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

Deepening Understanding of the Clinical Features and Diagnostic Approaches to Anti-Interferon-Gamma Autoantibody Associated Adult-Onset Immunodeficiency in the Last 20 Years: A Case Report and Literature Review

Anti-interferon-gamma autoantibody (AIGA)-associated adult-onset immunodeficiency (AOID) is an emerging disease that can lead to serious opportunistic infections, which has a history of 20 years since it was first reported in 2004. It's a hard-detected AOID caused by AIGA. In recent years, there has been an increasing number of reports on the disease, but there is still a lack of consensus on the diagnosis and treatment. We here report a case of a 70-year-old Chinese male who had had AIGA in serum and suffered from recurrent pyothorax. Although his condition improved with antimicrobial therapy each time, his pyothorax frequently relapsed, requiring repeated hospitalizations. A literature review of AIGA-associated AOID was conducted. We searched PubMed, Web of Science, Embase, and the Chinese literature database for manuscripts concerning AIGA. Cases detected with AIGA and met our criteria were included. A total of 502 patients were retrospectively analyzed, with 256 (51.0%) males and 246 (49.0%) females. The majority of patients are from Southeast Asia (98.2%). Lymph node (83.7%) is the most commonly involved organ, followed by the lung (60.6%). Nontuberculous mycobacteria (NTM) was identified as the predominant pathogen reported in 77.49% of the patients. The clinical manifestations are diverse and non-specific for the disease often presenting with multi-organ involvement and multiple infections. Timely identification of patients with AIGA, appropriate diagnosis, and individualized treatment are critical; thus, we propose a reasonable diagnostic criterion and a structured diagnostic and treatment process based on our findings to provide clinicians with comprehensive information for clinical practice.

Disseminated talaromycosis in HIV-negative patients with lung cancer: a rare case report and literature review

BACKGROUND

Talaromycosis has long been considered to be exclusively associated with human immunodeficiency virus/acquired immune deficiency syndrome (HIV/AIDS). In recent years, with effective control measures for HIV, the number of talaromycosis patients without HIV infection has been increasing annually. All of these patients have various immunosuppressive factors, including tumors. However, we find that talaromycosis among HIV-negative lung cancer patients remains a rarity and is without comprehensive reviews, contributing to significant gaps in clinical knowledge.

CASE PRESENTATION

We report a case of lung squamous cell carcinoma combined with Talaromyces marneffei (T.marneffei) infection in an HIV-negative patient. The patient, a male with a history of long-term smoking, presented with recurrent fever and cough. Chest computed tomography (CT) scans revealed pleural effusion and nodules. The patient was diagnosed with lung squamous cell carcinoma and talaromycosis through sputum cytology and blood/cerebrospinal fluid metagenomics next-generation sequencing (mNGS). The patient underwent only antifungal therapy and succumbed to respiratory failure, liver and kidney failure, and sepsis in January 2024, before receiving any anti-tumor therapy.

CONCLUSION

The mortality rate of talaromycosis combined with lung cancer is extremely high. Therefore, regardless of whether patients have a history of travel to endemic areas of T. marneffei infection, it is crucial to test for HIV and anti-IFN-γ autoantibodies (AIGA) in patients suspected of having a pulmonary fungal infection, as well as conducting multiple cultures of specimens from different sites and utilizing mNGS to enhance diagnostic accuracy. Additionally, it is essential to perform biopsies in various methods from multiple sites to ascertain the presence of lung cancer. With effective control of T. marneffei infection and timely diagnosis and treatment of lung cancer, there can be a significant improvement in patient survival rates.

Anti-cytokine autoantibodies in human susceptibility to infectious diseases: insights from Inborn errors of immunity

The study of Inborn Errors of Immunity (IEIs) is critical for understanding the complex mechanisms of the human immune response to infectious diseases. Specific IEIs, characterized by selective susceptibility to certain pathogens, have enhanced our understanding of the key molecular pathways and cellular subsets involved in host defense against pathogens. These insights revealed that patients with anti-cytokine autoantibodies exhibit phenotypes similar to those with pathogenic mutations in genes encoding signaling molecules. This new disease concept is currently categorized as 'Phenocopies of IEI'. This category includes anti-cytokine autoantibodies targeting IL-17/IL-22, IFN-γ, IL-6, GM-CSF, and type I IFNs. Abundant anti-cytokine autoantibodies deplete corresponding cytokines, impair signaling pathways, and increase susceptibility to specific pathogens. We herein demonstrate the clinical and etiological significance of anti-cytokine autoantibodies in human immunity to pathogens. Insights from studies of rare IEIs underscore the pathological importance of cytokine-targeting autoantibodies. Simultaneously, the diverse clinical phenotype of patients with these autoantibodies suggests that the influences of cytokine dysfunction are broader than previously recognized. Furthermore, comprehensive studies prompted by the COVID-19 pandemic highlighted the substantial clinical impact of autoantibodies and their potential role in shaping the outcomes of infectious disease.

Using structure-function information from IFN-γ-binding proteins and biased agonists to uncouple immunostimulatory and immunosuppressive activities

IFN-γ is a pleiotropic antiviral cytokine that coordinates innate and adaptive immune responses and induces both immunostimulatory and immunosuppressive activities, limiting its use in the clinic. Due to its antiviral role, several viruses express proteins that bind IFN-γ, blocking its interaction with the IFN-γ receptor (IFNGR). However, varicella zoster virus glycoprotein C binds IFN-γ and induces the expression of a subset of specific ISGs, similar to biased IFN-γ agonists generated based on the crystal structure of the IFN-γ - IFNGR complex. Here, we propose using structural and mechanistic information from viral proteins and biased agonists to design novel IFN-γ agonists that fine-tune IFN-γ - IFNGR activity, reducing the immunosuppressive and toxic effects of this cytokine.

Pathogen spectrum and clinical characteristics of lung cancer patients: A 10-year retrospective study

Infection is the most common non-cancer cause of death in patients with lung cancer (LC). However, original research reports with large sample sizes on the epidemiology, pathogen spectrum, immune status changes, and prognosis of these patients are lacking. A retrospective study of LC patients with infection was performed at Guangxi Medical University Cancer Hospital from 2014 to 2023. In total, 699 LC patients with disease complicated by infection were included in the study. The incidence of infection increased from 4.61% in 2014 to 9.77% in 2023 among patients with LC. A total of 109 types of pathogens were detected. The most prevalent pathogenic organisms in each category were bacteria (Klebsiella pneumoniae and Escherichia coli), fungi (Candida spp. and Aspergillus spp.), viruses (COVID-19 and Epstein-Barr virus), and special pathogens (Mycobacterium tuberculosis and Mycoplasma pneumoniae). Upon diagnosis of infection, the total T lymphocyte, helper T cell, Th/Ts ratio, and B lymphocyte counts decreased, while the natural killer cell and suppressor T-cell counts increased. Infection is a crucial risk factor affecting the prognosis and mortality of patients with LC. The susceptibility of patients with LC to infection may be related to immunodeficiency resulting from antitumor treatment and disease progression.

Disseminated Histoplasmosis Due to Anti-IFN-γ Autoantibodies-Associated Immunodeficiency

Background

Disseminated histoplasmosis caused by the temperature-dependent dimorphic fungus Histoplasma capsulatum is an invasive fungal disease rarely reported in southern China. Here, we report a case of disseminated histoplasmosis due to anti-IFN-γ autoantibodies (AIGA)- associated immunodeficiency.

Case Presentation

We present the case of a 57-year-old HIV-negative female patient with disseminated histoplasmosis in southern China. The patient showed progressively enlarging multiple clavicular, neck, and upper chest skin nodules and dyspnea, which led to the initial suspicion of pulmonary tuberculosis or lung cancer. Bacterial cultures results were negative. Histopathology of a skin tissue showed infectious granulomas. Disseminated histoplasmosis was diagnosed via next-generation sequencing (mNGS) and fungal culture. Furthermore, enzyme-linked immunosorbent assay results from a peripheral blood confirmed that the patient had a high-titer of AIGA.

Conclusion

This case prompts clinicians to consider histoplasmosis an important differential diagnosis in a region where talaromycosis is highly endemic. This case report emphasizes that clinicians should be vigilant for immunodeficiency and consider testing for AIGA in HIV-negative patients who are suspected of having complex opportunistic infections.

Clinical characteristics of acquired anti-IFN-γ autoantibodies in patients infected with non-tuberculous mycobacteria: a prospective cohort study

BACKGROUND

Patients with positive anti-IFN-γ autoantibodies (AIGAs) are characterized by susceptibility to disseminated infection by multiple pathogens. The clinical characteristics of non-tuberculous mycobacterial (NTM) infection with AIGAs positivity remain unclear.

METHODS

A prospective cohort study was conducted at the First Affiliated Hospital of Guangxi Medical University from January 2021 to January 2024. A total of 93 patients diagnosed with NTM infection were divided into two groups: AIGAs-positive with NTM infection and AIGAs-negative with NTM infection. The clinical manifestations, laboratory data, imaging examination, and pathogens were analyzed to characterize the disease.

RESULTS

A total of 44 AIGAs-positive and 49 AIGAs-negative patients with NTM infection were enrolled. Disseminated infections were significantly more common among AIGAs-positive patients (P < 0.001), with frequent co-infections involving Talaromyces marneffei (TM) and viruses. Additionally, AIGAs-positive patients exhibited elevated inflammatory markers and immunoglobulins. In the AIGAs-positive group, lymph nodes, bones, skin, and blood were the most frequently affected sites. Chest CT scans exhibited a range of findings. Over a mean follow-up period of 36 months, 56.82% of patients with AIGAs positivity experienced exacerbations despite undergoing regular anti-NTM therapy.

CONCLUSIONS

AIGAs-positive patients with NTM infection exhibit elevated inflammatory markers, abnormal immune indicators, and coagulation function. Disseminated infections involving multiple organs are common, with frequent co-infection with TM and viruses. These patients may have unique symptoms, signs, and imaging findings compared to AIGAs-negative patients. Recurrence is common among these patients, highlighting the need for timely identification and intervention.

Clinical Characteristics Analysis of 30 Cases of Interferon-γ Autoantibody-Positive Patients with Concurrent Mycobacterial Infection: A 6-Year Retrospective Study

Purpose

This study aimed to investigate and elucidate the clinical characteristics, immune status, infection types and patterns, treatment responses, and disease progression in patients with positive anti-interferon-gamma (IFN-γ) autoantibodies in combination with Mycobacterium infections.

Patients and Methods

We conducted a retrospective analysis of clinical data from patients with positive anti-IFN-γ autoantibodies and concurrent Mycobacterial infections, including Mycobacterial infections (MTB) and non-tuberculous mycobacteria (NTM). The study included cases treated at the Fourth People's Hospital of Nanning, Guangxi, from 2018 to 2023. Data collected comprised symptoms, clinical signs, laboratory test results, imaging findings, and other relevant clinical information. Patients were also followed up to evaluate treatment responses and long-term therapeutic outcomes.

Results

A total of 30 patients with MTB and NTM infections were analyzed. The majority presented with common symptoms, such as cough, sputum production, weight loss, extrapulmonary tuberculosis (TB), and a range of opportunistic infections. Laboratory and imaging studies revealed complex infection patterns and various pathological changes. Treatment primarily involved targeted anti-infective therapy combined with immunosupportive measures. However, frequent treatment relapses and side effects were observed, resulting in two deaths.

Conclusion

Immune deficiency associated with positive anti-IFN-γ autoantibodies resembles the immunosuppression seen in advanced stages of human immunodeficiency virus/acquired immune deficiency syndrome (HIV/AIDS), rendering patients highly susceptible to opportunistic infections. These infections were predominantly caused by NTM, followed by MTB and Talaromyces marneffei (TM). This represents a novel immune deficiency syndrome that predisposes patients to a spectrum of opportunistic infections.

Interferon Upregulation Associates with Insulin Resistance in Humans

In humans, insulin resistance is a physiological response to infections developed to supply sufficient energy to the activated immune system. This metabolic adaptation facilitates the immune response but usually persists after the recovery period of the infection and predisposes the hosts to type 2 diabetes and vascular injury. In patients with diabetes, superimposed insulin resistance worsens metabolic control and promotes diabetic ketoacidosis. Pathogenic mechanisms underlying insulin resistance during microbial invasions remain to be fully defined. However, interferons cause insulin resistance in healthy subjects and other population groups, and their production is increased during infections, suggesting that this group of molecules may contribute to reduced insulin sensitivity. In agreement with this notion, gene expression profiles (transcriptomes) from patients with insulin resistance show a robust overexpression of interferon- stimulated genes (interferon signature). In addition, serum levels of interferon and surrogates for interferon activity are elevated in patients with insulin resistance. Circulating levels of interferon- γ-inducible protein-10, neopterin, and apolipoprotein L1 correlate with insulin resistance manifestations, such as hypertriglyceridemia, reduced HDL-c, visceral fat, and homeostasis model assessment-insulin resistance. Furthermore, interferon downregulation improves insulin resistance. Antimalarials such as hydroxychloroquine reduce interferon production and improve insulin resistance, reducing the risk for type 2 diabetes and cardiovascular disease. In addition, diverse clinical conditions that feature interferon upregulation are associated with insulin resistance, suggesting that interferon may be a common factor promoting this adaptive response. Among these conditions are systemic lupus erythematosus, sarcoidosis, and infections with severe acute respiratory syndrome-coronavirus-2, human immunodeficiency virus, hepatitis C virus, and Mycobacterium tuberculosis.

Utility of 18F-Fluorodeoxyglucose Positron Emission Tomography in Evaluating Disseminated Nontuberculous Mycobacterial Infection in Patients With Anti-interferon-γ Autoantibodies

Background

Managing disseminated nontuberculous mycobacterial (NTM) infection in patients with neutralizing anti-interferon-γ autoantibodies (AIGAs) poses substantial challenges due to the lack of established treatment guidance and predictive tools for clinical outcomes. In this study, we investigated the utility of 18F-fluorodeoxyglucose (2-[18F]FDG) positron emission tomography (PET) in guiding treatment decisions, with a focus on its ability to predict rehospitalization outcomes.

Methods

We conducted a post hoc analysis of the first available 2-[18F]FDG PET scans of patients with AIGAs and disseminated NTM infection from a prospective observational multicenter cohort. Cox proportional hazards regression was used to determine predictors for disease-related rehospitalization within 1 year of the examination.

Results

Of the patients with AIGAs evaluated, 41.9% required rehospitalization within 1 year following the initial 2-[18F]FDG PET evaluation. Slowly growing mycobacteria were isolated in 64.5% of patients. Multivariable analysis identified splenic involvement (adjusted hazard ratio, 7.97; 95% CI, 2.34-27.16; P < .001) as a significant predictor of disease-related rehospitalization within 1 year following the examination. Moreover, mediastinal node involvement (adjusted odds ratio, 14.77; 95% CI, 1.01-216.76; P = .049) and axial skeleton involvement (adjusted odds ratio, 14.93; 95% CI, 1.11-201.43; P = .042) were significantly associated with the isolation of slowly growing mycobacteria.

Conclusions

2-[18F]FDG PET appears useful in initial evaluation of disease extent and microbiology in patients with AIGAs and disseminated NTM infection. Identifying splenic involvement through this modality may help recognize patients at increased risk of disease-related rehospitalization within 1 year. These findings suggest that 2-[18F]FDG PET could inform management decisions in this challenging population.

Multiple pathogen infections accompanied with ocular pathologies in a patient with high-titer Anti-IFN-γ autoantibodies: a case report

The typical clinical characteristic of patients with anti-IFN-γ autoantibodies (AIGAs) is primarily associated with infection caused by intracellular pathogens. With continued research, additional clinical characteristics have been gradually uncovered. Here, we present a case of multiple pathogen infections accompanied by ocular pathologies in a patient with high titers of AIGAs. The patient, a 53-year-old female patient, was admitted to our hospital after finding a mass in the right supraclavicular fossa. She was successively diagnosed with Talaromyces marneffei, Aspergillus flavus and Nontuberculous mycobacteria (NTM) infections. Then, she received a complete course of antifungal agents for nearly 3.5 years and anti-NTM treatment for nearly 3 years, with discontinuation upon symptom improvement. However, there was a rapid recurrence of the infection upon cessation of the drug despite improvement in the patient's symptoms. Moreover, when the recurrent infection stabilized, the patient exhibited immune conjunctivitis and dry eye, which was successfully treated by tacrolimus eye drops and lubricant. Patients with high-titer AIGAs are more prone to experiencing recurrence and/or persistent infection, as well as immune disorders.

Targeting cytokine networks in neuroinflammatory diseases

In neuroinflammatory diseases, systemic (blood-borne) leukocytes invade the central nervous system (CNS) and lead to tissue damage. A causal relationship between neuroinflammatory diseases and dysregulated cytokine networks is well established across several preclinical models. Cytokine dysregulation is also observed as an inadvertent effect of cancer immunotherapy, where it often leads to neuroinflammation. Neuroinflammatory diseases can be separated into those in which a pathogen is at the centre of the immune response and those of largely unknown aetiology. Here, we discuss the pathophysiology, cytokine networks and therapeutic landscape of 'sterile' neuroinflammatory diseases such as multiple sclerosis (MS), neuromyelitis optica spectrum disorder (NMOSD), neurosarcoidosis and immune effector cell-associated neurotoxicity syndrome (ICANS) triggered by cancer immunotherapy. Despite successes in targeting cytokine networks in preclinical models of neuroinflammation, the clinical translation of targeting cytokines and their receptors has shown mixed and often paradoxical responses.

Advances in the understanding of talaromycosis in HIV-negative patients (especially in children and patients with hematological malignancies): A comprehensive review

Talaromyces marneffei (T. marneffei) stands out as the sole thermobiphasic fungus pathogenic to mammals, including humans, within the fungal community encompassing Ascomycota, Eurotium, Eurotiumles, Fungiaceae, and Cyanobacteria. Thriving as a saprophytic fungus in its natural habitat, it transitions into a pathogenic yeast phase at the mammalian physiological temperature of 37°C. Historically, talaromycosis has been predominantly associated with human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS), classified among the three primary opportunistic infections linked with AIDS, alongside tuberculosis and cryptococcosis. As advancements are made in HIV/AIDS treatment and control measures, the incidence of talaromycosis co-infection with HIV is declining annually, whereas the population of non-HIV-infected talaromycosis patients is steadily increasing. These patients exhibit diverse risk factors such as various types of immunodeficiency, malignant tumors, autoimmune diseases, and organ transplantation, among others. Yet, a limited number of retrospective studies have centered on the clinical characteristics and risk factors of HIV-negative talaromycosis patients, especially in children and patients with hematological malignancies, resulting in an inadequate understanding of this patient cohort. Consequently, we conducted a comprehensive review encompassing the epidemiology, pathogenesis, risk factors, clinical manifestations, diagnosis, treatment, and prognosis of HIV-negative talaromycosis patients, concluding with a prospectus of the disease's frontier research direction. The aim is to enhance comprehension, leading to advancements in the diagnosis and treatment rates for these patients, ultimately improving their prognosis.

The ouroboros of autoimmunity

Human autoimmunity against elements conferring protective immunity can be symbolized by the 'ouroboros', a snake eating its own tail. Underlying infection is autoimmunity against three immunological targets: neutrophils, complement and cytokines. Autoantibodies against neutrophils can cause peripheral neutropenia underlying mild pyogenic bacterial infections. The pathogenic contribution of autoantibodies against molecules of the complement system is often unclear, but autoantibodies specific for C3 convertase can enhance its activity, lowering complement levels and underlying severe bacterial infections. Autoantibodies neutralizing granulocyte-macrophage colony-stimulating factor impair alveolar macrophages, thereby underlying pulmonary proteinosis and airborne infections, type I interferon viral diseases, type II interferon intra-macrophagic infections, interleukin-6 pyogenic bacterial diseases and interleukin-17A/F mucocutaneous candidiasis. Each of these five cytokine autoantibodies underlies a specific range of infectious diseases, phenocopying infections that occur in patients with the corresponding inborn errors. In this Review, we analyze this ouroboros of immunity against immunity and posit that it should be considered as a factor in patients with unexplained infection.

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.

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.

A rare presentation of Legionella pneumophila and Mycobacterium intracellulare co-infection masquerading as metastatic lung cancer in a patient with positive anti-interferon gamma antibody

Adult-onset immunodeficiency (AOID) syndrome due to the presence of anti-interferon gamma antibody (AIGA) is characterized by multiple opportunistic infections. We report a case of a 65-year old healthy woman who suffered from Legionella pneumophila and Mycobacterium intracellulare co-infection with clinical presentation mimicking metastatic lung cancer. She presented with chronic cough and weight loss. Her positron emission tomography scan showed a right upper lobe mass, mediastinal lymphadenopathy and multiple bone lesions. Acid fast bacilli culture of the lung mass and mediastinal lymph node revealed Mycobacterium intracellulare and she improved with prolonged antibiotic. Relapse of disseminated Mycobacterium intracellulare infection occurred 15 months post-treatment and AIGA was positive with functional neutralizing activity on downstream immune pathway. AOID syndrome secondary to AIGA was diagnosed. This case illustrated the importance of high index of suspicion of AOID syndrome and the difficulty of early diagnosis. Further studies on its predictive factors and AIGA-targeted treatment modalities are urgently needed.

Brain Nocardiosis and Pulmonary Talaromycosis Infection in a Patient with Anti-IFN-γ Autoantibodies: A Case Report

Adult-onset acquired immunodeficiency caused by anti-IFN-γ autoantibodies is associated with severe opportunistic infection. Due to lack of specific symptoms and different manifestations, this form of infection can be easily misdiagnosed or overlooked. Herein, we present a case of Nocardia farcinica and Talaromyces marneffei co-infection in a patient with anti-IFN-γ autoantibodies (AIGAs). The patient, a 54-year-old man, presented with a 1-month history of fever, coughing and expectoration, dizziness, headache and gait imbalance. Laboratory workup revealed increased inflammatory markers, negative anti-HIV antibody and a high positive titer of AIGAs. Chest computed tomography (CT) showed multiple patches of high-density shadows in both lungs, and brain enhanced magnetic resonance imaging (MRI) showed an irregular lesion. The patient underwent a craniotomy for resection of the lesion. Pulmonary T. marneffei infection was diagnosed through sputum and bronchoalveolar lavage fluid culture, and brain nocardiosis was confirmed via purulent fluid culture of brain tissue. With regular antibiotic therapy, his symptoms improved and there was no recurrence during 18-month follow-up. This may be the first detailed case report detailing infection with these two distinct pathogens in disparate anatomical locations.

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.

Of Mycelium and Men: Inherent Human Susceptibility to Fungal Diseases

In medical mycology, the main context of disease is iatrogenic-based disease. However, historically, and occasionally, even today, fungal diseases affect humans with no obvious risk factors, sometimes in a spectacular fashion. The field of “inborn errors of immunity” (IEI) has deduced at least some of these previously enigmatic cases; accordingly, the discovery of single-gene disorders with penetrant clinical effects and their immunologic dissection have provided a framework with which to understand some of the key pathways mediating human susceptibility to mycoses. By extension, they have also enabled the identification of naturally occurring auto-antibodies to cytokines that phenocopy such susceptibility. This review provides a comprehensive update of IEI and autoantibodies that inherently predispose humans to various fungal diseases.