Clinical Lab News of the Day – Innovative Molecular Diagnostic Test Detects Chagas Disease in Newborns – Diagnostics-Molecular

Innovative molecular diagnostic test detects Chagas disease in newborns

Author: LabMedica Spanish editorial team
Updated July 12, 2024

Parasitic infection Trypanosoma cruzi causes Chagas disease in newborns, with vertical (congenital) transmission accounting for 20% of new cases. This transmission occurs when an infected mother passes the parasite to her baby during pregnancy. Early detection of the parasite in both women and newborns is therefore a critical public health issue. However, the problem is the lack of simple, rapid and reliable testing methods. In high-income countries such as Spain, newborns can be diagnosed using PCR, but this method is expensive and requires trained technicians. In areas where the disease is endemic, two microscopic examinations are usually performed: one at birth and one at two months of age. These tests have low sensitivity and are usually followed by a serological test several months later to detect antibodies against the parasite. Multiple tests and the delay between tests increase the risk of delayed treatment of sick children. Now, an innovative test that combines a DNA extraction system built on a modified 3D printer with loop-mediated isothermal molecular amplification (LAMP) could potentially detect infection with the virus. T. Cruzi in newborns.

This is the conclusion reached by a team of researchers from the Barcelona Institute for Global Health (ISGlobal, Barcelona, ​​Spain) following a study conducted in the Chaco region of Bolivia, an endemic region for Chagas disease. The study, published in the journal Lancet microbeThe team tested a new diagnostic method that combines the LAMP technique with a modified 3D printer to extract DNA from a small blood sample. The method’s performance was compared with PCR and traditional diagnostic approaches (microscopy and serology). The study involved 224 children born to HIV-positive mothers. T. Cruzi for eight months. In total, they identified 23 cases of congenital transmission: nine detected by microscopy at birth and another 14 by serology eight months later.

Image: Molecular diagnostic test LAMP can be used to detect T. cruzi infection, which causes Chagas disease, in newborns (Photo courtesy of ISGlobal)

The LAMP test successfully detected 13 out of 23 cases early in the process, detecting four more cases than microscopy and almost matching the 14 cases detected by PCR. This indicates that the sensitivity of LAMP is superior to microscopy and comparable to that of PCR. An additional advantage of the LAMP test is its potential cost-effectiveness and minimal infrastructure requirements. In accordance with national guidelines for the diagnosis and treatment of congenital Chagas disease, all detected cases were successfully treated, highlighting the vital role of early detection and intervention. The research team emphasized that this study served as a proof of concept for the feasibility of the LAMP diagnostic test, suggesting that more studies should be conducted on a larger scale and in more centers. If its effectiveness is confirmed, the test could also be used to detect acute infections in adults or to assess the effectiveness of treatment.

“In endemic areas, it would be very useful to have a simple, rapid and sensitive test to detect the parasite in newborns, when treatment is most effective,” said Julio Alonso Padilla, a researcher at ISGlobal.

Related links:
ISGlobal