Clinical and histologic features differentiating non-relapsing colitis from first attacks of inflammatory bowel disease

Histopathological Features in Colonic Biopsies at Diagnosis Predict Long-term Disease Course in Patients with Crohn's Disease

BACKGROUND AND AIMS

Crohn's disease [CD] is characterised by a heterogeneous disease course. Patient stratification at diagnosis using clinical, serological, or genetic markers does not predict disease course sufficiently to facilitate clinical decision making. The current study aimed to investigate the additive predictive value of histopathological features to discriminate between a long-term mild and severe disease course.

METHODS

Diagnostic biopsies from treatment-naïve CD patients with mild or severe disease courses in the first 10 years after diagnosis were reviewed by two gastrointestinal pathologists after developing a standardised form comprising 15 histopathological features. Multivariable logistic regression models were built to identify predictive features and compute receiver operating characteristic [ROC] curves. Models were internally validated using bootstrapping to obtain optimism-corrected performance estimates.

RESULTS

In total, 817 biopsies from 137 patients [64 mild, 73 severe cases] were included. Using clinical baseline characteristics, disease course could only moderately be predicted (area under receiver operating characteristic curve [AUROC]: 0.738 [optimism 0.018], 95% confidence interval [CI] 0.65-0.83, sensitivity 83.6%, specificity 53.1%). When adding histopathological features, in colonic biopsies a combination of [1] basal plasmacytosis, [2] severe lymphocyte infiltration in lamina propria, [3] Paneth cell metaplasia, and [4] absence of ulcers were identified and resulted in significantly better prediction of a severe course (AUROC: 0.883 [optimism 0.033], 95% CI 0.82-0.94, sensitivity 80.4%, specificity 84.2%).

CONCLUSIONS

In this first study investigating the additive predictive value of histopathological features in biopsies at CD diagnosis, we found that certain features of chronic inflammation in colonic biopsies contributed to prediction of a severe disease course, thereby presenting a novel approach to improving stratification and facilitating clinical decision making.

Biopsy interpretation of colonic biopsies when inflammatory bowel disease is excluded

The interpretation of colonic biopsies related to inflammatory conditions can be challenging because the colorectal mucosa has a limited repertoire of morphologic responses to various injurious agents. Only few processes have specific diagnostic features, and many of the various histological patterns reflect severity and duration of the disease. Importantly the correlation with endoscopic and clinical information is often cardinal to arrive at a specific diagnosis in many cases.

Enteric infections and diagnostic testing

PURPOSE OF REVIEW

Gastrointestinal pathogens profoundly affect human health and well being. The provider's ability to render optimal care often highly depends on diagnostic microbiologic support. We aim to provide a clinically pertinent assessment of the current state of our ability to diagnose human gastrointestinal pathogens and describe (and decry) the unsophistication of many current diagnostic methods and strategies.

RECENT FINDINGS

Recent advances involve improved stool polymerase chain reaction assays and application of this technology to a broader panel of pathogens, stool antigen assays, and improved culture techniques, but there is little penetration of such diagnostic advances into clinical practice. Many such techniques remain limited to research or epidemiologic use and are not typically available in the clinical laboratory.

SUMMARY

Multiple clinical and laboratory factors need to be considered when attempting to diagnose the wide variety of gastrointestinal pathogens afflicting humans. Careful interpretation of diagnostic tests with attention to the population studied and the characteristics of each test is necessary.

[Carcinoid tumor of the ileum and self-limited colitis]

Carcinoid tumors of the ileum represent the most frequent localization of this type of tumor in the gastrointestinal tract. The association of this tumor with the presence of inflammatory bowel disease is well characterized. Self-limiting colitis is an entity that poses serious difficulties when performing a differential diagnosed by other causes of colitis. We present the case of a patient who was diagnosed with carcinoid tumor of the ileum. Clinical and histological findings of self-limiting colitis were also observed.

Escherichia coli O157:H7

E. coli O157:H7 can cause potentially lethal illness in hosts of all ages. These patients often are evaluated and treated by gastroenterologists. The treating physician should administer adequate hydration, usually parenterally, and avoid the use of antibiotics and antimotility agents. The physician needs to notify immediately the appropriate public health authorities of the diagnosis and to ensure that the isolate is recovered by the microbiologist and forwarded for molecular linkage analyses.

The clinical significance of focal active colitis

Focal crypt injury by neutrophils (cryptitis/crypt abscesses), or focal active colitis (FAC), is a common isolated finding in endoscopic colorectal biopsies. Focal active colitis is often thought of as a feature of Crohn's disease, but may also be seen in ischemia, infections, partially treated ulcerative colitis, and as an isolated finding in patients undergoing endoscopy to exclude neoplasia. Clinical, endoscopic, and pathological data were retrospectively reviewed from 49 patients with focal active colitis, who had no other diagnostic findings on colorectal biopsy and no history of chronic inflammatory bowel disease. The histological findings were correlated with clinical diagnoses. Follow-up information was available for 42 of 49 focal active colitis patients. None developed inflammatory bowel disease; however, 19 patients had an acute self-limited colitis-like diarrheal illness, 11 had incidental focal active colitis (patients without diarrhea that were endoscoped to exclude colonic neoplasia and found to have asymptomatic FAC), 6 had irritable bowel syndrome, 4 had antibiotic-associated colitis, and 2 had ischemic colitis. Twenty patients were immunosuppressed, and 19 were taking nonsteroidal anti-inflammatory drugs. No histological features predicted final diagnoses. FAC did not predict the development of chronic colitis, even when mild crypt distortion or slight basal plasmacytosis was present. The preponderance of acute self-limited colitis and antibiotic-associated colitis among the FAC patients, along with the high number of immunosuppressed patients, support the conclusion that most FAC cases are infectious. The incidental detection of FAC in patients undergoing endoscopy to exclude colonic neoplasia was not clinically significant. The role of nonsteroidal anti-inflammatory drugs in FAC deserves further study.

Histological discrimination of idiopathic inflammatory bowel disease from other types of colitis

AIMS

To assess the value of histology in diagnosing inflammatory bowel disease (IBD) in colorectal biopsy specimens.

METHODS

Retrospective, double blind evaluation of colorectal biopsy specimens from 41 patients with colitis (28 with ischaemic colitis and 13 with acute self-limited colitis) and 84 patients with IBD (42 with Crohn's disease and 42 with ulcerative colitis).

RESULTS

The features distinguishing IBD from other forms of colitis included distorted architecture, lymphocyte and plasma cell infiltrate, excess of polymorphonuclear leucocytes, polymorphonuclear cryptitis, crypt abscesses, and basal lymphoid aggregates. The features discriminating between Crohn's disease and ulcerative colitis included an irregular or villous surface, distorted architecture, decrease in mucus content, and polymorphonuclear cryptitis. Using multivariate analysis, 90% of patients with Crohn's disease and 71% of those with ulcerative colitis were correctly classified, the former being strongly defined by epithelioid granulomas, microgranulomas and isolated giant cells, and the latter best defined by an irregular or villous surface, decrease in mucus content and crypt atrophy.

CONCLUSIONS

Examination of colorectal biopsy specimens is a reliable method for diagnosing IBD. In the absence of epithelioid granulomas, microgranulomas and isolated giant cells a diagnosis of Crohn's disease is based on the absence of histological criteria favouring ulcerative colitis. The histological spectrum of indeterminate colitis remains to be clarified.

A prospective study of first attacks of inflammatory bowel disease and infectious colitis. Histologic course during the 1st year after presentation

To investigate the possibilities of differentiating between inflammatory bowel disease (IBD) and infectious colitis on histologic grounds, a prospective histologic study of 105 patients with a first attack of colitis was undertaken. Rectal biopsies were performed on four occasions during 1 year. The strongest predictor of IBD was basal plasmacytosis, followed by more than two vertical crypt branches per medium-power field, crypt distortion, villous mucosa, and mucosal atrophy. These signs were rarely found among patients with infectious colitis. Their frequency increased with the interval between initial symptoms and the first biopsy. To study the development of histologic features in the absence of treatment, the IBD patients were divided into groups depending on this interval. Focal or diffuse basal plasmacytosis increased from 38% in the group with an interval of 1-15 days to 89% in those who presented in 121-300 days, and crypt distortion from 0% to 78%, whereas absence of signs indicating IBD decreased from 62% to 11%. The presence of focal basal plasmacytosis seems to be the earliest sign of IBD. The frequency of histologic signs indicating IBD was maximal (88%) at the 1-week biopsy. After recovery, the basal plasmacytosis and villous mucosa decreased, whereas crypt distortion and mucosal atrophy remained unchanged. Early treatment did not prevent the appearance of any feature.

A prospective study of first attacks of inflammatory bowel disease and infectious colitis. Clinical findings and early diagnosis

In 105 patients with a first attack of colitis, clinical, microbiologic, laboratory, and histologic features were studied prospectively with the aim of differentiating inflammatory bowel disease (IBD) from infectious colitis as early as possible. Of the patients who proved to have IBD the mode of onset of diarrhoeal symptoms was insidious in 56% and non-insidious in 44%, whereas in 81% of those who proved to have infectious colitis the onset was acute. Most patients with infectious colitis presented within 1 week, had early fever, and did not show histologic features characteristic of IBD. Most IBD patients with a more acute onset had clinical warning signs of IBD such as slight previous bowel symptoms, a late presentation time (> 1 week), and absence of early fever or had histologic features characteristic of IBD. These features were basal plasmacytosis, crypt distortion, more than two vertical crypt branches, villous mucosa, mucosal atrophy, epithelioid granuloma, and Paneth cell metaplasia. Moreover, 61% of the IBD patients with a non-insidious onset fell ill in connection with travelling abroad, gastrointestinal infection, or treatment with antibiotics. Knowledge of the above clinical and histologic factors will facilitate differentiation of IBD from infectious-type colitis.

A prospective study of first attacks of inflammatory bowel disease and non-relapsing colitis. Microbiologic findings

In 105 patients with a first attack of colitis, thorough microbiologic investigations of rectal biopsy, faecal, and serum samples were performed with the aims of identifying the colitis-causing agents and shedding light on factors that may precipitate or aggravate the onset of inflammatory bowel disease. Sixty-one patients were found to have inflammatory bowel disease. In 13 (21%) of these patients microbial findings were positive. Eight of the 61 patients fell ill during or immediately after antibiotic treatment, and 10 while travelling abroad. Forty-one of the 105 patients had non-relapsing colitis. In 32 (78%) of these the microbial findings were positive. Six of these 41 patients fell ill during or immediately after antibiotic treatment, and 14 while travelling abroad. Alteration of the intestinal microflora on travelling, gastrointestinal infection, or treatment with antibiotics seems to precipitate or aggravate the symptoms in latent inflammatory bowel disease. In such patients the mode of onset is often changed from insidious to more acute, which may cause difficulty in differentiation from non-relapsing colitis.