Prospective European-wide multicentre study on a blood based real-time PCR for the diagnosis of acute schistosomiasis.
BACKGROUND
Acute schistosomiasis constitutes a rare but serious condition in individuals experiencing their first prepatent Schistosoma infection. To circumvent costly and time-consuming diagnostics, an early and rapid diagnosis is required. So far, classic diagnostic tools such as parasite microscopy or serology lack considerable sensitivity at this early stage of Schistosoma infection. To validate the use of a blood based real-time polymerase chain reaction (PCR) test for the detection of Schistosoma DNA in patients with acute schistosomiasis who acquired their infection in various endemic regions we conducted a European-wide prospective study in 11 centres specialized in travel medicine and tropical medicine.


METHODS
Patients with a history of recent travelling to schistosomiasis endemic regions and freshwater contacts, an episode of fever (body temperature ≥38.5°C) and an absolute or relative eosinophil count of ≥700/μl or 10%, were eligible for participation. PCR testing with DNA extracted from serum was compared with results from serology and microscopy.


RESULTS
Of the 38 patients with acute schistosomiasis included into the study, PCR detected Schistosoma DNA in 35 patients at initial presentation (sensitivity 92%). In contrast, sensitivity of serology (enzyme immunoassay and/or immunofluorescence assay) or parasite microscopy was only 70% and 24%, respectively.


CONCLUSIONS
For the early diagnosis of acute schistosomiasis, real-time PCR for the detection of schistosoma DNA in serum is more sensitive than classic diagnostic tools such as serology or microscopy, irrespective of the region of infection. Generalization of the results to all Schistosoma species may be difficult as in the study presented here only eggs of S. mansoni were detected by microscopy. A minimum amount of two millilitre of serum is required for sufficient diagnostic accuracy.
Department of Intensive Care Medicine, University Medical Centre Hamburg-Eppendorf, 20246, Hamburg, Germany. d.wichmann@uke.de
Dominic
D
Wichmann
Sven
S
Poppert
Heidrun
H
Von Thien
Joannes
J
Clerinx
Sebastian
S
Dieckmann
Mogens
M
Jensenius
Philippe
P
Parola
Joachim
J
Richter
Mirjam
M
Schunk
August
A
Stich
Philipp
P
Zanger
Gerd D
GD
Burchard
Egbert
E
Tannich
D000208:Acute Disease; D000328:Adult; D000368:Aged; D000818:Animals; D018509:DNA, Helminth; D005060:Europe; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D060888:Real-Time Polymerase Chain Reaction; D012547:Schistosoma / Q000235:genetics*; D012552:Schistosomiasis / Q000175:diagnosis*; D055815:Young Adult
D018509:DNA, Helminth