Prospective Pilot Study of Cyclophosphamide as an Adjunct Treatment in Patients With Adult-Onset Immunodeficiency Associated With Anti-interferon-γ Autoantibodies

From Mendel to mycoses: Immuno-genomic warfare at the human-fungus interface

Fungi are opportunists: They particularly require a defect of immunity to cause severe or disseminated disease. While often secondary to an apparent iatrogenic cause, fungal diseases do occur in the absence of one, albeit infrequently. These rare cases may be due to an underlying genetic immunodeficiency that can present variably in age of onset, severity, or other infections, and in the absence of a family history of disease. They may also be due to anti-cytokine autoantibodies. This review provides a background on how human genetics or autoantibodies underlie cases of susceptibility to severe or disseminated fungal disease. Subsequently, the lessons learned from these inborn errors of immunity marked by fungal disease (IEI-FD) provide a framework to begin to mechanistically decipher fungal syndromes, potentially paving the way for precision therapy of the mycoses.

Multiple intracellular pathogen infections with ocular pathologies associated with adult-onset immunodeficiency due to anti-interferon-γ autoantibodies: a case report

BACKGROUND

Autoantibodies against interferon-γ (IFN-γ) can inhibit IFN-γ-dependent signal transducer and activator of transcription 1 phosphorylation and thus increase the risk of infection with intracellular pathogens, such as Talaromyces marneffei (TM), nontuberculous mycobacteria (NTMs), and Mycobacterium tuberculosis (TB). Here, we report a rare case of triple infection caused by TM, NTM, and TB in a human immunodeficiency virus-negative patient.

CASE PRESENTATION

A middle-aged female was admitted to our hospital after experiencing recurrent rash, cough, and expectoration for 4 months. She was successively diagnosed with NTM, TM, and TB infections without conventional immunosuppression-associated factors. However, after effective anti-infective treatment, the patient was confirmed to have allergic conjunctivitis and was successfully treated with corticosteroids and immunosuppressants. The most conspicuous characteristics were recurrent infection and immune disorders.

CONCLUSIONS

High-titer anti-IFN-γ autoantibodies are strongly associated with severe and disseminated infections, such as NTM, TM, and TB. It is characterized by persistently high degree of inflammation and high immunoglobin levels.

Anticytokine Autoantibodies in Infectious Diseases: A Practical Overview

Anticytokine autoantibodies (ACAAs) are a fascinating group of antibodies that have gained more and more attention in the field of autoimmunity and secondary immunodeficiencies over the years. Some of these antibodies are characterized by their ability to target and neutralize specific cytokines. ACAAs can play a role in the susceptibility to several infectious diseases, and their infectious manifestations depending on which specific immunological pathway is affected. In this review, we will give an outline per infection in which ACAAs might play a role and whether additional immunomodulatory treatment next to antimicrobial treatment can be considered. Finally, we describe the areas for future research on ACAAs.

Prevalence and clinical manifestations of cutaneous findings in patients with adult-onset immunodeficiency due to anti-interferon gamma autoantibodies: an eight-year retrospective study

BACKGROUND

Cutaneous findings in adult-onset immunodeficiency due to anti-interferon gamma autoantibodies (anti-IFN-γ autoAbs) are common. Currently, data on this topic are scarce.

METHODS

We retrospectively reviewed medical records of 202 skin episodes from 77 patients diagnosed with adult-onset immunodeficiency due to anti-IFN-γ autoAbs. The exclusion of drug eruptions left 180 episodes from 74 patients for further analysis.

RESULTS

Reactive dermatosis was diagnosed in 66.1%, followed by disseminated skin infection (18.3%) and local skin infection (15.6%). Neutrophilic dermatosis (ND) tended to appear on the upper part of bodies, while leg lesions were common in the non-ND. Disseminated infection occurred more frequently with ND. Mycobacterium abscessus was the most common pathogen of concomitant infection. Remission was achieved in 21.6% and was significantly associated with females.

CONCLUSION

Reactive dermatosis was the most common skin manifestation. ND was found in the upper part of bodies and associated with disseminated infection. Drug-free remission was scarcely achieved.

Characteristics and Outcomes of Anti-interferon Gamma Antibody-Associated Adult Onset Immunodeficiency

PURPOSE

Anti-interferon gamma antibody (AIGA) is a rare cause of adult onset immunodeficiency, leading to severe disseminated opportunistic infections with varying outcomes. We aimed to summarize the disease characteristics and to explore factors associated with disease outcome.

METHODS

A systematic literature review of AIGA associated disease was conducted. Serum-positive cases with detailed clinical presentations, treatment protocols, and outcomes were included. The patients were categorized into controlled and uncontrolled groups based on their documented clinical outcome. Factors associated with disease outcome were analyzed with logistic regression models.

RESULTS

A total of 195 AIGA patients were retrospectively analyzed, with 119(61.0%) having controlled disease and 76 (39.0%) having uncontrolled disease. The median time to diagnosis and disease course were 12 months and 28 months, respectively. A total of 358 pathogens have been reported with nontubercular mycobacterium (NTM) and Talaromyces marneffei as the most common pathogens. The recurrence rate was as high as 56.0%. The effective rates of antibiotics alone, antibiotics with rituximab, and antibiotics with cyclophosphamide were 40.5%, 73.5%, and 75%, respectively. In the multivariate logistic analysis, skin involvement, NTM infection, and recurrent infections remained significantly associated with disease control, with ORs of 3.25 (95% CI 1.187 ~ 8.909, P value = 0.022), 4.74 (95% CI 1.300 ~ 17.30, P value = 0.018), and 0.22 (95% CI 0.086 ~ 0.551, P value = 0.001), respectively. The patients with disease control had significant AIGA titer reduction.

CONCLUSIONS

AIGA could cause severe opportunistic infections with unsatisfactory control, particularly in patients with recurrent infections. Efforts should be made to closely monitor the disease and regulate the immune system.

Health related quality of life in anti interferon γ autoantibody associated immunodeficiency syndrome measured with EQ5D5L and SF36

The anti-IFN-γ disease is a rare condition characterized by recurrent and persistent infections, potentially impacting the quality of life (QoL). However, comprehensive data on QoL in this population are lacking. This study aims to evaluate the QoL of Anti-IFN-γ patients compared to healthy control and explore potential differences in QoL between patients in the active and remission stages. A cross-sectional study design was conducted, recruiting 38 Anti-IFN-γ patients and 38 sex- and age-matched healthy controls. QoL assessment utilized the 5-level EuroQol-5 Dimension (EQ-5D-5L) and the 36-Item Short Form Health Survey (SF-36). The Anti-IFN-γ group had a mean age of 57.37 (± 10.32) years, with females comprising 60.53%. Among the Anti-IFN-γ patients, 55.26% were classified as having active disease. 63% of Anti-IFN-γ patients received Immunosuppressive treatments. Anti-IFN-γ disease exhibited a significant negative impact on HRQoL, as evidenced by lower utility scores in EQ-5D-5L and lower physical and mental component scores in SF-36 across various domains, including physical function, role physical, general health, bodily pain, social functioning, role emotion and mental health, compared to healthy controls. Additionally, patients in the active disease displayed lower scores in multiple domains, including bodily pain, general health, role emotion and mental health, and a lower utility score in EQ-5D-5L compared to patients in remission. The anti-IFN-γ disease significantly impairs the HRQoL of affected individuals compared to healthy controls. However, effective treatment leading to remission holds promise for improving the HRQoL of patients with Anti-IFN-γ disease.

Anticytokine Autoantibodies and Fungal Infections

Anticytokine autoantibodies (ACAAs) can cause adult onset immunodeficiencies which mimic primary immunodeficiencies and can present as refractory and severe fungal infections. This paper provides an overview of the role of innate immunity, including key cytokines, in fungal infections and then describes four clinical scenarios where ACAAs are associated with severe presentations of a fungal infection: (1) Talaromyces marneffei infection and anti-interferon-γ, (2) histoplasmosis and anti-interferon-γ, (3) Cryptococcus gattii infection and anti-GM-CSF, and (4) mucocutaneous candidiasis and anti-IL-17A/F (IL-22). Testing for ACAAs and potential therapeutic options are discussed.

Mixed Mycobacterium kansasii and Mycobacterium smegmatis infection in an adult-onset immunodeficiency patient with anti-interferon-γ autoantibodies

Anti-interferon-gamma autoantibody (AIGA) is a rare adult-onset immunodeficiency disease that increases the risk of occult infection. Nontuberculous mycobacteria (NTM) infections represent a diverse group of species and subspecies, and mixed infections with two or more NTM species have been reported. However, there is no consensus on the optimal antibiotics or immune modulator treatments for mixed NTM infections in AIGA patients. Here, we present the case of a 40-year-old female who initially presented with suspected lung cancer with obstructive pneumonitis. Tissue samples obtained through bronchoscopy, endoscopy, and bone marrow biopsy revealed disseminated mycobacterium infection. PCR-based testing confirmed a mixed pulmonary infection with Mycobacterium kansasii and Mycobacterium smegmatis, as well as M. kansasii bacteremia. The patient received 12 months of anti-NTM medications for M. kansasii, and the symptoms improved. Additionally, the images showed resolution after 6 months, even without the need for immune modulator treatment.

High-titer anti-interferon-γ neutralizing autoantibodies linked to opportunistic infections in patients with adult-onset still's disease

Objective

Neutralizing anti-interferon (IFN)-γ autoantibodies are linked to opportunistic infections (OIs). To explore the association between anti-IFN-γ autoantibodies and OIs in patients with adult-onset Still's disease (AOSD), we aimed to examine the ability of these autoantibodies to blockade signal transducer and activator of transcription (STAT1)-phosphorylation and chemokines production.

Methods

Serum titers of anti-IFN-γ autoantibodies were quantified using ELISA in 29 AOSD and 22 healthy controls (HC). The detectable autoantibodies were verified with immunoblotting assay, and their neutralizing capacity against IFN-γ-signaling was evaluated with flow-cytometry analysis and immunoblotting. IFN-γ-mediated production of supernatant chemokines, including monocyte chemoattractant protein-1 (MCP-1) and IFN-γ inducible protein-10 (IP-10), were measured by ELISA.

Results

Among 29 AOSD patients, high titers of anti-IFN-γ neutralizing autoantibodies were detectable in two patients with OIs. Immunoblotting assay revealed more effective inhibition of STAT1-phosphorylation in THP-1 cells treated with sera from autoantibody-positive AOSD patients (56.7 ± 34.79%) compared with those from HC (104.3 ±29.51%), which was also demonstrated in flow-cytometry analysis (47.13 ± 40.99 vs. 97.92 ± 9.48%, p < 0.05). Depleted serum IgG from anti-IFN-γ autoAbs-positive AOSD patients with OIs restored phosphorylated STAT-1 upon IFN-γ treatment. Sera from autoantibody-positive AOSD patients more effectively inhibited IFN-γ-mediated production of MCP-1 (45.65 pg/ml) and IP-10 (22.44 pg/ml) than sera from HC (263.1 pg/ml and 104.0 pg/ml, both p < 0.05). Serum samples showing the strongest inhibition of IFN-γ-signaling were from two patients with high-titer autoantibodies and OIs.

Conclusion

AOSD patients have a high positive rate and titers of anti-IFN-γ autoantibodies. The remarkable blockade effect of high-titer autoantibodies on IFN-γ-mediated STAT1-phosphorylation and chemokines could make these patients susceptible to OIs.

Pathogen spectrum and immunotherapy in patients with anti-IFN-γ autoantibodies: A multicenter retrospective study and systematic review

Background

Anti-interferon-γ autoantibody (AIGA) positivity is an emerging immunodeficiency syndrome closely associated with intracellular infection in individuals without human immunodeficiency virus (HIV). However, the information on epidemiology, pathogen spectrum, and immunotherapy among these patients lack a systematic description of large data.

Methods

This systematic literature review and multicenter retrospective study aimed to describe the pathogen spectrum and review treatment strategies among patients with AIGA positivity.

Results

We included 810 HIV-negative patients with AIGA positivity infected with one or more intracellular pathogens. Excluding four teenagers, all the patients were adults. The most common pathogen was nontuberculous mycobacteria (NTM) (676/810, 83.5%). A total of 765 NTM isolates were identified in 676 patients with NTM, including 342 (44.7%) rapid-grower mycobacteria, 273 (35.7%) slow-grower mycobacteria, and 150 (19.6%) unidentified NTM subtype. Even with long-term and intensive antimicrobial treatments, 42.6% of patients with AIGA positivity had recurrence and/or persistent infection. Sixty-seven patients underwent immunoregulatory or immunosuppressive therapy, and most (60) achieved remission. The most common treatment strategy was rituximab (27/67, 40.3%) and cyclophosphamide (22/67, 32.8%), followed by cyclophosphamide combined with glucocorticoids (8/67, 11.9%).

Conclusions

Intracellular pathogen was the most common infection in patients with AIGA positivity. The predominant infection phenotypes were NTM, varicella-zoster virus, Talaromyces marneffei, and Salmonella spp., with or without other opportunistic infections. AIGA immunotherapy, including rituximab or cyclophosphamide, has yielded good preliminary results in some cases.

Intravenous Cyclophosphamide Therapy for Anti-IFN-γ Autoantibody-Associated Talaromyces marneffei Infection

High titers of anti-interferon-γ autoantibodies (AIGAs) are an important factor leading to persistent, relapsed, and refractory infections in HIV-negative hosts infected with Talaromyces marneffei (TM). We report 5 patients treated with pulses of high-dose intravenous cyclophosphamide (IVCY) who were followed for 2 years. Before IVCY therapy, all patients had multiple relapses, with a median (interquartile range [IQR]) of 2 (1-3) instances of relapse. The median serum AIGA titers (IQR) were 58 753 (41 203-89 605) ng/mL at diagnosis, 48 189.4 (15 537-83 375) ng/mL before IVCY therapy, and 10 721.2 (5637-13 245) ng/mL at the end of IVCY therapy (P < .05). After 3 months of follow-up, the median AIGA titers (IQR) rose gradually to 21 232.6 (9896-45 626) ng/mL, and to 37 464.2 (19 872-58 321) ng/mL at 24 months (P < .05). Five patients discontinued antimicrobial therapy within 3-12 months after completion of IVCY therapy, but only 1 patient had a relapse. In conclusion, pulses of short-term and high-dose IVCY can effectively reduce AIGA titers.

Periocular Infection of Mycobacterium avium Complex in a Patient with Interferon-γ Autoantibodies: A Case Report

The neutralizing anti-interferon-γ autoantibody (nAIGA)-associated immunodeficiency is an emerging entity frequently associated with the nontuberculosis mycobacterium (NTM) infection and other opportunistic infections. We present a female patient with a mysterious periocular Mycobacterium avium complex (MAC) infection, accompanied by sequential opportunistic infections including Salmollelosis and herpes zoster infection. Her condition stabilized after long-term antimycobacterial treatment. Nevertheless, neutralizing anti-interferon-γ autoantibody was found in her serum, which was compatible with the scenario of adult-onset immunodeficiency.

Sweet’s Syndrome Accompanied by Coinfection with Multiple Pathogens and Disseminated Mycobacterium phlei Infection Presenting with Osteolytic Destruction During 12 Years of Follow-Up: A Rare Case Report

Background

Anti-IFN-γ autoantibodies (AIGAs) are closely related to the disseminated infection of multiple pathogens. Mycobacterium phlei (M. phlei) is a nonpathogenic nontuberculous mycobacteria (NTM), and M. phlei infection of the bone is extremely rare. We report a rare case of high-titer AIGAs presenting with Sweet’s syndrome (SS) accompanied by opportunistic coinfection with multiple pathogens during 12 years of follow-up. The patient in this case also developed disseminated M. phlei infection with osteolytic destruction after treatment for SS.

Case Presentation

A 68-year-old Chinese woman was admitted to our hospital in August 2009 due to fever and cough with expectoration for 3 months. The patient was successively infected with Klebsiella pneumoniae, herpes zoster virus and Candida. Chest computed tomography (CT) showed recurrent consolidations in different lung fields. After 15 months of antimicrobial treatment, the patient experienced partial recovery. In September 2010, the patient was pathologically diagnosed with SS due to the presence of multiple rashes. After prednisone and thalidomide treatment, the rashes subsided, and the pulmonary lesions had completely absorbed. In May 2011, the patient was diagnosed with disseminated tuberculosis and was administered anti-tuberculosis therapy for 3 months without improvement. NTM was subsequently cultured from her sputum and chest wall pus, and she improved after 20 months of anti-NTM therapy. In March 2016, the patient developed osteolytic destruction of the C7-T2 vertebral bodies with a back abscess. NTM was eventually cultured from the dorsal abscess pus and further identified as M. phlei. High-titer AIGAs were detected in the patient’s serum. After another round of aggressive anti-NTM therapy, the patient was finally cured.

Conclusion

Patients with AIGA-associated anti-cytokine autoantibody disease can present with multiple opportunistic infections and SS involving the lung. AIGA-associated immunodeficiency leads to infection with nonpathogenic M. phlei, which is refractory, can cause relapse, and even leads to osteolytic destruction.

Anticytokine autoantibodies: Autoimmunity trespassing on antimicrobial immunity

Anticytokine autoantibodies can cause immunodeficiency or dysregulate immune responses. They may phenocopy genetically defined primary immunodeficiencies. We review current anti-type 1 and anti-type 2 interferon; anti-IL-12/23, anti-IL-17, and anti-GM-CSF autoantibodies; HLA associations; disease associations; and mechanistically based treatment options. Suspecting the presence of these autoantibodies in patients and identifying them at the onset of symptoms should ameliorate disease and improve outcomes.

Anti-interferon-γ autoantibody-associated immunodeficiency

Anticytokine autoantibodies are an emerging disease etiology, through the disturbance of physiological functions of cognate cytokines. Anti-interferon (IFN)-γ autoantibodies (AIGAs) were first identified in patients with severe mycobacterial infections, and were considered to be an autoimmune phenocopy of inborn genetic errors of the IL-12/IFN-γ axis. More than 600 reported cases, most originating from Southeast Asia, have been diagnosed over the last decade. Specific HLA class II molecules are associated with these autoantibodies, which provide a genetic basis for the high prevalence of this immunodeficiency syndrome in certain ethnic groups. Salmonellosis and herpes zoster reactivation are observed in more than half the patients with AIGAs. Moreover, AIGAs have been shown to underlie severe Taralomyce marneffei infection in HIV-negative patients. AIGAs may, thus, be considered a new form of late-onset immunodeficiency conferring a predisposition not only to severe mycobacterial, but also to some bacterial and fungal infections.

Treatment Dilemmas in Disseminated Nontuberculous Mycobacterial Infections With Interferon-gamma Autoantibodies

Disseminated Mycobacterium avium complex (dMAC) is typically seen in individuals with impaired cell-mediated immunity and is best described in those with HIV. Recently, cases have been described in otherwise healthy individuals with neutralizing antibodies to interferon-gamma (nIFNγ-autoAb), especially in patients of Southeast Asian descent. Treatment is often refractory to mycobacterial therapies, and the use of rituximab and other immunomodulatory agents has been explored. We report 3 cases of dMAC with nIFN-γ-autoAb and review the available literature on treatment strategies to provide a framework for the management of patients with refractory infections in the context of neutralizing antibodies to interferon-gamma.

Clinical findings of Talaromyces marneffei infection among patients with anti-interferon-γ immunodeficiency: a prospective cohort study

Background

Talaromyces marneffei (T. marneffei) infection has been associated with adult-onset immunodeficiency due to anti-IFN-γ autoantibodies. We aimed to investigate the clinical features of non-HIV-infected patients with T. marneffei infection in southern China.

Methods

Between January 2018 and September 2020, we enrolled patients with T. marneffei infection who were HIV-negative (group TM, n = 42), including anti-IFN-γ autoantibody-positive (group TMP, n = 22) and anti-IFN-γ autoantibody-negative (group TMN, n = 20) patients and healthy controls (group HC, n = 40). Anti-IFN-γ autoantibodies were detected by ELISA. Clinical characteristics and clinical laboratory parameters were recorded.

Results

Compared with anti-IFN-γ autoantibody-negative patients with T. marneffei infection, anti-IFN-γ autoantibody-positive patients did not have underlying respiratory disease; more frequently exhibited dissemination of systemic infections with severe pleural effusion; had higher WBC counts, C-reactive protein levels, erythrocyte sedimentation rates, and neutrophil and CD8⁺ T cell counts; had lower hemoglobin levels; and were more likely to have other intracellular pathogen infections. Most of these patients had poor outcomes despite standardized antimicrobial therapy.

Conclusion

T. marneffei-infected patients with higher anti-IFN-γ autoantibody titers have more severe disease and complex clinical conditions.

Talaromyces marneffei and Burkholderia cepacia Co-Infection in a HIV-Uninfected Patient with Anti-Interferon-γ Autoantibodies

A high titer of neutralizing anti-interferon-γ autoantibodies can cause immunodeficiency associated with severe or disseminated infections caused by Talaromyces marneffei in human immunodeficiency virus-negative patients. Herein, we reported a rare case of disseminated Talaromyces marneffei and Burkholderia cepacia infection. The patient’s lungs, lymph nodes, and bronchi were involved, and he had neck abscesses and osteomyelitis. We measured the neutralizing anti-interferon-γ autoantibodies in the peripheral blood and found that the patient had a persistently high positive titer. Despite aggressive treatment, the patient developed disseminated intravascular coagulation and died. Thus, high-titer nAIGAs may be associated with multiple opportunistic, persistent and disseminated infections.

R-CHOP Chemotherapy for Disseminated Mycobacterium avium Complex Disease due to Anti-Interferon-Gamma Autoantibodies: A Case Report

A 77-year-old Japanese man with disseminated Mycobacterium avium complex (MAC) disease due to anti-interferon-gamma autoantibodies received rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisolone (R-CHOP) chemotherapy because of non-Hodgkin lymphoma complication. The hepatobiliary nodules due to MAC resolved with R-CHOP and multidrug antimycobacterial treatment. R-CHOP could serve as an alternative adjunctive therapy for patients with anti-interferon-gamma autoantibodies.

Coinfection by Talaromyces marneffei and Mycobacterium abscessus in a human immunodeficiency virus-negative patient with anti-interferon-γ autoantibody: a case report

Patients with anti-interferon (IFN)-γ autoantibodies have weakened immune defenses against intracellular pathogens. Because of its low incidence and non-specific symptoms, diagnosis of anti-IFN-γ autoantibody syndrome is difficult to establish during the early stages of infection. Here, we report a patient with high titers of serum anti-IFN-γ autoantibodies suffering from opportunistic infections. The patient presented with intermittent fever for 2 weeks. During his first hospitalization, he was diagnosed with Talaromyces marneffei pulmonary infection and successfully treated with antifungal therapy. However, multiple cervical lymph nodes subsequently became progressively enlarged. Mycobacterium abscessus infection was confirmed by positive cervical lymph node tissue cultures. High-titer serum anti-IFN-γ antibodies were also detected. Following anti-M. abscessus therapy, both his symptoms and lymph node lymphadenitis gradually improved. Anti-IFN-γ autoantibody syndrome should be considered in adult patients with severe opportunistic coinfections in the absence of other known risk factors.

Minireview: Insights into anti-interferon-γ autoantibodies

The association between the presence of anti-interferon-γ autoantibodies and the onset of immunodeficiency with intracellular infections has been clearly established. No standard regimen to control the production of these pathogenic autoantibodies, apart from antimicrobial therapy to eliminate infections, contributes to the medical burden of this syndrome, which sometimes has a fatal outcome. In this review, we summarize the findings on anti-interferon-γ autoantibodies to facilitate further research and to provide guidance for treatment strategies.