Fecal Microbiota in Early Rheumatoid Arthritis

JUSSI VAAHTOVUO, EVELIINA MUNUKKA, MIKA KORKEAMÄKI, REIJO LUUKKAINEN, and PAAVO TOIVANEN

ABSTRACT.

Objective. To compare the composition of intestinal microbiota of patients with early rheumatoid arthritis (RA) or fibromyalgia (FM), fecal samples were collected from 51 patients with RA and 50 with FM.

Methods. RA patients fulfilled the RA criteria of the American College of Rheumatology, and duration of their disease was ≤ 6 months. Only nonhospitalized patients from outpatient care were included. Patients having extreme diets or previous disease modifying antirheumatic drug or glucocorticoid medication were excluded, as were those taking antibiotics or having gastroenteritis for at least 2 months prior to sampling. Fecal bacterial composition was analyzed with a method based on flow cytometry, 16S rRNA hybridization, and DNA-staining. A set of 8 oligonucleotide probes was used.

Results. In comparison to patients with FM, the RA patients had significantly less bifidobacteria and bacteria of the Bacteroides-Porphyromonas-Prevotella group, Bacteroides fragilis subgroup, and Eubacterium rectale – Clostridium coccoides group. Results from the 8 probes showed a significant overall difference between the 2 patient groups, indicating widespread microbial differences.

Conclusion. These findings support the hypothesis that intestinal microbes participate in the etiopathogenesis of RA. (First Release June 1 2008; J Rheumatol 2008;35:1500–5)

Key Indexing Terms:

MICROBIOTA
RHEUMATOID ARTHRITIS
FIBROMYALGIA
CYTOMETRY
16S rRNA HYBRIDIZATION

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From CyFlo Ltd., Turku; Department of Rheumatology, Satakunta Central Hospital, Rauma; and Department of Medical Microbiology, Turku University, Turku, Finland.

Supported by the Special Governmental Fund for Hospitals (EVO).

J. Vaahtovuo, MD, Managing Director; M. Korkeamäki, BSc (Eng), Head of Research and Development; E. Munukka, BSc (Eng), Research Engineer, CyFlo Ltd.; R. Luukkainen, MD, Senior Physician, Department of Rheumatology, Satakunta Central Hospital; P. Toivanen, MD, Professor Emeritus, Department of Medical Microbiology, Turku University.

J. Vaahtovuo, E. Munukka, and M. Korkeamäki contributed equally to this work.

Address reprint requests to Dr. J. Vaahtovuo, CyFlo Ltd., Itäinen Pitkäkatu 4B, 20520 Turku, Finland. E-mail: jussi.vaahtovuo@cyflo.fi

Accepted for publication March 24, 2008.

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