Allergy in adolescent population (14-18 years) living in Campania region (Southern Italy). A multicenter study.

Summary: Adolescents (Ad) constitute a difficult to manage population among individuals suffering from asthma. The aim of our study was to assess the prevalence, clinical characteristics and age of onset of allergic sensitization and clinical symptoms in a sample of atopic Ad living in the Campania region (Southern Italy). Sixteen Allergy units or Centers belonging to the Italian Association of Hospital and Territorial Allergologists (AAIITO, Campania region) participated in this cross-sectional study. A case report form (CRF) was specifically designed for this study and commercial allergen extracts used for screening SPTs were provided by ALK-Abelló Group (Milan, Italy). A total of 443 patients were examined (females, f 220, 49.6 %; males, m 223, 50.3%). Dust mites represent the most common sensitizing agents in allergic Ad living in Campania region (Dermatoph. pteronyssinus 67.4% and Dermatoph. farinae 66.5%), followed by Parietaria (58.9%), grasses (45.8%), Artemisia vulgaris (16.7%), Olea Europaea (32.2%), dog dander (17.1%), cat dander (20.0%), Alternaria alternata (8.1%), Cupressus sempervirens (4.9%), Betula pendula (4.7%), other allergens (19.4%). An interesting comparison has been made between clinical data of our Ad with data of elderly patients (E). The role of allergic sensitization is significantly higher in Ad compared to E. Dermatophagoides pteronyssinus is the first sensitizing allergen in Ad and the last in E. Parietaria constitutes the first sensitizing pollen both in Ad and E, the percentage of sensitization is higher in Ad. Another important difference is the higher prevalence of As, as only symptom, in E compared to Ad (19.7% versus 7.6%). In conclusion, our findings confirm the high prevalence and clinical significance of airway allergic sensitization in the adolescents living in Campania region.

Allergic sensitization to common pets (cats/dogs) according to different possible modalities of exposure: an Italian Multicenter Study.

BACKGROUND: The query "are there animals at home?" is usually administered for collecting information on anamnesis. This modality to consider exposure to pet allergens constitutes a potential bias in epidemiological studies and in clinical practice. The aim of our study was to evaluate/quantify different modalities of exposure to cat/dog in inducing allergic sensitization. METHODS: Thirty Italian Allergy units participated in this study. Each centre was required to collect the data of at least 20 consecutive outpatients sensitized to cat/dog allergens. A standardized form reported all demographic data and a particular attention was paid in relieving possible modalities of exposure to cat/dog. RESULTS: A total 723 patients sensitized to cat/dog were recorded, 359 (49.65%) reported direct pet contact, 213 patients (29.46%) were pet owners, and 146 subjects (20.19%) were exposed to pets in other settings. Other patients were sensitized by previous pet ownership (150-20.75%) or indirect contact (103-14.25%), in 111 subjects (15.35%) any contact was reported. CONCLUSIONS: Only 213 patients (29.46%) would be classified as "exposed to animals" and 510 (70.54%) as "not exposed" according to usual query. Our classification has shown that many "not-exposed" subjects (399-55.19%) were "really exposed". The magnitude of exposure to pet allergens at home is not related exclusively to pet ownership. These considerations should be taken into account during the planning of epidemiological studies and in clinical practice for the management of pet allergic individuals.

Allergy in urban elderly population living in Campania region (Southern Italy). A multicenter study.

Given the increasing life expectancy observed in Western countries, there is a marked interest to know more about how aging could influence respiratory health. The aim of our study was to assess the prevalence, clinical characteristics and age of onset of allergic sensitization and clinical symptoms in a sample of atopic elders living in Campania region area (Southern Italy). Fourteen Allergy units or Centres examined a total of 462 patients. In this context 215 (46.53%) had positive skin prick tests (SPTs) to at least one allergen and were diagnosed with respiratory allergy. Parietaria represents the most common sensitizing agent in elders living in Campania region, followed by dust mites, grass pollen and Olea europaea. A relatively high percentage of atopic subjects suffered from respiratory symptoms at a fairly advanced age, namely 8.3% at 60-64 years, 10.2% at 65-70 and 5.7% at > 70 years. In conclusion, the prevalence and clinical significance of airway allergic sensitization in the elderly living in Campania region is more significant than expected in latter stages of life. Physicians should not neglect the role of atopy as a risk factor for the onset of allergic respiratory symptoms even in elderly patients.

Sensitization to cockroach allergens in the urban atopic populations living in Campania district (southern Italy). A multicenter study.

BACKGROUND: Although cockroach (CR) is an important cause of allergic sensitization worldwide, only a few data are available in Italy and in a previous study we have observed, in Naples area, a low prevalence of CR sensitization. OBJECTIVES: We sought to perform a prospective study for assessing the prevalence of allergic sensitization to CR in a sample of atopic population living in Campania district area (Southern Italy). METHODS: Ten Allergy Units or Centres of Campania district participated in this cross-sectional study. Each centre was required to collect the results of at least 100 allergy consultations in consecutive outpatients referred for actual or suspected respiratory allergy. We registered demographic data, type and duration of respiratory symptoms, pets ownership, possible exposure to CR allergens, results of the skin prick tests (SPTs). RESULTS: A total of 1477 patients were examined, 985 (66.68%) had a SPTs positivity to at least one allergen. In this context, ninety were sensitized to CR, thus the overall sensitization prevalence in subjects with respiratory allergy was 6.09% ranging between 0-11% and only five patients were mono-sensitized. Thirteen patients reported rhinitis (R) + bronchial asthma (A), twenty-one R + A + conjunctivitis (C), thirty-seven R + C, five only A and eleven individuals only R. Sixty-seven patients exhibited persistent and twenty-three intermittent symptoms. Dust mite constituted the first cause of associated sensitization to CR. CONCLUSIONS: The prevalence of allergic sensitization to CR is not negligible in population living in Campania district and shows a higher trend in comparison to that found recently and some years ago in Naples area. Finally, we suggest atopic individuals and especially those highly sensitized to mite allergens or those living in low-income areas to be tested by SPTs / evaluation of serum specific IgE to CR allergens to exclude the occurrence of CR allergic sensitization.

The importance of AIF ROI selection in DCE-MRI renography: reproducibility and variability of renal perfusion and filtration.

PURPOSE: The aim of this study was to investigate (a) the effect the choice of the region of interest (ROI) defining the aortic input function (AIF) has on the estimation of renal perfusion and filtration in dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) renography, and (b) the reproducibility of these parameters. Using renal DCE-MRI and a three-compartment model analysis, this work evaluated the effect two different AIFs, derived from variable sized ROIs in the aorta, has on calculating DCE-MRI renal perfusion and filtration values in a group of healthy adult volunteers who underwent two consecutive renal DCE-MRI studies. METHODS: Fifteen healthy volunteers underwent two DCE-MRI studies under similar physiological conditions. Oblique-coronal DCE-MRI data volumes were acquired on a 1.5 T Siemens Avanto scanner with a 3D-FLASH pulse-sequence (TE/TR=0.53/1.63 ms, flip angle=17 degrees , acquisition matrix=128 x 104 voxels, strong fat saturation, PAT factor=2 (GRAPPA) and 400 mm x 325 mm FOV). Each dynamic dataset consisted of 18 slices of 7.5mm thickness (no gap) and an in-plane resolution of 3.1 mm x 3.1mm, acquired every 2.5s for not less than 5 minutes. During the MR scan a dose of 0.05 m mol (0.1 mL)kg(-1) body weight of dimeglumine gadopentetate (Magnevist) was injected intravenously (2 mLs(-1) injection rate), followed by a 15 mL saline flush at the same rate, using a MR-compatible automated injector (Spectris). Two AIFs were defined for each volunteer by drawing two ROIs in the aorta for each study. Renal perfusion and glomerular filtration rate (GFR) values were then calculated for each of the AIFs using a modified Tofts Renal Model (TRM). Both renal perfusion and GFR were expressed in mL min(-1)100 mL(-1) of tissue. RESULTS AND CONCLUSION: Inter-individual reproducibility tests for renal perfusion and glomerular filtration rate showed that the size of AIF ROIs significantly affects calculated values of perfusion and GFR (p-values <0.02). No significant differences were observed when comparing perfusion and GFR values in the same volunteer between scans performed on different days (p-values >0.22). From our study we conclude that while DCE-MRI derived indices of renal function are reproducible in the same individual when imaged on different days, the size of the aortic ROI and hence the AIF has a significant influence on calculated renal perfusion and GFR values. Currently there is no accepted standard for drawing the aortic ROI and no standardized approach for the AIF definition in renal DCE-MRI studies.

Reproducibility of the aortic input function (AIF) derived from dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) of the kidneys in a volunteer study.

PURPOSE: The aim of this study was to investigate the maximum height, area under the curve (AUC) and full width at half maximum (FWHM) of the aortic input function (AIF) in renal dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) studies. We evaluated the significance of choice of size for regions of interest (ROI) in the aorta, reproducibility and inter-observer agreement of AIF measurements in healthy volunteers for renal DCE-MRI studies. METHODS: Fifteen healthy volunteers (nine males, six females), mean age 28.8 years (range 23-36 years), underwent two DCE-MRI kidney studies under similar conditions. Oblique-coronal DCE-MRI data volumes were acquired on a 1.5 T Siemens Avanto scanner with a 3D-FLASH pulse-sequence (TE/TR=0.53/1.63 ms, flip angle=17 degrees, acquisition matrix=128 x 104 voxels, strong fat saturation, PAT factor=2 (GRAPPA) and 400 mm x 325 mm FOV). Each dynamic dataset consisted of 18 slices of 7.5 mm thickness (no gap) and an in-plane resolution of 3.1 mm x 3.1 mm, acquired every 2.5 s for >5 min. During the MR scan a dose of 0.05 mmol (0.1 mL) kg(-1) body weight of dimeglumine gadopentetate (Magnevist) was injected intravenously (2 mL s(-1) injection rate), followed by a 15 mL saline flush at the same rate, using a MR-compatible automated injector (Spectris). For each DCE-MRI study two observers each drew two ROIs in the abdominal aorta. Both ROIs were 3 voxels in width and had the same inferior limit (just above the emergence of the renal arteries from the aorta) but had different heights (4 voxels for one ROI and 10 voxels for the other). The dimensions, position and time of drawing the ROIs in the dynamic study were standardised between observers prior to data analysis. Mean signal intensities measured in the ROIs were plotted over time, representing the AIF. For each study, AIF 1 was derived from ROI 1 and AIF 2 was derived from ROI 2. RESULTS AND CONCLUSION: Paired t-tests for inter-observer comparison on the pooled 30 DCE-MRI studies, showed good correlations (correlation coefficients >0.85) with no significant differences (p-values >0.82) when comparing the peak value, AUC and FWHM of the AIFs. Thus the results were operator independent. The size of the aortic ROIs significantly affected all measured parameters of the AIF (p-values <0.039). However, correlation coefficients when comparing AIF 1 and AIF 2 were high for all evaluated AIF parameters (correlation coefficients >0.88), indicating a similar shape and temporal dynamic of the passage of the contrast agent through the aorta. When comparing the intra-individual DCE-MRI studies for each volunteer all AIF parameters had p-values >0.22 and correlation coefficients <0.82, with the exception of the FWHM, which had a correlation coefficient of 0.96 showing a significant variation in AIF parameters in the same volunteer on different days.

Evidence for the role of endogenous carbon monoxide in memory processing.

For a decade and a half, nitric oxide (NO) has been implicated in memory processing across a wide variety of tasks and species. Comparatively, endogenously produced carbon monoxide (CO) has lagged behind as a target for research into the pharmacological processes underlying memory formation. This is surprising given that CO is formed in memory-associated brain regions, is structurally similar to NO, and along with NO can activate guanylate cyclase, which is an enzyme well characterized in memory processing. Nevertheless, a limited number of electrophysiological investigations have concluded that endogenous CO is involved in long-term potentiation. Although not evidence for a role in memory per se, these studies did point to the possible importance of CO in memory processing. In addition, there is now evidence to suggest that endogenous CO is important in avoidance learning and possible for other tasks. This review therefore seeks to promote endogenous CO as a potentially important target for memory research.

Inhibition of endogenous carbon monoxide production induces transient retention losses in the day-old chick when trained using a single trial passive avoidance learning task.

Carbon monoxide (CO) is most often thought of as an exogenous toxin rather than as a possible endogenous nootrope. However, a limited number of studies have suggested that CO is necessary in memory processing for at least some tasks. While nitric oxide (NO) and CO are known activators of guanylyl cyclase (GC), only the effect of NO on GC has been extensively investigated as a mechanism underlying memory processing. The aim of the present study was to determine if inhibition of CO production would have an effect on memory processing. Using chicks trained on a single trial passive avoidance task, inhibition of CO production using zinc (II) deuteroporphyrin IX 2,4-bis ethylene glycol (ZnBG; 5 microM) resulted in two transient retention losses occurring at around 40 and 130 min post-training. The timing of these transient retention losses was similar to those observed following inhibition of GC, using the same species and task in a previous study. This supports the notion that CO is necessary in memory processing for this task and may act through a GC-dependent mechanism. As ZnBG also directly inhibits GC or nitric oxide synthase (NOS) at high concentrations, a second experiment was carried-out to confirm the specificity of ZnBG for heme oxygenase (HO) at the concentration used. The action of ZnBG was challenged with the HO agonist hemin (100 microM) and the transient deficits were abolished. This confirmed that the action of ZnBG on memory was through a CO-related mechanism rather than directly on GC or NOS. In this way the specificity of ZnBG (5 microM) for HO could be confirmed. The results support a role for endogenous CO in memory processing, possibly through activation of GC. In addition, the transient retention losses observed following administration of ZnBG suggest that CO may be necessary for memory retrieval and not formation as previously thought.

Relationship between total and allergen-specific IgE serum levels and presence of symptoms in farm workers sensitized to Tetranychus urticae.

BACKGROUND: Clinical complaints in atopic subjects with asthma and rhinitis occur more frequently in the presence of high total and allergen-specific IgE serum levels. Here we report on the relationship between total and allergen-specific IgE serum levels and presence of symptoms in an unselected farmer population sensitized to Tetranychus urticae (TU). METHODS: Farmers were recruited as previously described. Total IgE and allergen-specific IgE were measured by immunoassay in TU-positive skin prick test (SPT) farmers (n = 58) and two control groups including Dermatophagoides pteronyssinus (Dp)-positive SPT subjects (n = 40) and non-atopic, TU-negative SPT healthy farmers (n = 25). RESULTS: Both TU+ and Dp+ subjects had significantly higher total IgE values (P < 0.001) than healthy non-atopic subjects. TU-specific IgE levels were significantly more elevated in symptomatic than non-symptomatic TU+ subjects (P = 0.028). Dp-specific IgE levels were higher in symptomatic than non-symptomatic Dp+ subjects (P = 0.003). Finally, total IgE levels were significantly higher in the symptomatic than non-symptomatic subgroups in both TU+ and Dp+ subjects (P < 0.0001 and P = 0.007, respectively). Logistic regression analysis showed that only total IgE concentrations were significant predictors of current symptoms in TU+ subjects. CONCLUSIONS: High total IgE and allergen-specific IgE levels are associated with symptoms in TU+ subjects. Definition of their predictive value requires further studies.

Long-term absence of sensitization to mepivacaine as assessed by a diagnostic protocol including patch testing.

BACKGROUND: Prospective assessment of non-reactivity to local anaesthetics is a frequent reason for allergy consultation. OBJECTIVES: To investigate the clinical profiles of subjects referred for allergy evaluation; to prospectively reduce the frequency of evaluation by assessing the persistence, during clinical use, of non-reactivity to contaminant/additive-free mepivacaine; and to determine the usefulness of a diagnostic protocol involving patch testing. METHODS: In a prospective study, 198 consecutive patients underwent collection of clinical data, skin prick tests and patch tests using allergens/antigens relevant for the investigation, and an intradermal/subcutaneous challenge procedure using contaminant/additive-free mepivacaine, as appropriate. Patients were followed up for 3 years for assessment of non-reactivity persistence using the same diagnostic protocol. RESULTS: Only one-third of the patients had a history of previous adverse local anaesthetic reactions. Absence of sensitization to contaminant/additive-free mepivacaine persisted in all subjects completing the follow-up. Controlled challenge with mepivacaine was negative in 196 patients with both negative specific skin prick tests and patch tests but it was eventful in two subjects with positive specific patch tests. A few subjects displayed positive skin prick tests and/or patch tests for latex and/or additives. CONCLUSIONS: A few patients had a relevant history for potential local anaesthetic-induced adverse reactions. Upon assessment of absence of sensitization and reactivity, contaminant/additive-free mepivacaine could safely be given for as long as 3 years. The patch testing was shown to be useful and safe for prediction of challenge outcomes. True allergic reactions to contaminant/additive-free mepivacaine were not observed in our patient series.

Gastroesophageal reflux disease and asthma: an intriguing dilemma.

BACKGROUND: Gastroesophageal reflux disease (GORD) is characterized by typical reflux symptoms and multiple atypical extraesophageal symptoms. Gastric asthma is a prominent extraesophageal manifestation of GORD. There is persistent debate about the pathophysiologic mechanisms triggering asthma by GOR. METHODS: We conducted a review of the literature. RESULTS: The pathogenic mechanism could be either a vagally transmitted reflex or an intratracheal aspiration of refluxed material. In both hypotheses, the role of inflammatory mediators has been proposed. CONCLUSIONS: Neurogenic inflammation is a good theoretic basis for a pathogenic interpretation of the disorder. In atopic patients, food allergy has been recently proposed as a possible cause of GOR and associated respiratory symptoms, and it should be considered in the diagnostic work-up of all patients with GORD.