Probiotics: which and when?

There is a natural feeling between our intestinal flora and the gut. These microorganisms, living in the various tracts of human intestine, may affect the host homeostasis. Some of these bacteria can perhaps be a source of infection and sepsis when the bowel barrier is physically or functionally breached. The term 'probiotic' dates from the beginning of the last century and in the last years a market for probiotics worldwide, estimated to be worth billions of pounds, has developed. Although there is persuasive advertising for probiotics and there have been methodological advances in the study of the intestinal microbiota, much remains unproven, e.g. how probiotics work, which strains are effective, what can be expected to be achieved, and what dosage is required for effectiveness. This review of the literature is an evidence-based guide through the developing microbial universe affecting our life.

Hydrogen peroxide-related colitis (previously known as "pseudolipomatosis"): a series of cases occurring in an epidemic pattern.

We report several cases of hydrogen peroxide-related colitis that occurred in an epidemic pattern in our gastrointestinal endoscopy center during a 2-month period in early 2007. During colonoscopy using sterilized endoscopes that had been flushed with hydrogen peroxide after the peracetic acid cycle, instantaneous effervescence and blanching (the "snow white sign") were observed on the intestinal mucosa when the water button was depressed. Biopsy specimens revealed features resembling a clinical condition which used to be known as "pseudolipomatosis." At follow-up, no patient was found to have suffered morbidity associated with this peroxide colitis. Endoscopists should consider hydrogen peroxide colitis when they see a snow white sign during colonoscopy which cannot be attributed to active inflammation or organic disease of the digestive tract.

A highly accurate method for monitoring histological recovery in patients with celiac disease on a gluten-free diet using an endoscopic approach that avoids the need for biopsy: a double-center study.

BACKGROUND AND STUDY AIM: Endoscopy with duodenal biopsy is often performed in order to assess histological recovery in patients with celiac disease who are on a gluten-free diet. Use of the "immersion" technique during upper endoscopy allows visualization of duodenal villi or detection of total villous atrophy. In this two-center study, we investigated the accuracy of the immersion technique in predicting histological recovery in patients on a gluten-free diet whose initial diagnosis of celiac disease had been made on the basis of total villous atrophy. PATIENTS AND METHODS: The immersion technique was performed in 62 patients with celiac disease who were being treated and who had been referred for follow-up (26 patients at the Rome center and 36 patients at the Vicenza center). All these patients had an initial diagnosis based on positive antibodies and biopsy-proved duodenal total villous atrophy. At the follow-up examination, the duodenal villi were re-evaluated as present or absent by one endoscopist at each center, and the results were compared with the histology. RESULTS: At the follow-up endoscopy, the duodenal villi were found to be present in 51 patients and absent in 11. The sensitivity, specificity, positive predictive value, and negative predictive value of the immersion technique for detecting the presence or absence of villi were all 100 %. CONCLUSIONS: This study demonstrated the feasibility and the high level of accuracy of the immersion technique in predicting the histological recovery of duodenal villi in patients with celiac disease who are following a gluten-free diet. An endoscopy-based approach that avoids the need for biopsy could be useful for monitoring the dietary adherence and/or response of patients with an initial diagnosis of celiac disease based on total villous atrophy.

Helicobacter pylori infection and ischaemic heart disease: an overview of the general literature.

In the last years, a considerable number of studies have been performed on the correlation between Helicobacter pylori infection and ischaemic heart disease. The reason is the supposed role of some chronic infections in the genesis and development of vessel wall injury and atheromatous plaque, as already reported for Chlamydia pneumoniae and herpes viruses. While this association may be theoretically conceivable, it still remains debated from a practical point of view. Epidemiological and animal studies as well as some eradicating trials gave conflicting results, while studies investigating the specific molecular mimicry mechanisms induced by H. pylori strongly support the association. Moreover, none of the studies performed so far did take into account the effect of the genetic susceptibility to develop ischaemic heart disease or to respond to H. pylori infection. In particular, while the exposure to some known risk factor for atherosclerosis should lead to develop ischaemic heart disease, no condition or exposure, either individual or in combination, completely explains the occurrence and the progression of the disease, as many patients develop ischaemic heart disease in the absence of any risk factor. Based on these concepts, can we state that H. pylori infection may cause the same effect in patients with ischaemic heart disease as in healthy subjects? Further studies are needed in order to clarify this issue.

High efficacy of 1-week doxycycline- and amoxicillin-based quadruple regimen in a culture-guided, third-line treatment approach for Helicobacter pylori infection.

BACKGROUND: Helicobacter pylori infection may persist after both first- and second-line current treatments. AIM: To assess the efficacy of a third-line, culture-guided treatment approach for the eradication of H. pylori. METHODS: Patterns of resistance were analysed in H. pylori isolates from 94 consecutive patients in whom H. pylori infection had persisted after two eradication attempts. Using the epsilometer test, susceptibility analysis was performed for amoxicillin, clarithromycin, metronidazole, tetracycline and levofloxacin. Patients were then treated with a culture-guided, third-line regimen: 89 patients with a 1-week quadruple regimen including omeprazole, bismuth, doxycycline and amoxicillin, and five patients with a 1-week triple regimen containing omeprazole, amoxicillin and levofloxacin or clarithromycin. RESULTS: Ninety-four subjects (100%) were resistant to metronidazole, 89 (95%) to clarithromycin, 29 (31%) to levofloxacin and five (5%) to tetracycline. No resistance to amoxicillin was found in any patient. Overall, H. pylori eradication was obtained in 90% of subjects. The quadruple regimen was effective in 81 patients (92% by per protocol and 91% by intention-to-treat analysis). Four patients (80%, both per protocol and intention-to-treat analysis) were H. pylori-negative after the triple regimen. CONCLUSIONS: A culture-guided, third-line therapeutic approach is effective for the eradication of H. pylori. Furthermore, the 1-week doxycycline- and amoxicillin-based quadruple regimen is a good third-line 'rescue' treatment option.

Systemic thrombin generation in cancer patients is correlated with extrinsic pathway activation.

Since the first report by Trousseau in 1865, several experimental and clinical studies have established that activation of coagulation is common in cancer. However, the biochemical basis of the activation of coagulation in cancer patients is still not completely understood. The current most accepted opinion is that initiation of coagulation in malignancy is driven primarily by activation of the extrinsic (tissue factor-dependent) pathway. In order to further prove that such a pathogenetic mechanism is actually involved in cancer patients, we correlated the plasma levels of activated factor VIIa (FVIIa), which represent a very small fraction of plasma FVII, with some well-established markers of systemic thrombin generation. Circulating FVIIa was measured using a prothrombin time-based assay that employs a truncated form of human recombinant tissue factor, while plasma levels of the thrombin-antithrombin complex, the prothrombin fragments 1 + 2 and D-dimer were determined by commercially available ELISA kits. The study was carried out in 37 patients with different types of cancer and 20 healthy controls. Plasma levels of FVIIa were significantly increased while those of FVII antigen (FVIIag) were decreased in cancer patients compared with controls. Furthermore, the FVIIa/ VIIag ratio was more than two-fold higher in cancer patients than in controls. In addition, an excess of thrombin generation was observed in cancer patients. Interestingly, a positive correlation between the FVIIa/VIIag ratio and the plasma levels of either D-dimer (Spearman's r = 0.325; P = 0.027) or prothrombin fragments 1 + 2 (r = 0.309; P = 0.034) was observed in cancer patients. In conclusion, our study further supports the hypothesis that the tissue factor/VIIa complex is the main determinant of coagulation activation in cancer patients. Large clinical studies will be necessary to determine whether FVIIa and the FVIIa/VIIag ratio are useful prognostic factors of thromboembolic events in cancer patients.

[A case of chondromatous hamartoma of the lung in 2 places]. / Su un caso di amartoma condromatoso del polmone a duplice localizzazione.

A case of chondromatous hamartoma of the lung, with a double localization (right upper and middle lobes observed in a 62-year old man and treated by bilobectomy is presented. A short review of the pertinent literature is also reported.