New Lyme disease test distinguishes between early and late-stage disease

  • New test targets genetic sequences in Lyme-causing bacteria and is highly sensitive, detecting just one bacterial cell in a blood sample

 

(April 7, 2021) — For those who live in an area blighted by ticks, the threat of Lyme disease can cast a shadow over the joy of spring and summer. These blood-sucking arachnids can transmit bacteria into the bloodstream of their unsuspecting host, causing the disease. Early treatment is essential, but current tests are not usually sensitive enough to detect the disease in early-stage patients. A recent study in open-access journal Frontiers in Microbiology reveals a new test for Lyme disease, which is the first to reliably distinguish between early- and late-stage patients. The test detects a genetic sequence left by a virus that resides in Lyme-causing bacteria, and can detect just one bacterial cell in a small blood sample.

As the most common tick-borne infection, Lyme disease affects nearly 500,000 people in the U.S. every year. Symptoms include fever, fatigue, joint pain, and a distinctive ‘bullseye’ rash, but if left untreated, the disease can cause paralysis and even death. As such, early diagnosis is important, but difficult.

“Early diagnosis of Lyme disease is absolutely vital in reducing suffering, because early Lyme can be treated, but late Lyme is very difficult to treat,” explained Dr Jinyu Shan of the University of Leicester, lead author on the study. “Current tests cannot typically detect the low numbers of bacteria in early-stage patient blood samples. Our goal was to design a highly sensitive test to help doctors to identify Lyme disease as early as possible.”

Shan’s test is based on polymerase chain reaction, or PCR, which works by amplifying small amounts of specific genetic material so that it can be detected. To date, this technique has not been particularly useful in detecting Lyme-causing bacteria in the blood. Such bacteria often lurk in tissues, and may not be present in the blood in large numbers. Additionally, many of the genetic sequences targeted by PCR have only a single copy within each cell, making it difficult to find and amplify enough for detection.

Shan and his colleagues realized that there is another potential PCR target in Lyme-causing bacteria. These targets are called prophages, and are a genetic sequence that was inserted into the bacteria by a virus. Happily, such genetic material can escape the bacteria and is therefore more likely to be detectable in the blood, and multiple copies are present in individual bacterial cells.

The researchers assessed their new prophage-targeted test by adding small amounts of Lyme-causing bacteria to blood samples. They found that the test was very sensitive, detecting just one bacterial cell in 0.3 mL of blood. This suggests that the test is sensitive enough for use with human samples, as people infected with Lyme-causing bacteria typically have between 1 and 100 bacterial cells per mL of blood.

Based on these promising results, the researchers used their PCR test to analyze blood samples from healthy volunteers and patients with either early-stage or late-stage Lyme disease. Strikingly, the test could successfully distinguish healthy, early-stage and late-stage Lyme disease samples, and is the first technology to successfully achieve this. “The test could also be very useful in rapidly ruling out someone with suspected Lyme disease,” said Shan.

The technique may also be applicable to diagnostic tests for other bacterial infections, if researchers can identify suitable prophage sequences for such bacteria. The technology will need further development before it is suitable for clinical use, but the researchers have already begun the groundwork for this. “We are currently working with a commercial partner, and investigating regulatory issues and the potential for a clinical trial for this technology,” said Shan.

 

 


Frontiers in Microbiology, 07.04.2021 (tB).

Schlagwörter: ,

MEDICAL NEWS

Inadequate sequencing of SARS-CoV-2 variants impedes global response to COVID-19
New meta-analysis finds cannabis may be linked to development of…
New guidance on how to diagnosis and manage osteoporosis in…
Starting the day off with chocolate could have unexpected benefits
Better mental health supports for nurses needed, study finds

SCHMERZ PAINCARE

Versorgung verbessern: Deutsche Gesellschaft für Schmerzmedizin fordert die Einführung des…
Pflegeexpertise im Fokus: Schmerzmanagement nach Operationen
Versorgung verbessern: Bundesweite Initiative der Deutschen Gesellschaft für Schmerzmedizin zu…
Jedes vierte Kind wünscht bessere Schmerzbehandlung
Lebensqualität von Patienten in der dauerhaften Schmerztherapie mit Opioiden verbessern

DIABETES

„Wissen was bei Diabetes zählt: Gesünder unter 7 PLUS“ gibt…
Toujeo® bei Typ-1-Diabetes: Weniger schwere Hypoglykämien und weniger Ketoazidosen 
Bundestag berät über DMP Adipositas: DDG begrüßt dies als Teil…
Mit der Smartwatch Insulinbildung steuern
Verbände fordern bessere Ausbildung und Honorierung von Pflegekräften für Menschen…

ERNÄHRUNG

Wie eine Diät die Darmflora beeinflusst: Krankenhauskeim spielt wichtige Rolle…
DGEM plädiert für Screening und frühzeitige Aufbautherapie: Stationäre COVID-19-Patienten oft…
Führt eine vegane Ernährungsweise zu einer geringeren Knochengesundheit?
Regelmässiger Koffeinkonsum verändert Hirnstrukturen
Corona-Erkrankung: Fehl- und Mangelernährung sind unterschätze Risikofaktoren

ONKOLOGIE

Anti-Myelom-Therapie mit zusätzlich Daratumumab noch effektiver
Positive Ergebnisse beim fortgeschrittenen Prostatakarzinom: Phase-III-Studie zur Radioligandentherapie mit 177Lu-PSMA-617
Lymphom-News vom EHA2021 Virtual. Alle Berichte sind nun online verfügbar!
Deutsch-dänisches Interreg-Projekt: Grenzübergreifende Fortbildungskurse in der onkologischen Pflege
Sotorasib: Neues Medikament macht Lungenkrebs-Patienten Hoffnung

MULTIPLE SKLEROSE

NMOSD-Erkrankungen: Zulassung von Satralizumab zur Behandlung von Jugendlichen und Erwachsenen
Verzögerte Verfügbarkeit von Ofatumumab (Kesimpta®)
Neuer Biomarker bei Multipler Sklerose ermöglicht frühe Risikoeinschätzung und gezielte…
Multiple Sklerose beginnt oft lange vor der Diagnose
Goldstandard für Versorgung bei Multipler Sklerose

PARKINSON

Meilenstein in der Parkinson-Frühdiagnose
Parkinson-Erkrankte besonders stark von Covid-19 betroffen
Gangstörungen durch Kleinhirnschädigung beim atypischen Parkinson-Syndrom
Parkinson-Agenda 2030: Die kommenden 10 Jahre sind für die therapeutische…
Gemeinsam gegen Parkinson: bessere Therapie durch multidisziplinäre Versorgung