Ong-Ard Praisontarangkul

The Jaundiced Heart: Evidence of Blunted Response to Positive Inotropic Stimulation

Obstructive jaundice has been known to cause severe hemodynamic disturbance. The present study was therefore designed to assess the cardiac involvement in jaundiced patients. The multiple-gated blood pool cardioscintigraphic studies were done in 9 jaundiced patients who had either cholestatic or obstructive jaundice (mean total bilirubin 29.30 +/- 3.30 mg/dL), and in 8 normal volunteers (total bilirubin less than 1 mg%). None of the patients had evidences of obvious cirrhosis, intrinisic heart disease, or septicemia. Following intravenous dobutamine there was comparable change of blood pressure and heart rate in both groups. However the response of left ventricular ejection fraction (LVEF) to dobutamine (10 micrograms/kg/min x 5 min) was strikingly blunted in the jaundiced patients as compared to that seen in the normal controls (3.56 +/- 0.9 vs. 12.7 +/- 2.2%, p less than 0.005). Our present data thus show that there is blunted myocardial contractile response to the inotropic stimulation in jaundiced patients. Such myocardial refractoriness to beta-1 stimulation may contribute to the susceptibility of jaundiced patients to postoperative shock and acute renal failure.

The Optimal Cut-Off Level of The Fecal Immunochemical Test For Colorectal Cancer Screening in a Country with Limited Colonoscopy Resources: A Multi-Center Study from Thailand

Background: Selecting the cut-off point for the fecal immunochemical test (FIT) for colorectal cancer (CRC) screening programs is of prime importance. The balance between the test performance for detecting advanced neoplasia and the available colonoscopy resources should be considered. We aimed to identify the optimal cut-off of FIT for advanced neoplasia in order to minimize colonoscopy burden. Methods: We conducted a multi-center study in 6 hospitals from diverse regions of Thailand. Asymptomatic participants, aged 50-75 years, were tested with one-time quantitative FIT (OC-SENSOR, Eiken Chemical Co.,Ltd., Tokyo, Japan) and all participants underwent colonoscopy. We assessed test performance in detecting advanced neoplasia (advanced adenoma and CRC) and measured the burden of colonoscopy with different cut-offs [25 (FIT25), 50 (FIT50), 100 (FIT100), 150 (FIT150), and 200 (FIT200)ng/ml]. Results: Among 1,479 participants, advanced neoplasia and CRC were found in 137 (9.3%) and 14 (0.9%), respectively. From FIT25 to FIT200, the positivity rate decreased from 18% to 4.9%. For advanced neoplasia, an increased cut-off decreased sensitivity from 42.3% to 16.8% but increased specificity from 84.2% to 96.3%. The increased cut-off increased the positive predictive value (PPV) from 21.5% to 31.5%. However, all cut-off points provided a high negative predictive value (NPV) (>90%). For CRC, the miss rate for FIT25 to FIT 150 was the same (n=3, 21%), whereas that with FIT200 increased to 35% (n=5). Conclusions: In a country with limited-colonoscopy resources, using FIT150 may be preferred because it offers both high PPV and NPV for advanced neoplasia detection. It could also decrease colonoscopy workload, while maintaining a CRC miss rate similar to those with lower cut-offs.

Impact of Fecal Hb Levels on Advanced Neoplasia Detection and the Diagnostic Miss Rate For Colorectal Cancer Screening in High-Risk vs. Average-Risk Subjects: a Multi-Center Study

OBJECTIVES: The Asia‐Pacific Colorectal Screening (APCS) scoring system was developed to identify high‐risk subjects for advanced neoplasia. However, the appropriate fecal immunochemical test (FIT) cutoff for high‐risk population may be different from that of average‐risk population. We aimed to evaluate the FIT performance at different cutoffs in high‐risk subjects undergoing colorectal cancer (CRC) screening. METHODS: We prospectively enrolled asymptomatic subjects aged 50–75 years. Using the APCS score, subjects were stratified into either the average‐risk or high‐risk groups. All subjects were tested with one‐time quantitative FIT and underwent colonoscopy. We compared the FIT performance for advanced neoplasia between two groups using different cutoffs (5 (FIT5), 10 (FIT10), 20 (FIT20), 30 (FIT30), and 40 (FIT40) μg Hb/g feces). RESULTS: Overall, 1,713 subjects were recruited, and 1,222 (71.3%) and 491 (28.7%) were classified as average‐risk and high‐risk, respectively. Advanced neoplasia was detected in 90 (7.4%) of the average‐risk subjects and 65 (13.2%) of the high‐risk subjects. In the high‐risk group, by decreasing the cutoff from FIT40 to FIT5, the sensitivity increased by 33.8 percentage points with decreased specificity by 11 percentage points. In the average‐risk group, the sensitivity increased by 20 percentage points with decreased specificity by 9.6 percentage points. At the lowest cutoff (FIT5), the number of needed colonoscopies to find one advanced neoplasia was 2.8 and 6.1 for the high‐risk and average‐risk groups, respectively. CONCLUSIONS: Using an appropriate FIT cutoff for CRC screening in high‐risk subjects could improve CRC screening performance and reduce the unnecessary colonoscopies. To maintain high sensitivity and specificity for advanced neoplasia, the optimal cutoff FIT in the high‐risk subjects should be lower than that in the average‐risk subjects.