Table 1 -Indications of bronchoscopy of all patients (n=707).
Handheld Test Improves TB Detection In HIV Patients
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A portable diagnostic device that uses a beetle-inspired chemical reaction has shown improved detection of tuberculosis (TB) in individuals with HIV, according to research published in Nature Biomedical Engineering. The test, called the Antigen-Specific T-cell Response Assay (ASTRA), aims to address diagnostic limitations of existing TB tests, particularly in populations with high HIV prevalence.
Diagnostic challenge in HIV co-infectionMore than 90% of the estimated 2 billion TB cases globally are latent, meaning they show no symptoms and are not contagious. In individuals with HIV, however, immune suppression can allow latent TB to become active, increasing disease transmission and mortality. TB is the leading cause of death among HIV-positive individuals.
Traditional TB tests such as the Interferon-Gamma Release Assay (IGRA) depend on immune cell responses that HIV can suppress, reducing test accuracy. This diagnostic gap poses a significant challenge for public health efforts in regions with high HIV incidence.
A new approach to TB testingThe ASTRA test was developed by researchers at Tulane University. Roughly the size of a credit card, the device is designed for low-resource settings. It requires just a drop of blood and does not need laboratory facilities or electricity to operate.
In comparative testing, ASTRA showed 87% specificity in detecting TB among HIV-positive individuals, significantly outperforming the 60% specificity of the IGRA. The device also performed well in HIV-negative individuals. Results are available in about four hours, offering a faster alternative to the 24-hour turnaround time of the IGRA and the two to three days required for the TB skin test.
Beetle-inspired mechanicsThe ASTRA test incorporates a unique mechanism modeled after the bombardier beetle, which uses a chemical reaction to produce a defensive spray. The device mimics this process by combining two chemicals to propel the blood sample across a microfluidic chip. This enables the analysis without the need for powered components.
The test works by introducing a reagent that prompts immune cells to react if they recognize Mycobacterium tuberculosis, the bacterium that causes TB. Crucially, the method relies on two newly identified biomarkers that allow detection even when HIV has compromised the typical immune cell response.
Field validationTo evaluate the device's effectiveness, researchers tested it on samples from a cohort in Eswatini, a country with one of the highest TB and HIV burdens globally. Eswatini has an HIV prevalence rate of 27.3%, making it a critical setting for assessing the utility of improved TB diagnostics.
As TB drug resistance becomes more widespread, the need for early and accurate diagnosis is increasingly urgent. Tools like ASTRA that enhance diagnostic capabilities in high-risk populations could play an important role in controlling disease spread.
Reference: Ning B, Chandra S, Pan Y, et al. Self-powered rapid antigen-specific T-cell response assay for Mycobacterium tuberculosis infections. Nat Biomed Eng. 2025. Doi:10.1038/s41551-025-01441-5
This content includes text that has been generated with the assistance of AI. Technology Networks' AI policy can be found here.
More Than Half Of Patients With TB Had No Symptoms Before Testing Positive - Healio
January 13, 2023
2 min read
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Researchers found high rates of tuberculosis among high-risk patients who sought care at primary health care clinics, many of whom had no preceding symptoms suggesting a high rate of subclinical TB.
"WHO estimates that each year, more than 4 million out of the 10 million people with active TB are not diagnosed or started on treatment. Identifying and treating this group is central to the global End TB strategy," Rebecca H. Berhanu, MD, infectious diseases physician and clinical researcher at the Vanderbilt Institute for Global Health, told Healio.
Berhanu RH, et al. Clin Infect Dis. 2022;doi:10.1093/cid/ciac965.
"The objective of this study was to see if we could find people who were asymptomatic or did not have overt symptoms of TB by testing all high-risk people attending primary health care clinics, including people with HIV, those with a close household contact with TB and people with a prior history of treated TB," she said.
Berhanu added that she and colleagues called this strategy "Targeted Universal Testing for TB."
The researchers assessed clinic attendees in primary health care facilities in South Africa who were classified as high risk for TB due to HIV-positive status, contact with a patient with TB in the past year or having TB themselves and having undergone sputum testing for pulmonary TB in the previous 2 years.
According to the study, a single sample was collected for Xpert Ultra and culture and the results were analyzed.
Overall, 30,513 patients had a TB test result available for analysis. Of these, 21,734 (71%) were HIV positive, 12,492 (41%) reported close contact with a person with TB and 1,573 (5%) reported a prior TB diagnosis. In total, 8.3% of these patients were positive for Mycobacterium tuberculosis by culture and/or Xpert, compared with 6% with trace-positive results excluded.
Additionally, and also with trace-positives excluded, the study showed a yield of 6.7% for asymptomatic patients and 10.1% for symptomatic patients, whereas only 10% of trace-positive results were culture positive.
Berhanu added that more than half (55%) of patients with a positive test did not report any preceding TB symptoms, which she said suggests a high rate of subclinical TB among people attending primary health care clinics.
"Universal testing of individuals at high risk for TB in primary health care clinics may be a good way of identifying subclinical TB cases sooner. However, we have to be cautious of the interpretation of Xpert Ultra test results, especially Xpert Ultra-trace positive results, in this population," Berhanu concluded.
Sources/DisclosuresCollapse Disclosures: Berhanu reports receiving support from the NIH. Please see the study for all other authors' relevant financial disclosures.Add topic to email alerts
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HIV And Tuberculosis: Causes, Symptoms, Treatments, And More - Medical News Today
A person with HIV may be more at risk of developing tuberculosis (TB). This is due to the weakening of the immune system that occurs in someone who has HIV.
Tuberculosis (TB) is a bacterial infection that can spread through the air. TB typically affects the lungs, but it can spread to other parts of the body.
HIV is a virus that can spread from person to person through bodily fluids, causing a weakening of the immune system. A weakened immune system may increase the risk of TB infection.
Read on to learn about the link between HIV and TB. This article also looks at symptoms of TB, when an individual with HIV should get a TB test, TB treatments for someone with HIV, and more.
A person can contract TB when they inhale the TB bacterium Mycobacterium tuberculosis. The TB bacteria can then settle in the lungs. It may spread to other parts of the body, including the spine, kidneys, and brain.
When an individual has HIV, the immune system becomes weaker. This can make the body less able to fight off infections and bacteria such as TB.
According to the National Institutes of Health (NIH), TB is an opportunistic infection (OI). This means that it is more common and more severe in people with weakened immune systems.
Therefore, a person with HIV may be more likely to develop TB and have more severe symptoms than a someone without HIV.
According to the World Health Organisation (WHO), an individual with HIV may be 20 times more likely to develop TB. The WHO also reports that TB is the leading cause of death in people with HIV worldwide.
Medications for TB in a person with HIV is typically the same as when someone does not have HIV.
However, there may be factors a healthcare professional has to consider when prescribing TB medication to a person with HIV, as it is possible the two treatments can interact and cause further issues.
TB treatment may also require adjustment depending on whether an individual has already started HIV treatment or has developed any resistance to medications.
The type of medication and the duration of treatment can depend on whether a person has latent TB or active TB, as well as whether they experience medication resistance.
Examples of medications for HIV include:
Treatment can last for a number of months, but this will depend on the specific drugs a doctor recommends. An individual's doctor can provide them with more accurate information about what they can expect from treatment.
As HIV causes a weakened immune system, a person with HIV may be around 20 times more likely to catch TB. TB is also the leading cause of death in people with HIV.
TB symptoms may be more severe in an individual with HIV. Examples of symptoms include a persistent cough, coughing up blood, breathlessness, fever, fatigue, chest pain, and loss of appetite.
Someone with HIV should receive regular testing and screening for TB. If they have latent TB infection or active TB, a doctor will recommend medications. Treatment usually lasts a number of months.
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