A comparison between lactose breath test and quick test on duodenal biopsies for diagnosing lactase deficiency in patients with self-reported lactose intolerance.

BACKGROUND: A lactose breath test (LBT) is usually used to diagnose lactase deficiency, and a lactose quick test (LQT) has been proposed as a new test on duodenal biopsies to detect this disorder. GOALS: We aimed to assess the diagnostic accuracy of LBT and LQT and their ability to predict the clinical response to a lactose-free diet in patients with self-reported lactose intolerance. STUDY: Fifty-five patients (age 47 ± 14 y; M/F 15/36) underwent upper gastrointestinal endoscopy and 25g-LBT. Two duodenal biopsies were taken to determine lactase deficiency (normal, mild, or severe) by LQT and to rule out other causes of secondary lactose malabsorption. Patients with a positive LBT and normal LQT also underwent a glucose breath test to exclude small intestinal bacterial overgrowth as a cause of the former result. The severity of gastrointestinal symptoms was measured with a GSS questionnaire, under basal condition and 1 month after a lactose-free diet. RESULTS: Lactose malabsorption was detected in 31/51 patients with LBT and in 37/51 patients with LQT (P = NS). Celiac disease was found in 2 patients. Two LBT+ patients showed a positive glucose breath test for small intestinal bacterial overgrowth. Eight patients had a mild hypolactasia by LQT and a negative LBT, but they had a significant improvement of symptoms after diet. LQT and LBT were concordant in 83% of cases and predicted the response to a lactose-free diet in 98% and 81% of the cases, respectively (P = 0.03). CONCLUSIONS: LQT is as sensitive as LBT in detecting lactase deficiency; however, it seems to be more accurate than LBT in predicting the clinical response to a lactose-free diet.

Risk of microangiopathy in type 2 diabetes mellitus patients with or without chronic hepatitis C: Results of a retrospective long-term controlled cohort study.

BACKGROUND: Patients with chronic hepatitis C have an increased risk of diabetes mellitus but the type and risk of developing diabetes-related complications have not yet been evaluated. METHODS: In order to compare the incidence of diabetic microangiopathy in patients with new onset diabetes without microangiopathy we recruited 54 hepatitis C virus (HCV)-positive and 119 HCV-negative patients from January 2005 to December 2006. All patients were followed-up every 6 months for liver and diabetic complications and incidence of cardiovascular diseases up to December 2012 when data were retrospectively analyzed. RESULTS: The two cohorts were comparable at enrolment except for mean body mass index, obesity rate and family history of diabetes (p=0.007). After 7.2 years of follow-up, 13 HCV-positive (24.1%) and 37 HCV-negative patients (31%) showed at least one microangiopathic complication (p=0.34); 5 HCV-positive (9.3%) and 13 HCV-negative patients (10.8%) reported cardiovascular diseases (p=0.2); 14 HCV-positive (24.5%) compared to 0 HCV-negative patients developed liver-related complications (p=0.0003). One HCV-positive patient died due to liver cancer, 1 HCV-negative patient died from myocardial infarction (p=0.3). Increasing age (HR=1.04, 95% CI: 1.00-1.07, p=0.04) and smoking (HR=2.94, 95% CI: 1.06-8.17, p=0.04) were positively associated to diabetic complications. CONCLUSIONS: Incidence of microangiopathy is not significantly different in diabetics with or without chronic hepatitis C.

The added value of impedance-pH monitoring to Rome III criteria in distinguishing functional heartburn from non-erosive reflux disease.

INTRODUCTION: Functional heartburn is defined by Rome III criteria as an endoscopy-negative condition with normal oesophageal acid exposure time, negative symptom association to acid reflux and unsatisfactory response to proton pump inhibitors. These criteria underestimated the role of non-acid reflux. AIM: To assess the contribution of impedance-pH with symptom association probability (SAP) analysis in identifying endoscopy-negative patients with reflux disease and separating them from functional heartburn. METHODS: Consecutive endoscopy-negative patients treated with proton pump inhibitors (n=219) undergoing impedance-pH monitoring off-therapy were analysed. Distal acid exposure time, reflux episodes, SAP and symptomatic response to proton pump inhibitors were measured. RESULTS: Based on impedance-pH/SAP, 67 (31%) patients were pH+/SAP+, 6 (2%) pH+/SAP-, 83 (38%) hypersensitive oesophagus and 63 (29%) functional heartburn. According to pH-metry alone/response to proton pump inhibitors, 62 (28%) were pH+/SAP+, 11 (5%) pH+/SAP-, 61 (28%) hypersensitive oesophagus and 85 (39%) functional heartburn. In the normal-acid exposure population the contribution of impedance-pH/SAP compared to pH-metry alone/response to proton pump inhibitors in identifying patients with reflux disease and functional heartburn resulted to be 10%. In patients with abnormal-acid exposure, the contribution of impedance-pH/SAP increased by 3%. CONCLUSION: Comparing impedance-pH testing with pH-metry alone plus the response to proton pump inhibitor therapy demonstrated that the latter ones cause underestimation of reflux disease patients and overestimation of functional heartburn patients.

Overweight is a risk factor for both erosive and non-erosive reflux disease.

INTRODUCTION: Studies have reported that the association between overweight and erosive oesophagitis is very strong, whilst seeming less consistent with non-erosive reflux disease. AIM: We have hypothesized that this difference may be due to the heterogeneity of endoscopy-negative population. METHODS: We studied 81 patients with erosive oesophagitis, 48 controls and 295 endoscopy-negative patients classified by impedance-pH-testing as: (1) pH-POS (abnormal acid exposure); (2) hypersensitive oesophagus (normal acid exposure/SAP+); (3) functional heartburn (normal acid exposure/SAP-). Body mass index was also calculated. RESULTS: Mean body mass index was significantly higher (p<0.05) in erosive oesophagitis than in endoscopy-negative patients as a whole and controls [27 (18-40) vs. 25 (16-48) vs. 23 (16-34)]. However, the separation of endoscopy-negative patients showed that mean body mass index was higher (p<0.05) in those with increased acid exposure time [26 (18-45)] than in hypersensitive oesophagus [24 (16-48)]. The former subgroup was similar to erosive oesophagitis, whilst the latter one to both functional heartburn [23 (16-34)] and controls (p=ns). Increased body mass index represented a risk factor for erosive oesophagitis (odds ratio 1.4; 95% confidence interval, 1.2-1.6) and non-erosive reflux disease pH-POS subgroup (odds ratio 1.35; 95% confidence interval, 1.2-1.5). CONCLUSION: Our study shows that overweight represents an important risk factor for erosive oesophagitis and pH-POS non-erosive reflux disease and not for hypersensitive oesophagus and functional heartburn. This provides an explanation for the previously reported lesser role of this variable in non-erosive reflux disease population.