Transient loss of Polycomb components induces an epigenetic cancer fate.

Although cancer initiation and progression are generally associated with the accumulation of somatic mutations1,2, substantial epigenomic alterations underlie many aspects of tumorigenesis and cancer susceptibility3-6, suggesting that genetic mechanisms might not be the only drivers of malignant transformation7. However, whether purely non-genetic mechanisms are sufficient to initiate tumorigenesis irrespective of mutations has been unknown. Here, we show that a transient perturbation of transcriptional silencing mediated by Polycomb group proteins is sufficient to induce an irreversible switch to a cancer cell fate in Drosophila. This is linked to the irreversible derepression of genes that can drive tumorigenesis, including members of the JAK-STAT signalling pathway and zfh1, the fly homologue of the ZEB1 oncogene, whose aberrant activation is required for Polycomb perturbation-induced tumorigenesis. These data show that a reversible depletion of Polycomb proteins can induce cancer in the absence of driver mutations, suggesting that tumours can emerge through epigenetic dysregulation leading to inheritance of altered cell fates.

Basal and stimulated calcitonin for the diagnosis of medullary thyroid cancer: updated thresholds and safety assessment.

PURPOSE: Reliable cut-offs for basal (bCT) and calcium stimulated calcitonin (casCT) are needed for an early and accurate diagnosis of medullary thyroid cancer (MTC). PATIENTS AND METHODS: Fifty-four new patients with nodular goiter were enrolled and analysed together with those previously published by our group for a total of 135 cases. bCT and casCT were measured by a highly sensitive method and the results compared with histological findings. In a subgroup of patients, cardiac rhythm was recorded before and during the calcium test. RESULTS: In both females (F) and males (M), there was a significant correlation between tumor size and bCT levels (P < 0.001). The receiver operating characteristic plot analyses showed that, for bCT, the new cut-off points able to separate non-MTC from MTC patients were > 30 (F) and > 34 pg/mL (M), whereas the best casCT thresholds were > 79 (F) and > 466 pg/mL (M). bCT was shown to harbour a high accuracy, though some cases were diagnosed only upon stimulation test. Importantly, combining bCT, below or above the cut-offs, with casCT above the cut-offs, all the MTC cases were correctly identified. A reversible sinus bradycardia was observed in 9% of cases during the test. CONCLUSIONS: Refined cut-offs for bCT and casCT in patients with nodular goiter are reported. Sensitive bCT was shown to have a high accuracy, but the combination with casCT data was needed to identify all MTC cases. The reliability and safety of calcium test strongly favour the routine use of CT determination in nodular thyroid disease.

Two nasal swabs may not be enough to exclude SARS-CoV-2 infection in symptomatic patients.

Abstracts: The spread of COVID-19 (COronaVIrus Disease 2019), due to SARS-CoV-2 (Severe Acute Respiratory Syndrome CoronaVirus 2) has taken on dramatic pandemic proportions, affecting over 100 countries in a matter of weeks. Italy has had 237,828 confirmed cases according to the Istituto Superiore di Sanità as of May 13, and 34,448 deaths (1).

The epidemiology of osteoporosis in Italian postmenopausal women according to the National Bone Health Alliance (NBHA) diagnostic criteria: a multicenter cohort study.

PURPOSE: The study was aimed at evaluating the prevalence of osteoporosis, defined by BMD and the National Bone Health Alliance (NBHA) criteria, and the prevalence of clinical risk factors for fractures in Italian postmenopausal women. METHODS: This is a cross-sectional, multicenter, cohort study evaluating 3247 postmenopausal women aged ≥ 50 and older in different areas of Italy in the period 2012-2014. All the participants were evaluated as far as anthropometrics; questionnaires for FRAX® and DeFRA calculation were administered and bone mineral density was measured at lumbar spine, femoral neck and total hip by DXA. RESULTS: The prevalence of osteoporosis, as assessed by BMD and NBHA criteria was 36.6 and 57%, respectively. Mean ± SD values of FRAX® and DeFRA were: 10.2 ± 7.3 and 11 ± 9.4 for major fractures, and 3.3 ± 4.9 and 3.9 ± 5.9 for hip fractures, respectively. Among clinical risk factors for fracture, the presence of previous fracture, particularly non-spine/non-hip fracture, parental history of hip fracture and current smoking were the most commonly observed. CONCLUSIONS: Our study showed that more that the half of postmenopausal women aged 50 and older in Italy has osteoporosis on the basis of the NBHA criteria. There is a relevant high risk of femur fracture, as assessed by the FRAX® and DeFRA and previous fracture, parental history of hip fracture and current smoking are the most common risk factors. The data should be considered particularly in relation to the need to increase prevention strategies on modifiable risk factors and therapeutic intervention.

Interventions for cancer-related fatigue: a scoping review.

Cancer-related fatigue (CRF) is common and can be distressing for some survivors. There is increasing interest in measuring levels of CRF, highlighting its impact on quality of life. This review describes the nature and scope of evidence relating to interventions for CRF. Scoping review methodology was used to identify studies, extract data, collate and summarise results. Data were collated according to cancer tumour streams, stage of illness and the types of trial interventions. A total of 447 trials and 37 systematic reviews met the inclusion criteria. Nine papers reported longitudinal results. Populations studied were predominantly of mixed cancer diagnoses and breast cancer. The most frequent interventions were exercise, pharmacological, psycho-education and mind-body interventions. Fatigue was identified as a primary outcome measure (OM) in 58% of studies, with 58 different fatigue measures reported. Emerging evidence exists for the effectiveness of fatigue interventions for some cancer types. More research on interventions with participants with the same cancer type and illness phase is needed. Measurement of severity and impact of CRF using fewer, robust OMs will permit comparisons across studies.

Integration of Homeopathy and Complementary Medicine in the Tuscan Public Health System and the Experience of the Homeopathic Clinic of the Lucca Hospital.

INTRODUCTION: The healthcare programs of the Region of Tuscany (Italy) have started the process of integration of some types of complementary medicine (CM), including homeopathy, which began in 1996. The Homeopathic Clinic of Lucca was opened in 1998, followed by the Homeopathic Clinic for Women in 2003, and the Clinic for CM and Diet in Oncology in 2013. METHODS: Observational longitudinal studies conducted on 5,877 patients (3,937 in the general clinic, 1,606 in the women's clinic and 334 in oncology) were consecutively examined from 2003 to 2016. The Outcome in Relation to Impact on Daily Living (ORIDL) was generally used to assess outcomes. RESULTS: Comparing the clinical conditions before and after homeopathic treatment, improvement was observed in 88.8% of general medicine patients with follow-up (45.1%); in particular, 68.1% of the patients had a major improvement in or resolution (ORIDL +2, +3, +4) of their condition. In women, an improvement was obtained in 74.1% cases and a major improvement in 61.2%. In cancer patients with homeopathic and integrative treatment, a significant improvement was observed for all the symptoms during anti-cancer therapy, particularly for hot flashes, nausea, depression, asthenia, and anxiety. CONCLUSIONS: These results suggest that homeopathy can effectively be integrated with allopathic medicine and that the Tuscan experience could provide a useful reference for developing national and European regulations on the use of CM and homeopathy in public healthcare.

Impact of bevacizumab containing first line chemotherapy on recurrent disease in epithelial ovarian cancer: A case-control study.

OBJECTIVE: To evaluate the timing and pattern of relapse, and duration of response to second line chemotherapy in advanced ovarian cancer (AOC) patients treated with first line carboplatin-paclitaxel chemotherapy with or without bevacizumab. PATIENTS AND METHODS: This is a case-control study including 222 AOC patients. Seventy-four women treated with first line carboplatin-paclitaxel-bevacizumab chemotherapy (Cases) were matched based on laparoscopic predictive index value, and residual tumor at first surgery with 148 AOC patients treated with carboplatin-paclitaxel. Distribution of pattern of relapse, and response to second line chemotherapy was compared between the two groups. Time to Progression (TTP) for second line chemotherapy was also analyzed for study purpose. RESULTS: Median platinum-free interval (PFI) was 16months (range 2-65) in Cases, compared with 9months (1-83) in Controls (p-value=0.001). Twenty patients (51.3%) among Cases showed recurrence in multiple anatomic sites, compared with 31 (31.9%) in the Control group (p-value=0.035). Peritoneal recurrence occurred as diffuse in 30 Cases (96.8%), and 60 Controls (82.2%; p-value=0.046). Secondary cytoreductive surgery (SCS) was successfully completed in 53.5% of Controls compared to 10.0% of Cases (p-value=0.016). In women with fully platinum-sensitive relapse, response rate to second line chemotherapy was 85.2% in Controls, compared to 38.4% in Cases (p-value=0.002). Finally, Cases showed a shorter TTP, compared to Controls (5months vs 8months; p-value=0.041). CONCLUSIONS: Incorporation of bevacizumab into upfront regimens prolongs PFI in AOC patients, but is associated with wider presentation of relapse, lower rate of complete SCS, and shorter TTP to second line chemotherapy in women with platinum-sensitive disease.

Phase II study of NGR-hTNF in combination with doxorubicin in relapsed ovarian cancer patients.

BACKGROUND: The NGR-hTNF (asparagine-glycine-arginine-human tumour necrosis factor) is able to promote antitumour immune responses and to improve the intratumoural doxorubicin uptake by selectively damaging tumour blood vessels. METHODS: Patients progressing after ≥ 1 platinum/taxane-based regimen received NGR-hTNF 0.8 µg m(-2) and doxorubicin 60 mg m(-2) every 3 weeks. Primary endpoint was a Response Evaluation Criteria in Solid Tumors-defined response rate with a target of more than 6 out of 37 responding patients. RESULTS: A total of 37 patients with platinum-free interval lower than 6 months (PFI<6; n=25), or between 6 and 12 months (PFI=6-12; n=12) were enrolled. Median baseline peripheral blood lymphocyte count (PBLC) was 1.6 per ml (interquartile range, 1.2-2.1). In all, 18 patients (49%) received more than 6 cycles. Febrile neutropaenia was registered in one patient (3%). Among 35 assessable patients, 8 (23%; 95% CI 12-39%) had partial response (2 with PFI<6; 6 with PFI=6-12) and 15 (43%) had stable disease (10 with PFI<6; 5 with PFI=6-12). Median progression-free survival (PFS) was 5.0 months for all patients, 3.8 months for patients with PFI<6, and 7.8 months for patients with PFI=6-12. Median overall survival (OS) was 17.0 months. Patients with baseline PBLC higher than the first quartile had improved PFS (P=0.01) and OS (P=0.001). CONCLUSION: Tolerability and activity of this combination warrant further randomised testing in patients with PFI<6. The role of PBLC as a blood-based biomarker deserves further investigation.

Cytokine genetic profile in Whipple's disease.

Whipple's disease (WD) is a very rare chronic systemic condition characterised by a Th2/T regulatory (Treg) dysregulated immune response versus Tropheryma whipplei, a bacterium widely diffuse in the environment. To investigate whether this Th2/Treg polarised response has a genetic background, we investigated the Th1, Th2, Th17 and Treg cytokine genetic profile of 133 patients with WD. Thanks to the European Consortium on WD (QLG1-CT-2002-01049), the polymorphism of 13 cytokine genes was analysed in 111 German and 22 Italian patients using the polymerase chain reaction with sequence-specific primers (PCR-SSP) technique. The frequencies of the genotypes, haplotypes and functional phenotypes were compared with those obtained in 201 German and 140 Italian controls. Clinical heterogeneity was also considered. Functionally, WD patients may be considered as low producers of TGF-ß1, having an increased frequency of the genotype TGF-ß1+869C/C,+915C/C [12.3 % vs. 3.81 %, odds ratio (OR) = 4.131, p = 0.0002] and high secretors of IL-4, carrying the genotype IL-4-590T/T (5.34 % vs. 1.17 %, OR = 5.09, p = 0.0096). No significant association was found between cytokine polymorphism and clinical variability. Analogously to the recent cellular findings of a Th2/Treg polarised response, we showed that the cytokine genetic profile of WD patients is skewed toward a Th2 and Treg response. This was similar in both German and Italian populations. However, the significant deviations versus the controls are poorer than that expected on the basis of these recent cellular findings.

Effect of buspirone, a 5-HT1A receptor agonist, on esophageal motility in healthy volunteers.

There are limited data concerning the effects of 5-HT(1A) receptor activation on esophageal motility. Sumatriptan, a 5-HT(1A) receptor agonist, was recently reported to enhance esophageal peristalsis after intravenous administration. Buspirone, an orally available 5-HT(1A) receptor agonist, was shown to modulate gastroduodenal motor function. Our aim was to evaluate the effect of buspirone on esophageal motility of healthy volunteers. On two separate visits, 20 healthy volunteers aged 21-29 years (nine women) underwent esophageal manometry before and 10, 30, and 60 minutes after the administration of buspirone 20-mg or placebo capsule, according to a double-blind crossover design. At each time point, we compared buspirone and placebo effects on: resting pressure of the lower esophageal sphincter (LES); residual pressure and duration of LES relaxation; amplitude, duration, and onset velocity of esophageal body contractions, during 10 swallows of 5 mL of water. Significant analysis of variance differences (P < 0.05) are presented as mean ± standard deviation. Buspirone significantly increased mean distal esophageal wave amplitude (151 vs. 87 mmHg, P < 0.05) and duration (6.1 vs. 4.2 seconds, P < 0.05). Similarly, buspirone significantly increased mean LES resting pressure (26 vs. 21 mmHg, P < 0.05) and mean residual LES pressure (7.9 vs. 2 mmHg, P < 0.05), whereas reduced mean LES relaxation duration (7.2 vs. 8.0 seconds, P < 0.05) and mean distal onset velocity (7.6 vs. 14.7 cm/second, P < 0.05). Buspirone enhances esophageal peristalsis and LES function in healthy volunteers. Further study is warranted on the effects of buspirone on esophageal function and symptoms in patients with ineffective esophageal motility.

Healthcare-acquired infections in rehabilitation units of the Lombardy Region, Italy.

BACKGROUND: Little data are available on the frequency and risk factors for infection in patients in rehabilitation units. METHODS: This was a 2-year retrospective cohort study conducted in 131 rehabilitation units (RUs) of the Lombardy Region, including those for patients requiring musculoskeletal, cardiac, respiratory, neurological and general geriatric rehabilitation. RUs were stratified into three groups by infection rate calculated from administrative data, and a random sample of RUs in each group was selected for analysis. Discharges from these RUs were randomly selected for chart review, and healthcare-acquired infection was confirmed using CDC/NHSN definitions. A logistic regression analysis explored the association among demographic variables of age, sex, type of rehabilitation unit, Charlson comorbidity score, and location prior to RU admission for selected infections. RESULTS: For the 3,028 discharges from 28 RUs, hospital administrative data had a sensitivity of 0.45 and a positive predictive value of 0.89 to identify infections in the chart review. At least one infection occurred in 14.9% of patient discharges, with 71% of infections being urinary, 8.0% respiratory, and 5% skin and soft tissue. Urinary infection was associated with female sex [odds ratio (OR) 1.48, 95% confidence interval (CI) 1.13-1.93], age 75-85 years (OR 2.21, 95% CI 1.12-4.34), Charlson comorbidity score of ≥3 (OR 1.54, 95% CI 1.10-2.17), and the transfer from acute care (OR 1.45, 95% CI 1.04-2.02). For respiratory infection, male sex (OR 3.06, 95% CI 1.51-6.18), comorbidity score of 1 or 2 (OR 2.16, 95% CI 1.08-4.36), and transfer from a healthcare setting other than an acute care hospital were independent risks (OR 3.14, 95% CI 1.15-8.53). CONCLUSION: Infections are common in residents of these rehabilitation units, and risk factors may differ with type of infection. The proportion of infections which may be prevented and effective prevention strategies need to be determined.

Improving dairy performance through molecular characterization of SREBP-1 gene in Sarda sheep breed.

This research has two aims: (i) to characterize the coding sequence of the SREBP-1 gene in dairy sheep in order to investigate possible relationships between single nucleotide polymorphisms (SNPs) and milk traits; and (ii) to investigate possible relationship between SREBP-1 gene expression and nucleotide variation. Four hundred adult and multiparous lactating Sarda breed ewes were selected from two farms. Milk samples were collected from Day 30 to Day 150 of lactation to determine the mean yield, somatic cell count, lactose, fat, and protein content of the milk. RNA was extracted from the milk samples, after which the SREBP-1 gene coding regions were amplified and sequenced to scan mutations. Whilst eight SNPs were identified, none had statistically significant association with the analysed milk traits. Moreover, the identified expression patterns were not affected by the SNP or combined genotypes. High SREBP-1 gene expression levels were found to be correlated with high milk fat content (P < 0.01), indicating the crucial role of this gene in the milk fat synthesis. In conclusion, the polymorphisms found within SREBP-1 gene exhibited no significant associations with milk traits or with individual SREBP-1 mRNA expression patterns. The findings thus suggest that this small genetic variability may derive from the selection carried out in Sarda breed to improve milk yield.

Unique expression pattern of human nicotinamide mononucleotide adenylyltransferase isozymes in red blood cells.

Nicotinamide mononucleotide adenylyltransferase (NMNAT) catalyzes the formation of nicotinamide adenine dinucleotide (NAD). In humans, three isozymes have been identified: NMNAT1, which is widely expressed in all tissues, NMNAT2 and NMNAT3, which show a tissue-specific expression and whose mRNA levels are generally lower compared to NMNAT1. In the present study we determined the individual NMNAT isozymes activity in human red blood cells (RBCs) by using a biochemical discrimination assay based on the distinctive catalytic properties of the three proteins. We found that isozyme 3 predominates over isozyme 1, whereas isozyme 2 is absent. This high prevalence of NMNAT3 is cell-aging independent and was also confirmed by analyzing the mRNA and protein levels. RBC represent the first human cell type with a remarkable predominance of NMNAT3, and this unique expression pattern is discussed in light of the catalytic properties of the isozymes and in consideration of the biochemical microenvironment of RBC.

NAD(P) biosynthesis enzymes as potential targets for selective drug design.

NAD(P) biosynthetic pathways can be considered a generous source of enzymatic targets for drug development. Key reactions for NAD(P) biosynthesis in all organisms, common to both de novo and salvage routes, are catalyzed by NMN/NaMN adenylyltransferase (NMNAT), NAD synthetase (NADS), and NAD kinase (NADK). These reactions represent a three-step pathway, present in the vast majority of living organisms, which is responsible for the generation of both NAD and NADP cellular pools. The validation of these enzymes as drug targets is based on their essentiality and conservation among a large variety of pathogenic microorganisms, as well as on their differential structural features or their differential metabolic contribution to NAD(P) homeostasis between microbial and human cell types. This review describes the structural and functional properties of eubacterial and human enzymes endowed with NMNAT, NADS, and NADK activities, as well as with nicotinamide phosphoribosyltransferase (NamPRT) and nicotinamide riboside kinase (NRK) activities, highlighting the species-related differences, with emphasis on their relevance for drug design. In addition, since the overall NMNAT activity in humans is accounted by multiple isozymes differentially involved in the metabolic activation of antineoplastic compounds, their individual diagnostic value for early therapy optimization is outlined. The involvement of human NMNAT in neurodegenerative disorders and its role in neuroprotection is also discussed.

Localized cervical cancer (stage

PURPOSE: This study was undertaken to determine the accuracy of magnetic resonance (MR) imaging in the preoperative staging of patients with clinically localised cervical cancer eligible for less extensive surgery. MATERIALS AND METHODS: Fifty-three patients with biopsy-proven carcinoma of the uterine cervix and eligible for conservative surgery prospectively underwent MR imaging. Images were assessed for tumour site and size, infiltration of the cervical stroma, infiltration of vaginal fornices and relationship between the tumour and the internal os of the endocervical canal and the presence and dimensions of pelvic and lumboaortic lymph nodes (cutoff values 1 cm and 0.5 cm minimum axial diameter). MR imaging data were compared with the histopathological findings. RESULTS: The endocervix was the site of origin of 25% (13/53) of the cervical tumours and the exocervix the site of origin of 75% (40/53). In the assessment of cervical stroma infiltration, there was agreement between MR imaging and histopathology in 75% of cases. MR imaging had 67% sensitivity, 92% specificity and 91% diagnostic accuracy in assessing infiltration of the vaginal fornices. In the evaluation of the infiltration of the internal os, MR imaging had 86% sensitivity, 93% specificity and 92% accuracy. In the assessment of the lymph nodes, when using a cutoff value of 1 cm, MR imaging had a sensitivity, specificity and diagnostic accuracy of 28%, 100% and 89%, respectively. With a cutoff value of 0.5 cm, MR imaging had a sensitivity, specificity and diagnostic accuracy of 33%, 92% and 83%, respectively. CONCLUSIONS: MR imaging had a high level of accuracy in the preoperative assessment of the extent of cervical tumour in patients eligible for conservative surgery. Accuracy is lower in the evaluation of the pelvic and lumboaortic lymph nodes.

HDL cholesterol and bone mineral density in normal-weight postmenopausal women: is there any possible association?

AIM: Epidemiological investigation of the association between lipid profile, atherosclerosis and bone mass has produced conflicting RESULTS: The present paper reports the assessment of the lipid profile, bone mineral density (BMD) and turnover in a cohort of Italian women. METHODS: In this cross sectional study we enrolled 173 women in menopause (101 osteoporotic and 72 normal). In each subject the authors evaluated BMD, bone turnover, lipid profile (total cholesterol, high density lipoprotein [HDL], low density lipoprotein [LDL] and triglycerides), and risk factors for osteoporosis, cardiovascular diseases and eating habits using a questionnaire. RESULTS: HDL was significantly higher in osteoporotic patients than in controls and the risk of osteoporosis was significantly higher in women with higher level of HDL. The authors suggest that the level of HDL could be used as screening for postmenopausal osteoporosis: the cut-off points recommended are HDL >61 mg/dL to detect women with a high risk (sensitivity 74%) and <45 mg/dL to detect those with a low risk (specificity 83%). CONCLUSION: This study provides evidences of the relation between HDL, but not total cholesterol or LDL levels with BMD in a cohort of normal-weight women and equally distributed cardiovascular risks. It also suggests that a proatherogenic lipid profile is associated with higher bone mineral density, and that HDL can be used in deciding whether a patient's BMD should be measured.

The Driver Behaviour Questionnaire for older drivers: Do errors, violations and lapses change over time?

The aim of the current study was to examine how self-reported aberrant driving behaviours change across a three time-points in a group of older drivers. Two hundred and twenty-seven older drivers (males = 69.6%) from the Candrive/Ozcandrive longitudinal study completed the Driving Behaviour Questionnaire (DBQ) each yearacross three time-points (i.e., Year 1, Year 2, Year 3). At the third time-point, older drivers ranged in age from 77 to 96 years (M = 81.74 years; SD = 3.44 years). A longitudinal confirmatory factor analysis showed that a modified 21-item, 3-factor (errors, lapses and violations) DBQ was invariant across the time period, suggesting that the structure of the questionnaire was stable across each time-point. Further, multiple domain latent growth analysis on the resultant factors for errors, lapses and violations showed that the frequency of errors remained similar across the three-year period, while violations and lapses showed very marginal decreases in frequency. These changes were independent of the absolute number of these behaviours; Drivers with higher violations or lapses in Year one, showed similar decreases in frequency as those who self-reported lower frequencies of the behaviours. These results suggest that the DBQ is a reliable tool to measure older drivers' self-reported aberrant driving behaviours, and that these behaviours do not show much change across time. Future research should validate the self-reported responses from the DBQ with more objective measures such as those collected through naturalistic driving study (NDS) methodology or on-road driving tasks.

Are older drivers' driving patterns during an on-road driving task representative of their real-world driving patterns?

OBJECTIVE: The current study investigated whether older drivers' driving patterns during a customized on-road driving task were representative of their real-world driving patterns. METHODS: Two hundred and eight participants (male: 68.80%; mean age = 81.52 years, SD = 3.37 years, range = 76.00-96.00 years) completed a customized on-road driving task that commenced from their home and was conducted in their own vehicle. Participants' real-world driving patterns for the preceding 4-month period were also collected via an in-car recording device (ICRD) that was installed in each participant's vehicle. RESULTS: During the 4-month period prior to completing the on-road driving task, participants' median real-world driving trip distance was 2.66 km (interquartile range [IQR] = 1.14-5.79 km) and their median on-road driving task trip distance was 4.41 km (IQR = 2.83-6.35 km). Most participants' on-road driving task trip distances were classified as representative of their real-world driving trip distances (95.2%, n = 198). CONCLUSIONS: These findings suggest that most older drivers were able to devise a driving route that was representative of their real-world driving trip distance. Future research will examine whether additional aspects of the on-road driving task (e.g., average speed, proportion of trips in different speed zones) are representative of participants' real-world driving patterns.

Visceral hypersensitivity and intolerance symptoms in lactose malabsorption.

Lactose malabsorption is not always associated with intolerance symptoms. The factors responsible for symptom onset are not yet completely known. As differences in visceral sensitivity may play a role in the pathogenesis of functional symptoms, we evaluated whether an alteration of visceral sensitivity is present in subjects with lactose intolerance. Thirty subjects, recruited regardless of whether they were aware of their capacity to absorb lactose, underwent an evaluation of intestinal hydrogen production capacity by lactulose breath test, followed by an evaluation of lactose absorption by hydrogen breath test after lactose administration and subsequently an evaluation of recto-sigmoid sensitivity threshold during fasting and after lactulose administration, to ascertain whether fermentation modifies intestinal sensitivity. The role of differences in gastrointestinal transit was excluded by gastric emptying and mouth-to-caecum transit time by (13)C-octanoic and lactulose breath tests. Lactulose administration induced a significant reduction of discomfort threshold in subjects with lactose intolerance but not in malabsorbers without intolerance symptoms or in subjects with normal lactose absorption. Perception threshold showed no changes after lactulose administration. Severity of symptoms in intolerant subjects was significantly correlated with the reduction of discomfort thresholds. Visceral hypersensitivity should be considered in the induction of intolerance symptoms in subjects with lactose malabsorption.