Nodal inflammatory pseudotumor caused by luetic infection
Fabio Facchetti1, Paolo Incardona, Silvia Lonardi
1Department of Pathology I and II, Spedali Civili-University of Brescia, S Anna Clinic, Brescia, Italy. facchett@med.unibs.it
The American Journal of Surgical Pathology
|November 27, 2008
Summary
Inflammatory pseudotumor of lymph nodes (IPT-LN) can be caused by Treponema pallidum (Tp) infection. Spirochetal etiology should be suspected in IPT-LN, particularly with significant follicular hyperplasia.
Area of Science:
- Pathology
- Infectious Diseases
- Immunology
Background:
- Inflammatory pseudotumor of lymph nodes (IPT-LN) is an uncommon condition of unknown cause.
- A case of IPT-LN associated with Treponema pallidum (Tp) infection prompted this investigation.
Purpose of the Study:
- To investigate the presence of Treponema pallidum (Tp) in inflammatory pseudotumor of lymph nodes (IPT-LN) and extranodal inflammatory pseudotumor (IPT).
Main Methods:
- Analysis of 9 IPT-LN and 9 extranodal IPT cases for Tp using a polyclonal anti-Tp antibody.
- Histopathological examination including immunostains for Tp, CD11c, CD163, HLA-DR, and S100.
Main Results:
- Treponema pallidum (Tp) was detected in 4 out of 9 IPT-LN cases, but not in extranodal IPT.
- Tp were abundant within IPT areas and perivascular tissues, primarily within CD11c+ CD163+ macrophages and S100+ dendritic cells.
- Marked follicular hyperplasia was the only distinct feature associated with Tp-positive cases.
Conclusions:
- A significant proportion of IPT-LN cases are associated with Treponema pallidum (Tp) infection.
- Spirochetal etiology should be considered in IPT-LN, especially when pronounced follicular hyperplasia is present.
- Tp infection of macrophages and dendritic cells suggests immune-mediated mechanisms in IPT pathogenesis.
