Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2018 Sep 8;218(8):1296-1305.
doi: 10.1093/infdis/jiy319.

Use of Capillary Blood Samples Leads to Higher Parasitemia Estimates and Higher Diagnostic Sensitivity of Microscopic and Molecular Diagnostics of Malaria Than Venous Blood Samples

Johannes Mischlinger  1   2   3   4   5   6 , Paul Pitzinger  1   2 , Luzia Veletzky  1   2   5   6 , Mirjam Groger  1   2   5   6 , Rella Zoleko-Manego  2   3   4   5   6 , Ayola A Adegnika  2   3   4 , Selidji T Agnandji  2   3   4 , Bertrand Lell  2   3   4 , Peter G Kremsner  2   3   4 , Egbert Tannich  7   8 , Ghyslain Mombo-Ngoma  2   3   4   5   6   9 , Benjamin Mordmüller  2   3   4 , Michael Ramharter  5   6   8
Affiliations

Use of Capillary Blood Samples Leads to Higher Parasitemia Estimates and Higher Diagnostic Sensitivity of Microscopic and Molecular Diagnostics of Malaria Than Venous Blood Samples

Johannes Mischlinger et al. J Infect Dis. .

Abstract

Background: Diagnosis of malaria is usually based on samples of peripheral blood. However, it is unclear whether capillary (CAP) or venous (VEN) blood samples provide better diagnostic performance. Quantitative differences of parasitemia between CAP and VEN blood and diagnostic performance characteristics were investigated.

Methods: Patients were recruited between September 2015 and February 2016 in Gabon. Light microscopy and quantitative polymerase chain reaction (qPCR) measured parasitemia of paired CAP and VEN samples. CAP and VEN performance characteristics using microscopy were evaluated against a qPCR gold standard.

Results: Microscopy revealed a median parasitemia of 495/μL in CAP and 429/μL in VEN samples, manifesting in a 16.6% (P = .04) higher CAP parasitemia compared with VEN parasitemia. Concordantly, in qPCR -0.278 (P = .006) cycles were required for signal detection in CAP samples. CAP sensitivity of microscopy relative to the gold standard was 81.5% vs VEN sensitivity of 73.4%, while specificities were 91%. CAP and VEN sensitivities dropped to 63.3% and 45.9%, respectively, for a subpopulation of low-level parasitemias, whereas specificities were 92%.

Conclusions: CAP sampling leads to higher parasitemias compared to VEN sampling and improves diagnostic sensitivity. These findings may have important implications for routine diagnostics, research, and elimination campaigns of malaria.

PubMed Disclaimer

Publication types