Medical Bulletin 23/June/2023

Here are the top medical news for the day:

A promising device offers hope for tuberculosis diagnosis in the "missing millions"

In a recent cutting-edge study, scientists test a diagnostic device using dielectrophoresis that holds promise for improving TB detection and treatment of patients in high-endemic, under-resourced areas.

The investigators describe a prototype microfluidic lab-on-a-chip system called CAPTURE-XT® from QuantuMDx that can process solubilized sputum from suspected TB patients, capture Mtb bacilli for visual analysis (as a substitute for smear microscopy), and provide a purified sample for molecular confirmation by quantitative PCR (qPCR) and ultimately for genotypic drug-susceptibility analysis. CAPTURE-XT® technology relies on the principle of dielectrophoresis – a little-utilized technique that can be tuned to selectively attract or repel specific particles or cells based on their dielectric properties. In this case, it is the Mtb bacteria that cause TB that are specifically captured and concentrated, while the other sputum contents are washed away.

Reference: “A Novel Microfluidic Dielectrophoresis Technology to Enable Rapid Diagnosis of Mycobacteria Tuberculosis in Clinical Samples,” by Catherine M. Moore, Jasvir Dhillon, Rebecca Flynn, Krzysztof Gizynski, Candice Adams, George Morgan, David McGurk, Eduardo Boada, Shireen Shabestary, Jonathan Peat, Jonathan O’Halloran, Neil G. Stoker, Philip D. Butcher, and Heather Murton (https://doi.org/10.1016/j.jmoldx.2023.04.005). It appears in The Journal of Molecular Diagnostics

A novel diagnostic tool for detecting cancer

A team led by researchers at Harvard Medical School has developed a new tool that promises to improve the way pathologists see and evaluate a tumor by providing detailed clues about cancer. The tool, called Orion, combines histologic with molecular information and offers deeper insight into a tumor’s type, behavior, and likely response to treatment.

Orion consists of a powerful digital imaging platform that integrates information gained through traditional histology with details revealed by molecular imaging on a tumor sample.

The researchers used Orion on tumor samples from 74 patients with colorectal cancer organized into two groups. They found that the information provided by the tool allowed them to identify a biomarker of outcome or a specific combination of features that predicted which colorectal cancers were likely to progress and which were not.

Reference: Multi-modal digital pathology for colorectal cancer diagnosis by high-plex immunofluorescence imaging and traditional histology of the same tissue section, Nature Cancer, DOI 10.1038/s43018-023-00576-1

New research brings into question the current understanding of genetic factors behind early menopause 

The genetic causes of very early menopause will have to be reconsidered after researchers found that nearly all women who carried variations thought to cause the condition in fact had their menopause at an older age.

Until now, variants in any one of more than 100 genes were thought to cause premature ovarian insufficiency (POI), which results in menopause before the age of 40 and affects around one per cent of women, making it a leading cause of infertility. Under current guidance, a variation in one of these genes is cause for clinicians to consider a genetic diagnosis of POI.

Now, in the largest study to date, published in Nature Medicine, a team led by the University of Exeter and the University of Cambridge analyzed genetic data from more than 104,733 women in UK Biobank, of whom 2,231 reported experiencing menopause before the age of 40.

Reference: Penetrance of pathogenic genetic variants associated with Premature Ovarian Insufficiency, Nature Medicine, DOI 10.1038/s41591-023-02405-5