Radiographic stool quantification: an equivalence study of 484 symptomatic and asymptomatic subjects

Meta-analysis: Intestinal ultrasound to evaluate colonic contents and constipation

BACKGROUND

Constipation can be diagnosed clinically using the Rome criteria. Ultrasound (US), which lacks the radiation exposure of conventional X-ray, holds promise as a non-invasive tool to evaluate colonic contents and constipation.

AIM

To examine the role of US in the assessment of constipation.

METHODS

We performed a systematic search of Embase (OVID, 1984), Medline (Ovid, 1946), Cochrane Central, ClinicalTrials.gov and Australia New Zealand Clinical Trials Registry from database inception to 26 January 2024 according to PRISMA guidelines and prospectively registered with PROSPERO. All studies using US to assess constipation or colonic contents in either adults or children were included. Rectal diameter measurements were pooled in meta-analysis. Risk of bias was assessed using the Newcastle Ottawa Scales and Joanna Briggs Institute checklists.

RESULTS

Of 12,232 studies screened, 51 articles (6084 patients; 3422 children) describing US to assess symptoms in patients with constipation were included. Most studies used Rome criteria to diagnose constipation. Rectal diameter was associated with clinical constipation in 29 paediatric studies (3331 patients). Meta-analysis showed the mean rectal diameter of constipated patients was significantly higher than controls (mean difference 12 mm, 95% confidence intervals (CI): 6.48, 17.93, p < 0.0001, n = 16 studies). Other features of constipation on US included posterior acoustic shadowing and echogenicity of luminal contents.

CONCLUSION

US is an appealing imaging modality to assess luminal contents and constipation. Further well-designed studies are required to validate US metrics that accurately identify constipation.

Analyzing fecal loading and retention patterns by abdominal X-rays of hospitalized older adults: A retrospective study

Background

Aging may affect ascending colon (AC) differently from descending colon (DC) and increase the risk of fecal loading (FL) in AC.

Methods

Patients aged ≥65 years admitted to a community hospital were analyzed by abdominal x‐ray for fecal loads and stool retention patterns. FL was scored between 0 and 5 (severe) on each segment of colon with a possible total score 20. Mean segment scores ≥3.5 were designated as high scores for both AC and DC. Logistic regression was performed between groups to identify factors associated with FL patterns.

Results

Groups identified were high FL in both AC and DC (N = 21, 17.2%), FL predominantly in AC (N = 38, 31.1%), low FL in both AC and DC (N=60, 49.2%), and FL low in AC and high in DC (N = 3, 2.5%). Among 71 patients with total FL scores ≥13 (indicating significant stool retention), 37 (52.1%) had the FL predominantly in AC. Patients prescribed antibiotic(s) prior to hospitalization had lower odds of FL predominantly in AC (adjusted odds ratio = 0.18, 95% confidence interval = 0.04–0.84) compared to the group of low FL in both AC and DC with the adjustment of confounders.

Conclusion

This study found that 52.1% of those with significant stool retention on x‐ray had the FL predominantly in AC. Antibiotic use was associated with lower odds of having FL predominately in AC. This study provided insights of FL distribution in colon and AC could be an area for significant stool burden in older adults with stool retention.

Use of X-ray to Assess Fecal Loading in Patients with Gastrointestinal Symptoms

BACKGROUND/AIMS

There is currently no gold standard for evaluating stool burden in the colon for patients with gastrointestinal symptoms. We aim to examine the relationship between fecal loading on single view abdominal X-ray imaging and gastrointestinal symptoms such as constipation, diarrhea, bloating, and accidental bowel leakage in adult outpatients.

METHODS

This retrospective, cross-sectional study examined patients seen at University of Michigan from 2005 to 2017. Chart review of demographic information, reported gastrointestinal symptoms, past medical history, and abdominal radiographic imaging was performed. Bivariate analysis was performed to assess associations between these characteristics and fecal loading. Factors independently associated with fecal loading were identified using logistic regression. Significance was established at p < 0.05.

RESULTS

In total, 319 patients who had an X-ray were included in the final analysis, with 84.0% demonstrating fecal loading on the initial X-ray and most reporting constipation as a symptom (n = 214, 84.3%, p = 0.0334). In logistic regression, a chief complaint of constipation had higher odds of being associated with fecal loading on X-ray compared to diarrhea (adjusted OR 6.41; CI 1.51-27.24, p = 0.0118). Bloating as a reported symptom was statistically significant with an adjusted OR of 2.56 (CI 1.10-5.96, p = 0.0286).

CONCLUSIONS

Constipation (as a chief complaint) and bloating (as a symptom) were associated with fecal loading on X-ray imaging, while accidental bowel leakage and diarrhea were not.