Accuracy of urea breath test in Helicobacter pylori infection: Meta-analysis

Table 1 Baseline characteristics of the included studies

Ref.	Country	Year	No. of patients	Study design	UBT (13C/14C)	Infrared assisted	Reference standard	Mean age (mean ± SD)	Females		UBT threshold	Time
Allardyce et al[13]	New Zealand	1997	63	Cross-sectional	14C	No	Histo or (Biopsy and rapid urea test)	56.5	26	41%	82% DPM	30 min and 60 min post ingestion
Bruden et al[16]	Estonia	2011	280	Cross-sectional	13C	No	Culture or (Histo and RUT)	53.5	185	66%	≥ 5%	NA
Calvet et al[27]	Spain	2009	199	Cross-sectional	13C	Yes	Any two positive (Histopathology, RUT, UBT, and fecal serology)	48.2 ± 14.2	107	53%	8.5%	20 min after drinking solution
Chen et al[29]	Taiwan	2003	586	Cross-sectional	13C	Yes	Culture alone or RUT	45.7 ± 13.3	280	46.6%	≥ 2%	20 min after drinking solution
Chen et al[25]	Japan	2000	169	Cross-sectional	13C	No	Combined (Histo and serology)	53.9 ± 15.7	68	40%	2.5%	20 min after normal respiration
Gatta et al[30]	Italy	2003	200	Cross-sectional	13C	No	Combined (Histology and rapid urease) and/or culture	53 ± 13	113	56%	NA	30 min post ingestion
Gomes et al[22]	Brazil	2002	137	Cross-sectional	14C	No	Combined (Histo and RUT)	46.7 ± 16.6	67	45%	1000-2000 CPM	30 min post ingestion
Gomollon et al[17]	Spain	2003	314	Cross-sectional	13C	No	Culture and/or Combined (Histo and RUT)	54.1 ± 18	168	53.5%	≥ 5%	30 min post ingestion
Gurbuz et al[23]	Turkey	2005	65	Cross-sectional	14C	No	Combind tests (Histo and RUT)	42.4 ± 15.5	46	67.7%	> 50 CPM	10 min after drinking solution
Hahn et al[31]	United States	2000	100	Cross-sectional	13C	No	Combined (Histo, UBT and serology)	58.8 ± 14	9	13.4%	> 2.3%	30 min after administration
Hilker et al[14]	Germany	1996	174	Cross-sectional	13C	No	Histo	46	106	60.9%	> 250	30 min after administration
van der Hulst et al[26]	Italy	1999	544	Cross-sectional	13C	Yes	Histo and culture	46.5	379	62.7%	> 5%	30 min after administration
Marshall et al[32]	United States	1990	153	Cross-sectional	14C	No	Combined (Culture, RUT and histo)	--	77	50%	> 6%	30 min after administration
Ortiz-Olvera Nayeli et al[18]	Mexico	2007	88	Cross-sectional	13C	No	Culture and/or combined (Histo and RUT)	45 ± 15	49	55.6%	> 4.22%	30 min after administration
Ozdemir et al[28]	Turkey	2008	89	Cross-sectional	14C	No	Combined; any 2 positive ( RUT, PCR and histo)	45 ± 13	59	66%	> 25 CPMas Heliprobe	10 min after drinking solution
Oztürk et al[15]	Turkey	2003	75	Cross-sectional	14C	No	Histology	41 ± 14	56	74.6%	100 DPM	NA
Peng et al[19]	Taiwan	2009	100	Cross-sectional	13C	Yes	Culture or combind (Histo and RUT)	55	44	55%	4.8%	15 min after drinking solution
Perri et al[20]	Belgium	1998	172	Cross-sectional	13C	No	Histo and/or culture	39.7 ± 14.1	81	47%	3.3%	Every 15 min for 1 h after ingestion ofthe urea solution
Kopański et al[3]	Poland	2002	92	Cross-sectional	14C	No	Combined (Culture, serology, UBT and urine test for C-urea)	45.5	36	39%	> 5%	30 min after administration
Rasool et al[24]	Pakistan	2007	94	Cross-sectional	14C	No	Two reference tests. Patient did both separately: (1) Histo; (2) RUT	40.8 ± 12.8	34	36%	> 50 CPM	After 10 min
Riepl et al[33]	Austria	2000	100	Cross-sectional	13C	Yes	Combined 3 tests (Histo, UAT and culture)	51.6 ± 1.4	49	49%	> 4%	NA
Surveyor et al[21]	Australia	1989	63	Cross-sectional	14C	No	Histo and/or culture	58.8 ± 14.5	30	47%	NA	Every 5 min for 30 min
Valdeperez et al[12]	Spain	2003	85	Cross-sectional	13C	No	Histo and RUT	41.6	44	50.5%	NA	30 min after administration

Histo: Histopathology; RUT: Rapid urea test; UAT: Urea antigen; CLO: The CLOtest™ (Ballard Medical Products, Draper, UT, United States) was used for RUT; PCR: Polymerase chain reaction; NA: Not available; CPM: Counts per min; UBT: Urea breath test; DPM: Disintegrations per minute.

Table 2 Test values of included studies

Ref.	TP	FP	FN	TN	Total
Allardyce et al[13]	24	2	0	37	63
Bruden et al[16]	131	24	9	116	280
Calvet et al[27]	102	9	11	77	199
Chen et al[29]	361	8	10	205	584
Chen et al[25]	135	1	0	26	162
Gatta et al[30]	113	1	0	86	200
Gomes et al[22]	112	1	3	21	137
Gomollon et al[17]	249	0	4	61	314
Gurbuz et al[23]	26	8	3	28	65
Hahn et al[31]	4	9	0	54	67
Hilker et al[14]	76	4	0	94	174
van der Hulst et al[26] part 1	255	14	14	231	514
van der Hulst et al[26] part 2	161	3	12	72	248
Marshall et al[32]	101	0	3	49	153
Ortiz-Olvera Nayeli et al[18]	46	2	5	28	81
Ozdemir et al[28]	57	0	2	30	89
Oztürk et al[15]	48	5	0	20	73
Peng et al[19]	53	7	0	40	100
Perri et al[20]	121	1	5	46	173
Kopański et al[3]	75	2	0	17	94
Rasool et al[24]	61	2	5	26	94
Riepl et al[33]	30	7	7	63	107
Surveyor et al[21]	30	2	2	25	59
Valdeperez et al[12]	61	0	5	19	85

TP: True positive; FP: False positive; FN: False negative; TN: True negative.

Table 3 Subgroup analysis

Subgroup	No. of studies	Sensitivity	Specificity
UBT 13C	14	0.96 (0.95-0.97)	0.94 (0.92-0.95)
UBT 14C	9	0.97 (0.95-0.98)	0.91 (0.87-0.94)
Infrared assisted UBT	5	0.95 (0.93-0.96)	0.93 (0.91-0.95)
Infrared not assisted UBT	18	0.97 (0.96-0.98)	0.93 (0.91-0.95)

UBT: Urea breath test.