Irritable bowel syndrome and small intestinal bacterial overgrowth: Meaningful association or unnecessary hype

Table 1 Summary of prevalence of small intestinal bacterial overgrowth in irritable bowel syndrome by different diagnostic methods n (%)

Ref.	Type of the study	Frequency of SIBO in cases	Frequency of SIBO in controls	Methane producers in cases	Methane producers in controls	Method for diagnosis
Park et al[86]	Prospective (Case-control)	34/76 (44.7)	16/40 (40)	19/76 (25)	10/40 (25)	LHBT
Scarpellini et al[88]	Prospective (Case-control)	28/43 (65)	4/56 (7)	4/43 (9.3)	0	LHBT
Carrara et al[14]	Prospective	55/127 (43)	NCG	ND	ND	LHBT
Mann and Limoges-Gonzales[87]	Prospective	89/258 (34.5)	NCG	ND	ND	LHBT
Nucera et al[89]	Prospective	64/98 (65)	NCG	ND	ND	LHBT
Pimentel et al[17]	Prospective	157/202 (78)	NCG	ND	ND	LHBT
Sachdeva et al[18]	Prospective (Case-control)	14/59 (23.7)	1/37 (2.7)	5/59 (8.5)	9/37 (24.3)	GHBT
Reddymasu et al[90]	Prospective	35/98 (36)	NCG	Data NA	ND	GHBT
Lombardo et al[91]	Prospective (Case-control)	49/200 (24.5)	3/50 (6)	ND	ND	GHBT
Ford et al[74]	Meta-analysis	595/1921 (31)	NCG	ND	ND	GHBT
Parodi et al[92]	Prospective (Case-control)	21/130 (16.1)	3/70 (4.2)	34/130 (26)	Data NA	GHBT
Rana et al[93]	Prospective (Case-control)	25/225 (11.1)	1/100 (1)	ND	ND	GHBT
Majewski et al[94]	Prospective (Case-control)	93/204 (46)	NCG	27/204 (13.2)	ND	GHBT
Cuoco and Salvangnini[75]	Retrospective	44/96 (45.8)	NCG	ND	ND	GHBT
Lupascu et al[95]	Prospective (Case-control)	20/65 (31)	4/102 (4)	ND	ND	GHBT
Ghoshal et al[16]	Prospective (Case-control)	11/129 (8.5)	1/51(2)	ND	ND	GHBT
Posserud et al[12]	Prospective (Case-control)	6/162 (4)	1/26 (4)	ND	ND	Hydrogen breath test and culture of small bowel aspirate

SIBO: Small intestinal bacterial overgrowth; IBS: Irritable bowel syndrome; LHBT: Lactulose hydrogen breath test; GHBT: Glucose hydrogen breath test; NCG: No control group; ND: Not done; NA: Not available; n: Number of cases and controls.