Supplement bij veertiende jaargang, april 2006 - NVMM

Cystic echinococcosis is caused by the larval stage of
Echinococcus granulosus, the small tapeworm of dogs.
Humans become infected by ingesting the parasite’s eggs
that are shed with the feces of infected dogs. Hepatic
involvement can result in abdominal pain and biliary duct
obstruction. Pulmonary involvement can produce chest
pain, cough, and hemoptysis.
The diagnosis of cystic echinococcosis relies in most cases
on clinical findings and imaging procedures combined
with serology. Serological tests with high specificity and
sensitivity are therefore essential. For this reason we
evaluated the reactivity of IgG1 and IgG4 antibodies to E.
granulosus cyst fluid antigens using the immunoblotting
procedure. Sixty five serum samples from patients with
proven echinococcosis were evaluated. For determination
of specificity, sera from 87 patients with other
parasitic and bacterial infections were studied. Antigens
of 7, 14 and 24 kDa were recognized by IgG1 and IgG4
antibodies from patients with cystic echinococcosis (CE)
and not by patients with other infections. Evaluation of
the specificity and sensitivity of the IgG1 in combination
with the IgG4 immunoblots resulted in 99% specificity
and 95% sensitivity. The immunoblots were also used for
follow up of the immune response of treated CE patients.
Results indicate that patients with good response to
treatment showed decreased IgG1 and/or IgG4 response.
The immunoblots here described have a higher specificity
than the ELISA technique that is used in our laboratory for
routine serological diagnostic of cystic echinococcosis. Due
to the high sensitivity of the ELISA, we propose the use of
the ELISA technique for screening purposes and the IgG1
and IgG4 immunoblots to confirm the positive ELISA
results. The combined results from the Echinococcus-IgG1
and IgG4 are not only useful to serologically confirm
an Echinococcus infection but it provides also additional
information in follow up studies of treated patients.
10.03
Diagnosis of mumps by IgM-elISA in Scotland - an assay
comparison
C.H. Krause, K.E. Templeton
Specialist Virology Centre Edinburgh, Laboratory Medicine,
Edinburgh, United Kingdom
Introduction: Since the end of November 2003, Scotland
has seen an outbreak of mumps with over 4000 confirmed
cases in the last 2 years. The incidence of mumps continues
to be high, particularly in adolescents who were either
unvaccinated or given a single dose of mumps/measles/
rubella vaccine. Laboratory diagnosis is usually requested
on patients with symptoms. Therefore prompt diagnosis
on acute samples is required. Here, the performance of 5
different commercial IgM assays was assessed.
Ned Tijdschr Med Microbiol 2006; 4:Supplement
S43
Methods: The Specialist Virology Laboratory (SVC),
Edinburgh, distributed a serum panel to all Scottish laboratories
that perform mumps diagnosis by IgM-ELISA. The
panel consisted of 45 true positive (TP) and 11 true negative
(TN) serum samples. The TP samples had been confirmed
by virus isolation on a parotid duct swab and/or a 4-fold rise
by complement fixation testing (CFT) on a pair of serum
samples. Date of sample collection after onset of symptoms
(AOS) was recorded. The TN samples consisted of sera from
patients with other infections. Five different commercial
IgM-ELISAs were performed blindly: ELISAs Enzygnost ®
Antiparotitis-Virus/IgM (Dade Behring), Mumps IgM
(Human), Mumps IgM capture EIA (Microimmune Ltd),
Mumps ELISA IgG/IgM (Virotech), and Enzywell Mumps
IgM (Diesse). Results were all reported to SVC.
Results: Sensitivity ranged from 51% to 24%; with the
Microimmune assay being the most sensitive. Assays
performed better on samples taken > 10 days AOS,
although even then mumps-IgM was not detected by
all assays. The Virotech assay was the only assay that
reported mumps-IgM in all serum samples > 10 days AOS.
Specificity was about 82% for most assays.
Conclusion: The anti-mumps-IgM assays assessed are
insensitive and inappropriate for use in acute specimens.
This could be due to the fact that development of antimumps-IgM
is delayed or suppressed in partially immune
individuals. For acute diagnosis laboratories should be
developing the means to direct detection by virus culture
or PCR.
10.04
Use of Raman spectroscopy for the identification of
Burkholderia spp.
H.F.M. Willemse 1 , K. Maquelin 1 , M.J. Scholtes 1 ,
P. Vandamme 2 , A. van Belkum 3 , G.J. Puppels 1
1Erasmus MC, General Surgery/CODT, Rotterdam,
2Universiteit Gent, Laboratorium voor microbiologie, Gent,
Belgium, 3Erasmus MC, Medical Microbiology & Infectious
Diseases, Rotterdam
The Burkholderia cepacia complex (BCC) is a group
of at least nine closely related species. In CF patients
pulmonary BCC infections have a considerable impact
on clinical outcome and may lead to a fatal decline in
lung function known as cepacia syndrome. Members
of the BCC are well recognized as nosocomial and
outbreak related pathogens and are able to colonize CF
patients. Species identification of BCC organisms can be
obtained with phenotypic methods such as automated
commercial systems. Identification using these systems
is doubtful, so confirmatory identification with expensive
and laborious molecular methods is required. A powerful
and inexpensive tool for the rapid identification of micro-