Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Persistently abnormal liver function tests: Marker of occult hepatitis C?

05.01.2004


Patients with persistently abnormal liver function tests but no serologic evidence of liver disease may nevertheless have hepatitis C virus (HCV) infection, according to a study published in the January 1 issue of The Journal of Infectious Diseases, available online now.



Such occult (meaning hidden or concealed) infection is not supposed to occur--the conventional wisdom is that the virus leaves markers in serum or plasma, including specific antibodies and viral RNA, which have been the serologic cornerstones for diagnosing and monitoring HCV-infected patients. Although occult HCV infection generally appears to be mild, some patients have shown evidence of serious chronic liver injury. In addition, occult infection raises the possibility of disease spread via blood donations, hemodialysis and other procedures. Fortunately, the study also suggests a minimally invasive approach to detect occult infection.

The study, reported by a group headed by Vicente Carreño, MD, in Madrid, Spain, involved 100 patients with abnormally high levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT) or gamma glutamyl transpeptidase (GGTP) for at least 12 months in whom all causes of liver disease, including HCV infection, had ostensibly been excluded. All three liver enzymes were elevated in eight patients, two of the enzymes in 48 and one enzyme in 44. For comparison, 30 patients with liver damage known to be of non-viral origin were also studied.


The investigators relied on two assays to demonstrate the presence or absence of HCV infection. First, using reverse transcription-polymerase chain reaction (RT-PCR) with primers from one region of the HCV genome, they detected the virus’s RNA in liver biopsies from 57 (57%) of the patients with abnormal liver enzymes of unknown etiology, compared to none of the biopsies from control patients. When primers from another region of the genome were used in the RT-PCR assay, HCV RNA was found in liver biopsies from 40 (70%) of the 57 patients. The second method used was in situ hybridization, which demonstrated positive-strand HCV RNA in liver biopsies from the same 57 patients, but in none of those from the controls, and negative-strand HCV RNA in 48 (84%). The investigators noted that the latter finding suggested viral replication, which involves synthesis of a negative RNA intermediary.

The RT-PCR assay also detected HCV RNA in peripheral-blood mononuclear cells from 40 (70%) of the 57 patients with occult infection. The clinical implication of this finding, the investigators noted, is that a high percentage of patients with occult HCV infection may be more easily and more safely identified by obtaining and testing blood cells rather than liver cells.

In an accompanying editorial, Hervé Lerat, MD, and F. Blaine Hollinger, MD, of Baylor College of Medicine, Houston, commented that the distribution of hepatic enzyme elevations in the study population implied that clinicians should use both ALT and GGT to identify patients who may qualify for peripheral-blood mononuclear cell testing for occult HCV infection. They cautioned, however, that many issues about such infections remain to be resolved, including the central issue of whether the detected viral genomic material is infectious.


Founded in 1904, The Journal of Infectious Diseases (JID) is the premier publication in the Western Hemisphere for original research on the pathogenesis, diagnosis and treatment of infectious diseases; on the microbes that cause them; and on disorders of host immune mechanisms. Articles in JID include research results from microbiology, immunology, epidemiology and related disciplines. JID is published under the auspices of the Infectious Diseases Society of America (IDSA), based in Alexandria, Va., a professional society representing more than 7,000 physicians and scientists who specialize in infectious diseases.

Note: Interviews with Drs. Carreño and Hollinger can be arranged by contacting Diana Olson at dolson@idsociety.org or 703-299-0201.

Diana Olson | EurekAlert!
Further information:
http://www.idsociety.org/

More articles from Health and Medicine:

nachricht Norovirus evades immune system by hiding out in rare gut cells
12.10.2017 | University of Pennsylvania School of Medicine

nachricht Flexible sensors can detect movement in GI tract
11.10.2017 | Massachusetts Institute of Technology

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: Neutron star merger directly observed for the first time

University of Maryland researchers contribute to historic detection of gravitational waves and light created by event

On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...

Im Focus: Breaking: the first light from two neutron stars merging

Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.

Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....

Im Focus: Smart sensors for efficient processes

Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).

When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...

Im Focus: Cold molecules on collision course

Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.

How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...

Im Focus: Shrinking the proton again!

Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.

It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ASEAN Member States discuss the future role of renewable energy

17.10.2017 | Event News

World Health Summit 2017: International experts set the course for the future of Global Health

10.10.2017 | Event News

Climate Engineering Conference 2017 Opens in Berlin

10.10.2017 | Event News

 
Latest News

Ocean atmosphere rife with microbes

17.10.2017 | Life Sciences

Neutrons observe vitamin B6-dependent enzyme activity useful for drug development

17.10.2017 | Life Sciences

NASA finds newly formed tropical storm lan over open waters

17.10.2017 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>