Whipple's disease: immunospecific and quantitative immunohistochemical study of intestinal biopsy specimens.
Whipple's disease may be diagnosed by periodic acid-Schiff (PAS) staining, electron microscopy, or polymerase chain reaction of intestinal biopsy specimens. The aim of this study was to evaluate the diagnostic value of immunohistochemistry and the quantification of infected cells in intestinal Whipple's disease. A total of 29 duodenal biopsy specimens from 15 patients with untreated and treated Whipple's disease were examined and compared with biopsy specimens from control patients with normal intestinal mucosa or various pathologic processes. Percentages of staining surfaces with PAS stain and antibodies directed against CD68, a macrophage marker, or the Whipple bacillus, Tropheryma whipplei, were studied quantitatively using a computerized system of image analysis. Positive detection of T. whipplei was obtained using immunohistochemistry in all 15 patients with Whipple's disease. No bacteria were detected in any of the negative controls. The use of quantitative image analysis showed a massive intestinal macrophagic infiltration before (20.3%) and after (13.4%) antibiotic therapy completion as compared with controls (2.1%). The 2 detection methods for T. whipplei, PAS stain and immunohistochemistry, were quantitatively similar before therapy (19.9% versus 17.5%), but the immunodetection-based surface area was significantly lower than the PAS staining surface area after therapy (2.8% versus 7.9%). Our findings indicate that immunohistochemistry is highly specific and sensitive and is applicable as a diagnostic method on intestinal tissue specimens to detect T. whipplei during active infection or in retrospective studies.
Lepidi
Hubert
H
Unité des Rickettsies, Université de la Méditerranée, and Hôpital de la Conception, Marseille, France.
Fenollar
Florence
F
Gerolami
Rene
R
Mege
Jean-Louis
JL
Bonzi
Marie-France
MF
Chappuis
Marc
M
Sahel
José
J
Raoult
Didier
D
D039903:Actinobacteria / Q000145:classification / Q000276:immunology / Q000302:isolation & purification*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000907:Antibodies, Bacterial / Q000032:analysis; D000942:Antigens, Bacterial / Q000276:immunology; D015703:Antigens, CD / Q000276:immunology; D015214:Antigens, Differentiation, Myelomonocytic / Q000276:immunology; D015415:Biomarkers / Q000032:analysis; D001706:Biopsy; D004386:Duodenum / Q000378:metabolism / Q000382:microbiology / Q000473:pathology*; D005260:Female; D005487:Foam Cells / Q000378:metabolism / Q000382:microbiology / Q000473:pathology; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007150:Immunohistochemistry / Q000379:methods*; D007413:Intestinal Mucosa / Q000378:metabolism / Q000382:microbiology / Q000473:pathology; D008297:Male; D008875:Middle Aged; D010503:Periodic Acid-Schiff Reaction; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D008061:Whipple Disease / Q000378:metabolism / Q000382:microbiology / Q000473:pathology*; D000097382:CD68 Molecule
D000907:Antibodies, Bacterial; D000942:Antigens, Bacterial; D015703:Antigens, CD; D015214:Antigens, Differentiation, Myelomonocytic; D015415:Biomarkers; C067980:CD68 antigen, human; D000097382:CD68 Molecule