Hagen Frickmann1, Christine Wegner2, Stefanie Ruben2, Christoph Behrens2, Hans Kollenda3, Rebecca Hinz3, Sandra Rojak4, Norbert G Schwarz5, Ralf Matthias Hagen6, Egbert Tannich2. 1. Department of Microbiology and Hospital Hygiene, Tropical Microbiology and Entomology Unit, Bundeswehr Hospital Hamburg, Hamburg, Germany; Institute for Medical Microbiology, Virology and Hygiene, University Medicine Rostock, Rostock, Germany. Electronic address: Frickmann@bnitm.de. 2. National Reference Centre for Tropical Pathogens, Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany. 3. Department of Microbiology and Hospital Hygiene, Tropical Microbiology and Entomology Unit, Bundeswehr Hospital Hamburg, Hamburg, Germany. 4. Department of Microbiology and Hospital Hygiene, Tropical Microbiology and Entomology Unit, Bundeswehr Hospital Hamburg, Hamburg, Germany; Department of Infectious Diseases and Tropical Medicine, Bundeswehr Hospital Hamburg, Hamburg, Germany. 5. Infectious Disease Epidemiology, Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany. 6. Department of Preventive Medicine, Bundeswehr Medical Academy, Munich, Germany.
Abstract
BACKGROUND: Two commercial PCR assays were assessed in a retrospective study to determine their reliability as tools for the differentiation of Plasmodium species in human blood. METHODS: A total of 1022 blood samples from 817 patients with suspected or confirmed malaria submitted to the German National Reference Centre for Tropical Pathogens were subjected to malaria microscopy using thick and thin blood films as well as to a genus-specific malaria real-time PCR. Parasite-positive samples were analysed by RealStar Malaria S&T PCR Kit 1.0 (altona Diagnostics) and FTD Malaria Differentiation (Fast Track Diagnostics) multiplex real-time PCR assays targeting species-specific Plasmodium DNA. RESULTS: Out of the 1022 blood samples, 247 (24.2%) tested positive for Plasmodium spp. The two multiplex assays showed rather similar performance characteristics and provided concordant species information in 98.9% of samples positive by malaria microscopy and in 95.1% (RealStar) and 96.8% (FTD) of samples positive by genus-specific PCR. Compared to FTD, RealStar revealed slightly reduced sensitivity for submicroscopic, low-level P. falciparum infections, while FTD was unable to detect P. knowlesi. CONCLUSIONS: The two commercial malaria PCR assays assessed are suitable for discriminating Plasmodium species in clinical samples, and can provide additional information in cases of microscopically uncertain findings.
BACKGROUND: Two commercial PCR assays were assessed in a retrospective study to determine their reliability as tools for the differentiation of Plasmodium species in human blood. METHODS: A total of 1022 blood samples from 817 patients with suspected or confirmed malaria submitted to the German National Reference Centre for Tropical Pathogens were subjected to malaria microscopy using thick and thin blood films as well as to a genus-specific malaria real-time PCR. Parasite-positive samples were analysed by RealStar Malaria S&T PCR Kit 1.0 (altona Diagnostics) and FTD Malaria Differentiation (Fast Track Diagnostics) multiplex real-time PCR assays targeting species-specific Plasmodium DNA. RESULTS: Out of the 1022 blood samples, 247 (24.2%) tested positive for Plasmodium spp. The two multiplex assays showed rather similar performance characteristics and provided concordant species information in 98.9% of samples positive by malaria microscopy and in 95.1% (RealStar) and 96.8% (FTD) of samples positive by genus-specific PCR. Compared to FTD, RealStar revealed slightly reduced sensitivity for submicroscopic, low-level P. falciparum infections, while FTD was unable to detect P. knowlesi. CONCLUSIONS: The two commercial malaria PCR assays assessed are suitable for discriminating Plasmodium species in clinical samples, and can provide additional information in cases of microscopically uncertain findings.
Authors: Mariana Aschar; Maria Carmen A Sanchez; Maria de Jesus Costa-Nascimento; Maria de Lourdes R N Farinas; Angélica D Hristov; Giselle F M C Lima; Juliana Inoue; José E Levi; Silvia M Di Santi Journal: Rev Panam Salud Publica Date: 2022-03-28