Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Tiny tool can play big role against tuberculosis, UF researcher finds

18.05.2012
A tiny filter could have a big impact around the world in the fight against tuberculosis. Using the traditional microscope-based diagnosis method as a starting point, a University of Florida lung disease specialist and colleagues in Brazil have devised a way to detect more cases of the bacterial infection.

"We're hopeful that this more sensitive method, which is both simple and inexpensive, will improve diagnosis in patients," said lead researcher Kevin Fennelly, M.D., M.P.H., an associate professor in the UF College of Medicine's department of medicine and Southeastern Tuberculosis Center, and the UF Emerging Pathogens Institute.

The new technique, which involves vacuum filtering a sputum sample treated with household bleach and other simple chemicals through a small filter, could dramatically improve TB diagnoses globally, particularly in settings where the disease is common and resources are limited. It is especially useful when the presence of only a small number of bacteria in the test sample makes it hard to detect TB. The researchers are refining the technique in hopes of developing a cost-effective product that can be used globally.

Funded by the World Health Organization and the Núcleo de Doenças Infecciosas infectious disease institute in Brazil, the study appears online and in an upcoming print edition of the Journal of Clinical Microbiology.

TB is a treatable disease caused by a microbe called Myocardium tuberculosis. It most often affects the lungs, but can also target organs such as the brain, spine and kidneys. Symptoms of active disease include a chronic cough, sputum production and coughing up blood. TB spreads from person to person through the air.

Once the leading cause of death in the U.S., TB has been largely under control in Western nations. Still, more than 11,000 U.S. cases were reported in 2010, the latest year for which there is comprehensive data. That year, almost 9 million people around the world were diagnosed with TB and almost 1.5 million died from it. TB causes more deaths than any other bacterial infection and is the most common killer of people living with HIV.

"TB is still a tremendously important disease worldwide and control efforts are greatly hindered by lack of simple, inexpensive diagnostics that could be used at the point of care," said Elizabeth Talbot, M.D., a Dartmouth College infectious diseases and TB diagnostics expert who was not involved in the UF research. "What Dr. Fennelly has done is capitalize on existing infrastructure of microscopy to try to improve performance of that prevalent diagnostic tool."

The most widely used way to confirm TB infection is to use a microscope to identify and count disease-causing bacteria in sputum smeared onto a glass slide. This so-called direct-smear method also helps health professionals figure out how likely people are to pass on the disease, what treatment decisions should be made, and how well patients are responding to treatment. Although the method has been in continuous use for more than a century, it can be unreliable, catching cases only about half of the time, on average.

Part of the problem is that sometimes sputum samples don't contain many bacteria, making it hard to detect TB. Concentrating bacteria onto a small area could help improve detection accuracy, and although previous efforts have led to improvements, they tend to require expensive equipment or technical know-how. In some cases, gains were offset by loss of sample or safety concerns. So the quest for a low-cost, simple, effective method led back to the trusty microscope.

In the early 1980s researchers vacuum-filtered sputum samples to trap TB bacteria onto quarter-sized filters that were then viewed under a microscope. But the filters hung over the sides of standard microscope slides, posing a health hazard and preventing proper inspection. So Fennelly and his team decided to try smaller-than-a-dime filters that fit neatly onto microscope slides and that concentrated the bacteria even more.

Among 314 patients in Brazil suspected as having TB, but not yet in treatment, the small-filter method detected 89 percent of cases, compared with 60 percent detection when samples were concentrated by the currently used method of rapid spinning, and 56 percent detection when sputum smears were looked at directly under the microscope. Furthermore, the small-filter method identified almost three-quarters of TB-positive cases that had been incorrectly reported as negative based on the traditional technique.

Fennelly and collaborators are now teaming with the humanitarian organization Médecins Sans Frontières, translated as "Doctors Without Borders," to test the method in western Uganda, where many people have both TB and HIV. They're comparing it again with the traditional direct-smear method and with a sophisticated DNA-based test that can also detect whether bacteria are drug resistant.

Both types of technique have their place — high-tech tools would be most feasible in referral centers, but on the front lines, the small-filter microscope method can perform an invaluable service, the researchers say.

"A point-of-care dipstick that can say yes or no is the Holy Grail, but we're a long way from there," Fennelly said. "'Microscope' has become a dirty word in the TB diagnostics world — but almost every clinical laboratory in the world has one."

Czerne M. Reid | EurekAlert!
Further information:
http://www.ufl.edu

More articles from Health and Medicine:

nachricht NTU scientists build new ultrasound device using 3-D printing technology
07.12.2016 | Nanyang Technological University

nachricht How to turn white fat brown
07.12.2016 | University of Pennsylvania School of Medicine

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Significantly more productivity in USP lasers

In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.

Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...

Im Focus: Shape matters when light meets atom

Mapping the interaction of a single atom with a single photon may inform design of quantum devices

Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

NTU scientists build new ultrasound device using 3-D printing technology

07.12.2016 | Health and Medicine

The balancing act: An enzyme that links endocytosis to membrane recycling

07.12.2016 | Life Sciences

How to turn white fat brown

07.12.2016 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>