BACKGROUND: Bloating, the chief complaint of patients with small intestinal bacterial overgrowth (SIBO), is a common symptom in patients with fibromyalgia (FM).

AIM: The aim of this study is to test the hypothesis that 1. SIBO is associated with FM and 2. SIBO treatment reduces FM symptoms.

METHODS: Forty-six patients with FM (ACR criteria) entered a double blind randomized placebo controlled trial. A lactulose hydrogen breath test (LHBT) to diagnose SIBO, a tenderpoint examination and questionnaire were performed at baseline and at every subsequent visit. Subjects were randomized to receive neomycin 500 mg twice daily (liquid) or matched placebo for 10 days. After completion of this treatment, subjects with persistent SIBO received antibiotics (open label) until eradication was confirmed by LHBT. T-test was used to compare the symptom scores of patients who were eradicated vs. not eradicated for SIBO.

RESULTS: 1) Forty-two of 46 FM patients (91.3%) were found to have SIBO; 2) only 6 out of 20 patients (30%) in the neomycin group achieved eradication in the blinded arm; 3) with only 6 responders, there was no difference in the score before and after the 10 d treatment; 4) 28 patients went on to open label treatment with 17 (60.7%) achieving eradication; 5) when scores after eradication on double blind or open treatment were compared to baseline, there was significant improvement in Tender Points, Tender Point Score, Hamilton Depression Scale, FIQ, Beck Depression Scale, Health Assessment Questionnaire (HAQ), VAS-Pain, VAS-Memory/Concentration and IBS-QOL (selections shown in table).

		Eradicated (n=25)			Not Eradicated (n=15)		Eradicated vs. Not Eradicated
Observation	Baseline	Eradicated	p-value	Baseline	Eradicated	p-value	(p-value)
Tender Points (TP)	13.3 ±2.9	10.3 ±4.2	0.01	13.6 ±2.0	12.1 ±4.1	NS	NS
TP Score	20.3 ±7.0	15.0 ±9.1	0.01	23.7 ±8.0	19.9 ±9.7	NS	NS
FIQ	66.8 ±18.2	49.5 ±17.7	0.0001	72.7 ±19.9	64.1 ±20.9	0.04	0.02
VAS-pain (mm)	80.7 ±22.7	52.4 ±28.5	0.00005	87.5 ±19.6	76.2 ±25.2	NS	0.01
HAQ	42.4 ±10.5	37.7 ±10.1	0.005	45.1 ±11.2	43.9 ±12.1	NS	NS

CONCLUSIONS: 1. SIBO is associated with fibromyalgia, 2. Eradication of SIBO decreases symptoms in fibromyalgia.

KEYWORDS: Fibromyalgia

American College of Rheumatology Meeting, November 13-17, 1999, Boston, MA - Poster Session F: Soft Tissue & Regional Musculoskeletal Disorders II (12:30 PM-2:00 PM)