Small intestine bacterial overgrowth and metabolic bone disease.

Small intestine bacterial overgrowth is a malabsorption syndrome and, therefore, it may contribute to the occurrence of metabolic bone disease. However, studies that evaluate the magnitude of this problem and the potential underlying mechanisms are still needed. Fourteen patients with bacterial overgrowth and 22 comparable healthy volunteers took part in this study. All patients were affected by conditions known to predispose to bacterial overgrowth. Diagnosis was based on the following criteria: increased breath hydrogen levels in the fasting state and/or increased breath hydrogen excretion after the ingestion of 50 g of glucose solution, improvement after a 10-day course of antibiotic therapy of severity of symptoms and of H2 excretion parameters. Measurement of bone mineral density by dual-energy x-ray absorptiometry at lumbar spine and femoral level and evaluation of nutritional status were performed. Physical activity, sunlight exposure, and cigarette smoking were also evaluated. Patients showed lumbar and femoral bone mineral density values significantly lower than control group; also the prevalence of bone loss at both lumbar and femoral levels was higher in patient group than in healthy volunteers. Body mass index was significantly lower in patients than in healthy volunteers. Lumbar and femoral bone mineral density were significantly correlated and both correlated with body mass index and with duration of symptoms. No correlation between BMD values and physical activity, sunlight exposure, and cigarette smoking was evident. Our results show that small intestine bacterial overgrowth is an important cofactor in the development of metabolic bone disease. The severity of bone loss is related to poor nutritional status and duration of malabsorption symptoms.

Lactose malabsorption and intolerance in the elderly.

BACKGROUND: Lactase activity declines with age in rats, but it is not clear whether this model is also shared by humans. Few studies have evaluated lactose intolerance and malabsorption in the elderly and no definite conclusions can be drawn. The aim of our study was therefore to verify the impact of age on lactose intolerance and malabsorption. METHODS: Eighty-four healthy subjects took part in the study. Thirty-three were <65 years, 17 were between 65 and 74 years and 34 were >74 years. All the subjects underwent a preliminary evaluation of intestinal gas production capacity and oro-cecal transit time by H2/CH4 breath test after lactulose. After a 3-day period, an H2/CH4 breath test after lactose was performed. The occurrence of intolerance symptoms during the test and in the 24 h after the test was recorded. RESULTS: Breath H2 and CH4 excretion parameters at fasting and after lactulose did not differ between the three groups. Cumulative breath H2 excretion after lactose was higher in subjects >74 years than in subjects <65 years and in subjects aged 65-74 years, while no difference was found between the latter two groups. In subjects >74 years, the prevalence of lactose malabsorption was higher than in the other two groups, while no significant difference was observed between subjects <65 years and subjects aged 65-74 years. Within the malabsorber subjects, the prevalence of lactose intolerance was higher in subjects <65 years than in those aged 65-74 years and in those aged >74 years. No significant difference was found between the latter two groups. No difference was found between the three groups in terms of daily calcium intake and a significant negative correlation between symptom score and daily calcium intake was only found in the group of subjects aged <65 years. CONCLUSIONS: As age increases, the prevalence of lactose malabsorption shows an increase while the prevalence of intolerance symptoms among malabsorbers shows a decrease. Accordingly, daily calcium intake was similar among the adults and elderly studied.

Role of lifestyle factors in the pathogenesis of osteopenia in adult coeliac disease: a multivariate analysis.

OBJECTIVES: Coeliac disease is frequently complicated by alterations of bone mass and mineral metabolism. In this condition the degree of malabsorption is a major determinant of bone loss. However, the role of lifestyle factors such as exposure to sunlight, physical activity and cigarette smoking, which have been demonstrated to influence bone mass and mineral metabolism in other conditions, has never been investigated in coeliac disease. DESIGN: We evaluated the impact of potential co-factors on bone homeostasis in coeliac disease by means of a multivariate analysis model. METHODS: Thirty-nine adult patients with untreated coeliac disease (18 symptomatic, 21 subclinical/silent) were studied. Bone mineral density was measured by dual-energy X-ray absorptiometry at lumbar spine and femoral neck levels. Age at diagnosis, gender, duration of symptoms and severity of symptoms were recorded. Nutritional status, cigarette smoking habit, exposure to sunlight, and physical activity were evaluated. The impact of each independent variable on lumbar and femoral bone mineral density was evaluated by means of a multivariate analysis model. RESULTS: The severity of symptoms and nutritional status were significant sources of variability of both lumbar and femoral bone mineral density. Physical activity was a significant source of variability at femoral level, while gender was at lumbar level. Cigarette smoking habit and exposure to sunlight showed no significant effect on bone mineral density. CONCLUSIONS: Gender, malnutrition, global severity of the disease and physical activity are important co-factors in the pathogenesis of bone loss in coeliac disease.

Early increase of bone resorption in patients with liver cirrhosis secondary to viral hepatitis.

Bone loss is an established complication of cholestatic liver cirrhosis, while little is known about bone mass and metabolism in noncholestatic liver cirrhosis. The aim of the present study is, therefore, to evaluate bone mass and mineral metabolism in patients with liver cirrhosis secondary to viral hepatitis. Bone mineral density measurement at lumbar and femoral levels and the evaluation of bone and mineral metabolism and gonadal function were performed in 31 patients with liver cirrhosis and 37 healthy volunteers. Lumbar and femoral bone mineral density values were significantly lower in patients than in healthy volunteers. Prevalence and severity of bone loss increased according to the severity of liver disease. All serum indices of bone and mineral metabolism and of gonadal function showed a similar behavior, but a significant increase of bone resorption was present in all Child-Pugh classes. In particular, class A patients showed normal mean bone mineral density values but increased serum levels of the telopeptide of type I collagen. Liver cirrhosis predisposes to bone loss regardless of the presence of cholestasis. The severity of metabolic osteopathy worsens as liver function does. The underlying mechanism is represented by an increased bone resorption.

Non-absorbable antibiotics for managing intestinal gas production and gas-related symptoms.

BACKGROUND: Simethicone, activated charcoal and antimicrobial drugs have been used to treat gas-related symptoms with conflicting results. AIM: To study the relationship between gaseous symptoms and colonic gas production and to test the efficacy of rifaximin, a new non-absorbable antimicrobial agent, on these symptoms. METHODS: Intestinal gas production was measured by hydrogen (H2) and methane (CH4) breath testing after lactulose in 21 healthy volunteers and 34 functional patients. Only the 34 functional patients took part in a double-blind, double-dummy controlled trial, receiving, at random, rifaximin (400 mg b.d per 7 days), or activated charcoal (400 mg b.d per 7 days). The following parameters were evaluated at the start of the study and 1 and 10 days after therapy: bloating, abdominal pain, number of flatus episodes, abdominal girth, and cumulative breath H2 excretion. RESULTS: Hydrogen excretion was greater in functional patients than in healthy volunteers. Rifaximin, but not activated charcoal, led to a significant reduction in H2 excretion and overall severity of symptoms. In particular, in patients treated with rifaximin, a significant reduction in the mean number of flatus episodes and of mean abdominal girth was evident. CONCLUSIONS: In patients with gas-related symptoms the colonic production of H2 is increased. Rifaximin significantly reduces this production and the excessive number of flatus episodes.

Rifaximin versus chlortetracycline in the short-term treatment of small intestinal bacterial overgrowth.

BACKGROUND: Bacterial overgrowth of the small intestine is a condition characterized by nutrient malabsorption due to an excessive number of bacteria in the lumen of the small intestine. Current treatment is based on empirical courses of broad spectrum antibiotics; few controlled data, with respect to the duration and choice of antibiotic drug, exist at present. The recent availability of rifaximin, a non-absorbable rifamycin derivative, highly effective against anaerobic bacteria, prompted us to carry out a randomized, double-blind controlled trial in order to compare its efficacy and tolerability to those of tetracycline, currently considered the first-choice drug. METHODS: In 21 patients affected by small intestinal bacterial overgrowth, fasting, peak and total H2 excretion after ingestion of 50 g glucose and severity of symptoms were evaluated before and after a 7-day course of rifaximin, 1200 mg/day (400 mg t.d.s.), or chlortetracycline, 1 g/day (333 mg t.d.s. ). RESULTS: Fasting, peak and total H2 excretion decreased significantly in the group of patients treated with rifaximin whereas chlortetracycline did not modify these parameters. The H2 breath test normalized in 70% of patients after rifaximin and in 27% of patients after chlortetracycline. The improvement in symptoms was significantly higher in patients treated with rifaximin. CONCLUSIONS: Rifaximin is a promising, easily-handled and safe drug for the short-term treatment of small intestinal bacterial overgrowth.

Bone mass and metabolism in dermatitis herpetiformis.

Dermatitis herpetiformis is a gluten-sensitive skin disease with intestinal lesions and malabsorption symptoms less severe than those found in celiac disease. While several studies have shown the occurrence of osteopenia in celiac disease, bone mass and metabolism have never before been evaluated in dermatitis herpetiformis. Therefore, in 16 untreated patients, 16 sex- and age-matched untreated celiac patients, and 16 sex- and age-matched healthy volunteers, lumbar and femoral bone mineral density were measured and bone and mineral metabolism and nutritional status were evaluated. All these parameters were significantly altered in the two groups of patients and although the degree of these alterations was milder in patients with dermatitis herpetiformis than in celiac patients, the presence of subtotal villous atrophy in patients with dermatitis herpetiformis was associated with the presence of more severe alterations. Bone mineral density was significantly correlated with nutritional status, and patients showing bone loss were characterized by a body mass index lower than 20. Alterations of bone mass and mineral metabolism complicate dermatitis herpetiformis when severe intestinal lesions coexist. A low nutritional status may be predictive of the presence of bone loss.

[Intestinal permeability]. / La permeabilità intestinale.

Intestinal mucosa has an absorptive function and acts also as a selective barrier against potential antigenic, toxic and carcinogenic substances. Intestinal permeability can be defined as the capacity of mucosal surface to be penetrate by specific substances through unmediated diffusion. There are two theories about molecular permeation routes: the first one hypothesizes a transcellular (through small pores), a paracellular (through big channels) and a lipophilic pathways; the second one gives a key role only to paracellular tight-junctions. In many diseases we can find changes in intestinal permeability evaluable by simple and non invasive tests, administering "per os" probe molecules. These substances cross the epithelium in different way and amount according to their physicochemical features and mucosal integrity; then they reach circulation and are eliminated in urines where they can be detected. The most frequently molecules used are mono/disaccharides, 51Cr-labelled ethylenediaminetetraacetate (51Cr-EDTA) and polyethylene glycol (PEG). This simple method has become more and more used for diagnostic and speculative aims. These intestinal permeability tests have a low specificity so they cannot be used for a definitive diagnosis of intestinal disease; nevertheless, the high sensitivity for intestinal mucosal damage could make them a necessary method to evaluate mucosal integrity after therapy, to select patients with a specific symptoms and to support, particularly in pediatric populations, more specific and invasive diagnostic tests.

Helicobacter pylori eradication using one-week low-dose lansoprazole plus amoxycillin and either clarithromycin or azithromycin.

AIM: To evaluate and compare two 1-week low-dose triple therapies based on lansoprazole, amoxycillin and a macrolide in eradicating Helicobacter pylori. METHODS: Seventy consecutive patients, suffering from dyspeptic symptoms with H. pylori infection, were randomly allocated to one of two treatment groups: (A) (LAC; n = 35) lansoprazole 30 mg once daily, amoxycillin 1000 mg b.d., clarithromycin 250 mg b.d., all for 7 days; and (B) (LAA; n = 35) lansoprazole 30 mg once daily and amoxycillin 1000 mg b.d., both for 7 days, plus azithromycin 500 mg once daily for only 3 days. The H. pylori status was evaluated by means of histology and rapid urease test at entry and 8 weeks after treatment. RESULTS: Three patients did not complete the treatment: one in the LAC group was withdrawn owing to severe side-effects; two patients in the LAA group stopped the treatment prematurely. H. pylori eradication was obtained in 28 of 34 (82%; 95% CI = 66-93%) patients in the LAC group and in 20 of 33 (61%; 95% CI = 42-77%) patients in the LAA group. The difference is significant (P < 0.029). On intention-to-treat analysis, the rates of eradication were (28 of 35 patients, 80% in the LAC group and 20 of 35 patients, 57% in the LAA group. Side-effects occurred in nine (26%) and six (18%) patients in the LAC and LAA groups, respectively. CONCLUSIONS: Low-dose lansoprazole plus amoxycillin and clarithromycin is more effective than low-dose lansoprazole plus amoxycillin and azithromycin, but it gave a greater incidence of side-effects.

Use of the ''Polymerase Chain Reaction'' for the diagnosis of Helicobacter pylori infection.

PURPOSE: H. pylori infection can be diagnosed by means of non-invasive tests or invasive techniques using endoscopy. The choice of the test depends on available instruments, type of diseases, aim of diagnostic research (therapeutic or epidemiological) and test features. PCR is able to reveal pathogenic germs in biological material with very high sensitivity and specificity. In vitro DNA amplification method consists of hybriding denaturated DNA by means of two oligonucleotide primers that allow to copy DNA fragment. The aim of our study was to determine, using PER, H. pylori colonization in the gastric mucosa of 18 consecutive patients under-went gastroscopy. MATERIALS AND METHODS: Eighteen patients complaining of dyspeptic symptoms and referred to us for upper GI endoscopy participated in the study. The studied population comprised 9 males and 9 females with mean age of 55.4 yrs (range 26-73 years). All patients underwent gastroscopy during which 4 biopsies from the antrum and 4 from the corpus were obtained for Giemsa stain, PCR analysis and histologic examination. A pair of synthetic oligonucleotides for H. pylori urease A gene, designated as HPU1 and HPU2, were used. Urease A gene fragment amplified by PCR was analyzed by 1.5 agarose gel electrophoresis. Positivity for H. pylory corresponded to PCR DNA products migrating at 411 bp after staining with ethidium bromide. RESULTS: The patients were divided into two groups, according to H. pylori infection, determined by means of Giemsa stain: group A, comprising 11 H. pylori-positive patients; and group B, with 7 H. pylori-negative patients. Our PCR assay of gastric mucosa samples proved positive in 7 cases of group A (63.6%), whereas it always proved negative among group B subjects (100%). CONCLUSIONS: Our findings, apparently in contrast with the high sensitivity of PCR, may be attributed to the lower specificity of histology or, alternatively, the absence of H. pylori in the samples tested by PCR due to the patchy distribution of H. pylori colonization in the gastric mucosa. These observations are in agreement with those from other investigations.

Evaluation of the efficacy and tolerability of four different therapeutic regimens for the Helicobacter pylori eradication.

The aim of our study is to evaluate the efficacy and tolerability of four different therapeutic regimens for Helicobacter pylori eradication. One-hundred and thirty-two consecutive patients suffering from either peptic ulcer or non-ulcer dyspepsia, with Helicobacter pylori infection, were allocated to one of the following 4 groups with different therapeutic regimens: A) omeprazole 20 mg bid for 14 days/amoxycillin 1000 mg bid for 14 days/tinidazole 500 mg bid for 14 days (30 patients, 13 with peptic ulcer); B) omeprazole 20 mg bid for 14 days/amoxycillin 1000 mg bid for 14 days (41 patients, 23 with peptic ulcer); C) omeprazole 20 mg bid for 14 days/azithromycin 500 mg/day for 3 days for 2 consecutive weeks (25 patients, 12 with peptic ulcer); D) omeprazole 20 mg/day for 7 days/clarithromycin 250 mg bid for 7 days/tinidazole 500 mg bid for 7 days/ (36 patients, 14 with peptic ulcer). The Helicobacter pylori status was evaluated by means of histology, culture and urease test, at entry and 8 weeks after treatment. 2 group A, B and D patients, 1 D patient didn't complete the treatment. In evaluable patients, the Helicobacter pylori eradication was obtained in 24 patients of group A (85.71%), in 24 of group B (58.98%), in 11 of group C (45.83%) and in 24 of group D (70.58%). On intention-to-treat analysis, Helicobacter pylori eradication was 80% in group A, 56.09% in group B, 44% in group D and 66.67% in group D. Sideeffects occurred in 6 patients of group A (20.68%), in 5 of group B (12.5%), in 3 group D (8.82%) and none of group C. In conclusion, triple therapy with omeprazole/clarithro-mycin/tinidazole is better for cost/benefit ratio; omeprazole/amoxycillin/tinidazole is more effective than others regimens in the Helicobacter pylori eradication, but causes more side effects; double therapy with omeprazole/azithromycin is the most tolerable and the least efficacy for Helicobacter pylori eradication.

One-week low-dose triple therapy vs. two-week medium-dose double therapy for H.pylori infection.

BACKGROUND/AIMS: Our study is to compare a short-term low-dose triple therapy with a long-term medium-dose double therapy for H.pylori eradication. MATERIALS AND METHODS: One hundred and ten consecutive patients, suffering from dyspeptic symptoms, with H.pylori infection, were randomly allocated to one of the following 2 groups with different therapeutic regimens: A) omeprazole 20 mg/day for 7 days, tinidazole 500 mg bid for 7 days, clarithromycin 250 mg bid for 7 days (55 pts, 20 with peptic ulcer); B) omeprazole 20 mg bid for 14 days, amoxycillin 1000 mg bid for 14 days (55 pts, 28 with peptic ulcer). The "H.pylori status" was evaluated by means of histology, culture and urease test, at entry and 8 weeks after treatment. RESULTS: Two group A and one group B pts didn't complete the treatment. The H.pylori eradication was obtained in 38 pts of group A (71.69%) (C.I.95%: 55.19176-80.86293), in 31 of group B (58.49%) (C.I.95%: 42.32777-69.7017); on Intention-to-Treat analysis, the rate of eradication gave similar results. Side effects occurred in 9 pts of group A (16.98%), in 8 of group B (14.81%). CONCLUSIONS: Short-term low-dose triple therapy with omeprazole/tinidazole/clarithromycin has a better cost/benefit ratio than long-term dual therapy with omeprazole/amoxycillin in the H.pylori eradication, but it causes more side-effects.

Low-dose omeprazole plus clarithromycin and either tinidazole or amoxycillin for Helicobacter pylori infection.

BACKGROUND: The aim of our study was to compare two 1-week, low-dose triple therapies for Helicobacter pylori eradication. METHODS: One hundred consecutive patients, suffering from dyspeptic symptoms with H. pylori infection, were randomly allocated to 7 days of treatment with omeprazole 20 mg o.m. plus clarithromycin 250 mg b.d. and either tinidazole 500 mg b.d. (group A: n = 50, 19 with peptic ulcer) or amoxycillin 1000 mg b.d. (group B: n = 50, 20 with peptic ulcer). H. pylori-status was evaluated by means of histology, culture and urease test, at entry and 8 weeks after treatment. RESULTS: Three patients did not complete the treatment. H. pylori eradication was obtained in 35 patients from group A (73%) (95% CI, 55-82%) and in 40 patients from group B (82%) (95% CI, 66-90%). On intention-to-treat analysis, the rates of eradication were similar. Side-effects occurred in seven patients from group A (14.58%) and in four patients from group B (8.33%), but none discontinued therapy because of side-effects. CONCLUSION: Both triple 1-week, low-dose omeprazole therapies gave good eradication rates with infrequent side-effects.

Role of dental plaque in the transmission of Helicobacter pylori infection.

With regard to the role of dental plaque in the transmission of Helicobacter pylori infection, data from the literature vary greatly, owing to differences in sample collection and H. pylori-detecting techniques. Using the polymerase chain reaction (PCR), we have determined the incidence of H. pylori colonization in the dental plaque of 31 consecutive patients who underwent gastroscopy. The patients were divided into two groups on the basis of H. pylori infection, determined by Giemsa stain and the rapid urease test: group A made up of 21 H. pylori-positive patients and group B with 10 H. pylori-negative patients. Our PCR assay of dental plaque samples proved negative in all group A subjects but was positive in only one patient in group B. In our study, we found that H. pylori had a low prevalence (3.2%) in the oral cavity, with no significant relationship between gastric mucosa and dental plaque colonization. More comprehensive studies are needed to determine whether dental plaque is an important reservoir in the epidemiology of H. pylori-induced gastric disease.

Clinical assessment of the relationship of Helicobacter pylori to gastroduodenal pathologies. A prospective analysis of 253 consecutive patients.

The aim of our study was to evaluate the relationship between Helicobacter pylori infection and various gastroduodenal diseases. We also took into consideration alcohol intake and smoking. Two-hundred and fifty-three consecutive patients with ulcer-like symptoms underwent gastroscopic and histological examinations. H. pylori status was evaluated by means of culture, Giemsa stain and CP-test, upon obtaining bioptic samples of gastric mucosa. Two hundred eighteen patients were affected by gastritis, 171 of which were H. pylori positive (78.4%); of 164 patients with active gastritis, 158 were H. pylori positive (96.3%). In 63 patients with duodenal ulcer, H. pylori was present in 58 cases (92.1%). Of 14 patients with gastric ulcer, 11 were H. pylori positive (78.6%). Out of 133 patients with duodenitis associated with active ulcer or a history of previous ulcer, H. pylori was found in 112 patients (84.2%). Among the 27 patients with "autonomous" duodenitis, 18 were H. pylori positive (66.6%); the comparison between the two groups of patients with duodenitis concerning H. pylori infection was statistically significant (p = 0.033). Of the 119 patients tested for acquired MALT, 39 were found positive (32.7%); among these 34 patients were H. pylori positive (87.1%) and only 5 patients were H. pylori negative (12.9%). Thus our study confirms the importance of H. pylori in gastroduodenal pathology underlining its role in the development of acquired MALT (mucosa associated lymphoid tissue) for its possible evolution in low grade B cell primary gastric lymphoma. Alcohol intake and smoking do not appear to play a role in H. pylori infection.