that is complicated in patients with acquired immunodeficiency syndrome after initiating antiretroviral therapy. A 51-year-old Japanese man was diagnosed with disseminated Mycobacterium avium complex (MAC) infection presenting as unmasking IRIS, which formed a large abscess in the patient's abdominal wall. MAC-IRIS commonly involves the lymph nodes, bone marrow, and gastrointestinal tract. To our knowledge, this is the first case report of an abdominal wall abscess caused by MAC-IRIS.

Management of Advanced HIV Disease

Great progress has been made in caring for persons with human immunodeficiency virus. However, a significant proportion of individuals still present to care with advanced disease and a low CD4 count. Careful considerations for selection of antiretroviral therapy as well as close monitoring for opportunistic infections and immune reconstitution inflammatory syndrome are vitally important in providing care for such individuals.

Imaging of Pulmonary Infections

Pulmonary infections have always been a cause of high morbidity and mortality, particularly in the pediatric and geriatric population and in immunocompromised hosts [1]. Pulmonary infections have various etiologies and have variegated patterns on radiographs and computed tomography (CT). Imaging plays an important role in the initial diagnosis and follow-up of various lung infections. Radiographs can be normal or non-specific during the initial evaluation, and CT findings may be more definitive. CT not only helps with the diagnosis but can also aid in management by guiding the diagnostic and therapeutic procedure. The pulmonary infections spread by direct or indirect contact with the infected host, droplet transmission, or an airborne spread. In rare cases, some infections can also be transmitted by vectors, namely, insect or animal hosts, and rarely by direct invasion from nearby infected organs. Pulmonary infections may have typical imaging patterns and distribution based on the mode of spread. There are a number of well-described imaging patterns of alveolar infections. The localization and morphological features on imaging may help in the diagnosis of infection and identification of mode of infection and, in certain cases, the microorganism responsible for the infection.

Cutaneous Infections Due to Nontuberculosis Mycobacterium: Recognition and Management

Nontuberculous mycobacteria (NTM) are a diverse group of organisms that are ubiquitous in the environment, and the incidence of cutaneous infections due to NTM has been steadily increasing. Cutaneous infections due to NTM can be difficult to diagnose, due to their wide spectrum of clinical presentations and histopathological findings that are often nonspecific. A variety of modalities including tissue culture and polymerase chain reaction (PCR) assays may be necessary to identify the organism. Treatment can also be challenging, as it can depend on multiple factors, including the causative organism, the patient's immunological status, and the extent of disease involvement. In this review, we discuss the common presentations of cutaneous NTM infections, diagnostic tools, and treatment recommendations. A multi-disciplinary approach that involves good communication between the clinician, the histopathologist, the microbiologist, and infectious disease specialists can help lead to successful diagnosis and management.

High mortality in peritonitis due to Mycobacterium avium complex: retrospective study and systematic literature review

BACKGROUND

Mycobacterium avium complex (MAC) infection is often disseminated and mainly involves lymph nodes, spleen, liver or bone marrow. Peritonitis due to MAC infection (PMAC) is a very uncommon manifestation.

METHODS

In this report, after describing the case of the only PMAC infection in our 10-year retrospective study, which occurred in an AIDS patient who was non-adherent to highly active antiretroviral therapy (HAART), we performed a systematic literature review of documented bacteriological PMAC.

RESULTS

Including our patient, 51 cases of PMAC have been reported. Patients were most often male (sex ratio 2.14), with a median age of 41 years (2.8-72) and an immunodeficiency in all cases, most often AIDS (57%), cirrhosis (20%) and continuous ambulatory peritoneal dialysis (CAPD) (18%). Ascites was more often chylous (54%) than exudative (46%) and, in this case, lymphocytic (60%), with an inconstantly positive acid-fast bacilli smear (54%). Non-disseminated PMAC patients were more likely to have peritoneal dialysis (39% versus 6.5%, p < .01) or cancer with immunosuppressive therapy (39% versus 0%, p < .0001), while AIDS was the leading underlying disease in disseminated-PMAC patients (83% versus 11%, p < .001). Mortality was high (50%), with no difference between disseminated and non-disseminated PMAC.

CONCLUSIONS

This report highlights the need to be aware of an atypical presentation of PMAC infection, which is associated with a high rate of mortality even for non-disseminated infection.

Mycobacterium avium Complex Infection-Related Immune Reconstitution Inflammatory Syndrome Mimicking Lymphoma in an Human Immunodeficiency Virus-Infected Patient

In acquired immunodeficiency syndrome (AIDS) patients, immune reconstitution inflammatory syndrome (IRIS) due to Mycobacterium avium complex (MAC) infection is one of the most difficult IRIS types to manage. We report an unusual case of MAC-associated IRIS. At first the patient was diagnosed human immunodeficiency virus (HIV) infection after he was admitted with pneumocystis pneumonia. After starting antiretroviral therapy he presented unmasked IRIS with MAC infection. Next, he was hospitalized with continuous loose stools and new-onset fever. Investigation included computed tomography (CT), which showed homogeneous enhancement and enlargement of the lymph nodes (LN), elevation of ferritin (>1,650 ng/mL) and lactate dehydrogenase (306 IU/L) levels, and F- fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) scan, which showed increased FDG uptake. These findings were highly indicative of lymphoma. We performed laparoscopic biopsy of the mesenteric LN, and the biopsy culture grew MAC. So we made a diagnosis of MAC-associated. Therefore, IRIS must be considered as a possible diagnosis when AIDS patients develop new symptoms or exhibit exacerbations of existing symptoms. Furthermore the biopsies should be conducted.

Immune Reconstitution Inflammatory Syndrome in children

Immune Reconstitution Inflammatory Syndrome (IRIS) refers to a collection of inflammatory disorders, predominantly related to infectious processes that manifest after the initiation of antiretroviral therapy (ART) and can be classified as unmasking or paradoxical. The prevalence of IRIS in children in sub-Saharan Africa is low. Approximately half of all cases are associated with Mycobacterium tuberculosis. It may be difficult to distinguish IRIS from tuberculosis and other opportunistic infections radiologically; therefore, radiological findings must be interpreted with clinical and laboratory findings. In this review article, we describe the clinical and radiological manifestations of IRIS in children and provide illustrative radiological examples.

[Immune reconstitution inflammatory syndrome and rebound syndrome in multiple sclerosis patients who stopped disease modification therapy: current understanding and a case report]

More and more multiple sclerosis patients have been receiving treatment with new immunomodulatory drugs. Its discontinuation because of side-effects, lack of efficacy or pregnancy has been increasing as well. This paper reviews such severe complications of natalizumab and fingolimod cessation as immune reconstitution inflammatory syndrome (IRIS) and rebound. The short history, immunopathogenesis and diagnostic criteria of IRIS in individuals with human immunodeficiency virus infection are covered. Clinical and radiological presentations as well as possible pathogenic mechanisms of IRIS in patients treated with natalizumab and fingolimod are discussed. The authors also report the case of a woman with multiple sclerosis treated with fingolimod, who experienced a severe relapse when she stopped treatment. Diagnostic criteria and prognostic factors for IRIS and rebound are needed in patients with multiple sclerosis who discontinue the new disease modification therapy.

Disseminated Mycobacterium Avium Complex in an Adolescent with Perinatally-Acquired HIV Infection

Mycobacterium avium complex (MAC) is the most frequent nontuberculous mycobacteria implicated in opportunistic infections that define acquired immunodeficiency syndrome. With highly active antiretroviral therapy, disseminated MAC (dMAC) has become a rare entity. This unique case of dMAC was diagnosed in an adolescent with newly diagnosed perinatally-acquired HIV infection whose initial CD4 cell count was severely depleted and viral load was extremely high. While maximized treatment regimen had not been able to control his dMAC, improvement was noted when granulocyte macrophage colony-stimulating factor (GM-CSF) was added. GM-CSF should be considered as an adjunctive therapy in patients with refractory dMAC.

Incidence of disseminated Mycobacterium avium-complex infection in HIV patients receiving antiretroviral therapy with use of Mycobacterium avium-complex prophylaxis

The incidence of disseminated Mycobacterium avium complex (MAC) infection in HIV patients has fallen markedly since the introduction of effective antiretroviral therapy (ART). However, current guidelines still recommend primary prophylaxis. We conducted a retrospective cohort study in a university-affiliated hospital from January 1998 to January 2014. During that period, HIV patients who had at least one CD4 cell count below 50 cells/mm³ and had been treated with ART were enrolled. We compared incidence of disseminated MAC infection in the 12 months after the first CD4 cell count below 50 cells/mm³ between prophylaxis and nonprophylaxis groups. A total of 157 patients were enrolled and the total observation period was 144 patient-years (PY). Thirty-three patients (21%) received primary MAC prophylaxis. The initial CD4 cell count of the prophylaxis group was lower than that of the nonprophylaxis group ( P = 0.024), but the proportion of patients who reached a CD4 cell count >100 cells/mm³ ( P = 0.234) and were virologically suppressed ( P = 0.513) 12 months after ART commencement was not different in the prophylaxis and nonprophylaxis groups. The incidence of MAC did not differ significantly between the groups (3.4/100 PY versus 0.8/100 PY, P = 0.368). Routine MAC prophylaxis may be not required in the era of effective ART.

Immune Reconstitution Inflammatory Syndrome: Opening Pandora's Box

One of the purposes of antiretroviral therapy (ART) is to restore the immune system. However, it can sometimes lead to an aberrant inflammatory response and paradoxical clinical worsening known as the immune reconstitution inflammatory syndrome (IRIS). We describe a 23-year-old male, HIV1 infected with a rapid progression phenotype, who started ART with TCD4+ of 53 cells/mm³ (3,3%) and HIV RNA = 890000 copies/mL (6 log). Four weeks later he was admitted to the intensive care unit with severe sepsis. The diagnostic pathway identified progressive multifocal leukoencephalopathy, digestive Kaposi sarcoma, and P. aeruginosa bacteraemia. Five weeks after starting ART, TCD4+ cell count was 259 cells/mm³ (15%) and HIV RNA = 3500 copies/mL (4 log). He developed respiratory failure and progressed to septic shock and death. Those complications might justify the outcome but its autopsy opened Pandora's box: cerebral and cardiac toxoplasmosis was identified, as well as hemophagocytic syndrome, systemic candidiasis, and Mycobacterium avium complex infection. IRIS remains a concern and eventually a barrier to ART. Male gender, young age, low TCD4 cell count, and high viral load are risk factors. The high prevalence of subclinical opportunistic diseases highlights the need for new strategies to reduce IRIS incidence.

Prolonged tuberculosis-associated immune reconstitution inflammatory syndrome: characteristics and risk factors

Background

In a proportion of patients with HIV-associated tuberculosis who develop paradoxical immune reconstitution inflammatory syndrome (IRIS), the clinical course of IRIS is prolonged necessitating substantial health care utilization for diagnostic and therapeutic interventions. Prolonged TB-IRIS has not been prospectively studied to date. We aimed to determine the proportion of patients with prolonged TB-IRIS, as well as the clinical characteristics and risk factors for prolonged TB-IRIS.

Methods

We pooled data from two prospective observational studies and a randomized controlled trial conducted in Cape Town, South Africa, that enrolled patients with paradoxical TB-IRIS. We used the same diagnostic approach and clinical case definitions for TB-IRIS in the 3 studies. Prolonged TB-IRIS was defined as TB-IRIS symptoms lasting > 90 days. Risk factors for prolonged TB-IRIS were analysed using Wilcoxon rank sum test, Fisher’s exact test, multivariate logistic regression and Cox proportional hazards models.

Results

Two-hundred and sixteen patients with TB-IRIS were included. The median duration of TB-IRIS symptoms was 71.0 days (IQR 41.0–113.2). In 73/181 patients (40.3 %) with adequate follow-up data, IRIS duration was > 90 days. Six patients (3.3 %), mainly with lymph node involvement, had IRIS duration > 1 year. In univariate logistic regression analysis the following were significantly associated with IRIS duration > 90 days: lymph node involvement at initial TB diagnosis, drug-resistant TB, lymph node TB-IRIS, and not being hospitalised at time of TB-IRIS diagnosis. In our multivariate logistic regression model lymph node TB-IRIS (aOR 2.27, 95 % CI 1.13–4.59) and not being hospitalised at time of TB-IRIS diagnosis (aOR for being hospitalised 0.5, 95 % CI 0.25-0.99) remained significantly associated with prolonged TB-IRIS, and drug-resistant TB was of borderline significance (aOR 3.26, 95 % CI 0.97–12.99). The association of not being hospitalised with longer duration of IRIS might be related to 1 of the 3 cohorts in which all patients were hospitalised at ART initiation with close inpatient follow-up. This could have resulted in diagnosis of milder cases and earlier IRIS treatment potentially resulting in shorter TB-IRIS duration in these hospitalised patients.

Conclusions

Around 40 % of patients with TB-IRIS have symptoms for more than 90 days. Involvement of lymph nodes at time of TB-IRIS is an independent risk factor for prolonged TB-IRIS. Future studies should address whether more prompt anti-inflammatory treatment of lymph node TB-IRIS reduces the risk of prolonged TB-IRIS.

Trial registration

The randomized controlled trial was registered with Current Controlled Trials ISRCTN21322548 on 17 August 2005.

Electronic supplementary material

The online version of this article (doi:10.1186/s12879-016-1850-2) contains supplementary material, which is available to authorized users.

Mycobacteria

The immunocompromised host is at increased risk of Mycobacterium tuberculosis complex and nontuberculous mycobacteria infection. Although Mycobacterium tuberculosis complex is a significant mycobacterial pathogen, nontuberculous mycobacteria causes substantial disease in those with suppressed immune responses. Mycobacterial infections can cause significant morbidity and mortality in this patient population, and rapid identification and susceptibility testing of the mycobacterial species is paramount to patient management and outcomes. Mycobacterial diagnostics has undergone some significant advances in the last two decades with immunodiagnostics (interferon gamma release assay), microscopy (light-emitting diode), culture (automated broth-based systems), identification (direct PCR, sequencing and matrix-assisted laser-desorption ionization–time of flight mass spectrometry) and susceptibility testing (molecular detection of drug resistance from direct specimens or positive cultures). Employing the most rapid and sensitive methods in the mycobacterial laboratory will have a tremendous impact on patient care and, in the case of Mycobacterium tuberculosis complex, in the control of tuberculosis.

Vertebral osteomyelitis caused by non-tuberculous mycobacteria: Predisposing conditions and clinical characteristics of six cases and a review of 63 cases in the literature

Background Several case series have reported on clinical and radiographic characteristics of patients with vertebral osteomyelitis (VO) caused by non-tuberculous mycobacteria (NTM). However, only a few patients were included, and systematic reviews are still lacking. The aim of this study was to update and summarise the pre-disposing conditions, clinical and radiographic characteristics of such cases due to NTM. Methods In this study, a systematic review was conducted of the English-language literature from 1961-2014 to investigate the pre-disposing conditions and characteristics of cases of VO due to NTM. Also, six additional cases diagnosed in the study hospitals were described; these cases are included in an analysis of a total of 69 cases of NTM VO. Results The most common species, regardless of the presence of HIV co-infection, was M. avium Complex followed by M. xenopi. Ten cases with HIV infection had a median CD4 lymphocyte count of 320/mm(3) (range = 41-465/mm(3)) at the time of diagnosis of NTM VO. The VO in the cases with HIV infections occurred at an earlier age and more often involved the thoracic spine than in the cases without HIV infection. Pre-disposing trauma or surgery was reported in 14.5% (10/69) of the cases. A variety of immunosuppressive diseases were observed in 49.3% of the patients, including the 10 with HIV infections and corticosteroids were used in 27.5% of the cases. Surgery was performed in 67.6% and improvement was reported in 80.6%. Conclusion NTM should be considered in immunocompromised patients with indolent VO without confirmation of tuberculosis.

High Mortality of Disseminated Non-Tuberculous Mycobacterial Infection in HIV-Infected Patients in the Antiretroviral Therapy Era

Background

Little information is available on the mortality and risk factors associated with death in disseminated non-tuberculous mycobacterial infection (dNTM) in HIV-infected patients in the ART-era.

Methods

In a single-center study, HIV-infected dNTM with positive NTM culture from sterile sites between 2000 and 2013 were analysed. The clinical characteristics at commencement of anti-mycobacterial treatment (baseline) were compared between those who survived and died.

Results

Twenty-four patients were analyzed. [The median CD4 27/μL (range 2–185)]. Mycobacterium avium and M. intracellulare accounted for 20 (83%) and 3 (13%) of isolated NTM. NTM bacteremia was diagnosed in 15 (63%) patients. Seven (29%) patients died, and NTM bacteremia was significantly associated with mortality (p = 0.022). The baseline CD4 count was significantly lower in the non-survivors than the survivors (median 7/μL versus 49, p = 0.034). Concomitant AIDS-defining diseases or malignancies were not associated with mortality. Immune-reconstitution syndrome (IRS) occurred to 19 (79%) patients (8 paradoxical and 11 unmasking), and prognosis tended to be better in unmasking-IRS than the other patients (n = 13) (p = 0.078). Patients with paradoxical-IRS had marginally lower CD4 count and higher frequency of bacteremia than those with unmasking-IRS (p = 0.051, and 0.059). Treatment with systemic corticosteroids was applied in 63% and 55% of patients with paradoxical and unmasking-IRS, respectively.

Conclusion

dNTM in HIV-infected patients resulted in high mortality even in the ART-era. NTM bacteremia and low CD4 count were risk factors for death, whereas patients presented with unmasking-IRS had marginally better prognosis. IRS occurred in 79% of the patients, suggesting difficulty in the management of dNTM.

Paradoxical reactions and immune reconstitution inflammatory syndrome in tuberculosis

The coalescence of the HIV-1 and tuberculosis (TB) epidemics in Sub-Saharan Africa has had a significant and negative impact on global health. The availability of effective antimicrobial treatment for both HIV-1 (in the form of highly active antiretroviral therapy (HAART)) and TB (with antimycobacterial agents) has the potential to mitigate the associated morbidity and mortality. However, the use of both HAART and antimycobacterial therapy is associated with the development of inflammatory paradoxical syndromes after commencement of therapy. These include paradoxical reactions (PR) and immune reconstitution inflammatory syndromes (IRIS), conditions that complicate mycobacterial disease in HIV seronegative and seropositive individuals. Here, we discuss case definitions for PR and IRIS, and explore how advances in identifying the risk factors and immunopathogenesis of these conditions informs our understanding of their shared underlying pathogenesis. We propose that both PR and IRIS are characterized by the triggering of exaggerated inflammation in a setting of immunocompromise and antigen loading, via the reversal of immunosuppression by HAART and/or antimycobacterials. Further understanding of the molecular basis of this pathogenesis may pave the way for effective immunotherapies for the treatment of PR and IRIS.

Mycobacterium shigaense Causes Lymph Node and Cutaneous Lesions as Immune Reconstitution Syndrome in an AIDS Patient: The Third Case Report of a Novel Strain Non-tuberculous Mycobacterium

A 40-year-old man complaining of progressive body weight loss was diagnosed to have acquired immunodeficiency syndrome. Within 2 weeks after the initiation of combination antiretroviral therapy, he developed fever, massive cervical lymphadenopathy and a protruding subcutaneous abscess. A lymph node biopsy and abscess drainage revealed non-caseous granuloma and mycobacterium. The mycobacterium belonged to Runyon II group, but it showed no matches to any previously reported species. According to sequence analyses, the strain was identified as Mycobacterium shigaense. After six months of antimycobacterial treatment, the lesions were all successfully cured. This is the third case report of the novel mycobacterium, M. shigaense, presenting in associatioin with immune reconstitution syndrome.

Mycobacterium avium Complex Osteomyelitis in Persons With Human Immunodeficiency Virus: Case Series and Literature Review

In persons with advanced immunosuppression, Mycobacterium avium complex (MAC) typically causes disseminated disease with systemic symptoms. We report 2 cases in which MAC caused localized osteomyelitis in human immunodeficiency virus (HIV)-infected individuals on antiretroviral therapy with rising CD4 counts. We summarize 17 additional cases of HIV-associated MAC osteomyelitis from the literature and compare CD4 count at presentation for vertebral cases versus nonvertebral cases, which reveals a significantly higher CD4 at presentation for vertebral cases (median 251 cells/µL vs 50 cells/µL; P = .043; Mann-Whitney U test). The literature review demonstrates that the majority of cases of MAC osteomyelitis, especially vertebral, occurs in individuals with CD4 counts that have increased to above 100 cells/µL on antiretroviral therapy. Among HIV-infected individuals with osteomyelitis, MAC should be considered a possible etiology, particularly in the setting of immune reconstitution.

Immune reconstitution inflammatory syndrome due to Mycobacterium avium complex successfully followed up using 18 F-fluorodeoxyglucose positron emission tomography-computed tomography in a patient with human immunodeficiency virus infection: A case report

Background

In human immunodeficiency virus (HIV)-infected patients, immune reconstitution inflammatory syndrome (IRIS) due to nontuberculous mycobacteria (NTM) infection is one of the most difficult types of IRIS to manage. ¹⁸ F-fluorodeoxyglucose positron emission tomography/computed tomography (¹⁸ F-FDG PET/CT) has been suggested as a useful tool for evaluating the inflammatory status of HIV-infected patients. We present the first case of Mycobacterium avium complex (MAC)-associated IRIS (MAC-IRIS) that was successfully followed up using ¹⁸ F-FDG PET/CT.

Case presentation

A 44-year-old homosexual Japanese man was referred to our hospital with fever and dyspnea. He was diagnosed with Pneumocystis jiroveci pneumonia and found to be HIV positive. After the initiation of combined antiretroviral therapy (cART), the patient’s mediastinal and bilateral hilar lymphadenopathy gradually enlarged, and bilateral infiltrates appeared in the upper lung fields. ¹⁸ F-FDG PET/CT was performed five months after the initiation of cART and showed intense accumulation of fluorodeoxyglucose (FDG) corresponding to the lesions of infiltration as well as the mediastinal and bilateral hilar lymphadenopathy. A bronchial wash culture and pathology findings led to a diagnosis of MAC-IRIS. Anti-mycobacterial chemotherapy with rifampicin, ethambutol, clarithromycin, and levofloxacin was started. One year after the chemotherapy was initiated, there was a significant reduction in FDG uptake in the area of the lesions except in the mediastinal lymph node. This implied incomplete resolution of the MAC-IRIS-related inflammation. Anti-mycobacterial chemotherapy was continued because of the residual lesion. To date, the patient has not experienced a recurrence of MAC-IRIS, a period of nine months.

Conclusion

We present a case of MAC-IRIS in an HIV-infected patient whose disease activity was successfully followed up using ¹⁸ F-FDG PET/CT. Our data suggest that ¹⁸ F-FDG PET/CT is useful for evaluating the disease activity of NTM-IRIS and assessing the appropriate duration of anti-mycobacterial chemotherapy for NTM-IRIS in HIV-infected patients.

[Diagnosis of infectious lymphadenitis]

Adenitis is a common disorder requesting numerous medical specialties. Etiologies are dominated by viral and bacterial infections, and more rarely parasitic, or by neoplastic and inflammatory diseases. Nevertheless, etiology remains often unknown and invasive tests may be required. On nodal tissue sample, histological examination, culture and polymerase chain reaction (PCR) are realized. PCR has revolutionized the diagnostic approach and consequently, knowledge of infectious lymphadenopathy. Previously, staphylococcus, streptococcus and mycobacterium were the main infectious agents identified in lymph nodes. Since its use, new emergent microorganisms responsible of lymphadenitis have been identified. Bartonella henselae, responsible of cat scratch disease, is to date the infectious agent most often encountered in adenitis. Mycobacterium avium subsp. hominisuis has been recently described as responsible of children lymphadenitis. PCR has become an essential tool in the diagnostic process of infectious lymphadenitis. Here, we propose a literature review on infectious adenitis and we emphasize the diagnostic strategy of adenitis.

Mesenterial involvement of Mycobacterium genavense infection: hard to find, hard to treat

Mycobacterium genavense is a rare pathogen affecting severely immunosuppressed patients. We report the case of persistent relapsing M. genavense infection in a 48-year-old African man with a positive diagnosis of HIV infection. Despite being under effective antiretroviral therapy with partial immune reconstitution, he developed irreversible long-term abdominal complications, possibly due to persistent M. genavense infection and sustained inflammation. Case management consists of individual risk assessment, close follow-up and personalised treatment strategies concerning the duration of antimycobacterial therapy and early application of steroids. Patients with profound immunosuppression, a high viral load at HIV diagnosis and a high burden of M. genavense, appear to be at higher risk. The pathogenicity of this complication is not well known and its optimal management has still to be determined.

Disseminated Mycobacterium gordonae and Mycobacterium mantenii infection with elevated anti-IFN-γ neutralizing autoantibodies

A case of disseminated nontuberculous mycobacteria(l) (NTM) infection in a patient with positive neutralizing anti-interferon-γ (IFN-γ) autoantibodies involving bone, bronchus, systemic lymph nodes, and skin is reported. The causative NTMs were two different strains: Mycobacterium gordonae, which rarely causes true disease, and Mycobacterium mantenii, which is extremely rare. Anti-mycobacterial treatment successfully ameliorated all disseminated lesions. Although the concentration of anti-IFN-γ autoantibodies increased during the pre-treatment period, it gradually decreased after anti-mycobacterial treatment was started.

Mycobacterium haemophilum bone and joint infection in HIV/AIDS: case report and literature review

We report a case of disseminated Mycobacterium haemophilum osteomyelitis in a patient with advanced HIV infection, who later developed recurrent immune reconstitution inflammatory syndrome after commencement of antiretroviral therapy. We review previous reports of M. haemophilum bone and joint infection associated with HIV infection and describe the management of M. haemophilum-associated immune reconstitution inflammatory syndrome, including the role of surgery as an adjunctive treatment modality and the potential drug interactions between antiretroviral and antimycobacterial agents.

The immune pathogenesis of immune reconstitution inflammatory syndrome associated with highly active antiretroviral therapy in AIDS

The present study investigated the immunological pathogenesis of immune reconstitution inflammatory syndrome (IRIS) in acquired immunodeficiency syndrome (AIDS) patients undergoing highly active antiretroviral therapy (HAART). A total of 238 patients with AIDS who received initial HAART were included in this prospective cohort study. Blood samples were collected immediately, at baseline, at week 12, and at week 24 after initial HAART and at the onset of IRIS. Lymphocyte subsets, Th1 and Th2 cytokines, and interleukin (IL)-7 levels were measured by flow cytometry or ELISA. Among the 238 patients with AIDS who received HAART, 47 patients developed IRIS. The percentages of CD4(+) and CD8(+) naive, memory, and activated cells exhibited no significant differences between AIDS patients with and without IRIS 24 weeks after initial HAART. The percentage of CD4(+)CD25(+)Foxp3(+) regulatory T cells was lower in IRIS patients than in non-IRIS patients before HAART, 12 weeks after HAART, 24 weeks after HAART, and at the onset of IRIS. IL-2 and interferon (IFN)-γ levels were significantly higher at week 4 and at the onset of IRIS in IRIS patients than in non-IRIS patients. In contrast, IL-4 and IL-10 levels were significantly lower at week 4 and at the onset of IRIS in IRIS patients than in non-IRIS patients. Plasma IL-7 decreased gradually with the progression of HAART. The level of IL-7 was higher in IRIS patients than in non-IRIS patients at all follow-up time points. An imbalance of Th1/Th2 cytokines, a consistently low CD(+)CD25(+)Fox3(+) percentage, and a high IL-7 level may be crucial in the pathogenesis of IRIS in AIDS patients who had received HAART.

Clinical features and management of a severe paradoxical reaction associated with combined treatment of Buruli ulcer and HIV co-infection

Background

In West and Central Africa Buruli ulcer (BU) and HIV co-infection is increasingly recognised and management of these two diseases combined is an emerging challenge for which there is little published information. In this case we present a severe paradoxical reaction occurring after commencing antibiotic treatment for BU combined with antiretroviral therapy for HIV, and describe its clinical features and management. This includes to our knowledge the first reported use of prednisolone in Africa to manage a severe paradoxical reaction related to BU treatment.

Case presentation

A 30 year old immunosuppressed HIV positive man from Cameroon developed a severe paradoxical reaction 24 days after commencing antibiotic treatment for BU and 14 days after commencing antiretroviral therapy for HIV. Oral prednisolone was successfully used to settle the reaction and prevent further tissue loss. The antiretroviral regimen was continued unchanged and the BU antibiotic treatment not prolonged beyond the recommended duration of 8 weeks. A second small local paradoxical lesion developed 8 months after starting antibiotics and settled with conservative treatment only. Complete healing of lesions occurred and there was no disease recurrence 12 months after commencement of treatment.

Conclusions

Clinicians should be aware that severe paradoxical reactions can occur during the treatment of BU/HIV co-infected patients. Prednisolone was effectively and safely used to settle the reaction and minimize the secondary tissue damage.

Electronic supplementary material

The online version of this article (doi:10.1186/1471-2334-14-423) contains supplementary material, which is available to authorized users.