Standard vs magnifying narrow-band imaging endoscopy for diagnosis of Helicobacter pylori infection and gastric precancerous conditions

Table 1 Baseline characteristics of the study population

Characteristic	n = 254
Age (yr, mean ± SD)	45.9 ± 14.6
Sex, male, n (%)	119 (46.9)
Indication for endoscopy, n (%)
Screening	132 (52.0)
Dyspepsia	42 (16.5)
Abdominal pain	47 (18.5)
Other	33 (13.0)
Endoscopic diagnosis, n (%)
Peptic ulcer	11 (4.3)
Gastric neoplasia	25 (9.8)
Non-neoplastic polyp	19 (7.5)
Chronic active gastritis	135 (53.1)
Helicobacter pylori infection, n (%)	163 (64.2)
Gastric atrophy, n (%)
None/mild	117 (66.9)
Moderate	37 (21.1)
Severe	21 (12.0)
Intestinal metaplasia, n (%)
None	115 (65.7)
Antrum only	22 (12.6)
Corpus	38 (21.7)
Serum PG (ng/mL, mean ± SD)
PG I	64.4 ± 32.4
PG II	20.5 ± 14.7
PG I/II ratio	4.11 ± 2.2
Serum gastrin (pg/mL, mean ± SD)	123.1 ± 149.9

SD: Standard deviation; PG: Pepsinogen.

Table 2 Helicobacter pylori gastritis, gastric atrophy, and intestinal metaplasia observed by standard and magnifying narrow-band imaging endoscopy

Endoscopy	H. pylori gastritis		Gastric atrophy		Intestinal metaplasia
	Negative	Positive	None/mild	Moderate/severe	None/antrum	Corpus
	(n = 91)	(n = 163)	(n = 117)	(n = 58)	(n = 137)	(n = 38)
Standard
Normal	87/100 (87.0)	13/100 (13.0)	70/72 (97.2)	2/72 (2.8)	71/72 (98.6)	1/72 (1.4)
Type A	4/47 (8.5)	43/47 (91.5)	24/33 (72.7)	9/33 (27.3)	25/33 (75.8)	8/33 (24.2)
Type B	0/84 (0)	84/84 (100)	13/50 (26.0)	37/50 (74.0)	24/50 (48.0)	26/50 (52.0)
Type C	0/23 (0)	23/23 (100)	10/20 (50.0)	10/20 (50.0)	17/20 (85.0)	3/20 (15.0)
M-NBI
Normal	87/93 (93.5)	6/93 (6.5)	69/69 (100)	0/69 (0)	69/69 (100)	0/69 (0)
Type Z-1	3/127 (2.4)	124/127 (97.6)	46/85 (54.1)	39/85 (45.9)	59/85 (69.4)	26/85 (30.6)
Type Z-2	1/27 (3.7)	26/27 (96.3)	2/17 (11.8)	15/17 (88.2)	7/17 (41.2)	10/17 (58.8)
Type Z-3	0/7 (0)	7/7 (100)	0/4 (0)	4/4 (100)	2/4 (50.0)	2/4 (50.0)

M-NBI: Magnifying narrow-band imaging; H. pylori: Helicobacter pylori.

Table 3 Diagnostic performance of standard and magnifying narrow-band imaging endoscopy for Helicobacter pylori gastritis, gastric atrophy, and intestinal metaplasia

Endoscopy	Diagnosis	Sensitivity (%)	Specificity (%)	PPV (%)	NPV (%)	Accuracy (%)	AUC
Standard	H. pylori gastritis	92.0a	95.6	97.4	87.0	93.3	0.93
	Moderate to severe atrophy	96.6	59.8	54.4	97.2	72.0	0.78
	Intestinal metaplasia, corpus	97.4	51.8	35.9	98.6	61.7	0.74
M-NBI	H. pylori gastritis	96.3a	95.6	97.5	93.5	96.1	0.96
	Moderate to severe atrophy	100	59.0	54.7	100	72.6	0.79
	Intestinal metaplasia, corpus	100	50.4	35.8	100	61.1	0.75

^aP = 0.016, McNemar test indicated a significant difference in sensitivity for diagnosis of Helicobacter pylori infection between standard and magnifying narrow-band imaging endoscopy. M-NBI: Magnifying narrow-band imaging; PPV: Positive predictive value; NPV: Negative predictive value; AUC: area under the curve; H. pylori: Helicobacter pylori.

Table 4 Serum pepsinogen I/II ratio according to gastric mucosal pattern observed by standard and magnifying narrow-band imaging endoscopy

PG I/II ratio	Standard (%)				M-NBI (%)
	Normal	Type A	Type B	Type C	Normal	Type Z-1	Type Z-2	Type Z-3
> 3 (n = 71)	38/39 (97.4)	16/25 (64.0)	13/46 (28.3)	4/17 (23.5)	36/36 (100)	33/72 (45.8)	2/15 (13.3)	0/4 (0)
≤ 3 (n = 56)	1/39 (2.6)	9/25 (36.0)	33/46 (71.7)	13/17 (76.5)	0/36 (0)	39/72 (54.2)	13/15 (86.7)	4/4 (100)

PG: Pepsinogen; M-NBI: Magnifying narrow-band imaging.

Table 5 Logistic regression analysis of the associations of endoscopic mucosal patterns with gastric precancerous conditions

Mucosal pattern	Moderate to severe atrophy		Intestinal metaplasia, corpus		PG I/II ratio ≤ 3
	OR (95%CI)	P value	OR (95%CI)	P value	OR (95%CI)	P value
Standard		0.001		0.189		0.004
Type A	1 (ref.)		1 (ref.)		1 (ref.)
Type B + C	5.56 (2.07-14.92)		1.96 (0.72-5.33)		4.48 (1.60-12.54)
M-NBI		0.007		0.162		0.029
Type Z-1	1 (ref.)		1 (ref.)		1 (ref.)
Type Z-2 + Z-3	8.67 (1.82-41.30)		2.12 (0.74-6.07)		5.69 (1.19-27.18)

M-NBI: Magnifying narrow-band imaging; PG: Pepsinogen; OR: Odds ratio; CI: Confidence interval.