We use cookies to understand how you use our site and to improve your experience. This includes personalizing content and advertising. To learn more, click here. By continuing to use our site, you accept our use of cookies. Cookie Policy.

LabMedica

Download Mobile App
Recent News Expo Clinical Chem. Molecular Diagnostics Hematology Immunology Microbiology Pathology Technology Industry Focus

Serum Test Detects Bacterial Infection in Autoimmune Diseases

By LabMedica International staff writers
Posted on 19 Jun 2012
Print article
The serum procalcitonin test (PCT) has been used to detect bacterial infection in patients with autoimmune diseases.

The clinical manifestations of disease flare and infection overlap and are identified by similar laboratory markers so there is an urgent need for a reliable biomarker that discriminates early infection from disease flare in febrile patients with autoimmune disease (AD).

Scientists from Chang Gung University (Tao Yuan, Taiwan) have reviewed studies carried out between January 1966 and October 2011 that had evaluated PCT as a diagnostic marker for bacterial infection in patients with AD, which included nine studies for PCT and five studies for C-reactive protein (CRP).

In healthy individuals, serum PCT is normally undetectable below 0.05 ng/mL, but the level increases rapidly after bacterial infection. In contrast to CRP, PCT does not rise with noninfectious inflammation or nonbacterial infections, making it a potentially useful marker to distinguish bacterial infection from disease flare in the setting of autoimmune disease.

The positive likelihood ratio for PCT was sufficiently high to be qualified as a rule-in diagnostic tool, while the negative likelihood ratio was not sufficiently low to be qualified as a reliable rule-out diagnostic tool. The area under the receiver-operating curve was higher for PCT than for CRP. Both markers had suboptimal negative likelihood ratios and so are not suitable tests for excluding bacterial infection in febrile patients with autoimmune diseases.

The authors conclude that different cut off levels are needed to optimize the discriminative capability of PCT for different autoimmune diseases. However, this requires a large study or studies of patients with the same autoimmune disease.

Until the results of such studies are available, they recommend using a standard PCT cut off value of 0.5 ng/mL, which has reasonable sensitivity of 76% and specificity of 88%.

Shy-Shin Chang, MD, lead author of the study said, "Analysis of the pooled data suggests that PCT is a more specific indicator of bacterial infection than CRP, but that CRP is a more sensitive indicator of bacterial infection than PCT." The study was published online on May 17, 2012, in the journal Arthritis and Rheumatism.

Related Links:
Chang Gung University


Platinum Member
COVID-19 Rapid Test
OSOM COVID-19 Antigen Rapid Test
Magnetic Bead Separation Modules
MAG and HEATMAG
Complement 3 (C3) Test
GPP-100 C3 Kit
New
Gold Member
Magnetic Bead Separation Modules
MAG and HEATMAG

Print article

Channels

Hematology

view channel
Image: The CAPILLARYS 3 DBS devices have received U.S. FDA 510(k) clearance (Photo courtesy of Sebia)

Next Generation Instrument Screens for Hemoglobin Disorders in Newborns

Hemoglobinopathies, the most widespread inherited conditions globally, affect about 7% of the population as carriers, with 2.7% of newborns being born with these conditions. The spectrum of clinical manifestations... Read more

Immunology

view channel
Image: The AI predictive model identifies the most potent cancer killing immune cells for use in immunotherapies (Photo courtesy of Shutterstock)

AI Predicts Tumor-Killing Cells with High Accuracy

Cellular immunotherapy involves extracting immune cells from a patient's tumor, potentially enhancing their cancer-fighting capabilities through engineering, and then expanding and reintroducing them into the body.... Read more

Microbiology

view channel
Image: The T-SPOT.TB test is now paired with the Auto-Pure 2400 liquid handling platform for accurate TB testing (Photo courtesy of Shutterstock)

Integrated Solution Ushers New Era of Automated Tuberculosis Testing

Tuberculosis (TB) is responsible for 1.3 million deaths every year, positioning it as one of the top killers globally due to a single infectious agent. In 2022, around 10.6 million people were diagnosed... Read more