Spontaneous remission of giant cell arteritis: possible association with a preceding acute respiratory infection and seropositivity to Chlamydia pneumoniae antibodies

Abstract

Recent epidemiological or immunopathological studies demonstrate the possible association between giant cell arteritis and infectious agents including Chlamydia pneumoniae. A 62-year-old Japanese man with type 1 diabetes mellitus developed biopsy-proven giant cell arteritis after acute upper respiratory infection. Serological examination indicated concurrent re-infection with C. pneumoniae. Clinical manifestations of the vasculitis subsided within a month without any immunosuppressive therapy, and no relapse was observed for the following 12 months. The natural history of this disease is unclear and spontaneous remission is rarely reported. The self-limiting nature of the infection could contribute to this phenomenon.

Keywords: Chlamydia pneumoniae; giant cell arteritis; spontaneous remission.

Fig. 1. Vascular inflammation on computed tomography

(A) Contrast-enhanced computed tomography on the second hospital day demonstrating the thickening of the bilateral femoral arteries and their branches. (B) These findings disappeared after the spontaneous remission of the vasculitis. The imaging was obtained on day 14.

Fig. 2. Vascular inflammation on Gallium scintigraphy

(A) Gallium scintigraphy, which was performed on day 9, showing increased uptake in the bilateral femoral arteries in the acute phase of GCA. (B) These findings disappeared in the follow-up study after 14 months of admission. GCA, giant cell arteritis

Fig. 3. Pathological findings of the temporal artery biopsy specimen

Inflammatory cells infiltrated the muscular layer of the artery. Giant cells were not detected.

Fig. 4. Longitudinal change of the serological tests

Antibodies against Chlamydia pneumoniae during follow-up are indicated. Anti-Cp Ab: Anti-Chlamydia pneumoniae antibody, Cp: Chlamydia pneumoniae

Fig. 5. Clinical course

The development of vasculitis was preceded by several days of fever accompanied by nasal congestion, mild sore throat, and pruritic rash. The patient subsequently achieved remission from biopsy-proven GCA without any immunosuppressive or antimicrobial therapy. CRP: C-reactive protein, TAB: temporal artery biopsy