Does training and experience influence the accuracy of computed tomography colonography interpretation?

AIM: To evaluate the effect of experience on the accuracy rate of computed tomography colonography (CTC) interpretation and patient preferences/satisfaction for CTC and colonoscopy. METHODS: A prospective, non-randomized, observational study performed in a single, tertiary care center involving 90 adults who underwent CTC followed by colonoscopy on the same day. CTC was interpreted by an abdominal imaging radiologist and then a colonoscopy was performed utilizing segmental un-blinding and re-examination as required. A radiology resident and two gastroenterology (GI) fellows blinded to the results also interpreted the CTC datasets independently. Accuracy rates and trend changes were determined for each reader to assess for a learning curve. RESULTS: Among 90 patients (57% male) aged 55 ± 8.9 years, 39 polyps ≥ 6 mm were detected in 20 patients and 13 polyps > 9 mm in 10 patients. Accuracy rates were 88.9% (≥ 6 mm) and 93.3% (> 9 mm) for the GI Radiologist, 89.8% (≥ 6 mm) and 98.9% (> 9 mm) for the Radiology Resident and 86.7% and 95.6% (≥ 6 mm) and 87.8% and 94.4% (> 9 mm) for each of the GI fellows respectively. The reader's accuracy rate did not change significantly with the percentage change rate ranging between -1.7 to 0.9 (P = 0.12 to 0.56). Patients considered colonoscopy more satisfactory than CTC (30% vs 4%, P < 0.0001), they felt less anxiety during colonoscopy (36% vs 7%, P < 0.0001), they experienced less pain or discomfort during colonoscopy compared to CTC (69% vs 4%, P < 0.0001) and colonoscopy was preferred by 77% of the participants as a repeat screening test for the future. CONCLUSION: No statistically significant learning curve was identified in CTC interpretation suggesting that further study is required to identify the necessary training to adequately interpret CTC scans.

Hypovitaminosis D in adults with inflammatory bowel disease: potential role of ethnicity.

BACKGROUND: Although vitamin D deficiency occurs in inflammatory bowel disease (IBD), it is currently unclear to what extent ethnicity affects vitamin D levels. Our aim was therefore to determine the ethnic variation in serum 25-hydroxyvitamin D status and its association with disease severity in adults with IBD. METHODS: We conducted a prospective cohort study in ambulatory care IBD patients. Clinical disease severity was assessed through validated questionnaires. Serum 25-hydroxyvitamin D levels were used for vitamin D status. C-reactive protein (CRP), ferritin and hemoglobin (Hgb) levels were correlated with serum 25-hydroxyvitamin D levels. RESULTS: Sixty ulcerative colitis (UC) and forty Crohn's disease (CD) patients were enrolled comprising 65 % Caucasians and 29 % South Asians. However, South Asians had consistently lower average serum 25-hydroxyvitamin D levels (All 44.8 ± 18.1 nmol/L, UC 48.2 ± 18.3 nmol/L, CD 24.3 ± 13.3 nmol/L). Hypovitaminosis D was found in 39 % of All, 36.7 % of UC and 42.5 % of CD patients. A significantly higher proportion of South Asians were vitamin D deficient when compared to Caucasians in All and CD groups (58.6 % vs. 30.8 %, p = 0.01 and 85.7 % vs. 32.3 %, p < 0.01, respectively). CONCLUSIONS: A significantly higher percentage of South Asians had hypovitaminosis D when compared to Caucasians. Disease severity trended towards an inverse relationship with vitamin D status in all South Asian and Caucasian CD patients, although most patients in this study had only mild to moderate disease. We suggest that vitamin D supplementation should be considered in all adult IBD patients.

Performance of interferon-gamma release assays in patients with inflammatory bowel disease: a systematic review and meta-analysis.

BACKGROUND: Guidelines mandate screening for latent tuberculosis infection (LTBI) prior to anti-tumor necrosis factor (anti-TNF) therapy in patients with inflammatory bowel disease (IBD). However, many are already on immunosuppressive therapy (IST) that may affect the precision of the Tuberculin skin test (TST). Our aim was to assess the performance of the new interferon-gamma release assays (IGRAs) to detect LTBI in patients with IBD. METHODS: MEDLINE and EMBASE were searched (up to June 2011) to identify studies evaluating the performance of IGRAs (QuantiFERON-TB Gold [QFT-2G], QuantiFERON-TB Gold In-Tube [QFT-3G] and T-SPOT.TB) in individuals with IBD. Forest plots and pooled estimates using random effects models were created where applicable. RESULTS: Nine unique studies encompassing 1309 patients with IBD were included for analysis. The pooled concordance between the TST and QFT-2G/QFT-3G was 85% (95% confidence interval [CI] 77%-90%). The concordance of the TST and TSPOT.TB was 72% (95% CI 64%-78%). Studies assessing agreement reported more IGRA-/TST+ results versus IGRA+/TST- results. The pooled percentage of indeterminate results was 5% (95% CI 2%-9%) for QFT-2G/QFT-3G. TSPOT.TB showed similar results. Both positive QFT-2G/QFT-3G results (pooled odds ratio [OR] 0.37, 95% CI 0.16-0.87) and positive TST results (pooled OR 0.28, 95% CI 0.10-0.80) were significantly influenced by IST (both P = 0.02). CONCLUSIONS: While it remains difficult to determine superiority between the IGRAs and the TST, both are negatively affected by IST. Therefore, screening prior to initiation of IST should be considered. Nevertheless, it is imperative that all patients receive screening prior to anti-TNF therapy.