Presence of Chlamydophila pneumoniae DNA in blood cells is a frequent event in patients with the late stage of primary cutaneous lymphomas and with atopic dermatitis

Introduction
Microbial infection and associated super antigens have been implicated in the pathogenesis of cutaneous T-cell lymphoma (CTCL), and many patients die from complicating bacterial infections. It has been postulated that Chlamydophila pneumoniae (C. pneumoniae) infection may be involved in the pathogenesis of Mycosis fungoides (MF) but published data are limited and controversial.

Aim
To analyze the frequency of (C. pneumoniae) DNA presence in blood samples of lymphoma cases.

Material and methods
Using Q-PCR method we analyzed the presence of DNA in the blood samples obtained from 57 patients with CTCL (55 – mycosis fungoides (MF)/Sézary syndrome (SS), one primary cutaneous anaplastic large cell lymphoma (CD30+) and one NKT cell lymphoma) and 3 patients with cutaneous B-cell lymphomas, and 120 individuals from control groups (40 patients with psoriasis, 40 patients with atopic dermatitis and 40 healthy controls).

Results
Chlamydophila pneumoniae DNA was identified in 13 of 55 cases in the MF/SS group (23.6%), in 1 patient with CD30+ large cell lymphoma and in 1 of 3 patients with B-cell lymphoma. The presence of C. pneumoniae was confirmed in 1 of 40 psoriatic patients (2.5%), in 5 of 40 patients with atopic dermatitis (12.5%) and in none of 40 healthy individuals. Presence of C. pneumoniae DNA in MF patients was strongly associated with disease progression; rs = 0.756; p = 0.0123 for groups IA  IVB, and was noted more frequently in advanced (III + IV) stages than in early (I–II) stages (p = 0.0139). There are no differences in the mean age of MF/SS patients with and without infection.

Conclusions
The presence of C. pneumoniae DNA in the blood cells is a frequent event in late stages of MF/SS and may be explained by Th2 shift and suppression of the immune system during the course of the disease.