The endoscopically normal colon: when is mapping biopsy histopathologically justifiable?

Random colonic biopsies in macroscopically normal colonoscopies: is there any benefit? A two-centre audit of current practice

BACKGROUND

Recent guidelines from the British Society of Gastroenterology published in April 2018, recommended performing random colonic biopsies (RCB) in endoscopically normal colonic mucosa when investigating chronic diarrhoea in adults to rule out microscopic colitis; however, cost effectiveness was not accounted for due to poor evidence base. There is now more evidence that RCBs are of low yield and of significant cost.

METHODS

A two-centre audit of current practice was conducted at Rockingham General Hospital and Fremantle Hospital in Western Australia, aiming to determine the yield of RCB in macroscopically normal mucosa for microscopic colitis, from 1 January 2009 to 30 June 2018, with comparisons of practice and results between gastroenterologists and general surgeons. Variability in the indications (diarrhoea and non-diarrhoea indications) for RCBs was determined and the cost of consumables, additional endoscopy time and histopathology analysis were calculated.

RESULTS

A total of 872 normal colonoscopies with RCBs were included; 48.7% of colonoscopies with RCB were for diarrhoea. Only 1.5% of RCBs were positive for microscopic colitis; 3.1% of patients with diarrhoea had microscopic colitis. Only one patient received pharmacologial treatment as a result of the test. The calculated cost per positive diagnosis of microscopic colitis was $10 862.42.

CONCLUSION

RCBs from normal colonic mucosa have poor yield and are costly. Local guidelines should be updated, so RCBs are performed only in patients with a high degree of suspicion of an organic cause of chronic diarrhoea.

Biopsies From Ascending and Descending Colon Are Sufficient for Diagnosis of Microscopic Colitis

BACKGROUND & AIMS

Lymphocytic and collagenous colitis are types of microscopic colitis (MC) that commonly cause chronic watery diarrhea, but there are no macroscopic features of MC that can be detected during colonoscopy. Endoscopists therefore often collect multiple random colonic biopsies, potentially oversampling, increasing times of colonoscopy and slide review. We sought to identify sites from which biopsies could be taken and analyzed to identify patients with MC with a high level of sensitivity and determine the appropriate number of biopsies to take at these sites.

METHODS

We performed a retrospective study using biopsies from 101 consecutive patients with MC (52 cases of collagenous colitis, 42 cases of lymphocytic colitis, 7 combined cases), without comorbidities, from 2017 through 2018. Slides were reviewed, and the proportion of biopsies that were diagnostic of MC were calculated at each biopsy site.

RESULTS

The proportions of biopsy fragments from each site of the colon found to be positive for MC were as follows: cecum, 90.0%; ascending colon, 96.9%; hepatic flexure, 77.8%; transverse colon, 95.7%; splenic flexure, 75.0%; descending colon, 85.0%; sigmoid colon, 90.9%; and rectum, 82.2%. For biopsies labeled random, 95.7% were positive for MC. When findings from ascending and descending colon biopsies were combined, 100% of MC cases were detected.

CONCLUSIONS

MC can be detected with certainty by analyzing biopsies from the ascending and descending colon. Fewer biopsies than were collected from our cases are sufficient for diagnosis. We propose a Western protocol (taking 2 biopsies from each of the ascending and descending colon) in evaluation of patients for MC.

Colon biopsies: benefit or burden?

Analyzing colon biopsies is becoming time consuming and a financial burden as colonoscopy is now the main screening and diagnostic procedure of the main gastrointestinal diseases. Colon sampling can provide important information when used accordingly; otherwise it may only load the medical system unnecessarily. Our aim was to retrospectively analyze criteria for colon biopsies and correlate the diagnostic value of randomly sampling colon, especially in patients with diarrhea. This was a retrospective study on 2109 colonoscopies done over one year. Data was collected from the ENDORAD system and included variables such as: age, gender, quality of preparation, procedure, symptoms, biopsies (type, location), and endoscopy and histology findings. Data was analyzed in a descriptive manner. Out of 496 random biopsies, only 7.4% had positive histology findings. The main symptom was diarrhea and 186 cases of patients complaining of diarrhea with normal colonoscopy had random colon sampling. In 5.3% of these cases histology assessment showed changes of microscopic colitis. Fisher’s test was significant when correlating the odds of having random biopsies in patients with and without diarrhea and patients younger and older than 60. Random sampling of colon during colonoscopies should be done only in selected patients otherwise it has a low diagnostic value.

Ulcerative Colitis Activity Presenting as Fever of Unknown Origin, in a Patient with Longstanding Disease under Continuous Treatment with Mesalazine

Background. The presence of ulcerative colitis (UC) with no bowel symptoms, as fever of unknown origin (FUO), is uncommon. Objective. To describe the case of an 80-year-old woman who presented with fever, with a history of UC under treatment with mesalazine. Case Presentation. She was admitted due to fever lasting for 12 days with no associated symptoms. Seven years earlier, she was diagnosed with UC. After an extended workup for FUO that failed to reach the diagnosis, she underwent a gallium-67 scintigraphy. This revealed a persistent diffuse concentration of gallium-67 in the ascending colon at 24-hour imaging that remained stable at 48- and 72-hour imaging without any topographic change after the use of laxatives. Considering the results and in the absence of another diagnosis, the patient was treated with 30 mg prednisone daily and mesalazine, as treatment of active UC. Subsequently, the patient's condition improved markedly and the fever retreated. One month later, she was reevaluated with a gallium-67 scintigraphy with total absence of gallium-67 concentration in the ascending colon. Conclusion. UC activity must be included in the differential diagnosis of FUO in patients with longstanding disease, since fever may present alone, with no other manifestations.

Importance of biopsies and histological evaluation in patients with chronic diarrhea and normal colonoscopies

BACKGROUND

In patients with chronic diarrhea, colonoscopy may identify inflammatory causes or some occult disease, and also can show a normal mucosa. Serial biopsies of intestinal mucosa can be useful for a differential diagnosis, and to modify the treatment.

AIM

To evaluate whether the biopsies performed in patients with chronic diarrhea and a normal colonoscopy contribute to the differential diagnosis and alter the therapeutic approach.

METHODS

A descriptive, retrospective and cross-sectional study using a computerized database was done. Patients with chronic diarrhea and a normal colonoscopy underwent serial biopsies of the terminal ileum, ascending colon and rectum.

RESULTS

From 398 records, 214 were excluded. Of the 184 patients enrolled, 91 showed histological changes: 40% nonspecific inflammation; 5.18% lymphocytic inflammation, 10.37% eosinophilic inflammation; 39.26% lymphoid hyperplasia; 2.22% collagenous colitis; 2.22% melanosis; and 0.74% pseudomelanose. The sites with the largest number of changes were the terminal ileum and right colon.

CONCLUSIONS

Serial biopsies in patients with chronic diarrhea and normal colonoscopy identified changes in almost 50% of cases and 22% of these cases may had modified the treatment after identification of collagenous, lymphocytic and eosinophilic colitis.

Lower gastrointestinal endoscopy: guidance on indications for biopsy

Lower gastrointestinal endoscopy is a commonly undertaken procedure and has assumed even greater prominence with the inception of the NHS Bowel Cancer Screening Programme (BCSP). Workloads are also constantly increasing within histopathology departments and this has led to a need for workload management by laboratories. Advanced endoscopic techniques now allow for targeted biopsies within settings such as inflammatory bowel disease surveillance and the BCSP. In this article, we provide guidance to the endoscopist for optimal biopsy protocols that are designed to maximise the chance of a subsequent histopathological examination providing definitive results and to reduce the number of unnecessary biopsies, in which histopathology is unlikely to deliver clinically useful information. The majority of the article focuses on biopsy taking within a defined range of clinical situations that are commonly encountered by endoscopists.