Differentiating Crohn’s disease from intestinal tuberculosis

Table 1 Rates of smear and culture positivity for Mycobacterium tuberculosis in patients with intestinal tuberculosis

Ref.	Area	Number of patients	AFB smear positivity	AFB culture positivity	Type of culture
Patel et al[38], 2004	India	173	29%	19%	Solid
Amarapurkar et al[11], 2008	India	26	23%		Bactec
Ramadass et al[42], 2010	India	24		45.8%	Bactec
Dutta et al[15], 2011	India	24	37.5%	-	-
Ye et al[39], 2012	South Korea	329	17%	44.1%	Both
Lei et al[18], 2013	China	88	10.8%	-	-
Sekine et al[40], 2015	Japan	50	32%	50%	Bactec
Jung et al[20], 2016	South Korea	98	16	17	-
Kumar et al[41], 2017	India	37	2.7%	2.7% (LJ medium)	Both
				8.1% (Gene-Xpert)
Bae et al[22], 2017	South Korea	40	10%	70%	Bactec

AFB: Acid-fast bacillus.

Table 2 Comparison of clinical features between Crohn’s disease and intestinal tuberculosis

Author/ year	Makharia et al[7], 2010		Li et al[17], 2011		Lei et al[18], 2013		Kedia et al[19], 2015		Jung et al[20], 2016		Yadav et al[21], 2017		Overall
Country	India		India		China		India		South Korea		India
Number of patients	CD	ITB	CD	ITB	CD	ITB	CD	ITB	CD	ITB	CD	ITB	CD	ITB
	53	53	130	122	103	88	54	50	158	98	88	69
Diarrhoea	85	37	66	47	63	57	69	18	68	20	43	16	43-85	16-57
Hemato-chezia	68	17	32	7	24	20	32	12	29	14	28	9	24-68	7-20
Constipation	8	49	4	13			10	26	4	5	-	-	4-10	5-49
Anorexia	-	-	-	-			57	78	-	-	-	-	57	78
Abdominal pain	70	91	86	81			78	94	82	61	80	90	70-86	61-94
Intestinal obstruction	26	55	29	10	21	11	26	48	-	-	31	51	21-31	10-55
Abdominal mass	-	-	-	-			0	0	3	1	53	60	-	-
Fever	28	42	30	43	24	34	30	38	25	13	23	37	23-30	13-43
Weight loss	55	83	72	76	48	60	93	90	31	15	66	75	31-93	15-90
Perianal disease	30	8	16	4			-	-	32	0	-	-	16-32	0-8
Night sweats			20	31			-	-	1	7	-	-	1-20	7-31
EIMs	45	13	11	2	29	9	-	-			-	-	11-45	2-13

All figures are percentages. Last column summarizes all the studies. CD: Crohn’s disease; ITB: Intestinal tuberculosis; EIMs: Extra-intestinal manifestations.

Table 3 Comparison of different sites of involvement on colonoscopy between patients with Crohn’s disease and intestinal tuberculosis

Author/ year	Makharia et al[7], 2010		Li et al[17], 2011		Yu et al[8], 2012		Jung et al[20], 2016		Overall
Country	India		China		China		South Korea
Number of patients	CD	ITB	CD	ITB	CD	ITB	CD	ITB	CD	ITB
	53	53	130	122	53	43	158	98
Rectum	62	19	39	16	28	28	40	7	28-62	7-28
Sigmoid colon	66	11	45	23	40	37	53	7	40-66	7-37
Descending colon	60	13	34	25	34	35	44	9	34-60	9-35
Transverse colon	-	-	40	33	36	51	54	28	36-54	28-51
Ascending colon	64	43	46	62	59	63	65	61	46-65	43-63
Caecum	89	92	43	57	48	59	56	48	43-89	48-92
IC valve	-	-	55	75	82	82	-	-	55-82	75-82
Ileum	25	15	66	60	73	88	76	64	25-76	15-88

All figures are percentages. Last column summarizes all the studies. CD: Crohn’s disease; ITB: Intestinal tuberculosis.

Table 4 Comparison of colonoscopic findings between patients with Crohn’s disease and intestinal tuberculosis

Author/ year	Lee et al[9], 2005		Makharia et al[7], 2010		Li et al[17], 2011		Yu et al[8], 2012		Jung et al[20], 2016		Bae et al[23], 2017		Overall
Country	South Korea		India		India		China		South Korea		South Korea
Number of patients	CD	ITB	CD	ITB	CD	ITB	CD	ITB	CD	ITB	CD	ITB	CD	ITB
	44	44	53	53	130	122	53	43	158	98	40	40
Longitudinal ulcers	41	2	30	8	55	8	57	7	63	7	55	0	30-63	0-8
Transverse ulcers	25	66	-	-	5	41	34	70	14	73	8	63	5-34	41-73
Aphthous ulcers	82	21	55	13	54	44	13	14	60	21	43	10	13-82	10-44
Pseudopolyp	27	52	-	-	33	44	62	33	33	18	35	78	27-62	18-78
Cobblestone	34	7	17	0	28	2	25	5	40	10	33	3	17-40	0-10
Nodularity	-	-	25	49	49	33	-	-	-	-	-	-	25-49	33-49
Patulous valve	9	40	-	-	12	51	2	26	9	21	0	43	0-12	21-51
Stricture	21	18	-	-	29	23	-	-	28	9	-	-	21-29	9-23
Skip lesions	82	18	66	17	-	-	66	58	-	-	-	-	66-82	17-58

All figures are percentages. Last column summarizes all the studies. CD: Crohn’s disease; ITB: Intestinal tuberculosis.

Table 5 Comparison of pathologic findings between Crohn’s disease and intestinal tuberculosis

	Gan et al[27], 2002		Pulimood et al[28], 2005		Kirsch et al[30], 2006		Jin et al[31], 2010		Makharia et al[7], 2010		Yu et al[8], 2012		Ye et al[32], 2015		Jung et al[20], 2016		Overall
Diagnosis	TB	CD	TB	CD	TB	CD	TB	CD	TB	CD	TB	CD	TB	CD	TB	CD	TB	CD
Number of patients	39	30	33	31	18	25	52	26	53	53	53	40	16	52	98	158
Granulomas	54	30							62	53	70	22	81	67	67	54	54-81	22-67
Caseous necrosis	18	0	36	0	22	0	27	0	13	2	13	0			39	0	13-40	0
Confluent granulomas	-	-	42	3	50	0	46	8	-	-	40	3	39	6	-	-	39-60	0-6
5 granulomas/biopsy site	-	-	45	0	44	24	-	-	22	4	20	0	-	-	-	-	40-44	0-24
10 granulomas/biopsy site	-	-	-	-	33	0	-	-	-	-	-	-	-	-	-	-	33	0
Large granulomas	-	-	51	0	67	8	75	19	27	9	43	0	54	11	-	-	27-90	0-27
Microgranuloma	-	-							41	43	-	-			-	-	41	43
Submucosal granulomas	-	-	39	6	44	12	-	-	21	8	-	-	69	54	-	-	21-69	5-54
Ulcers lined by bands of Epithelioid histiocytes	-	-	61	0	61	8	-	-	23	8	-	-	-	-	-	-	23-61	0-8
Disproportionate submucosal Inflammation	-	-	-	-	67	10	-	-	34	17	74	84	-	-	-	-	34-74	5-84
Architectural distortion distant to granulomatous inflammation	-	-	0	62	-	-	-	-	-	-	-	-	81	90	-	-	0-81	62-90
Focal enhanced colitis	-	-	-	-	-	-	-	-	36	68	-	-	-	-	-	-	38	68

All figures are percentages. Last column summarizes all the studies. CD: Crohn’s disease; ITB: Intestinal tuberculosis.

Table 6 Features included and the diagnostic accuracy of different multi-parametric predictive models for differentiating Crohn’s disease and intestinal tuberculosis

Parameters	Makharia 2010[7]		Li 2011[17]		Yu 2012[8]		Jung 2016[20]		Bae 2017[23]
Number of patients	CD	ITB	CD	ITB	CD	ITB	CD	ITB	CD	ITB
	53	53	130	122	53	43	162	99	40	40
Clinical	Bleeding PR Weight loss		Bleeding PR Surgery history Perianal disease		Night sweats		Age Gender Diarrhea		-
Endoscopic	Sigmoid colon involvement		Longitudinal ulcer Cobblestone appearance Transverse ulcer Rodent ulcer Rectal involvement Fixed open IC valve		Longitudinal ulcer		Transverse ulcer Longitudinal ulcer Sigmoid Colon involvement		Anorectal lesions Longitudinal ulcers Aphthous ulcers Cobblestone appearance Involvement < 4 segments Patulous IC valve Transverse ulcers Pseudopolyps
Pathologic	Focal enhanced colitis				Granuloma		-		-
Radiologic	-		PTB Ascites		-		Suspicious PTB		Proximal intestine PTB
Laboratory	-		Positive Mantoux		-		-		Positive ASCA Positive IGRA
AUROC	0.91		0.83		0.86		0.98		0.96
Sensitivity	83%		83%		67%		98%		95%
Specificity	79%		82%		93%		92%		97%

ASCA: Anti-saccharomyces cerevisiae antibody; CD: Crohn’s disease; IGRA: Interferon gamma release assays; ITB: Intestinal tuberculosis.