Immune reconstitution disease associated with mycobacterial infections in HIV-infected individuals receiving antiretrovirals

Non-tuberculous mycobacterial shoulder arthritis with acute exacerbation soon after initiation of immune checkpoint inhibitor: A case report

Immune checkpoint inhibitors (ICIs) have been approved for treating various cancers; however, they can cause immune-related adverse events. Generally, ICIs are not associated with an increased risk of infection, however, several reports demonstrated infections caused by non-tuberculous mycobacterium (NTM) during ICI therapy. Here, we report a case of NTM shoulder arthritis with acute exacerbation immediately after ICI initiation. A 75-year-old man was diagnosed with left shoulder arthritis caused by Mycobacterium intracellulare eight months before receiving ICI treatment and was treated with clarithromycin and ethambutol. However, the mild redness, swelling, heat, and shoulder pain persisted. The patient was diagnosed with hepatocellular carcinoma and atezolizumab and bevacizumab treatment was initiated; one day after the initiation of therapy, the patient presented with a fever and worsened shoulder symptoms. Considering the suspected worsening of NTM arthritis, sitafloxacin was additionally administered, and surgical debridement was performed. M. intracellulare was isolated through culturing shoulder synovial tissue; immunohistochemical staining analysis revealed programmed death-1 (PD-1) and programmed death ligand-1 (PD-L1) expression in granulation tissue cells. After the arthritis symptoms decreased, atezolizumab plus bevacizumab was resumed and continued with no recurrence of arthritis. The NTM exacerbation on the day after ICI administration suggests the potential involvement of the PD-1/PD-L1 pathway in the pathogenesis of NTM; moreover, adverse inflammatory reactions to NTM were possibly triggered through the blockade of this pathway.

Immune Reconstitution Inflammatory Syndrome-Induced Thrombocytopenia in a Patient With HIV and Coccidioidomycosis

Highly active antiretroviral therapy (HAART) is imperative in managing human immunodeficiency virus (HIV) infections. HAART aims to inhibit viral replication and improve immunity. Antiretroviral therapy has led to significant improvement in CD4-T cell counts and reductions in viral load, leading to improved overall immune function, increased survival, and decreased frequency of opportunistic infections. Immune reconstitution inflammatory syndrome (IRIS) is defined by a hyperinflammatory immune response within six months of initial treatment with HAART. It is caused by dysregulated inflammatory immune responses against pathogens. Herein, we discuss a rare presentation of IRIS-induced thrombocytopenia in a 20-year-old Hispanic male patient.

Liver Injury in People With HIV on Antituberculosis and/or Antiretroviral Therapy-Assessing Causality Using the Updated Roussel Uclaf Causality Assessment Method

PURPOSE

We compared performance of the Roussel Uclaf Causality Assessment Method (RUCAM) with multidisciplinary expert panel review in identifying a drug-induced liver injury (DILI) due to antituberculosis therapy (ATT) and/or antiretroviral therapy (ART).

METHODS

Cases were drawn from a prospective registry of hospitalised adults with suspected DILI due to ATT and/or ART in Cape Town, South Africa. Participants had to fulfil American Thoracic Society criteria for ATT interruption (alanine transaminase [ALT] ≥5 times upper limit of normal [ULN]/ALT ≥3 times [ULN] and symptomatic). Causality assessment by expert panel review served as reference standard. The panel ranked potentially implicated drugs as certain, probable, possible or unlikely causes guided by World Health Organization Uppsala Monitoring Centre criteria. The RUCAM was performed for each potentially implicated drug. We calculated sensitivity and specificity of the RUCAM in identifying a probable/certain drug cause for liver injury.

RESULTS

We included 48 participants. All were people with HIV (PWH). Twenty-seven were on concomitant ART and ATT, with a median of six potentially hepatotoxic drugs per case. Sensitivity and specificity of the RUCAM in identifying a probable/certain drug cause of liver injury compared with expert panel review was 7% and 100% respectively. Implicated drugs (times ranked probable/certain by panel) were isoniazid (18/0), pyrazinamide (17/0), rifampicin (15/1), efavirenz (6/4) and lopinavir/ritonavir (1/0).

CONCLUSIONS

PWH with liver injury received multiple potentially implicated drugs, which may increase liver injury risk and complicate causality assessment. Compared with expert panel review, the RUCAM had low sensitivity in detecting probable or certain drug causes of liver injury.

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.

Incidence and Predicting Factors of Opportunistic Infections after Antiretroviral Therapy Initiation among Treatment-naïve Patients with HIV Infection: A Retrospective Cohort Study in A Tertiary Care Hospital

OBJECTIVES

To determine the incidence of opportunistic infections (OIs) and the predictive factors for the development of OIs after antiretroviral therapy (ART) initiation among treatment-naïve patients with HIV infection.

RESULTS

Of 401 HIV-infected patients, 38 (9.5%) HIV-infected patients developed OIs after initiating ART, with an incidence rate of 25.6/1000 person-years. The median time (IQR) from ART initiation to OI occurrence was 26.5 (14-73) days. In multivariate Cox proportional hazard regression, body mass index ≤18.5 kg/m2 (adjusted hazard ratio [aHR] 2.28, 95% confidence interval [CI] 1.18-4.42, P = .015), symptoms at presentation (aHR 13.59, 95% CI 3.24-56.9, P < .001), serum glutamate-pyruvate transaminase >55 U/L (aHR 2.09, 95% CI 1.06-4.15, P = .035), and initiation of a dolutegravir-based regimen (aHR 4.39, 95% CI 1.54-12.48, P = .006) were significantly associated with OIs after ART initiation.

CONCLUSION

OIs after ART initiation are common. Malnutrition, symptomatic presentation, abnormal liver enzymes, and DTG-based regimens are predictors of OI occurrence after ART initiation. Physicians must monitor and appropriately treat OIs after ART initiation.

Nutritional Status in Leprosy Patients: A Systematic Review and Meta-analysis

BACKGROUND

Leprosy, a chronic mycobacterial disease, is frequently accompanied by malnutrition. However, it is important to regularly assess the nutritional state of leprosy patients in a resource-poor nation like India, where undernutrition is widespread.

OBJECTIVES

This study aimed to compare the nutritional status of leprosy patients to that of normal individuals using the body mass index.

METHODS

The electronic databases PubMed, Google Scholar, and Embase were used to conduct an open literature search. From 1st January 2000 to 31st January 2023, all articles were screened using the following MeSH terms: (nutrition OR body mass index OR body weight) AND (leprosy OR lepra) to find possibly relevant articles.

RESULTS

This meta-analysis includes five research studies with a total of 1173 individuals (363 patients in the leprosy group and 810 patients in the non-leprosy group). The weighted mean difference (WMD) for BMI studies was -17.88 (95% CI -27.65 to -8.12), showing that there was a significant difference in BMI < 18.5 between leprosy patients and non-leprosy patients. There was a significant difference in DDS score and HFIAS score between patients with leprosy and non-leprosy. In a total of 342 leprosy patients, 206 developed deformities.

CONCLUSION

This research increases our understanding of nutrition and leprosy. The results found that people with leprosy are nutritionally at a distinct disadvantage when compared to non-leprosy patients. It emphasises the several ways in which diet may generate circumstances that increase the risk of leprosy.

Converging Epidemics: A Narrative Review of Tuberculosis (TB) and Human Immunodeficiency Virus (HIV) Coinfection

Tuberculosis (TB), primarily caused by Mycobacterium tuberculosis (MTB), remains a leading cause of mortality in individuals living with human immunodeficiency virus (HIV) infection, posing a significant strain on healthcare systems. Coinfection of HIV and TB results in a mutually advantageous relationship that accelerates the progression of both diseases. TB is a major contributor to mortality in individuals with HIV. However, diagnosing coinfected individuals is challenging due to the prevalence of extrapulmonary TB and smear-negative disease. Over the past decade, significant progress has been made in the fight against TB, thanks to advances in molecular techniques. Yet, these molecular diagnostic assays remain inaccessible to many individuals coinfected with HIV and TB due to their high cost. To expedite treatment and reduce transmission, it is crucial to integrate HIV and TB control programs more closely, thereby minimizing diagnostic delays and enhancing early case detection. This review aims to provide a comprehensive overview of the current state of knowledge regarding the interplay between HIV and TB. It highlights recent developments in sensitive and rapid TB diagnostic tests, cutting-edge preventive strategies, and the screening of individuals coinfected with both HIV and TB. The objectives of this review are to shed light on the complex relationship between these two diseases and to emphasize the importance of integrated efforts in combating their impact on public health.

HIV and Associated TB: A Lethal Association for Kidney Health?

Human immunodeficiency virus (HIV) and tuberculosis (TB) are the leading infectious causes of death globally. The combined brunt of these diseases is experienced mainly in low-income and lower-middle-income countries. HIV/TB have devastating effects on the kidneys, leading to accelerated decline of kidney function as well as mortality. Managing the triad of TB/HIV and kidney disease is challenging. We discuss the epidemiology of HIV/TB coinfection and the kidney and the key mechanisms of kidney disease including genetic susceptibility. The clinical presentation and pathology, as well as the challenges of diagnosing CKD in these patients, also are discussed. The strategies to prevent and manage HIV/TB-related kidney disease such as proper assessment, avoiding nephrotoxic regimens, drug dose adjustments, kidney function monitoring, avoidance of drug-drug interactions, and other interventions are explored. We also briefly discuss the complexities around HIV/TB patients on dialysis and kidney transplantation. HIV/TB coinfection presents an increased risk for kidney-related morbidity and mortality; patients with this triad need to be given special consideration for future research and management.

HIV-Associated Immune Dysregulation in the Skin: A Crucible for Exaggerated Inflammation and Hypersensitivity

Skin diseases are hallmarks of progressive HIV-related immunosuppression, with severe noninfectious inflammatory and hypersensitivity conditions as common as opportunistic infections. Conditions such as papular pruritic eruption are AIDS defining, whereas delayed immune-mediated adverse reactions, mostly cutaneous, occur up to 100-fold more during HIV infection. The skin, constantly in contact with the external environment, has a complex immunity. A dense, tightly junctioned barrier with basal keratinocytes and epidermal Langerhans cells with antimicrobial, innate-activating, and antigen-presenting functions form the frontline. Resident dermal dendritic, mast, macrophage, and innate lymphoid cells play pivotal roles in directing and polarizing appropriate adaptive immune responses and directing effector immune cell trafficking. Sustained viral replication leads to progressive declines in CD4 T cells, whereas Langerhans and dermal dendritic cells serve as viral reservoirs and points of first viral contact in the mucosa. Cutaneous cytokine responses and diminished lymphoid populations create a crucible for exaggerated inflammation and hypersensitivity. However, beyond histopathological description, these manifestations are poorly characterized. This review details normal skin immunology, changes associated with progressive HIV-related immunosuppression, and the characteristic conditions of immune dysregulation increased with HIV. We highlight the main research gaps and several novel tissue-directed strategies to define mechanisms that will provide targeted approaches to prevention or treatment.

A Rare Case of Cytomegalovirus Colitis with Subsequent Non-tubercular Mycobacteria Immune Reconstitution Inflammatory Syndrome

Cytomegalovirus (CMV) colitis occurs commonly in immunocompromised patients with high mortality. CMV infection has also been reported in immunocompetent individuals and it has a varied clinical presentation. When HIV-infected patients are started on antiretroviral therapy (ART) there is a reconstitution of the immune system which results in the paradoxical worsening of existing conditions or development of new disease conditions known as immune reconstitution inflammatory syndrome (IRIS). In the setting of IRIS one of the most common infections to occur is non-tubercular mycobacteria (NTM). The infection generally develops when the CD4 count is < 50 cells/µL. Here we present a rare case of CMV colitis followed by NTM infection in the setting of IRIS, its management, and treatment outcomes.

Leprosy as immune reconstitution inflammatory syndrome in patients living with HIV: Description of French Guiana’s cases over 20 years and systematic review of the literature

Background

HIV infection is highly prevalent in French Guiana, a territory where leprosy is also endemic. Since the introduction of Highly Active Antiretroviral Treatment (HAART) in the management of HIV, leprosy has been reported as part of the immune reconstitution inflammatory syndrome (IRIS).

Methodology/Principal findings

We aimed to present a general description of these forms of leprosy as IRIS, highlighting clinical and therapeutic specificities. A retrospective study was conducted in French Guiana, including patients living with HIV (PLHIV) with advanced infection (CD4 < 200/mm3) and developing leprosy or a leprosy reaction within six months of HAART initiation, from 2000 to 2020. Clinical, histological and biological data were collected for all these patients. Six patients were reported in French Guiana. A systematic review of the literature was conducted, and its results were added to an overall analysis. Overall, seventy-three PLHIV were included. They were mainly men (74%), aged 22–54 years (median 36 years), mainly from Brazil (46.5%) and India (32.8%). Most leprosy cases (56.2%) were borderline tuberculoid (BT). Leprosy reactions were frequent (74%), mainly type 1 reaction (T1R) (68.5%), sometimes intense with ulceration of skin lesions (22%). Neuritis was observed in 30.1% of patients. The outcome was always favorable under multidrug therapy (MDT), continuation of HAART and additional corticosteroid therapy in case of neuritis or ulceration. There was no relapse.

Conclusion

Leprosy as IRIS in PLHIV mainly presents as a BT leprosy in a T1R state, sometimes with ulcerated skin lesions. Response to MDT is usually good. Systemic corticosteroids are necessary and efficient in case of neuritis.

Leprosy is an infection caused by Mycobacterium leprae characterized by skin and nerve lesions. Leprosy reactions can be observed, depending on variations in host-specific cellular immunity. Leprosy is described after antiretroviral therapy (HAART) initiation in immunocompromised PLHIV from countries where leprosy and HIV infections are endemic. This is known as immune restoration inflammatory syndrome (IRIS), a brutal inflammatory response directed against a latent or quiescent pathogen. In this study we searched for cases of leprosy as IRIS in French Guiana and those published in the literature in order to describe their clinical characteristics. Overall, our results show that these cases are mostly observed as borderline tuberculoid leprosy, associated with or quickly followed by a type 1 leprosy reaction, sometimes with neuritis and/or ulceration of lesions. The outcome is favorable under standard leprosy treatment with HAART maintenance.

The safety and efficacy of immunotherapy with anti-programmed cell death 1 monoclonal antibody for lung cancer complicated with Mycobacterium tuberculosis infection

Background

Anti-programmed cell death 1 (PD-1)/programmed cell death-ligand 1 (PD-L1) immunotherapy has boosted the prognosis in advanced lung cancer. Meanwhile, accumulating cases showed the correlation between tuberculosis (TB) reactivation and anti-PD-1/PD-L1 immunotherapy. However, the safety and efficacy of anti-PD-1/PD-L1 immunotherapy for lung cancer complicated with TB infection could only be learned from real-world data.

Methods

We retrospectively analyzed 562 patients with advanced lung cancer who received anti-PD-1/PD-L1 immunotherapy at Shanghai Pulmonary Hospital from 2015 to 2019, including 13 patients with TB infection. Besides, relevant literature reviews were performed online to analyze the safety and efficacy of immunotherapy and to explore the appropriate treatment strategies in this specific population.

Results

In our cohort, the initiation of anti-PD-1/PD-L1 immunotherapy was from June 2015 to December 2019. Among them, 13 patients had TB infection prior to immunotherapy including 11 latent TB and 2 active TB, and all of them were treated with anti-PD-1 immunotherapy. Patients with active TB infection were treated with concurrent anti-TB and anti-PD-1 treatments, and the remaining received either mono-immunotherapy or combined immunotherapy. Neither reactivation of latent TB nor progression of active TB was monitored in our cohort during immunotherapy. Severe immune-related adverse events (irAEs) were diagnosed in two patients. Treatment strategies such as discontinuation of immunotherapy and administration of corticosteroids were provided timely, and one with latent TB infection got gradually improved, but the other one with active TB died quickly. The median progression-free survival (PFS) was 5.5 months for tumor immunotherapy in our cohort. However, the PFS of immunotherapy was merely 2.1 and 2.2 months in lung cancer patients with active TB infection.

Conclusions

Immunotherapy is relatively safe for lung cancer patients complicated with previously treated latent TB, and the efficacy of immunotherapy in this specified population is not inferior to that in lung cancer patients without TB infection. TB screening before anti-PD-1/PD-L1 immunotherapy is strongly recommended, and irAEs should be monitored more cautiously in lung cancer patients with active TB infection.

Varying clinical presentations of nontuberculous mycobacterial disease : Similar to but different from tuberculosis

The incidence rate of pulmonary nontuberculous mycobacterial disease (PNTMD) in Japan is the highest among major industrialized nations. Although the typical clinical course and radiological manifestations of PNTMD are different from those of pulmonary tuberculosis (TB), confusion about these mycobacterial diseases leads to a diagnostic pitfall. Diagnostic challenges include the coexistence of Mycobacterium tuberculosis (MTB) and nontuberculous mycobacteria (NTM), false positives for NTM in MTB nucleic acid amplification tests, microbial substitution, and abnormal radiological manifestations caused by NTM. Features of extrapulmonary NTM diseases, such as pleurisy, vertebral osteomyelitis, and disseminated disease, are different from the corresponding tuberculous diseases. Moreover, the immunological background of the patient (status of human immunodeficiency virus infection with or without antiviral therapy, continuation or discontinuation of immunosuppressive therapy, use of immune checkpoint inhibitor, pregnancy and delivery, etc.) influences the pathophysiology of mycobacterial diseases. This review describes the varying clinical presentations of NTM disease with emphasis on the differences from TB. J. Med. Invest. 68 : 220-227, August, 2021.

Acute tubulointerstitial nephritis in a patient with early bronchial tuberculosis

Patients with chronic kidney disease (CKD) are commonly at high risk of tuberculosis (TB). Conversely, TB rarely causes tubulointerstitial nephritis. A 75-year-old Japanese man who was undergoing periodic follow-ups for CKD stage G3aA3 with membranous nephropathy was diagnosed with acute kidney injury (AKI) (estimated glomerular filtration rate [eGFR]: 15 mL/min/1.73 m²) without prerenal AKI. He reported developing recent-onset cough 3 weeks prior to presenting to us. Renal biopsy revealed acute tubulointerstitial nephritis along with known membranous nephropathy. CD4⁺ helper T cells comprised most lymphocytes in the tubulointerstitium. Results of the interferon-gamma release assay, sputum smear test, polymerase chain reaction (PCR), and culture test were positive for TB. Chest computed tomography revealed thickening of the left bronchial wall; therefore, a diagnosis of early bronchial TB was made; his urine culture and PCR were negative for TB. At four months after TB treatment with no immunosuppressive therapy, his eGFR improved to 50 mL/min/1.73 m², and based on this progress, the AKI was diagnosed as tuberculosis-associated tubulointerstitial nephritis (TATIN). Although TATIN typically occurs with chronic or miliary tuberculosis, it is very rare in early bronchial TB. Identification of TATIN is important in kidney diseases of unknown etiology, and treatment with anti-TB drugs is necessary.

Anti-interferon-gamma autoantibody related disseminated nontuberculous mycobacteriosis with pathological features of immunoglobulin G4-related disease

A 72-year-old man who was diagnosed as pulmonary mycobacterium avium complex (MAC) disease had suffered from antibiotics resistant fever with left renal enlargement surrounded by inflammatory change and multiple osteolytic lesions on computed tomography (CT). The renal biopsied samples pathologically showed immunoglobulin G4 (IgG4) positive plasma cell infiltration and many acid-fast bacilli without granuloma formation. Nucleic acid identification test for MAC from the samples of vertebral osteolytic lesion was positive. In the autopsy samples from left kidney, epithelioid cell granuloma and Langhans giant cell with many acid-fast bacilli were shown pathologically. In addition to osteolytic lesions on CT study, these pathological findings were not consistent with IgG4-related disease (IgG4-RD). The diagnosis of disseminated nontuberculous mycobacteriosis was made, and plasma anti-interferon-gamma (IFN-γ) autoantibody was found as the cause of underlying immunodeficiency. Disturbed function of IFN-γ resulted in impaired ability of phagocytic cells against pathogens and leading to spread of infection. T-helper type 2 dominant immune response was induced by prolonged antigenic stimulation of mycobacteria, which might have contributed to form the pathological features of IgG4-RD.

Mycobacterium abscessus Gastric Band Infection Complicated by Immune Reconstitution Inflammatory Syndrome and Cured in the Context of Allogeneic Hematopoietic Stem Cell Transplantation

We present a case of abdominal gastric band-associated Mycobacterium abscessus infection, manifesting after the onset of acute myeloid leukemia, complicated by immune reconstitution inflammatory syndrome (IRIS), and cured while receiving an allogeneic hematopoietic stem cell transplant. IRIS should be considered in less classical situations where there is unexplained clinical deterioration.

Antiretroviral therapy does not reduce tuberculosis reactivation in a tuberculosis-HIV coinfection model

While the advent of combination antiretroviral therapy (ART) has significantly improved survival, tuberculosis (TB) remains the leading cause of death in the HIV-infected population. We used Mycobacterium tuberculosis/simian immunodeficiency virus-coinfected (M. tuberculosis/SIV-coinfected) macaques to model M. tuberculosis/HIV coinfection and study the impact of ART on TB reactivation due to HIV infection. Although ART significantly reduced viral loads and increased CD4+ T cell counts in blood and bronchoalveolar lavage (BAL) samples, it did not reduce the relative risk of SIV-induced TB reactivation in ART-treated macaques in the early phase of treatment. CD4+ T cells were poorly restored specifically in the lung interstitium, despite their significant restoration in the alveolar compartment of the lung as well as in the periphery. IDO1 induction in myeloid cells in the inducible bronchus-associated lymphoid tissue (iBALT) likely contributed to dysregulated T cell homing and impaired lung immunity. Thus, although ART was indispensable for controlling viral replication, restoring CD4+ T cells, and preventing opportunistic infection, it appeared inadequate in reversing the clinical signs of TB reactivation during the relatively short duration of ART administered in this study. This finding warrants the modeling of concurrent treatment of TB and HIV to potentially reduce the risk of reactivation of TB due to HIV to inform treatment strategies in patients with M. tuberculosis/HIV coinfection.

An Inflammatory Composite Score Predicts Mycobacterial Immune Reconstitution Inflammatory Syndrome in People with Advanced HIV: A Prospective International Cohort Study

BACKGROUND

Immune reconstitution inflammatory syndrome (IRIS) is a common cause of morbidity among people with human immunodeficiency virus (PWH) who initiate antiretroviral therapy (ART) with severe lymphopenia. Easily accessible tools that reliably predict emergence and elucidate pathogenesis of IRIS are needed to facilitate improved clinical management.

METHODS

Plasma levels of biomarkers were measured before ART initiation in a large multinational cohort of ART-naive PWH with severe immunosuppression (CD4+ count <100 cells/mm3) in United States, Kenya, and Thailand. We performed a series of multiparametric analyses of inflammatory and clinical biomarkers and developed a composite score merging relevant biomarkers for use in a prediction model.

RESULTS

We identified a distinct baseline inflammatory profile and changes in inflammatory networks among biomarkers in participants who subsequently developed mycobacterial or viral IRIS. We also developed a composite score incorporating biomarkers associated with IRIS (interleukin-6 [IL-6], IL-10, IL-27, sCD14, interferon-γ, tumor necrosis factor-α, hyaluronic acid, D-dimer, body mass index, and hemoglobin) that accurately predicted mycobacterial IRIS and death in this cohort.

CONCLUSIONS

Systemic inflammatory profiles in PWH with severe immunosuppression are predictive of IRIS. Composite scores for the prediction of mycobacterial IRIS and death could be useful for risk stratification in PWH and lymphopenia initiating ART.

CLINICAL TRIALS REGISTRATION

NCT00286767.

Characteristics of paradoxical tuberculosis-associated immune reconstitution inflammatory syndrome and its influence on tuberculosis treatment outcomes in persons living with HIV

OBJECTIVE

The influence of tuberculosis (TB)-immune reconstitution inflammatory syndrome (IRIS) on TB treatment outcomes and its risk factors were investigated among people with human immunodeficiency virus (HIV) and co-infected with TB.

METHODS

Newly diagnosed, culture-confirmed, pulmonary TB patients with HIV and enrolled in a clinical trial (NCT00933790) were retrospectively analysed for IRIS occurrence. Risk factors and TB outcomes (up to 18 months after initiation of anti-TB treatment [ATT]) were compared between people who experienced IRIS (IRIS group) and those who did not (non-IRIS group).

RESULTS

TB-IRIS occurred in 82 of 292 (28%) participants. Significant baseline risk factors predisposing to TB-IRIS occurrence in univariate analysis were: lower CD4⁺ T-cell count, CD4/CD8 ratio, haemoglobin levels, presence of extra-pulmonary TB focus, and higher HIV viral load; the last two retained significance in the multivariate analysis. After 2 months of ATT commencement, sputum smear conversion was documented in 45 of 80 (56.2%) vs. 124 of 194 (63.9%) (p=0.23), culture conversion was in 75 of 80 (93.7%) vs. 178 of 194 (91.7%) (p=0.57) and the median decline in viral load (log₁₀copies/mm³) was 2.7 in the IRIS vs. 1.1 in the non-IRIS groups (p<0.0001), respectively. An unfavourable response to TB therapy was detected in 17 of 82 (20.7%) and 28 of 210 (13.3%) in the IRIS and non-IRIS groups, respectively (p=0.14).

CONCLUSIONS

TB-IRIS frequently occurred in people with advanced HIV infection and in those who presented with extra-pulmonary TB lesions, without influencing subsequent TB treatment outcomes.

BCG-Related Inflammatory Syndromes in Severe Combined Immunodeficiency After TCRαβ+/CD19+ Depleted HSCT

INTRODUCTION

The live-attenuated BCG vaccine is known to cause disseminated Mycobacterium bovis infection in patients with severe combined immunodeficiency (SCID). However, BCG-related post-hematopoietic stem cell transplantation (HSCT) immune reconstitution inflammatory syndromes, similar to those described in patients with HIV infections, are less-known complications of SCID.

PATIENTS AND METHODS

We reported on 22 BCG-vaccinated SCID patients who had received conditioned allogeneic HSCT with TCRαβ+/CD19+ graft depletion. All BCG-vaccinated patients received anti-mycobacterial therapy pre- and post-HSCT. Post-transplant immunosuppression consisted of tacrolimus in 10 patients and of 8 mg/kg tocilizumab (d-1, + 14, + 28) and 10 mg/kg abatacept (d-1, + 5, + 14, + 28) in 11 patients.

RESULTS

Twelve patients, five of whom had BCG infection prior to HSCT, developed BCG-related inflammatory syndromes (BCG-IS). Five developed early BCG-IS with the median time of manifestation 11 days after HSCT, corresponding with a dramatic increase of CD3+TCRγδ+ in at least two patients. Early BCG-IS was noted in only one out of 11 patients who received tocilizumab/abatacept and 4 out of 11 patients who did not. Seven patients developed late BCG-IS which corresponded to T cell immune recovery; at the time of manifestation (median 4.2 months after HSCT), the median number of CD3+ cells was 0.42 × 10⁹/ and CD3+CD4+ cells 0.27 × 10⁹/l. In all patients, late BCG-IS was controlled with IL-1 or IL-6 inhibitors.

CONCLUSION

BCG-vaccinated SCID patients undergoing allogeneic HSCT with TCRαβ+/CD19+ graft depletion are at an increased risk of early and late BCG-IS. Anti-inflammatory therapy with IL-1 and IL-6 blockade is efficient in the prevention of early and treatment of late BCG-IS.

Determinants of loss to follow-up among HIV positive patients receiving antiretroviral therapy in a test and treat setting: A retrospective cohort study in Masaka, Uganda

Background

Retaining patients starting antiretroviral therapy (ART) and ensuring good adherence remain cornerstone of long-term viral suppression. In this era of test and treat (T&T) policy, ensuring that patients starting ART remain connected to HIV clinics is key to achieve the UNAIDS 90-90-90 targets. Currently, limited studies have evaluated the effect of early ART initiation on loss to follow up in a routine health care delivery setting. We studied the cumulative incidence, incidence rate of loss to follow up (LTFU), and factors associated with LTFU in a primary healthcare clinic that has practiced T&T since 2012.

Methods

We retrospectively analyzed extracted routine program data on patients who started ART from January 2012 to 4^th July 2016. We defined LTFU as failure of a patient to return to the HIV clinic for at least 90 days from the date of their last appointment. We calculated cumulative incidence, incidence rate and fitted a multivariable Cox proportion hazards regression model to determine factors associated with LTFU.

Results

Of the 7,553 patients included in our sample, 3,231 (42.8%) started ART within seven days following HIV diagnosis. There were 1,180 cases of LTFU observed over 15,807.7 person years at risk. The overall incidence rate (IR) of LTFU was 7.5 (95% CI, 7.1–7.9) per 100 person years of observation (pyo). Cumulative incidence of LTFU increased with duration of follow up from 8.9% (95% CI, 8.2–9.6%) at 6 months to 20.2% (95% CI, 19.0–21.4%) at 48 months. Predictors of elevated risk of LTFU were: starting ART within 7 days following HIV diagnosis ((aHR) = 1.69, 95% CI, 1.50–1.91), lack of a telephone set (aHR = 1.52, 95% CI, 1.35–1.71), CD4 cell count of 200–350μ/ml (aHR = 1.21, 95% CI, 1.01–1.45) and baseline WHO clinical stage 3 or 4 (aHR = 1.35, 95% CI, 1.10–1.65). Factors associated with a reduced risk of LTFU were: baseline age ≥25 years (aHR ranging from 0.62, 95% CI, 0.47–0.81 for age group 25–29 years to 0.24, 95% CI, 0.13–0.44 for age group ≥50 years), at least primary education level (aHR ranging from aHR = 0.77, 95% CI, 0.62–0.94 for primary education level to 0.50, 95% CI, 0.34–0.75 for post-secondary education level), and having a BMI ≥ 30 (aHR = 0.28, 95% CI, 0.15–0.51).

Conclusion

The risk of loss to follow up increased with time and was higher among patients who started ART within seven days following HIV diagnosis, higher among patients without a telephone set, lower among patients aged ≥ 25 years, lower among patients with at least primary education and lower among patients with BMI of ≥ 30. In this era of T&T, it will be important for HIV programs to initiate and continue enhanced therapeutic education programs that target high risk groups, as well as leveraging on mHealth to improve patients’ retention on ART throughout the cascade of care.

Non-traumatic perforation of the jejunum in a human immunodeficiency virus-infected patient receiving combination antiretroviral therapy: A case report

RATIONALE

Non-traumatic bowel perforation caused by cytomegalovirus (CMV) and Mycobacterium avium complex (MAC) infections has become rare among patients with acquired immunodeficiency syndrome (AIDS) in the era of combination antiretroviral therapy (cART); however, CMV-associated and MAC-related immune reconstitution inflammatory syndrome (IRIS) has subsequently emerged owing to the wide use of integrase inhibitor-based regimens. Here we report a case of spontaneous perforation of the jejunum in a patient with human immunodeficiency virus (HIV) infection with good compliance to cART.

PATIENT CONCERNS

A 32-year-old HIV-infected man developed CMV disease and DMAC infection, as unmasking IRIS, 3 days after the initiation of cART. After appropriate treatment for opportunistic infections, intermittent fever with enlarged lymph nodes in the abdomen occurred as paradoxical IRIS. The patient was administered prednisolone with subsequent tapering according to his clinical condition.

DIAGNOSES

Unexpected perforation of hollow organ during the titration of steroid dose with clinical presentations of severe abdominal pain was diagnosed by chest radiography.

INTERVENTIONS

He underwent surgical repair with peritoneal toileting smoothly.

OUTCOMES

He was discharged well with a clean surgical wound on post-operative day 10.

LESSONS

Bowel perforation may be a life-threatening manifestation of IRIS in the era of cART. Steroids should be avoided, if possible, to decrease the risk of bowel perforation, especially in IRIS occurred after opportunistic diseases involving the gastrointestinal tract.

Atypical Mycobacterial Septic Arthritis of the Wrist: A Report of Two Cases

CASES

Two patients with human immunodeficiency virus (HIV) developed wrist pain following the initiation of antiretroviral treatment, and were diagnosed with chronic atypical mycobacterial septic arthritis. Aggressive operative debridement led to clinical improvement, provided tissue samples for diagnosis, and allowed for a targeted long-term antibacterial regimen.

CONCLUSION

Clinicians should consider atypical mycobacterial organisms as a cause of joint infection in patients with HIV. Symptoms may become apparent after patients experience immune system recovery following antiretroviral treatment.

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.

Population Structure and Implications on the Genetic Architecture of HIV-1 Phenotypes Within Southern Africa

The interesting history of Southern Africa has put the region in the spotlight for population medical genetics. Major events including the Bantu expansion and European colonialism have imprinted unique genetic signatures within autochthonous populations of Southern Africa, this resulting in differential allele frequencies across the region. This genetic structure has potential implications on susceptibility and resistance to infectious diseases such as human immunodeficiency virus (HIV) infection. Southern Africa is the region affected worst by HIV. Here, we discuss advances made in genome-wide association studies (GWAS) of HIV-1 in the past 12 years and dissect population diversity within Southern Africa. Our findings accentuate that a plethora of factors such as migration, language and culture, admixture, and natural selection have profiled the genetics of the people of Southern Africa. Genetic structure has been observed among the Khoe-San, among Bantu speakers, and between the Khoe-San, Coloureds, and Bantu speakers. Moreover, Southern African populations have complex admixture scenarios. Few GWAS of HIV-1 have been conducted in Southern Africa, with only one of these identifying two novel variants (HCG22rs2535307 and CCNG1kgp22385164) significantly associated with HIV-1 acquisition and progression. High genetic diversity, multi-wave genetic mixture and low linkage disequilibrium of Southern African populations constitute a challenge in identifying genetic variants with modest risk or protective effect against HIV-1. We therefore posit that it is compelling to assess genome-wide contribution of ancestry to HIV-1 infection. We further suggest robust methods that can pin-point population-specific variants that may contribute to the control of HIV-1 in Southern Africa.

Diet and nutrition: An important risk factor in leprosy

Leprosy, once considered as poor man's disease may cause severe neurological complications and physical disabilities. Classification of leprosy depends upon the cell mediated and humoral immune responses of the host, from tuberculoid to lepromatous stage. Current therapy to prevent the disease is not only very lengthy but also consists of expensive multiple antibiotics in combination. Treatment and the duration depend on the bacillary loads, from six months in paucibacillary to a year in multibacillary leprosy. Although as per WHO recommendations, these antibiotics are freely available but still out of reach to patients of many rural areas of the world. In this review, we have focused on the nutritional aspect during the multi-drug therapy of leprosy along with the role of nutrition, particularly malnutrition, on susceptibility of Mycobacterium leprae and development of clinical symptoms. We further discussed the diet plan for the patients and how diet plans can affect the immune responses during the disease.

Tuberculosis of the Central Nervous System

PURPOSE OF REVIEW

This article details the epidemiology and clinical manifestations of central nervous system (CNS) tuberculosis (TB), provides guidance for diagnostic imaging and CSF testing, and recommends treatment strategies for tuberculous meningitis and other forms of CNS TB, illustrating key aspects of diagnosis and management with case presentations.

RECENT FINDINGS

Although improvements in our understanding of the pathogenesis and management of CNS TB have occurred over the past 50 years, the emergence of multidrug-resistant and extensively drug-resistant TB, the advent of acquired immunodeficiency syndrome (AIDS), and the subsequent availability of highly active antiretroviral therapy that can produce the immune reconstitution inflammatory syndrome have complicated the diagnosis and treatment of CNS TB. Advances in diagnostic assays promise to increase the speed of diagnosis as well as the percentage of people with a confirmed rather than a presumptive diagnosis. Advances in precision medicine have identified polymorphisms in the LTA4H gene that influence the risk for inflammation in patients with tuberculous meningitis.

SUMMARY

CNS TB continues to be a major cause of morbidity and mortality, with the majority of people affected living in low-income and middle-income countries. Newer diagnostic assays promise to increase the speed of diagnosis and improve appropriate selection of antituberculous therapy and anti-inflammatory medications. Despite these advances, CNS TB remains difficult to diagnose, and clinicians should have a low threshold for initiating empiric therapy in patients with presumptive infection.

Splenic infarction complicated with immune reconstitution inflammatory syndrome due to disseminated Mycobacterium genavense infection in a patient infected with human immunodeficiency virus

Mycobacterium genavense (M. genavense) is one of the most fastidious, difficult to culture Mycobacterium species. Patients infected with human immunodeficiency virus (HIV) may develop immune reconstitution inflammatory syndrome (IRIS) due to disseminated M. genavense infection as well as disseminated M. avium and intracellulare complex infection. Consensus regarding treatment of IRIS due to disseminated mycobacterium infection has not yet been obtained, although systemic steroid therapy has been recommended in recent guidelines. Here we report the case of a 48-year-old Japanese man diagnosed with HIV and disseminated M. genavense infection. His initial CD4-positive T cell count was 3/μL, and his HIV1-RNA viral load was 13,000 copies/mL. He developed IRIS due to disseminated M. genavense infection after two weeks of receiving antiretroviral agents. The patient's serum alkaline phosphatase level, as a barometer of disseminated M. genavense infection in this case, was difficult to control with several anti-mycobacterial agents, although his fever was improved by non-steroidal anti-inflammatory drugs. About five weeks after the onset of IRIS, the patient developed acute left upper quadrant pain and was diagnosed with splenic infarction by contrast-enhanced computed tomography. After the splenic infarction, the patient's serum alkaline phosphatase level decreased without systemic steroid therapy or anticoagulant agents, and his left upper quadrant pain improved naturally within a few days. This case suggests that IRIS due to disseminated M. genavense infection can complicate splenic infarction in patients with HIV, and splenic infarction could improve the IRIS due to disseminated M. genavense infection.

Granulomatous interstitial nephritis on renal biopsy in human immunodeficiency virus positive patients: Prevalence and causes in Cape Town, South Africa

South Africa continues to be burdened by human immunodeficiency virus (HIV) and tuberculosis (TB). In Cape Town, the epidemic of HIV-TB co-infection is as high as 70%. Granulomatous interstitial nephritis (GIN) has increased in frequency on renal biopsy. This study aimed to determine GIN prevalence and causes in HIV-positive patients as well as renal outcomes, patient survival and associated factors. This observational cohort study reviewed HIV-positive renal biopsies for GIN from 2005 to 2012. Causes of GIN (medications, TB, fungal and other), and baseline characteristics were analysed. A comparison of baseline data, renal function and survival was made between GIN and non-GIN cohorts. There were 45/316 biopsies demonstrating GIN. TB was the likely cause of GIN in 27 (60%) and 9 (20%) were due to a drug. Low estimated glomerular filtration rate was a statistically significant factor associated with mortality in both GIN (P = 0.045) and non-GIN cohorts (P < 0.000). In the GIN group, there were 12 (26.7%) deaths. Mortality for all patients was greatest in the first 6 months (P = 0.057). TB co-infection in both cohorts was associated with a higher mortality. The multivariate logistic regression demonstrated that a higher urine protein/creatinine ratio (uPCR) and lower estimated glomerular filtration rate were statistically associated with death. GIN is common in HIV-positive renal biopsies in Cape Town. TB-GIN was the commonest cause and associated with a high early mortality. GIN should be considered in HIV-positive patients with acute kidney injury, its presence conveys a survival benefit. There is a need for improved diagnostic accuracy and treatment strategies of TB-GIN.

Mycobacterium avium complex infection in patients with human immunodeficiency virus: A systematic review and meta-analysis

BACKGROUND

Mycobacterium avium-intracellulare complex (MAC) is one of the leading causes of death among people living with human immunodeficiency virus (HIV). The current study was aimed to determine the frequency of MAC infection in patients infected with HIV.

METHODS

Embase, PubMed, and Web of Science were searched for relevant studies. All statistical analyses were performed by STATA version 14.

RESULTS

From 6,627 retrieved articles, 23 were included in the final analysis. A total of 18,463 patients with HIV were included in the analysis. The frequency of MAC infection in patients with HIV was found to be 10.6% (95% confidence interval, 6.9-14.2).

CONCLUSION

The relatively large fractions of HIV-infected patients were coinfected with MAC, which may poses significant public health problems. Continued progress in the development of rapid diagnostic methods and preventive therapy for MAC should lead to further improvements in survival and quality of life in patients with HIV.

Ten years of antiretroviral therapy: Incidences, patterns and risk factors of opportunistic infections in an urban Ugandan cohort

BACKGROUND

Despite increased antiretroviral therapy (ART) coverage and the raised CD4 threshold for starting ART, opportunistic infections (OIs) are still one of the leading causes of death in sub-Saharan Africa. There are few studies from resource-limited settings on long-term reporting of OIs other than tuberculosis.

METHODS

Patients starting ART between April 2004 and April 2005 were enrolled and followed-up for 10 years in Kampala, Uganda. We report incidences, patterns and risk factors using Cox proportional hazards models of OIs among all patients and among patients with CD4 cell counts >200 cells/μL.

RESULTS

Of the 559 patients starting ART, 164 patients developed a total of 241 OIs during 10 years of follow-up. The overall incidence was highest for oral candidiasis (25.4, 95% confidence interval (CI): 20.5-31.6 per 1000 person-years of follow-up), followed by tuberculosis (15.3, 95% CI: 11.7-20.1), herpes zoster (12.3, 95% CI: 9.1-16.6) and cryptococcal meningitis (3.0, 95% CI: 1.7-5.5). Incidence rates for all OIs were highest in the first year after ART initiation and decreased with the increase of the current CD4 cell count. Factors independently associated with development of OIs were baseline nevirapine-based regimens, time-varying higher viral load, time-varying lower CD4 cell count and time-varying lower hemoglobin. In patients developing OIs at a current CD4 cell count >200 cells/μL, factors independently associated with OI development were time-varying increase in viral load and time-varying decrease in hemoglobin, whereas a baseline CD4 cell count <50 cells/μL was protective.

CONCLUSION

We report high early incidences of OIs, decreasing with increasing CD4 cell count and time spent on ART. Ongoing HIV replication and anemia were strong predictors for OI development independent of the CD4 cell count. Our findings support the recommendation for early initiation of ART and suggest close monitoring for OIs among patients recently started on ART, with low CD4 cell count, high viral load and anemia.

Activated pulmonary tuberculosis in a patient with melanoma during PD-1 inhibition: a case report

Background

PD-1 checkpoint inhibitors have shown a robust tumor response in the treatment of various cancers. Pembrolizumab is an anti-PD-1 checkpoint antibody approved for the treatment of unresectable or metastatic melanoma in more than 40 countries. Although autoimmune pneumonitis is considered a common immune-related adverse event of PD-1 inhibitors, only limited studies have assessed the development of opportunistic infections such as pulmonary tuberculosis (TB).

Case presentation

A patient with metastatic melanoma whose pulmonary TB was activated after administration of pembrolizumab for melanoma is reported. Anti-TB drugs were administered, followed by pembrolizumab (2 mg/kg, repeated every 28 days), which successfully cured the TB and achieved complete response for melanoma.

Conclusion

Activated pulmonary TB was observed during the administration of pembrolizumab. It was safe and effective in the current patient to combine anti-TB drugs and PD-1 inhibitors. More importantly, screening pulmonary TB before administration of PD-1 inhibitors is recommended.

Incidence of tuberculosis in children on antiretroviral therapy: a retrospective cohort study

Objectives

Be aware of the burden of tuberculosis among high-risk population is important. Three hundred fifty-two children were participated in this study. Survival analysis was conducted. We assessed the incidence of tuberculosis and its predictors in children on ART.

Results

Tuberculosis incidence rate in children on ART was 2.63 per 100 person-years. Those children who were on baseline World Health Organization clinical stages 3 and 4 (AHR (adjusted hazard ratio) = 3.0; 95% CI 1.2–7.7), “fair” and “poor” ART adherence (AHR = 4.0; 95% CI 1.5–10.8), late initiation of ART (AHR = 4.0; 95% CI 1.5–10.6), and less than 6 months duration on ART (AHR = 5.5; 95% CI 1.5–20.6) were more likely to develop tuberculosis infection. The incidence rate of TB in children on ART was high. This study suggests a need to give attention to advanced AIDS stages and improve timely initiation of ART and level of adherence to ART.

Epidemiological and clinical profile of HIV-infected patients from Southwestern Goias State, Brazil

Knowledge about epidemiological distribution patterns of HIV infection in different geographic regions is relevant to understand the dynamics of the disease in Brazil. This study aims to characterize the epidemiological and clinical profile of HIV-infected patients from Southwestern Goias State, from 2005 to 2015. A standardized questionnaire was used to collect clinical-epidemiological, virological, and immunological data from the medical records of all HIV-infected patients (n=539) who were followed at the regional reference center of Jatai, Goias State, Brazil, from 2005 to 2015. We detected the prevalence of male patients and the heterosexual route of transmission, as well as an expressive number of young women infected with HIV. The HIV infection was more prevalent in reproductive ages (55.3%). Most patients presented clinical manifestations related to HIV infection at the time of diagnosis. Twenty-four patients presented coinfection with hepatitis C virus, syphilis, hepatitis B virus, leprosy or Chagas disease. Pneumonia caused by Pneumocystis jirovecii was the most common opportunistic infection, followed by neurotoxoplasmosis, tuberculosis, and neurocryptococcosis. Combined antiretroviral therapy improved CD4⁺ T-cell counts: the mean CD4⁺ T-cell counts after treatment was twice as high as those found at the first medical appointment; and highly active antiretroviral therapy promoted viral suppression in a significant number of patients. Considering the increasing distribution of HIV infection to the interior of Brazil, this descriptive study outlines the clinical-epidemiological characteristics of HIV infection in Southwestern Goias and contributes to develop local prevention strategies and public service plans.

Understanding mechanisms underlying the pathology of immune reconstitution inflammatory syndrome (IRIS) by using animal models

Purpose of Review

Despite the increasing number of clinical reports on immune reconstitution inflammatory syndrome (IRIS), mechanistic understanding of IRIS is still largely limited. The main focus of this review is to summarize animal studies, which were performed to better understand the cellular and molecular mechanisms underlying the pathology of IRIS.

Recent Findings

Three IRIS animal models have been reported. They are Mycobacterial IRIS (M-IRIS), cryptococcal IRIS (C-IRIS) and Pneumocystis-IRIS. M-IRIS animal model suggested that, rather than lymphopenia itself, the failure to clear the pathogen by T cells results in excessive priming of the innate immune system. If this happens before T cell reconstitution, hosts likely suffer IRIS upon T cell reconstitution. Interestingly, T cells specific to self-antigens, not only pathogen-specific, could drive IRIS as well.

Summary

The mechanism to develop IRIS is quite complicated, including multiple layers of host immune responses; the innate immune system that detects pathogens and prime host immunity, and the adaptive immune system that is reconstituted but hyper-activated particularly through CD4⁺ T cells. Animal models of IRIS, although there are still small numbers of studies available, have already provided significant insights on the mechanistic understanding of IRIS.

Severe tubulointerstitial nephritis: tracking tuberculosis even in the absence of renal granuloma

Extra-pulmonary tuberculosis is frequently located in the kidneys and, in such cases, could be associated with a granulomatous interstitial nephritis. Granulomas are not always detected, especially in human immunodeficiency virus (HIV)-positive patients. We report here a case of tubulointerstitial nephritis without granulomas in an HIV-negative patient. Since all laboratory tests failed to isolate Mycobacterium tuberculosis in the kidney, a targeted biopsy guided by positron emission tomography-computed tomography was performed on a mediastinal node, revealing a positive culture. After 6 months of treatment, no recovery of the renal injury has been observed.

Imaging features of IRIS caused by AIDS and complicated by tuberculosis

Immune reconstitution inflammatory syndrome (IRIS), a common complication of AIDS, is further complicated by tuberculosis. Its clinical symptoms lack specificity but can be evaluated using diagnostic imaging. High-resolution computed tomography (HRCT) is useful in evaluating the morphology and internal microstructure of lesions associated with the syndrome, as well as the relationship of the internal microstructure with the surrounding tissues. This paper summarizes the present state and progress of imaging research on IRIS caused by AIDS and complicated by tuberculosis.

Immune Reconstitution Inflammatory Syndrome in Patients with AIDS and Disseminated Coccidioidomycosis: A Case Series and Review of the Literature

Coccidioidomycosis causes substantial morbidity and mortality in endemic areas, and dissemination is frequent in patients with impaired cellular immunity such as AIDS. Immune reconstitution inflammatory syndrome (IRIS) is paradoxical clinical worsening after initiation of antiretroviral therapy (ART) in a patient with HIV and a simultaneous opportunistic infection (OI). Immune reconstitution inflammatory syndrome has been well described for a host of mycobacterial, viral, and fungal OIs and malignancies such as Kaposi sarcoma. To date, only 3 cases of IRIS due to coccidioidomycosis have been reported in the literature. At our institution, we report 4 cases of IRIS in HIV-infected patients with disseminated coccidioidomycosis. Unfortunately, all 4 patients died of worsening coccidioidal infection after initiating ART. The optimal timing of ART in patients with AIDS and coccidioidomycosis remains to be elucidated.

A systemic review of tuberculosis with HIV coinfection in children

The epidemiology of tuberculosis is adversely impacted by the human immunodeficiency virus (HIV) coinfection. HIV-infected patients are more prone to opportunistic infections, most commonly tuberculosis, and the risk of death in coinfected patients is higher than in those without HIV. Due to the impaired cellular immunity and reduced immunological response in HIV-infected patients, the classic imaging features of tuberculosis usually seen in patients without HIV may present differently. The aim of this review article is to highlight the imaging features that may assist in the diagnosis of tuberculosis in patients with HIV coinfection.

Mycobacterium bovis BCG and New Vaccines for the Prevention of Tuberculosis

Tuberculosis infects millions of people worldwide and remains a leading global killer despite widespread neonatal administration of the tuberculosis vaccine, bacillus Calmette-Guérin (BCG). BCG has clear and sustained efficacy, but after 10 years, its efficacy appears to wane, at least in some populations. Fortunately, there are many new tuberculosis vaccines in development today, some in advanced stages of clinical trial testing. Here we review the epidemiological need for tuberculosis vaccination, including evolving standards for administration to at risk individuals in developing countries. We also examine proven sources of immune protection from tuberculosis, which to date have exclusively involved natural or vaccine exposure to whole cell mycobacteria. After summarizing evidence for the use and efficacy of BCG, we detail the most promising new candidate vaccines against tuberculosis. The global need for a new tuberculosis vaccine is acute and huge, but clinical trials to be completed in the coming few years are likely either to identify a new tuberculosis vaccine or to substantially reframe how we understand immune protection from this historical scourge.

Tuberculosis and Transplantation

Mycobacterium tuberculosis is a major opportunistic pathogen in transplant recipients. Compared to that in the general population, the frequency of tuberculosis (TB) is 10 to 40 times higher in hematopoietic stem cell transplant (HSCT) recipients and 20 to 74 times higher in solid-organ transplant (SOT) recipients. Transplant recipients with TB are also more likely to develop disseminated disease, have longer time to definitive diagnosis, require more invasive diagnostic procedures, and experience greater anti-TB treatment-related toxicity than the general population. Specific risk factors for TB in SOT recipients include previous exposure to M. tuberculosis (positive tuberculin skin tests and/or residual TB lesions in pretransplant chest X ray) and the intensity of immunosuppression (use of antilymphocyte antibodies, type of basal immunosuppression, and intensification of immunosuppressive therapy for allograft rejection). Risk factors in HSCT recipients are allogeneic transplantation from an unrelated donor; chronic graft-versus-host disease treated with corticosteroids; unrelated or mismatched allograft; pretransplant conditioning using total body irradiation, busulfan, or cyclophosphamide; and type and stage of primary hematological disorder. Transplant recipients with evidence of prior exposure to M. tuberculosis should receive treatment appropriate for latent TB infection. Optimal management of active TB disease is particularly challenging due to significant drug interactions between the anti-TB agents and the immunosuppressive therapy. In this chapter, we address the epidemiology, clinical presentation, diagnostic considerations, and management strategies for TB in SOT and HSCT recipients.