Lymphocytic colitis: A clue to bacterial etiology

Table 1 Culture media used for the detection of bacterial flora in colonic biopsies

Medium	Temperature	Incubation time (h)	Organism
MacConkey's agar	37 °C	48-72	Coliform bacilli (E coli and Klebsiella) and Proteus
Aerobic blood agar	37 °C	24-48	Staphylococcus aureus
Anaerobic blood agar	37 °C	24-48	Anaerobic bacteria as Bacteroides spp.
Microaerophilic Campy-blood agar	42 °C	24-48	Campylobacter jejuni
MacConkey's selective medium	25 °C	24-48	Yersinia Enterocolitica
Selenite broth enrichment medium and	37 °C	24-48	Salmonella and Shigella
Salmonella-Shigella agar		24

Table 2 Culture results of 60 colonic tissue specimens from 20 patients with lymphocytic colitis

Organism	Patients (n = 20)	RS specimens (n = 20)	SF specimens (n = 20)	HF specimens (n = 20)
E coli	12	12	8	8
E coli + Proteus	2	2	0	0
Proteus	1	1	1	1
Klebsiella	2	2	2	2
Staphylococcus aureus	1	1	1	1
Total number	18	18	12	12

RS: rectosigmoid, SF: splenic flexure, HF: hepatic flexure.

Table 3 Histopathologic data of 60 colonic biopsies from 20 patients with lymphocytic colitis

Feature	RS	SF	HF
1 Surface epithelial damage
1+	8	10	8
2+	6	6	6
3+	6	4	6
2 Crypt distortion
1+	17	16	17
2+	3	4	3
3+	0	0	0
3 LP Inflammation
2+	5	6	2
3+	11	10	12
4+	4	4	6
4 Mean % of IEL	23	22	28

RS: rectosigmoid, SF: splenic flexure, HF: hepatic flexure, LP: lamina propria, IEL: intraepithelial lymphocytes.

Table 4 Correlation between bacteria in tissue sections and histopathologic features in 60 colonic biopsies from 20 patients with lymphocytic colitis

Feature	Bacteria		χ2	P
	+	–
1 Epithelial damage
1+	1	25	9.9	0.007
2+	4	14
3+	7	9
2 Crypt distortion
1+	10	40	0.4	NS
2+	2	8
3+	0	0
3 LP Inflammation
2+	2	11	6.0	0.05
3+	4	29
4+	6	8

LP: lamina propria, NS: not significant.