An observational study in Nontuberculous Mycobacteria, Mycobacterium Tuberculosis and Opportunistic Infections, sponsored by National Institute of Allergy and Infectious Diseases (NIAID). Active, not recruiting at 5 sites in 3 countries. Open to participants aged 18 Years to 100 Years. Per ClinicalTrials.gov, last updated 2026-10-02.
Sponsored by National Institute of Allergy and Infectious Diseases (NIAID) · Observational
Opportunistic infections are caused by bacteria, mycobacteria, fungi or viruses that do not normally cause infections in people with healthy immune systems. Some of these infections can cause public health concerns, especially in areas with limited access to treatment. People who acquire opportunistic infections usually have diseases that affect their immune systems, such as human immunodeficiency virus (HIV), or do not have enough white blood cells to fight the infection. However, some people acquire opportunistic infections even though they have normal amounts of white blood cells and are free from known diseases that harm their immune systems. This study will investigate some of the reasons that otherwise healthy people get opportunistic infections to learn more about why some people are more likely to have them.
This study will include up to 210 HIV-negative males and females older than 18 years of age who have opportunistic infections. The patients will be drawn from multiple sites in Thailand and Taiwan including Khon Kaen University Hospital, Siriraj Hospital, Ramathibodi Hospital, National Taiwan University Hospital, National Cheng-Kung University Hospital
Patients will undergo an initial evaluation that will include a physical examination, medical history, and blood and urine testing. Additional tests will be conducted if the researchers consider that the tests are medically necessary to treat the opportunistic infection; the results of the tests will be reviewed and saved for study purposes. Depending on the severity of the infection, the initial evaluation may take more than 1 day to complete.
After the evaluation, patients will be given standard and appropriate medicines to treat the infections.
Patients will return for follow-up visits to allow researchers to monitor their condition and to assess how well the patient is responding to the treatment. Patients will be evaluated by the study researchers at least once a year for 2 years following the initial treatment.
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The acquisition of opportunistic infections has been causally linked to innate and acquired immunodeficiencies. We have recently identified a population of Asian women with autoantibodies to interferon gamma (IFNg), all of whom were diagnosed by virtue of nontuberculous mycobacterial infections. Similar patient populations have been reported from Thailand and Taiwan, and we have found similar autoantibodies in anonymous serum samples from there. In addition, many of the patients who have disseminated or lymphatic nontuberculous infections have had other opportunistic infections (OI), such as salmonella, penicilliosis, and histoplasmosis. Recently, patients who are clinically similar to our Thai population were described in Taiwan. Two of these cases have been diagnosed with IFNg autoantibodies (unpublished data). The described patients have normal lymphocyte counts and are human immunodeficiency virus (HIV) negative. Therefore, the identification of autoantibodies to a critical cytokine, the occurrence of opportunistic infections, and the lack of other common explanations suggest that this is an important population to study. We propose to enroll patients in a natural history study of non-HIV opportunistic infections to explore the presence of autoantibodies to cytokines, and to examine potential immunogenetic factors influencing the development of this disease. Plasma, cells, and DNA samples will be obtained and stored for use in this study. This study will accrue up to 265 patients over 5 years as per the protocol with follow up for 20 years on each patient, sample size justification and the groups described in the protocol.
40 studies on the registry are indexed under Opportunistic Infections; 11 are open to participants now.
This study's enrollment of 224 is below the median of 589 across 16 observational studies indexed under Opportunistic Infections.
Browse Opportunistic Infections studies →National Institute of Allergy and Infectious Diseases (NIAID) is the lead sponsor of 2,401 studies on the registry; 179 are open to participants now.
Of its 396 completed or terminated interventional studies of FDA-regulated products, 294 (74%) have results posted.
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This is a prospective natural history cohort study with a case-control component. Patients will be recruited from 5 groups: 1) subjects with NTM alone, 2) subjects with a non-NTM OI, either with or without concurrent NTM infection, 3) subjects with pulmonary MTB, 4) subjects with disseminated MTB, and 5) Blood Specimen Donor controls.
Patients must meet all of the following criteria at the time of evaluation to be eligible for enrollment into the study cohorts:
Group 1 (NTM alone):
Group 2 (non-NTM OI with or without NTM):
Group 3 (diseased control with pulmonary MTB):
Group 4 (diseased control with disseminated MTB):
Disseminated MTB includes infections involving greater than or equal to 2 noncontiguous sites, one of which may include pulmonary disease or greater than or equal to 2 separate groups of lymph nodes.
Group 5 (Blood Specimen Donor):
Eligibility criteria not applicable. Blood will be collected from volunteers, and no medical evaluation will be performed.
To be a blood donor the person cannot be excluded per these exclusionary criteria: Patient cannot be less that 18 or more than 85, Patient must not weigh less than 45 KG (99 Lbs), Patient cannot be receiving chemotherapy or have cancer, Patient cannot be receiving any immunosuppressant medications, Patient cannot have a history of heart, lung, kidney disease or bleeding disorder.
Samples will be collected from anyone of the collaborating sites. Immediately after drawing a specimen it will be assigned a number that is unlinked to the person donating. Thus, they will be anonymous and not traceable back to the original volunteer. Subjects will be consented and compensated for their contribution.
EXCLUSION CRITERIA:
Patients will be excluded for the following reasons:
Patients with nontuberculous mycobacteria (NTM) alone.
Patients with non-NTM opportunistic infection, either with or without concurrent NTM infection.
Patients with pulmonary mycobacterium tuberculosis (MTB).
Patients with disseminated mycobacterium tuberculosis (MTB).
Blood Specimen Donors.
Identification of the presence of autoantibodies to IFNy in HIV-negative Thai and Taiwanese patients with disseminated NTM and OI who are followed at the participating institutions.
Compare the baseline prevalence rate of autoantibodies to IFNg, as defined by having \>75% inhibition, in patients with disseminated NTM or other OI (groups 1 and 2) versus normal or diseased controls (groups 3 and 5).
Time frame: ongoing
Identification of predisposing factors for the development of autoimmunity to cytokines and/or their receptors.
Identification of predisposing factors for the development of autoimmunity to cytokines and/or their receptors.
Time frame: ongoing
Identification of other autoantibodies that might manifest similarly to patients with autoantibodies to IFNg.
Identification of other autoantibodies.
Time frame: ongoing
Characterization of the natural history and specific microbiology in HIV-negative patients with disseminated NTM and other OI and to determine any statistically significant differences from MTB controls or healthy blood bank donors.
Characterization of the natural history and infections of consecutive patients with NTM alone and NTM with other OI. Speciation of the opportunistic infections identified and categorization of these infections with descriptive statistics.
Time frame: ongoing
Plan to share: Yes — We will share human data generated in this study for future research as follows:@@@@@@@@@@@@ (Summation)Identified data in the Biomedical Translational Research Information System (BTRIS, automatic for activities in the NIH CC).@@@@@@@@@@@@ (Summation)De-identified or identified data with approved outside collaborators under appropriate agreements.@@@@@@@@@@@@ (Summation)Data sharing may be complicated or limited in certain cases by contractual obligations or agreements with outside collaborators, such as cooperative research and development agreements, clinical trial agreements, other restraints, etc.
Supporting information: Sap
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
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National Institute of Allergy and Infectious Diseases (NIAID)