[Application of Warthin-Starry stain, immunohistochemistry and transmission electron microscopy in diagnosis of cat scratch disease].
OBJECTIVE
To evaluate the diagnostic utility of Warthin-Starry silver stain, immunohistochemistry and transmission electron microscopy in the detection of human Bartonella henselae infection and pathologic diagnosis of cat scratch disease (CSD).


METHODS
The paraffin-embedded lymph node tissues of 77 histologically-defined cases of cat scratch disease collected during the period from January, 1998 to December, 2008 were retrieved and studied using Warthin-Starry silver stain (WS stain) and mouse monoclonal antibody against Bartonella henselae (BhmAB stain). Five cases rich in bacteria were selected for transmission electron microscopy.


RESULTS
Under electron microscope, the organisms Bartonella henselae appeared polymorphic, round, elliptical, short rod or bacilliform shapes, ranged from 0.489 to 1.110 microm by 0.333 to 0.534 microm and often clustered together. Black short rod-shaped bacilli arranged in chains or clumps were demonstrated in 61.0% (47/77) of CSD by WS stain. The organisms were located outside the cells and lie mainly in the necrotic debris, especially near the nodal capsule. In 72.7% (56/77) of the cases, dot-like, granular as well as few linear positive signals were observed using BhmAB immunostain and showed similar localization. Positive results for both stains were identified in 59.7% (46/77) of the cases. When applying both stains together, Bartonella henselae was observed in 74.0% (57/77) of the case. The difference between the results obtained by WS stain and BhmAB immunostain was of statistical significance (P < 0.05).


CONCLUSIONS
Bartonella henselae is the causative pathogen of cat scratch disease. WS stain, BhmAB immunostain and transmission electron microscopy are helpful in confirming the histologic diagnosis. Immunostaining using BhmAB can be a better alternative than WS stain in demonstrating the organisms.
Huang
Juan
J
Department of Pathology, West China Hospital, Sichuan University, Chengdu 610041, China.
Dai
Lin
L
Lei
Song
S
Liao
Dian-ying
DY
Wang
Xiao-qing
XQ
Luo
Tian-you
TY
Chen
Yu
Y
Hang
Zhen-biao
ZB
Li
Gan-di
GD
Dong
Dan-dan
DD
Xu
Gang
G
Gu
Zheng-ce
ZC
Hao
Ji-ling
JL
Hua
Ping
P
He
Lei
L
Duan
Fang-lei
FL
D000293:Adolescent; D000328:Adult; D000368:Aged; D000907:Antibodies, Bacterial / Q000097:blood; D018416:Bartonella henselae / Q000276:immunology / Q000302:isolation & purification* / Q000648:ultrastructure; D002372:Cat-Scratch Disease / Q000175:diagnosis* / Q000382:microbiology / Q000473:pathology*; D002648:Child; D002675:Child, Preschool; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods; D007223:Infant; D008198:Lymph Nodes / Q000473:pathology* / Q000648:ultrastructure; D046529:Microscopy, Electron, Transmission; D008875:Middle Aged; D016612:Paraffin Embedding; D013194:Staining and Labeling / Q000379:methods; D055815:Young Adult
D000907:Antibodies, Bacterial