Distinct colonoscopy findings of microscopic colitis: Not so microscopic after all?

Table 1 Overview of reports of endoscopic findings/appearance of collagenous colitis

Year	Ref.	No. of cases, gender, age	Endoscopic findings	Lesion locationcollagen table thickness	Clinical associations	Complications
1990	Giardiello et al[15]	1, M, 60	Pseudomembranes	S colon	Watery diarrhea, received NSAIDs/antibiotics	None
				50-70 μm
1993	Richieri et al[16]	1, F, 43	Linear mucosal tears/lacerations	R colon	Watery diarrhea, abdominal pain	None
			Absent vascular mucosal pattern	30-40 μm	Successful therapy with steroids, some bloody stools
			6 mo later; many linear cicatricial lesions
1993	Smiley et al[17]	1, F, 53	Carpet-like patch with nodularity (5 cm)	R colon	Watery diarrhea	None
			Similar to sessile villous adenoma	20-40 μm	Therapy with bulking agents
1995	Katanuma et al[18]	1, F, 72	Diminished vascular pattern	Pancolonic	RA on sulindac, diarrhea and wt loss	None
			Edematous/red mucosa	n/s	Treated by discontinuation of NSAID and salazosulphopyridine
1997	Katsinelos et al[19]	1, M, 65	Multiple red mucosal spots	R colon	Watery diarrhea,	None
			Diminished vascular pattern	n/s	Successful therapy with steroids
1997	Yabe et al[20]	1, F, 47	Multiple red mucosal spots	Pancolonic	6 F/U colonoscopies showed no improvement	None
			Diminished vascular pattern	n/s
1998	Sato et al[21]	1, F, 78	Crowded/tortuous vascular pattern	R + T colon	Watery diarrhea	None
			I/C spray: coarse/nodular surface	n/s
1999	Bermejo et al[22]	1, F, n/s	Pseudomembranes and aphthae	n/s	Watery diarrhea, received NSAIDs/antibiotics	None
				n/s
2001	Freeman et al[23]	1, F, 37	Deep, elliptical mucosal defect/ulcer	S colon	Watery diarrhea, acute abdomen	Perforation
				n/s	Diagnostic laparotomy + IV antibiotics
2001	Yagi et al[24]	1, F, 77	Mucous-covered lesions in R colon	R + T colon	Watery diarrhea, 4 colonoscopy linear lesions in rectum, ASA-associated	None
			Ulcer in descending colon	30-60 μm
			2nd look: rectal pseudomembranes
2002	Cruz-Correa et al[25]	2, F, (73/61)	Deep lacerations/tears	R and T colon	All had hypothyroidism	None
		1, M, 62	0.5-4 cm long (to muscularis mucosa)	n/s	Therapy with tetracycline/5-ASA
2003	Kakar et al[26]	8, F, (a. r: 37-91)	Linear ulcers or lacerations (5)	R colon (5)	Aspirin and NSAID-associated CC	None
		1, M, 27	Diminished vascular pattern (2)	S colon (3)	Treated with discontinuation, bismuth
			Aphthae (2), pseudomembranes (1)	n/s	Mesalamine or azathioprine/6-MP
2003	Sato et al[27]	1, F, 78	1st colonoscopy: 3 mm nodule	Pancolonic	Watery diarrhea, wt loss	None
			2nd look: crowded/tortuous vascular pattern	R: 40-70 μm	ASA-associated
			I/C spray: coarse and nodular, uneven surface	L: 20 μm
2003	Byrne et al[28]	1, F, 27	Erythematous mucosa	S colon	Watery diarrhea,	None
			Multiple pseudomembranes	n/s	common variable immunodeficiency (CVID)
2003	Yuan et al[29]	6, F, (a. r: 54-81)	Linear ulcers (1),	T colon	Pseudomembranes in CC, only endoscopic cases included	None
			R colon ulcers (2), inflamed rectum (1)	n/s
2004	Buchman et al[30]	1, F, 58	Hemorrhagic mucosal spots and erythema, granularity/pseudomembranes	R colon	Prednisolone, antibiotics, TPN, PPI, hypoalbuminemia	None
		1, F, 46
2004	Sherman et al[31]	3, F, (a. r: 66-73)	Mucosal tears and fractures	R + T colon	Watery diarrhea, wt loss, hypoalbuminemia	Perforation in 3/4 cases
		1, M, 69	Granularity of mucosa at places	40-50 μm
2006	Wickbom et al[32]	3, F, (a. r: 73-86)	Mucosal tears and fractures (4-5 cm long)	R + T colon	All on aspirin	None
			Mucosal scars on repeat colonoscopy	14-40 μm	ACE/lansoprazole-induced (1 case)
2006	Koulaouzidis et al[33]	1, F, 83	Mucosal tears	Cecum	Iron deficiency anemia	None
				n/s
2007	Poupardin-Moulin et al[34]	1, F, 80	Longitudinal mucosal fractures	R + T colon	No significant clinical associations, diagnosis missed	None
				n/s
2007	Smith et al[35]	1, F, 43	Long, linear mucosal fractures	R colon	Treated with sulfasalazine	Perforation
				n/s		Hemicolectomy
2007	McDonnell et al[36]	3, n/s, n/s	Bright linear marks/parallel corkscrew lesions: “cat scratch” colon	R colon	n/s	none
				n/s
2008	Allende et al[37]	9, F, (a. r: 44-80)	Mucosal fractures to muscularis propria (7)	R colon (6)	2/12 underwent barium enema	Perforation all cases
		1, M, 71	Ragged mucosal defect (1)	T colon (3)		2 during colonoscopy
			Wall induration (1), constriction (1)	L colon (1)
2008	Umeno et al[38]	7, n/s, (a. r: 37-92)	Longitudinal mucosal defects (ulcers/tears)	L colon	Only in the lansoprazole treated group	None
			Longitudinal scar in one case	12.5-50 μm
2008	Hashimoto et al[39]	1, F, 66	Whirling/circling mucosal vessel network	Pancolonic	SLE, treated with mesalamine	None
			Linear (20 cm) ulcer/scar in the descending	n/s	2nd look: normal vessels, smaller scar
2009	Watanabe et al[40]	1, F, 68	Multiple, longitudinal thin ulcers	L colon	Lansoprazole, discontinued and healed	None
				30 μm
2009	Yusuke et al[41]	1, F, 78	Ragged and linear, long mucosal tear	S colon	Abrupt abdominal pain, PR blood	None
			Hypertrophic scar	n/s	Lansoprazole, discontinued
2009	Cuoco et al[42]	1, F, 68	Deep linear ulcer-type defects	R + L colon	Watery diarrhea, abdominal pain	None
			7 cm long in ascending	n/s	4 L PEG for cleansing
2009	Dunzendorfer et al[43]	1, F, 60	3 cm hypertrophic mucosal scar	S colon	Long history of constipation	None
				n/s	Wt loss, combination therapy
2009	Chiba et al[44]	1, F, 70	Distinct diffuse mucosal cloudiness	Pancolonic	On lansoprazole and loxoprofen,	Reoccurred on a further Lansoprazole course
			Indistinct vascular pattern (UC-like pattern)	n/s	treated with sulfasalazine
2009	Sekioka et al[45]	1, F, 82	2 longitudinal mucosal fractures	T colon	Lansoprazole-associated (6 mo)	Peritonitis, pre-endoscopy
			2nd look: A ridge-type cicatricial lesion	n/s	Treated by discontinuation
2010	Couto et al[46]	1, F, 48	Hemorrhagic mucosal tears	T + L colon	OA on nimesulide and lansoprazole, abdominal pain, wt loss (10%)	None
			Longitudinal white ridges/lines	n/s		Colonoscopy halted at T colon
2010	Sawada et al[47]	1, M, 77	Disappearance of vascular network,	L colon	Lansoprazole-associated (6 years)	None
			Red (numerous) mucosal spots	25 μm	Wt loss, treated by discontinuation collagen table reduced on 2nd look
2010	Koulaouzidis et al[48]	1, M, 83	Fine cicatricial line	L colon	n/s	None
		1, F, 45	Hypertrophic mucosal scar	n/s
2010	van Velden et al[49]	1, F, 63	Linear tears	R + S colon	Instrumentation-induced and insufflation-induced mucosal tears	Perforation
			Diminished vascular pattern and edema	20 μm		Treated conservatively
			2nd look colonoscopy: multiple linear scars
2010	Nomura et al[50]	1, F, 67	Linear mucosal defect x 2,	L colon	Lansoprazole-associated	None
			Linear scar in sigmoid, I/C spray	n/s	Improved on discontinuation	Painful left abdomen
2010	Miyagawa et al[51]	1, M, 81	Longitudinal mucosal defect	L colon	Lansoprazole and hemodialysis	None
				n/s
2010	Milestone et al[52]	3, F; 1, M	Long (5-20 cm) linear ulcers,	S colon	Treated with budesonide and/or bismuth subsalicylate	None
		(a. r: 57-75)	non-hemorrhagic with evidence of healing	n/s
2010	Kawamura et al[53]	3, n/s, n/s	Longitudinal mucosal ulcers	L + S colon	Lansoprazole induced	None
				n/s
2010	Fasoulas et al[54]	1, F , 68	“Cat scratch” colon	R colon	n/s	None
				n/s
2010	Cimmino et al[55]	4, F, (a. r: 24-77)	Mosaic pattern (honeycomb image),	Rectum+ S colon	Case control study	None
			I/C spray: for delineation of pattern	n/s	Mosaic pattern had high LR+/spec

n/s: Not stated; M: Male; F: Female; a. r: Age range; I/C spray: Indigo carmine spray; R colon: Right colon; T colon: Transverse colon; L colon: Left colon; S colon: Sigmoid colon; LR: Likelihood ratio; spec: Specificity; UC: Ulcerative colitis; TPN: Total parenteral nutrition; OA: Osteoarthritis; ASA: Acetyl salicylic acid; wt: Weight; PPI: Proton pump inhibitor; 6-MP: 6-mercaptopurine; PEG: Polyethylene glycol; ACE: angiotensin converting enzyme; NSAIDS: Nonsteroidal antiinflammatory drugs; CC: Collagenous colitis; SLE: Systemic lupus erythematosus; RA: Rheumatoid arthritis.