Chlamydophila pneumoniae antibodies in Greek patients with neurological disorders

Abstract number: 1734_126

Pape M., Mandraveli K., Paschalidou M., Gelagoti M., Taskos N., Alexiou-Daniel S.

Objective:Chlamydophila pneumoniae (CP), an intra-cellular parasite, has been implicated in the pathogenesis of a variety of neurological disorders, including atherosclerosis, Alzheimer's disease, optic neuritis (ON), Guillain-Barre (GB) and multiple sclerosis (MS). The correlation of CP with pathogenesis and course of neurological diseases has been studied, but has so far yielded controversial results.

The aim of our study was to investigate a possible relationship between CP infection and neurological disorders in Northern Greek patients.

Methods: Cerebrospinal fluid (CSF) and paired blood samples (S) taken in the acute and the convalescent phase were available from a total of 60 neurological patients (19 males, 31 females). 24 patients had a diagnosis of clinically definite MS, 6 had (ON), 11 had (GB) and 19 had other neurological disorders (OND). Blood specimens and cerebrospinal fluid were tested for the presence of IgG/IgM antibodies against CP using the IFA and the ELISA assay. All the sera were also tested for Coxiella burnetii, Rickettsia typhi, Rickettsia conorii, Bartonella henselae/quintana, Cytomegalovirus, Epstein Barr virus, Respiratory syncytial virus, Mycoplasma pneumoniae and Legionella pneumophila to exclude cross reactions. We also determine the seroprevalence of CP among 60 healthy individuals (control group, 30 men-30 women).

Results: CSF samples were all negative for CP IgG and IgM antibodies. Of the 60 patients, 29 (48%) were seropositive for CP IgG antibodies, having the following diagnoses: MS 15 (25%), ON 3 (5%), GB 7 (12%), OND 3 (5%). Titers 1/64, 1/128, 1/256 were found in 58% (17/29), 28% (8/29), 14% (4/29) respectively. Serological diagnosis of acute CP infection was confirmed by seroconversion only in two GB cases. The seropositivity in the healthy population was 55%.

Conclusions: No significant difference was found in the serology among neurological patients and healthy individuals. CP IgG antibodies were found positive in patients belonging to all groups. This excludes a direct aetiologic relationship between a certain neurological disorder and CP infection. It is possible that a persistent CP infection may play a significant role in the development of the disease by inducing autoimmune reactions.

A surprisingly high rate of CP IgG antibodies was found among patients with ON. Considering that ON may develop to MS, this finding needs to be further investigated.