Drug Target Insights 2013:7 19–25

doi: 10.4137/DTI.S12109

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R A p I D C o m m u N I C A T I o N

Drug Target Insights 2013:7 19

Microscopic colitis is Associated with several concomitant
Diseases

Bodil Roth1, Jonas manjer2 and Bodil ohlsson1
1Department of Clinical Sciences, Section of Internal medicine. 2Department of Clinical Sciences, plastic Surgery,
Skåne university Hospital, Lund university, Sweden. Corresponding author email: bodil.ohlsson@med.lu.se

Abstract: Microscopic colitis (MC) is a disease with intestinal mucosal inflammation causing diarrhea, affecting predominantly
middle-aged women. The etiology is unknown, but increased prevalence of autoimmune diseases in these patients has been described,
although not compared with controls or adjusted for confounding factors. The aim of this study was to examine the prevalence of com-
mon diseases in patients with MC and controls from the general population. Hypertension, rheumatoid arthritis, asthma or bronchitis,
ischemia, and diabetes mellitus were more prevalent in patients than in controls. The prevalence of gastric ulcer and cancer did not
differ between the groups. Besides corticosteroids, many patients were also being treated with proton pump inhibitors, antidepressant
drugs, angiotensin-converting enzyme inhibitors or angiotensin II receptor antagonists, statins, thyroid hormones, and beta-blockers.
More patients than controls were former or current smokers (72.5% versus 57.7%). Thus, MC patients have an increased prevalence of
several diseases, not only of autoimmune origin.

Keywords: concomitant diseases, drug treatments, microscopic colitis, women

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Roth et al

20 Drug Target Insights 2013:7

Introduction
Primary microscopic colitis (MC) is a clinical and histo-
pathological disease of unknown etiology, characterized
by chronic gastrointestinal symptoms, and a macro-
scopically normal or near normal colonic mucosa. The
entity includes 2 basic forms: collagenous colitis (CC)
and lymphocytic colitis (LC).1 Some studies have shown
a female predominance in both CC and LC,2 mainly
affecting middle-aged women, whereas others have not
been able to confirm this in LC.3,4 Besides primary MC,
a wide array of conditions may lead to secondary lym-
phocytic inflammation in the intestinal mucosa, which
should be distinguished from real MC.1.

An increased prevalence of autoimmune dis-
eases and use of anti-inflammatory drugs has been
described in retrospective studies of patients with
MC. On this basis autoimmunity has been suggested
as an etiology.3,5–7 Asthma has been associated with
LC, but not with CC.8 However, these studies have
not compared the prevalence of diseases in patients
with MC with controls from the general population,
and no adjustment for confounding factors has been
performed. Furthermore, the coexistence of autoim-
mune diseases and MC may be due to a high con-
sumption of anti-inflammatory drugs, rather than a
common causality.3,5–7 Smoking and advanced age are
risk factors for developing MC, and individuals over
65 years of age are at least 5 times more likely to be
diagnosed as having MC than younger individuals.2,9
In these women of upper middle age, it may be difficult
to determine whether the MC is a primary disease, or
a secondary effect due to other concomitant diseases
and drug treatments influencing the colonic mucosa.1

The aim of this cross-sectional study was to com-
pare the prevalence of concomitant diseases in patients
with MC and controls from the same geographic area,
after adjustment for confounding factors.

Materials and Methods
The Ethics Committee of Lund University approved
the study protocol for both patients (Dnr 2009/565
and 2011/209) and controls (Dnr 51-90). All partici-
pants gave their written informed consent to take part
in the study.

Subjects
Women who had been treated for MC at any outpa-
tient clinic of the Departments of Gastroenterology,

Skåne, between 2002 and 2010, were identified by a
search for the ICD-10 classification for the 2 forms
CC and LC (K52.8) in outpatient records, as well as
in the local register at the Department of Pathology,
Skåne University Hospital, Malmö. About 1/3 of the
total number of identified patients were excluded
because they were over 73 years of age, since they
had many other concomitant diseases and drug thera-
pies, obscuring the picture as to whether they were
suffering from primary or secondary MC.1 Of the
patients recognized, only the 240 patients (median
63 years, range 22–73 years) who had the diagno-
ses verified by examination of colonic biopsies by
a pathologist specialized in gastrointestinal pathol-
ogy were invited to participate in the present study.
Altogether, 159 (median 63 years, range 22–73 years)
of the 240 patients invited accepted and were enrolled
in the study. One patient was excluded due to another
IBD diagnosis a few weeks after inclusion, leaving
158 patients (66%), and of these, 133 also agreed to
provide blood samples. These patients represent the
majority of female cases of diagnosed MC in the
southernmost districts of Sweden under the age of
73 years.

Microscopic colitis is more frequent in women
than in men, the small male cohort in our region being
unsuitable for statistical calculations. Furthermore, as
the quality of life and experience of symptoms dif-
fer between the genders,2 we chose to include only
women in the study.

Controls
The malmö Diet and Cancer Study (mDCS)
The MDCS, a population-based prospective cohort
study, invited all women in Malmö born 1923–1950.
Recruitment was carried out between 1991 and 1996,
and 41% of eligible subjects participated. In all,
17,035 women completed the baseline examination.10
The MDCS baseline examination included a dietary
assessment, a self-administered questionnaire about
marital status, education, employment, smoking
habits, wine consumption, physical activity, medi-
cal conditions and medication, anthropometric mea-
surements, and the collection of blood samples.11
Menopausal status was defined using informa-
tion on previous surgery and menstrual status. The
classification of pre-, peri- and postmenopausal
women has been described in detail elsewhere.12

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mC and concomitant diseases

Drug Target Insights 2013:7 21

Women selected as controls in a previous study
on breast cancer were used in the present study as
controls. In all, 737 subjects (median age 56 years,
range 45–73 years) were available and the only
exclusion criterion was that they should not have had
a previous breast cancer at baseline.13

patient recruitment and study design
Between March and June 2011, invitations includ-
ing study information and the same self-administered
questionnaire as was sent to the controls were sent by
mail to all 240 women with MC. In addition, ques-
tionnaires about gastrointestinal symptoms, psycho-
logical well-being and Rome III criteria were sent.
The patients were also invited to visit the outpatient
clinics of the Departments of Gastroenterology, Skåne
University Hospital, Malmö or the Central Hospital
in Kristianstad, to provide blood samples. A remind-
ing letter was sent a month after the invitation letter
to those who had not answered. Questionnaires were
completed 1–3 weeks before blood samples were
collected. Medical records were scrutinized, and age,
gastrointestinal symptoms, examinations, and treat-
ments were recorded, as well as whether the patients
had had a single attack of MC, or had persistent
disease.

Patients were compared with controls from the
MDSC study.

Questionnaire
A self-administered questionnaire about marital
status, education, employment, smoking habits, wine
consumption, medical conditions and medication
was completed by both controls and patients. One of
the questions was: “Have you ever been treated for
any of the following diseases, namely, hypertension,
rheumatoid arthritis, asthma or chronic bronchitis,
gastric ulcer, ischemia including myocardial infarc-
tion, intermittent claudication and stroke, cancer, or
diabetes mellitus?”.

Statistical analyses
The data were analyzed using the statistical software
package SPSS for Windows© (Release 20.0; IBM,
NY, USA). The patients were significantly older,
with a wider age range than controls. Therefore,
the 12 patients younger and the two patients older
than the controls were excluded, as were patients

with celiac disease and gastroenteritis (13 patients),
leaving 131 of the original 158 patients for statisti-
cal analysis. Thus, both controls and patients were
within the age range 45–73 years. First, the distribu-
tion of continuous variables (age, disease duration,
days of drinking wine/month) was tested using a one-
sample Kolmogorov-Smirnov test. All these distribu-
tions differed significantly (P , 0.05) from a normal
distribution. Therefore, the factors studied were cat-
egorized and values were given as median (inter-
quartile range). There was no difference between CC
and LC for any characteristics in this MC cohort14 and
therefore all calculations were performed independent
of the category CC or LC. The number of patients in
the study cohort (131 patients) who were under treat-
ment with a drug was given as the percentage of drug
users. Differences between groups were calculated by
the 2-tailed Mann–Whitney U test. Fisher’s exact test
was used for categorical variables. P-values , 0.05
were considered statistically significant.

Age was divided into 5-year intervals. The cohort
was divided into quartiles of the number of days
wine was taken per month. Smoking was divided
into 3 categories: subjects who had never smoked,
subjects who had stopped smoking, and current
smokers, including both regular and occasional
smokers. Employment was divided into 3 categories:
employed, retired, or others, where others included
housewives, students, and unemployed. Education
was divided into patients with or without a university
education. Some answers concerning days of drink-
ing wine/month and level of education were lacking.
These were labeled as separate categories. Factors
intended to be studied (independent variables) were
initially examined using univariate analyses to calcu-
late odds ratios with 95% confidence intervals (OR
with 95% CI). Analyses were then adjusted for age
at baseline, smoking, the number of days of drinking
wine/month, level of education, and employment, as
these characteristics differed by .5 percentage points
between controls and patients.

Results
patient characteristics
In total, 131 women (median age 63 (59–67) years)
with MC were included in the statistical calcula-
tions (Table 1). Collagenous colitis was diagnosed in
82 patients (62.6%) and LC in 49 patients (37.4%).

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Roth et al

22 Drug Target Insights 2013:7

Table 1. patient and control characteristics.

controls
n = 737

Microscopic
colitis
n = 131

Age at study (years) 56.16
(50.47–62.36)

63.00
(58.94–67.15)

Age groups (%)
45–49 17.1 4.6
50–54 22.3 6.9
55–59 22.3 13.7
60–64 19.5 32.1
65–69 11.7 26.0
70–74 7.2 16.8
Smoking habits (%)
Never smoked 42.3 27.5
Stopped smoking 29.9 36.6
Current smokers 27.8 35.9
Days of drinking
wine/month (%)
missing data 6.8 5.3
0–2 49.5 42.7
3–4 15.2 12.2
5–7 12.3 8.4
.7 16.1 31.3
married women (%) 61.9 58.0
Level of education (%)
missing 0 2.3
#12 years at school 76.1 67.9
.12 years at school 23.9 29.8
Employment (%)
Employed 65.7 44.3
Retired 26.5 49.6
others* 7.9 6.1

notes: *Includes housewives, students and unemployed. Values are
given as median (interquartile range).

The duration of the disease was 7 (3–14) years.
Measurements of hemoglobin (Hb) in blood and
C- reactive protein (CRP) in plasma were in the major-
ity of patients within reference values, showing that
the patients were in an overall inactive phase (data not
shown). Of the patients, 91.7% were born in Sweden
compared with 90.2% of the controls. More patients
than controls had completed a University degree
(P = 0.001). As the patients were older than the con-
trols, more patients were retired (P , 0.001) (Table 1).

Smoking and drinking habits
There were more controls than patients who had never
smoked, and the prevalence of both current and for-
mer smokers was higher among the patients (Table 1).
More patients than controls drank wine .7 days a
month (Table 1).

Concomitant diseases
The presence of any concomitant disease was more
prevalent in patients with MC (58.8%) than in controls
(35.5%) (adjusted OR = 1.81, 95% CI = 1.18–2.81).
Hypertension was present in more than 1/3 of the
patients. Rheumatoid arthritis was 6 times more com-
mon and asthma and bronchitis 3 times as common
in patients as in controls (Table 2). The type of dia-
betes mellitus is not known in controls, but 2 of the
patients with MC had type 1 diabetes and 7 had type 2
diabetes. There was no difference between those who
had had a single attack of MC or a persistent MC in
those with concomitant diseases and those without
(P = 0.930). There was no difference in duration of
MC, or age at inclusion, between those with concom-
itant diseases and those without in addition to the MC
(P = 0.564 and P = 0.146, respectively).

The patients were currently being treated with sev-
eral drugs at the time of inclusion. The most common
drug treatments as a percentage of the study cohort
were corticosteroids (32.1%), proton pump inhibitors
(26.0%), antidepressant drugs, specifically selective
serotonin reuptake inhibitors (21.4%), angiotensin-
converting enzyme inhibitors or angiotensin II
receptor antagonists (18.3%), statins (17.6%), thy-
roid hormones (17.6%), and beta-blockers (16.0%).
Patients on any of these drug treatments were older
at inclusion (64.92 (60.00–68.34) years and 62.07
(55.55–64.24) years, respectively, P = 0.012). Those
who had persistent MC had a higher prevalence of
current drug treatment (P = 0.024). 8 of the 31 patients
with rheumatoid arthritis used non-steroidal anti-
inflammatory drugs as well as many other drugs.
There was no difference in the prevalence of CC and
LC in patients who were on any of these drugs or
had any of the concomitant diseases (P = 1.000 and
P = 0.931, respectively).

Discussion
In spite of excluding all those over 73 years of age,
to get a fairly healthy group with real MC, several
concomitant diseases and drugs were still present.
All chronic diseases measured were over-represented
in patients, in contrast to a history of gastric ulcer or
cancer.

Previous studies have been retrospective, col-
lecting patient cohorts seen at tertiary centers.5–7 In
our present study, we used a cross-sectional design,

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mC and concomitant diseases

Drug Target Insights 2013:7 23

collecting patients from the whole region at pri-
mary, secondary and tertiary centers. This approach
reflects the patient group in a better way, as patients
handled at tertiary centers are often selected cases.15
As patients with MC are women of upper middle age
with former or current smoking in the anamnesis, it
is to be expected that asthma, bronchitis, and car-
diovascular diseases will be frequently seen in such
a cohort, apart from diseases of autoimmune origin.
In the present study, hypertension was the most
common concomitant disease, and recent research
confirms that smokers have a higher prevalence of
hypertension than non-smokers.16 A high prevalence
of cardiovascular diseases in patients with MC has
been described previously, but this was not compared
with a control population.17

The medication of the controls is not reported
here because drug recommendations have been

Table 2. The prevalence of different diseases in microscopic colitis (mC) and controls.

controls
n = 737

Mc
n = 131

crude
OR 95% cI

OR 95% cI

Hypertension (%)
missing 8.4 1.5 – –
No hypertension 77.7 62.6 1.00 1.00
Hypertension 13.8 35.9 3.22 (2.12–4.88) 2.73 (1.49–3.78)
Rheumatoid arthritis (%)
missing 8.4 1.5 – –
No rheumatoid arthritis 87.9 74.0 1.00 1.00
Rheumatoid arthritis 3.7 23.7 7.67 (4.39–13.40) 7.21 (3.81–13.64)
Asthma and bronchitis (%)
missing 8.4 1.5 – –
No asthma 85.5 80.9 1.00 1.00
Asthma 6.0 16.8 2.97 (1.71–5.16) 3.18 (1.68–6.00)
Cancer (%)
missing 8.4 1.5 – –
No cancer 85.9 89.3 1.00 1.00
Cancer 5.7 8.4 1.42 (0.71–2.83) 1.14 (0.53–2.47)
Diabetes mellitus (%)
missing 8.4 1.5 – –
No diabetes mellitus 90.5 90.8 1.00 1.00
Diabetes mellitus 1.1 6.9 6.31 (2.38–16.67) 4.91 (1.62–14.87)
Gastric ulcer (%)
missing 8.4 1.5 – –
No gastric ulcer 84.3 80.9 1.00 1.00
Gastric ulcer 7.3 16.8 2.39 (1.40–4.08) 1.77 (0.95–3.30)
Ischemia* (%)
missing 8.4 1.5 – –
No ischemia 88.7 88.5 1.00 1.00
Ischemia 2.8 9.9 3.49 (1.70–7.16) 2.96 (1.30–6.76)

notes: *Including myocardial infarction, intermittent claudication and stroke. Analyses were performed adjusted for age at baseline, smoking, days of
drinking wine/month, level of education, and employment, as these characteristics differed by .5 percentage between controls and patients.
Abbreviations: OR, Odds ratio; CI, Confidence interval.

changed since the control cohort was recruited.
However, medication in controls should be less than
of the patients as they were healthier. In accordance
with previous reports,18 the present patients who were
taking drugs were older than un-treated ones. It has
been suggested in previous studies that the drugs
being consumed extensively by the patient group are
associated with MC and could explain the persistent
character of the disease.6,18–20 The consensus is that
drugs suspected to induce MC should be withdrawn
prior to diagnosis, and that the introduction of treat-
ment against MC may not be followed in the daily
clinic.2 This could contribute to the high prevalence
figures of MC in the growing elderly population, with
more efficient treatment regimens for cardiovascular
diseases.2 Prospective studies are needed to determine
whether the introduction of a new drug precedes the
development of the disease, and whether the disease

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Roth et al

24 Drug Target Insights 2013:7

remains resolved after drug withdrawal, in order to
estimate appropriate prevalence figures of MC.

Ischemic colitis is another frequently diagnosed
condition in elderly patients with a history of smok-
ing, cardiovascular diseases and diabetes mellitus,
and in those who are on vasoactive drugs.21 These
characteristics are similar to those described for the
MC population.2,3,5 Corticosteroids are used in the
treatment of MC, with a better response than anti-
inflammatory drugs, and corticosteroids can also be
useful in the treatment of ischemic, radiatic, and toxic
colitis.2,21–23

There are several limitations in this study. One is
the use of an external control group, and that recom-
mendations for drug prescription have been changed
since our recruitment of controls. It is very difficult
to recruit healthy volunteers to clinical studies. The
response rate of our control group was 41%, and
it is possible that these subjects are healthier than
those who did not agree to participate. However, it
is a strength of the study to, for the first time, com-
pare patients with MC to such a well-defined control
group.13 Furthermore, the data concerning smoking,
overweight status, and level of education were similar
in this control group to a study with 80% participation
from the same population.10 We could not find from
the medical records whether MC was developed prior
to or after the introduction of new drugs, and there-
fore it is impossible to determine whether the disease
is primary or secondary. An additional strength of the
study was that the control group is derived from the
same geographic area as the patient group, and that
calculations are adjusted for age differences, life style
factors, and socioeconomic factors.

In conclusion, patients with a diagnosis of MC
are a selection of middle-aged women, former or
current smokers, with several concomitant diseases
and cardiovascular ageing, and therefore are under
treatment with a wide range of diverse drugs. It is
not surprising that these patients exhibit gastrointes-
tinal symptoms and microscopic, intestinal, mucosal
inflammation. These changes must be interpreted
with caution, before considering them as a separate
entity of autoimmune origin, instead of secondary
reactions to ischemia and toxic stimulants. Efforts
must be made to better classify and diagnose patients
with real, primary MC, to avoid over- prescription of
corticosteroids.

Author contributions
Conceived and designed the experiments: BR, JM,
BO. Analyzed the data: BO. Wrote the first draft
of the manuscript: BO. Contributed to the writing
of the manuscript: BR, JM, BO. Agree with manu-
script results and conclusions: BR, JM, BO. Jointly
developed the structure and arguments for the paper:
BR, JM, BO. Made critical revisions and approved
final version: BR, JM, BO. All authors reviewed and
approved of the final manuscript.

Funding
This study was sponsored by grants from the Bengt
Ihre Foundation and the Development Foundation of
Region Skåne.

competing Interests
Authors disclose no potential conflicts of interest.

Disclosures and ethics
As a requirement of publication the authors have pro-
vided signed confirmation of their compliance with
ethical and legal obligations including but not lim-
ited to compliance with ICMJE authorship and com-
peting interests guidelines, that the article is neither
under consideration for publication nor published
elsewhere, of their compliance with legal and ethi-
cal guidelines concerning human and animal research
participants (if applicable), and that permission has
been obtained for reproduction of any copyrighted
material. This article was subject to blind, indepen-
dent, expert peer review. The reviewers reported no
competing interests.

References
1. Carmack SW, Lash RH, Gulizia JM, Genta RM. Lymphocytic disorders of

the gastrointestinal tract: a review for the practicing pathologist. Adv Anat
Pathol. 2009;16(5):290–306.

2. Pardi DS, Kelly CP. Microscopic colitis. Gastroenterology. 2011;140(4):
1155–65.

3. Olesen M, Eriksson S, Bohr J, Järnerot G, Tysk C. Lymphocytic colitis:
a retrospective clinical study of 199 Swedish patients. Gut. 2004;53(4):536–41.

4. Fernández-Bañares F, Salas A, Forné M, Esteve M, Espinós J, Viver JM.
Incidence of collagenous and lymphocytic colitis: a 5-year population-based
study. Am J Gastroenterol. 1999;94(2):418–23.

5. Bohr J, Tysk C, Eriksson S, Abrahamsson H, Järnerot G. Collagenous colitis: a
retrospective study of clinical presentation and treatment in 163 patients. Gut.
1996;39(6):846–51.

6. Pardi DS, Ramnath VR, Loftus EV, Tremaine WJ, Sandborn WJ. Lymphocytic
colitis: clinical features, treatment, and outcomes. Am J Gastroenterol.
2002;97:2829–33.

7. Chande N, Driman DK, Reynolds RP. Collagenous colitis and lymphocytic
colitis: patient characteristics and clinical presentation. Scand J Gastroenterol.
2005;40(3):343–7.

http://www.la-press.com

mC and concomitant diseases

Drug Target Insights 2013:7 25

8. Koskela RM, Niemelä SE, Karttunen TJ, Lehtola JK. Clinical charac-
teristics of collagenous and lymphocytic colitis. Scand J Gastroenterol.
2004;39(9):837–45.

9. Yen EF, Pokhrel B, Du H, et al. Current and past cigarette smoking sig-
nificantly increase risk for microscopic colitis. Inflamm Bowel Dis.
2012;18(10):1835–41.

10. Manjer J, Carlsson S, Elmståhl S, et al. The Malmö Diet and Cancer Study:
representativity, cancer incidence and mortality in participants and non-
participants. Eur J Cancer Prev. 2001;10(6):489–99.

11. Manjer J, Elmståhl S, Janzon L, Berglund G. Invitation to a population-
based cohort study: differences between subjects recruited using various
strategies. Scand J Public Health. 2002;30(2):103–12.

12. Manjer J, Johansson R, Berglund G, et al. Postmenopausal breast cancer
risk in relation to sex steroid hormones, prolactin and SHBG (Sweden).
Cancer Causes Control. 2003;14(7):599–607.

13. Almquist M, Bondeson AG, Bondeson L, Malm J, Manjer J. Serum levels
of vitamin D, PTH and calcium and breast cancer risk-a prospective nested
case-control study. Int J Cancer. 2010;127(9):2159–68.

14. Roth B, Gustafsson RJ, Ohlsson B. Auto-antibodies and their association
with clinical findings in women diagnosed with microscopic colitis. PLoS
One. 2013;8(6):e66088.

15. Zankel E, Rogler G, Andus T, Reng CM, Schölmerich J, Timmer A. Crohn’s
disease patient characteristics in a tertiary referral center: comparison with
patients from a population-based cohort. Eur J Gastroenterol Hepatol.
2005;17(4):395–401.

16. D’Elia L, De Palma D, Rossi G, et al. Not smoking is associated with lower
risk of hypertension: results of the Olivetti Heart Study. Eur J Public Health.
2013.

17. Bjørnbak C, Engel PJ, Nielsen PL, Munck LK. Microscopic colitis: clini-
cal findings, topography and persistence of histopathological subgroups.
Aliment Pharmacol Ther. 2011;34(10):1225–34.

18. Rasmussen MA, Munck LK. Systematic review: are lymphocytic colitis and
collagenous colitis two subtypes of the same disease—microscopic colitis?
Aliment Pharmacol Ther. 2012;36(2):79–90.

19. Cindoruk M, Tuncer C, Dursun A, et al. Increased colonic intraepithelial
lymphocytes in patients with Hashimoto’s thyroiditis. J Clin Gastroenterol.
2002;34(3):237–9.

20. Beaugerie L, Pardi DS. Review article: drug-induced microscopic
colitis—proposal for a scoring system and review of the literature. Aliment
Pharmacol Ther. 2005;22(4):277–84.

21. O’Neill S, Yalamarthi S. Systematic review of the management of ischaemic
colitis. Colorectal Dis. 2012;14(11):e751–63.

22. Kochhar R, Patel F, Dhar A, et al. Radiation-induced proctosigmoiditis.
Prospective, randomized, double-blind controlled trial of oral sulfasalazine
plus rectal steroids versus rectal sucralfate. Dig Dis Sci. 1991;36(1):103–7.

23. Onishi H, Oosegi T, Machida Y. Efficacy and toxicity of Eudragit-coated
chitosan-succinyl-prednisolone conjugate microspheres using rats with
2,4,6-trinitrobenzenesulfonic acid-induced colitis. Int J Pharm. 2008;
358(1–2):296–302.

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