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Increased levels of
circulating IL-16 and apoptosis markers are related to the activity of
Whipple's disease.PLoS
ONE. 2007 Jun 6;2(6):e494.
BACKGROUND: Whipple's
disease (WD) is an infectious disease caused by Tropheryma whipplei, which
replicates in macrophages and induces the release of interleukin (IL)-16, a
substrate of caspase 3, and macrophage apoptosis. The disease is
characterized by intestinal, cardiac or neurological manifestations; its
diagnosis is based on invasive analysis requiring tissue biopsies or
cerebrospinal fluid puncture. The disease progression is slow and often
complicated by relapses despite empirical antibiotic treatment.
METHODOLOGY/PRINCIPAL FINDINGS: We monitored circulating levels of IL-16 and
nucleosomes in 36 French patients with WD; among them, some patients were
enrolled in a longitudinal follow-up. As compared to control subjects, the
circulating levels of both IL-16 and nucleosomes were increased in untreated
patients with WD presenting as intestinal, cardiac or neurological
manifestations. This finding was specific to WD since the circulating levels
of IL-16 and nucleosomes were not increased in patients with unrelated
inflammatory diseases such as inflammatory bowel disease or Q fever
endocarditis. We also found that increased levels of IL-16 and nucleosomes
were related to the activity of the disease. Indeed, successful antibiotic
treatment decreased those levels down to those of control subjects. In
contrast, patients who suffered from relapses exhibited circulating levels
of IL-16 and nucleosomes as high as those of untreated patients.
CONCLUSIONS/SIGNIFICANCE: Circulating levels of both IL-16 and nucleosomes
were increased in WD. This finding provides simple and non-invasive tools
for the diagnosis and the prognosis of WD.
Whipple's
disease.Schweiz
Rundsch Med Prax. 2007 Jan 10;96(1-2):13-7.
Whipple's disease is a rare infectious disorder affecting mostly middle aged
men. The causative organism, Tropheryma whipplei, recently has been
cultivated and phylogenetically identified as an actinomycete. The rareness
of the disease despite the ubiquitous occurence of T. whipplei presumably is
related to a predisposing defect in cellular immunity. The diagnosis usually
can be established by small bowel biopsy, but is frequently delayed due to
protean clinical manifestations. The initiation of antibiotic treatment in
most cases results in clinical remission, however, a significant number of
patients is refractory to antimicrobial therapy or has a relapsing course.
Current
concepts of immunopathogenesis, diagnosis and therapy in Whipple's disease.Curr
Med Chem. 2006;13(24):2921-6.
Whipple's disease (WD) is a rare chronic infectious disorder caused by the
rod- shaped bacterium Tropheryma whipplei. The disorder is characterized
clinically by arthralgia, abdominal pain, diarrhea, malabsorbtion and
progressive weight loss. Other important sites of infection include the
heart (resulting in the clinical picture of endocarditis and heart failure)
and the central nervous system (CNS) (manifestations include confusion,
memory loss, focal cranial nerve signs, nystagmus and ophtalmoplegia). The
bacterium is presumed to be ubiquitously present. A defect in cellular
immune response may predispose patients for an infection with T. whipplei
and this might explain the rarity of the disorder despite the ubiquitous
bacterial presence. The presumed immunological defect is likely to be quite
specific for T. whipplei, since patients are not generally affected by other
infections. Decreased production of Interleukin(IL)-12, IL-2 and Interferon
(IFN)-g accompanied by an increased secretion of IL-4 are the main features
of this defective immunological response. The finding of periodic
acid-Schiff (PAS)-positive macrophages in the lamina propria of tissue
samples obtained by duodenal biopsy usually establishes the diagnosis. The
PAS-positive inclusions represent the remnants of the bacteria. Attempts to
isolate the causative agent were unsuccessful for nearby 100 years after the
first recognition of the disease. In the year 2000, the bacterium was
finally successfully grown on a human fibroblast cell line. Untreated WD
patients suffer from a chronic progressive disorder which possibly leads to
death. Most patients show a fast clinical improvement to antibiotic therapy,
but clinical relapses are described frequently. There is a number of
patients, unable to eradicate the bacterium even after several antibiotic
treatments and patients with CNS disease, in both of whom alternative
therapy strategies are necessary. |