Breath test for differential diagnosis between small intestinal bacterial overgrowth and irritable bowel disease: An observation on non-absorbable antibiotics

Table 1 Results of “breath test” with lactulose or glucose in 73 patients with an initial symptoms-based diagnosis of IBS

Definitive diagnosis, n (%)	Breath test	Lactulose	Glucose
SIBO 33 (45.2%)	Positive	32	1
IBS 40 (54.8%)	Negative	40	0

The data are reported as frequency and percentage. SIBO: Small intestine bac-terial overgrowth; IBS: Inflammatory bowel disease.

Table 2 Frequency of symptoms in 40 and 33 patients with a definitive diagnosis of IBS and SIBO respectively

	IBS (n = 40)	SIBO (n = 33)	P
	n (%)	n (%)
Chronic diarrhoea	16 (40.0)	17 (51.5)	NS
Upper abdominal pain	17 (42.5)	14 (42.4)	NS
Lower abdominal pain	30 (75.0)	26 (78.8)	NS
Tenesmus	28 (70.0)	18 (54.5)	NS
Pain to palpation	18 (45.0)	19 (57.6)	NS
Abdominal bloating	32 (80.0)	29 (87.9)	NS
Flatulence	24 (60.0)	24 (72.7)	NS
Reduced body weight	7 (17.5)	9 (27.3)	NS
Nausea	9 (22.5)	15 (45.4)	NS
Steatorrhea	3 (7.5)	1	NS
Megaloblastic anemia	1	-	NS
Stipsis	8 (20.0)	9 (27.3)	NS
Fever	1	2 (6.1)	NS
Other (not specified)	1	0	NS

The data are reported as frequency and percentage.

Table 3 Results of “breath test” and symptom score in 32 patients with defini-tive diagnosis of SIBO treated with rifaximin 1200 mg/d for 7 d

	Before treatment	After treatment with rifaximin
Breath test	Positive	Positive	Negative
	32 (100.0%)	13 (40.6%)	19 (59.4%)
Global	3.48 ± 0.82	3.24 ± 0.80	0.91 ± 0.06
symptom score		NS	P = 0.004
		After a further antibiotic treatment with ciprofloxacin
Breath test		Positive Negative
		12 1
Global symptom score		3.32 ± 0.95 1.00

The test was repeated one week later and, in the subjects with a still positive “breath test”, a further treatment with ciprofloxacin was done (the data are re-ported as frequencies or mean ± standard deviation as appropriate).