Prevalence of antibiotic resistance in Helicobacter pylori: A recent literature review

Table 1 Mode of action, resistance mechanisms of antimicrobial agents used for treatment of Helicobacter pylori infection

Antibiotic	Mode of action	Resistance mechanisms
Metronidazole	Electron reduction processes, leads to the formation of nitro-anion radicals and subsequent DNA damage	(1) Poor drug uptake and/or increased drug efflux; (2) enhanced activity of DNA repair enzymes; (3) increased oxygen scavenging abilities; and (4) decreased antibiotic activation arising from changes in metronidazole-reducing enzymes[16]
Clarithromycin	The inhibition of protein synthesis by binding and slowing down the activity of the bacterial ribosomal unit[17]	rRNA-point mutations
Amoxicillin	The inhibition cell wall synthesis	pbp gene mutations, membrane permeability alterations and efflux pumps[17]
Tetracycline	Reversible inhibition protein synthesis	Three contiguous nucleotides mutation in the 16S rRNA gene[17]
Fluoroquinolones	Inhibiting DNA gyrase, type II topoisomerase, and topoisomerase IV[17]	Point mutations in the quinolones resistance determining regions
Rifabutin	Inhibits the b-subunit of H. pylori DNA-dependent RNA polymerase encoded by the rpoB gene[18]	Mutation of the rpoB gene[18]

H. pylori: Helicobacter pylori.

Table 2 Antibiotic resistance rates in different continental areas

Region (n)	Cla	Amo	Met	Tet	Lev	Rif	Fur
	%	%	%	%	%	%	%
Asia (23748)	27.46	23.61	46.57	7.38	25.28	12.45	23
South America (587)	12.88	6.56	52.85	0	21.23	NR	0
North America (818)	30.8	2	30.5	0	19	NR	NR
Europe (26024)	22.11	0.35	31.19	1.15	14.19	1	NR
Africa (831)	5.46	40.87	75.02	50	15	NR	NR
Total (52008)	19.74	14.67	47.22	11.70	18.94	6.75	11.5

Amo: Amoxicillin; Cla: Clarithromycin; Met: Metronidazole; Tet: Tetracycline; Lev: Levofloxacin; Rif: Rifabutin; Fur: Furazolidon; n: Number; NR: Not reported.

Table 3 Quantitative data of the articles

Countries	Year	Isolates	Cla	Amo	Met	Tet	Lev	Rif	Fur	Method	Ref.
		(N)	(%)	(%)	(%)	(%)	(%)	(%)	(%)
	2014	95	33.7							E-Test	[20]
	2013	82	17.1	9.8	64.4	0				DDM	[21]
	2013	78	15.3	6.4	55.1					DDM	[22]
Iran	2012	150	34	10	78.6	9.3	5.3			E-T,ADM	[23]
	2012	112	14.3	28.6	76.8	18.7		28.6		DDM	[24]
	2011	197	45.2	23.9	65.5	37.1			61.4	DDM	[25]
	2011	42	14.3	2.4	40.5	4.8				ADM	[26]
	2010	121	5	20	44	3				E-Test	[27]
	2010	132	30	6.8	73.4	9				E-Test	[28]
	2014	73	80.8	0	58.9		12.3			E-Test	[29]
	2013	17731	21.5	0.1	95.4		20.6		0.1	ADM	[30]
China	2011	73	84.9	0	61.6	0	13.7	6.8		PCR	[31]
	2010	374	37.2	0.3	63.9	1.2	50.3			E-Test	[32]
	2009	36	8.3	33.3	94.4		0		16.7	DDM	[33]
	2014	124	36.2	0	2.1					E-Test	[34]
Japan	2014	135	25.9		20.7					E-Test	[35]
	2014	1073	31.1		40.2					ADM	[36]
	2013	204	86.4	8.2	71.3		57			ADM	[37]
	2011	153	55.6							PCR	[38]
	2010	61	36.1	0	14.8					ADM	[39]
	2014	212	8.5	9	36.3	0				ADM	[40]
South Korea	2013	165	11.5	2.45	50.7	0	24.55			ADM	[41]
	2013	150		6						ADM	[42]
	2012	185	10.8	2.2	30.3	0.05				ADM	[43]
	2014	161	1.2		36.6					E-Test	[44]
Malaysia	2014	102	6.8	0	32.3	0	6.8	0		E-Test	[45]
	2011	90	0	0	75.5		0	14.4		E-Test	[46]
	2011	187	2.1	0	37.4	0	1			E-Test	[47]
	2009	187	2.1							E-Test	[48]
	2014	46	47.8	54.3	73.9	4.3				E-Test	[49]
Pakistan	2012	178	36	37	89	12				ADM	[50]
	2010	92	33	2	48					E-Test	[51]
	2014	98	23.5	3.9	11.7					DDM	[52]
	2012	149	18.2	0	45.5		18.2			E-Test	[53]
Turkey	2012	61	21.3	0	42.6	9.1	3.3			DDM	[54]
	2009	31	41.9	3.2	41.9	3.2				E-Test	[55]
	2009	38	13.5							ADM	[56]
Taiwan	2014	61	35.3	0	17.6	0	23.5			E-Test	[57]
	2009	180	10.6	0	26.7		9.4			E-Test	[58]
Thailand	2009	120	29.2							PCR	[59]
UAE	2010	26	19.2							E-Test	[60]
India	2014	80	58.8	72.5	83.8	53.8	13.8		13.8	DDM	[61]
Vietnam	2013	103	33	0	69.9	5.8	18.4			E-Test	[62]
South American
	2014	54	11.1	1.9						E-Test	[63]
Brazil	2013	77	19.5	10.4	40	0			0	ADM	[64]
	2011	39	8	0	51	0	23		0	ADM	[65]
Colombia	2012	203	19.8	20.5						ADM	[66]
Cuba	2010	40	10		85					E-Test	[67]
										PCR
Peru	2011	95					36.9			ADM	[68]
										DDM
Uruguay	2009	79	8.9	0	35.4	0	3.8			E-Test	[69]
North America
Mexico	2011	90	5.5		19					E-Test	[70]
Canada	2009	42	57							E-Test	[71]
United States	2011	686	30	2	42	0	19			E-Test	[72]
										ADM
Senegal	2013	108	1	0	85	0	15			E-test	[73]
										DDM
Nigeria	2009	186		66	95	100				E-test	[74]
Gambia	2012	64	0		68.8					ADM	[75]
Tunisia	2010	273	15.4	0	51.3					E-test	[76]
South Africa	2010	200		97.5						ADM	[77]
										DDM
	2014	1651	6.7		29.4					E-test	[78]
Germany	2013	5296	67.1	0	67.1		24.9			E-test	[79]
	2013	436	7.5	0	32.7		11.7			E-test	[80]
Italy	2012	111	35.2		59.3		22.1			E-test	[81]
	2011	253	9.9							PCR	[82]
England	2009	255						1		E-test DDM	[83]
	2013	343	23.5		33					E-test	[84]
Spain	2011	71	14.7	1.4	45.1	0	14.5			E-test	[85]
	2010	118	35.6							E-test	[86]
	2009	101	54.6		35.7					E-test	[87]
Norway	2012	102	5.9	0	22.5	0				E-test	[88]
Finland	2010	505	8	0	41		7			E-test	[89]
	2013	588	20.1		34.5	2.6				ADM	[90]
Bulgaria	2011	519	17.9		29.5	4				ADM	[91]
	2009	1057	18.7	0.5	21.35	3.15				ADM	[92]
Croatia	2012	382	11.9	0.6	10.1					E-test	[93]
	2014	210					8.1			E-test	[94]
Poland	2013	165	10.9		32.7		1.2			E-test	[95]
	2012	51	22				16			E-test	[96]
	2011	115	34	0	44		5			E-test	[97]
Portugal	2014	180	50	0.6	34.4	0.6	33.9			E-test	[98]
	2011	1115	34.7	0	13.9	0				E-test	[99]
Belgium	2013	189	13.3	0.8	26.1						[100]
	2011	10670	20.3	0	27					ADM	[101]
Netherlands	2014	417	6.14		10.1					E-test	[102]
	2013	746	20.5	0.68	19.9					E-test	[103]
Ireland	2013	85				0	11.7	0		E-test	[104]
	2010	219	13.2		31.5					E-test	[105]
Southern Europe	2014	74	34.7		16.7					E-test	[106]

Amo: Amoxicillin; Cla: Clarithromycin; Met: Metronidazole; Tet: Tetracycline; Lev: Levofloxacin; Rif: Rifabutin; Fur: Furazolidon; DDM: Disk Diffusion Agar; ADM: Agar Dilution Agar.