Information technology systems to support antimicrobial stewardship programs

Problem

Inappropriate antibiotic use contributes to the emergence and spread of multidrug-resistant organisms that are responsible for life-threatening infections. Furthermore, overprescription of antibiotics is associated with an increased risk of adverse effects and higher costs.

Description of the problem

Careggi is a tertiary care teaching hospital in Italy, with nearly 1,200-bed units, involved since 2015 in antimicrobial stewardship (AMS) programs. Despite implementation programs, carbapenems (CAR) consumption rates remained higher than the national average; for this reason, the AMS hospital team started a project aimed at improving the appropriateness of this type of drug.

Results

The project started in October 2021 and involved 10 hospital Units selected as the major prescribers of CAR. The strategies were planned by a multi-professional and multi-disciplinary team of experts in AMS and were set in place by a multimodal approach focused on information technology (IT) functions implemented in the electronic medical record such as:

• time-out alerts at 72 hours inviting physicians to evaluate if the prescribed antimicrobial is still warranted or effective against the identified organism(s);

• interactive and customizable prescribing algorithms to support physicians in empirical and targeted therapies;

• electronic dashboards viewable by physicians and the AMS team to daily monitor and review CAR prescriptions.

These functions were complemented by a series of training sessions for prescribing physicians aimed to promote a more rational and appropriate antimicrobials use. Six months after the project began, an overall reduction in the prescription of CAR was observed: from 6.2 DDD/100 patient-days to 4.9 DDD/100 patient-days.

Lessons

AMS programs use different interventions to influence the behavior of prescribers toward more appropriate use of antimicrobials. IT functions represent complementary and useful tools to promote antimicrobial stewardship programs.

Key messages

• Antimicrobial stewardship programs aim at optimizing antibiotic use and reducing inappropriate antibiotic prescriptions.

• Information technology systems represent useful tools within AMS programs.

The management of NDM-β-lactamase-producing carbapenem-resistant Enterobacterales in Tuscany

Issue

An important outbreak of New Delhi metallo-β-beta-lactamase (NDM)-producing carbapenem-resistant Enterobacterales (CRE) has been reported from north-western of Tuscany since November 2018. NDM is a metallo-β-lactamase able to hydrolyze most β-lactames (including carbapenems) with limited treatment options.

Description of the Problem

From November 2018 to May 2019, 7 Tuscan hospitals notified a total of 350 infected or colonized cases. This outbreak was described in a risk assessment edited by the European Centre for Disease Prevention and Control (ECDC) in June 2019. The Ministry of Health and the Tuscany Region promptly adopted infection prevention control measures.

Results

Since July 2019, a regional task force, composed by experts in infectivology, microbiology and public health, coordinated the following actions: Publication of Regional Resolutions which have established practical guidelines for the outbreak management. These measures included:(I) the introduction of screening test for CRE by rectal swab for hospitalized patients; (II) the implementation of microbiological rapid molecular tests and genotyping of rectal swab; (III) the enhancement of standard and transmission-based precautions; (iv) the strengthening of handover between hospital setting and primary healthcare; (v) the implementation of a regional data-base for outbreak surveillance.Monthly regional meetings with the infection control teams of each hospital.Site visits (n. 44) performed by a group of experts in all healthcare facilities.

After the implementation of these measures, a trend for decrease in positive blood cultures of NDM was registered.

Lessons

The spread of NDM in Tuscany has been the opportunity to standardize and improve the approach to Multidrug-Resistant Organisms (MDROs) prevention and control.

Key messages

The spread of NDM in Tuscany has been the opportunity to standardize and improve the approach to Multidrug-Resistant Organisms (MDROs) prevention and control. The cooperation among stakeholders and the standardization of precaution measures and healthcare workers’ behavior allows to effectively face the MDROs diffusion.

Trichilemmal cystis in metastatic melanoma: a case report

The malignant melanoma is a neoplasm associated with a wide variety of cutaneous paraneoplastic syndromes, as dermatomyositis, systemic sclerosis, paraneoplastic pemphigus. We describe a case of four multiple trichilemmal cystis arising on frontal region in the same patient with brain metastasis and unknown primary melanoma and discuss their relationship.

W+ W- production at hadron colliders in next to next to leading order QCD

Charged gauge boson pair production at the Large Hadron Collider allows detailed probes of the fundamental structure of electroweak interactions. We present precise theoretical predictions for on-shell W+ W- production that include, for the first time, QCD effects up to next to next to leading order in perturbation theory. As compared to next to leading order, the inclusive W+ W- cross section is enhanced by 9% at 7 TeV and 12% at 14 TeV. The residual perturbative uncertainty is at the 3% level. The severe contamination of the W+ W- cross section due to top-quark resonances is discussed in detail. Comparing different definitions of top-free W+ W- production in the four and five flavor number schemes, we demonstrate that top-quark resonances can be separated from the inclusive W+ W- cross section without a significant loss of theoretical precision.

Oestrogen receptor beta and melanoma: a comparative study

BACKGROUND

Oncological research has focused on evaluating oestrogen receptors (ERs) in oestrogen-related tumours, and understanding the potential role of ERs in the pathophysiology of cancer.

OBJECTIVES

To investigate the significance of oestrogen receptor beta (ERβ) in melanoma.

METHODS

We prospectively evaluated ERβ expression in malignant melanoma (MM) tissue and adjacent healthy skin by quantitative immunohistochemistry at the Department of Dermatology of the University of Florence, from 1998 to 2010.

RESULTS

ERβ was detected with varying staining intensity in the 66 malignant melanocytic lesions. After adjusting for age and sex, we found that ERβ expression was significantly lower in melanoma tissue compared with adjacent healthy skin (P < 0·0001). We also found significantly lower ERβ levels in thick melanoma tissue compared with thin melanoma tissue. In addition, there was a positive association between Breslow thickness and the difference of ERβ expression between healthy tissue and melanoma tissue (P = 0·0004). Consistent with sex differences in melanoma survival, men showed significantly lower levels of ERβ than women in both melanoma (P = 0·05) and healthy tissues (P = 0·02).

CONCLUSIONS

ERβ expression is inversely associated with Breslow thickness and is significantly influenced by sex in MM.

Multiple primary melanoma: the impact of atypical naevi and follow up

BACKGROUND

Patients with melanoma are especially encouraged to have regular follow- up visits with their dermatologist and to perform total-body skin examination on a routine basis to identify new pigmented lesions or detect significant changes in existing naevi.

OBJECTIVES

To identify main risk factors (sex, age, number of common and atypical naevi, family history, phototype) associated with multiple primary melanomas (MPM) and to investigate the association between regular follow up and tumour thickness of a second primary melanoma.

METHODS

We performed a retrospective analysis of patients with MPM in order to evaluate risk factors for developing a second primary melanoma. Medical records of patients with melanoma who developed a second primary melanoma were selected from a database of all patients with histopathologically confirmed melanoma treated at the dermatology clinic of the University of Florence, Italy, from 2000 to 2004. Medical data culled from the patient records were as follows: medical history, number of typical naevi, presence of atypical naevi, Breslow thickness, Clark level and histotype of the melanomas, site of the melanomas and patient adherence to 6-month follow-up examinations.

RESULTS

The presence of atypical naevi was associated with a higher risk of developing MPM (adjusted odds ratio 3·28, 95% confidence interval 1·35–7·44). Moreover, in the subjects who did not attend follow up, we noted that the thickness of the second melanoma was significantly higher, with a mean thickness of 1·22 mm, in comparison with patients with a careful adherence to follow up in whom the mean thickness was 0·36 mm (P = 0·0189).

CONCLUSIONS

For the first time, the validity of this clinical approach has been supported by real comparison of thickness levels of second melanoma in patients with or without periodical follow up. Results obtained from this analysis show that follow up is an effective method for early detection of melanoma.

Photodynamic treatment for viral infections of the skin

Photodynamic therapy (ALA/MAL-PDT) is indicated for the treatment of actinic keratoses, for superficial, nodular basal cell carcinoma and for Bowen's disease; there is evidence that PDT can be active also against bacteria, viruses and fungi. The new indications for PDT include many types of viral skin infections human papilloma virus (HPV)-related as verrucae of feet and hands, Condylomata acuminata, periungueal warts, epidermodysplasia verruciformis, but also viral skin lesions non HPV related as molluscum contagiosum and herpes simplex can be successfully treated. The use of PDT in HPV infections is due to its anti-inflammatory and antiproliferative skills: in the lesions treated there is a release of cytotoxic radicals which damage keratinocytes infected by HPV, inducing their selective apoptosis and necrosis. The PDT application in this field of lesions is safe and successful; in comparison with the other techniques it has less side-effects and less recurrences, but the most important property is that it is not-invasive: it means a reduced risk of infections and excellent cosmetic results.

Chest wall kinematics, respiratory muscle action and dyspnoea during arm vs. leg exercise in humans

AIM

We hypothesize that different patterns of chest wall (CW) kinematics and respiratory muscle coordination contribute to sensation of dyspnoea during unsupported arm exercise (UAE) and leg exercise (LE).

METHODS

In six volunteer healthy subjects, we evaluated the volumes of chest wall (V(cw)) and its compartments, the pulmonary apposed rib cage (V(rc,p)), the diaphragm-abdomen apposed rib cage (V(rc,a)) and the abdomen (V(ab)), by optoelectronic plethysmography. Oesophageal, gastric and trans-diaphragmatic pressures were simultaneously measured. Chest wall relaxation line allowed the measure of peak rib cage inspiratory muscle, expiratory muscle and abdominal muscle pressures. The loop V(rc,p)/V(rc,a) allowed the calculation of rib cage distortion. Dyspnoea was assessed by a modified Borg scale.

RESULTS

There were some differences and similarities between UAE and LE. Unlike LE with UAE: (i) V(cw) and V(rc,p) at end inspiration did not increase, whereas a decrease in V(rc,p) contributed to decreasing CW end expiratory volume; (ii) pressure production of inspiratory rib cage muscles did not significantly increase from quiet breathing. Not unlike LE, the diaphragm limited its inspiratory contribution to ventilation with UAE with no consistent difference in rib cage distortion between UAE and LE. Finally, changes in abdominal muscle pressure, and inspiratory rib cage muscle pressure predicted 62% and 41.4% of the variability in Borg score with UAE and LE, respectively (P < 0.01).

CONCLUSION

Leg exercise and UAE are associated with different patterns of CW kinematics, respiratory muscle coordination, and production of dyspnoea.

Understanding dyspnoea by its language

Dyspnoea is a general term used to characterise a range of qualitatively distinct descriptors that vary in intensity. Based on the hypothesis that various qualities of respiratory discomfort result from different pathophysiological abnormalities, language could help to define one or more of the abnormalities responsible for breathing discomfort. The use of descriptors of dyspnoea may contribute to the understanding of the mechanisms of dyspnoea, and assist in identifying or predicting a specific diagnosis. Symptoms that can be reliably discriminated imply different pathophysiological mechanisms, whereas symptoms that cannot be reliably discriminated imply similar pathophysiological mechanisms. Since dyspnoea is a fundamental part of patient's clinical history, physicians should become more fluent in the language of dyspnoea.

Measures of perception of bronchoconstriction and clinical and functional data are not interrelated in asthma

BACKGROUND

Sensitivity and absolute perceptual magnitude characterize the perception of bronchoconstriction (PB).

OBJECTIVES

To define whether clinical and functional characteristics and level of bronchial hyperresponsiveness (BHR) correlate with these two PB indexes during bronchial challenge in asthma.

METHODS

PB on both the Borg scale and the visual-analogue scale (VAS) was assessed in 45 consecutive asthmatics during a methacholine-induced decrease in forced expiratory volume in 1 s (FEV(1)) and specifically quantified as Borg and VAS slope, as a measure of sensitivity, whereas scores at a 20% FEV(1) decrease (PB(20)) were assessed as a measure of absolute perceptual magnitude. Clinical score and BHR were also assessed.

RESULTS

PB(20) related to slope on both the Borg scale and the VAS (p < 0.0001). PB(20) and slope related neither to clinical score nor to baseline functional data on both scales. The relationship between the level of BHR and PB(20) on either scale was of questionable clinical significance (r(2) = 7%).

CONCLUSIONS

Irrespective of the scale employed, our data indicate the need for directly assessing PB rather than deriving it from clinical and functional data and level of BHR.

The diaphragm and dyspnea during chemically stimulated breathing in a subset of patients with diabetes

In patients with insulin-dependent diabetes mellitus (IDDM) isolated peripheral airway involvement may give rise to inspiratory threshold load (ITL) contributing to dyspnea. Based on the reported evidence of a greater increase in end-expiratory lung volume (EELV) with hypoxia than with hypercapnia in IDDM, we wondered whether, and to what extent in the two conditions, EELV contribute to perception of dyspnea (PD). We studied five nonsmokers aged between 19 and 45, with IDDM under good metabolic control and five normal control subjects matched for age. In each patient, we evaluated the electromyographic activity of the diaphragm (Edi), the swings of esophageal (Pessw), gastric (Pgsw), and transdiaphragmatic (Pdisw = Pgsw-Pessw) pressures; PD was assessed by a modified Borg scale during hypercapnic-hyperoxic (HCH) and hypoxic-isocapnic (HIC) stimulation. Change in inspiratory capacity (IC) was considered the mirror image of increase in EELV, that is, dynamic hyperinflation (DH), while intrinsic positive end inspiratory pressure (PEEPi) was measured as an index of inspiratory threshold load (ITL). In controls, Edi and Pdi but not their ratio (Edi/Pdi) related to Borg. In patients the following was found: (1) with each of the two stimuli, for any given Edi, Pdi, and Edi/Pdi ratio, there was greater Borg than in controls, (2) a similar increase in ITL and DH with HCH and HIC, (3) Edi/Pdi related to Borg similarly with HCH as with HIC. In conclusion, in controls, Edi and Pdi were associated with the perception of dyspnea similarly with the two chemical stimuli. In this subset of patients with IDDM, Edi/Pdi ratio throughout increase in EELV and ITL was found to affect the perception of dyspnea in hypoxia to a similar extent as in hypercapnia.

Perception of bronchoconstriction in smokers with airflow limitation

To our knowledge, no data have been provided as to whether and to what extent dynamic hyperinflation, through its deleterious effect on inspiratory muscle function, affects the perception of dyspnoea during induced bronchoconstriction in patients with chronic airflow obstruction. We hypothesized that dynamic hyperinflation accounts in part for the variability in dyspnoea during acute bronchoconstriction. We therefore studied 39 consecutive clinically stable patients whose pulmonary function data were as follows (% of predicted value): vital capacity (VC), 97.8% (S.D. 16.0%); functional residual capacity, 105.0% (18.8%); actual forced expiratory volume in 1 s (FEV(1))/VC ratio, 56.1% (6.3%). Perception of dyspnoea using the Borg scale was assessed during a methacholine-induced fall in FEV(1). The clinical score and the treatment score, the level of bronchial hyper-responsiveness and the cytological sputum differential count were also assessed. In each patient, the percentage fall in FEV(1) and the concurrent Borg rating were linearly related, with the mean slope (PD slope) being 0.09 (0.06). The percentage fall in FEV(1) accounted for between 41% and 94% of the variation in the Borg score. At a 20% fall in FEV(1), the decrease in inspiratory capacity (Delta IC) was 0.156 (0.050) litres. Patients were divided into three subgroups according to the PD slope (arbitrary units/% fall in FEV(1)): subgroup I [eight hypoperceivers; PD slope 0.026 (0.005)], subgroup II [26 moderate perceivers; 0.090 (0.037)] and subgroup III [five hyperperceivers; 0.200 (0.044)]. By applying stepwise multiple regression analysis with the PD slope as the dependent variable, and other characteristics (demographic, clinical and functional characteristics, smoking history, level of bronchial hyper-responsiveness and sputum cytological profile) as independent variables, Delta IC (r(2)=45%, P<0.00001) and to a lesser extent treatment score (r(2)=17.3%, P<0.0006), and to an even lesser extent age (r(2)=3%, P<0.05), independently predicted a substantial amount (r(2)=65.27%, P<0.00001) of the variability in the Borg slope. Thus acute hyperinflation, and to a lesser extent treatment score and age, account in part for the variability in the perception of dyspnoea after accounting for changes in FEV(1) during bronchoconstriction in patients with chronic airflow obstruction.

Do inhaled corticosteroids affect perception of dyspnea during bronchoconstriction in asthma?

BACKGROUND

Some of the disagreements on the perception of dyspnea (PD) during bronchoconstriction in asthma patients could depend on the interrelationships among the following: (1) the influence of baseline airflow obstruction on the patient's ability to detect any further increase in airway resistance; (2) the effect of eosinophilic inflammation on the airway; (3) bronchial hyperresponsiveness (BHR); and (4) the effect of inhaled corticosteroids (ICSs).

OBJECTIVE

We hypothesized that if the inflammation of the airway wall influences to some extent and in some way the PD in asthma patients, ICSs reverse the effect of airway inflammation on the PD.

METHODS

We studied 100 asthma patients who were divided into the following four groups: patients with obstruction who were either ICS-naive (group I) or were treated with ICSs (group II); and nonobstructed patients who were either ICS-naive (group III) or were treated with ICSs (group IV). PD on the visual analog scale (VAS) was assessed during a methacholine-induced FEV(1) decrease and specifically was quantified as the VAS slope and score at an FEV(1) decrease of 5 to 20%. BHR was assessed in terms of the provocative concentration of methacholine causing a 20% fall in FEV(1) (PC(20)). Eosinophil counts in induced sputum samples also were performed. Regression analysis, univariate analysis of variance, and factor analysis were applied for statistical evaluation.

RESULTS

For a 5 to 20% fall in FEV(1) from the lowest point after saline solution induction, VAS score was lowest in group II, slightly higher in group I, slightly higher still in group IV, and the highest in group III. In the patients as a whole, BHR related to PD, but age, clinical score, duration of the disease, and presence of baseline airway obstruction did not. In patients with obstruction who were treated with ICSs, eosinophil counts related to PD negatively. Factor analysis yielded the following four factors that accounted for 70% of the variance in the data: ICS; eosinophil counts; FEV(1); and PC(20) loaded on separated factors with PD loading on the same factors as PC(20). The post hoc analysis carried out dividing the patients into ICS-treated and ICS-naive, showed that in the former group eosinophil counts and BHR proved to be factors negatively associated with PD, while in the latter group eosinophil counts were positively associated with PD.

CONCLUSIONS

We have shown that eosinophilic inflammation of the airway wall may increase PD and that the association of eosinophil counts with ICSs may result in lessening the PD.

Relevance of dyspnoea and respiratory function measurements in monitoring of asthma: a factor analysis

Previous studies in patients with stable chronic obstructive pulmonary disease have demonstrated that objective measures (lung volumes and respiratory muscle force) and clinical or subjective measures (symptoms of breathlessness and exercise tolerance) are quantities that independently characterize the conditions of these patients. Such an evaluation has not been previously applied in patients with stable bronchial asthma. Sixty-nine patients with stable chronic asthma underwent evaluation of static (functional residual capacity, FRC) and dynamic [forced expiratory volume in 1 sec (FEV1) and forced vital capacity, FVC] lung volumes; respiratory muscle strength (RMS), by measuring maximal inspiratory and expiratory pressures, and exercise capacity by means of the 6-min walking distance (6MWD). Chronic exertional dyspnoea was assessed by the Baseline Dyspnoea Index (BDI) focal score and by the Medical Research Council (MRC) scale. Statistical evaluation was performed by applying factor analysis. Three factors accounted for 78% of the total variance in the data: FEV1, FVC loaded on a factor I; RMS, FRC and 6MWD loaded on a factor II; dyspnoea ratings loaded on a factor III. Post-hoc analysis by randomly dividing the patients into two subgroups gave the same results. In asthmatic patients, airway obstruction appeared as an independent dimension or factor. Dyspnoea independently characterized the condition of asthma. Submaximal exercise tolerance could not be associated with the symptom of breathlessness. Evidence of independent factors support the validity of routine, multi-factorial assessment and the primary goal of treatment to alleviate symptoms and improve functional capacity in stable asthmatics.

Mechanisms involved in airway obstruction: the role of smooth muscle

Structural changes in the airway walls that are probably driven by mediators released as a consequence of chronic allergic inflammation are prominent features of asthma. However, it is not clear how each of the many changes that occur in the airway wall contribute to altered airway function in asthma. Collagen deposition in the subepithelial matrix, around and inside the smooth muscle, would be expected to oppose the effect of smooth-muscle contraction. Conversely, geometric factors would result in exaggerated airway narrowing for a given degree of smooth-muscle shortening; decreased airway wall stiffness and increased airway narrowing for a given amount of force generated by the smooth muscle. Degradation of the matrix may alter the coupling between muscle and lung recoil, allowing exaggerated smooth-muscle shortening. Increase in muscle mass associated with preservation of its contractile capacity could be the most important contributor to exaggerated airway narrowing.

Pharmacological treatment of exercise dyspnoea

A better understanding of the mechanisms of dyspnoea improves the clinician's ability to treat patients with shortness of breath. Any intervention that: 1) reduces ventilatory demands; 2) reduces ventilatory impedance; or 3) improves inspiratory muscle function, may relieve dyspnoea. Reduced ventilatory demand may be obtained by reducing metabolic load. Supplemental oxygen during exercise reduces exertional breathlessness and improves exercise tolerance, the decrease in dyspnoea being proportional to decrease in minute ventilation. Reduced ventilatory demand may also be obtained by decreasing the central drive. Opiates have been shown to decrease minute ventilation at rest and during submaximal exercise. They can alter the central processing of neural signals within the central nervous system to reduce sensations associated with breathing. Contrastingly, no consistent improvement in dyspnoea (versus placebo) has been shown with anxolytics. Decreasing central drive may also be obtained by altering pulmonary afferent information. Interventions that alter transmittal of afferent information to the central controller, potentially reduce dyspnoea. Reduction of ventilatory impedance is obtained by administering B2, anticholinergics or theophylline. B2 and anticholinergics act by modulating the increase in operational lung volumes and the inspiratory muscle effort during exercise. The mechanism by which theophylline relieves dyspnoea is probably related to a mechanism other than its bronchodilation alone. Alterations in respiratory muscle function are currently being detected in patients with chronic obstructive pulmonary disease, due to alteration in respiratory muscle energy balance. Nutritional repletion may improve respiratory muscle function but uncertainty remains as to whether nutritional repletion may relieve dyspnoea. The cumulative benefit of interventions targeting the pathophysiologic mechanism of dyspnoea must be identified for optimum treatment of patients with shortness of breath.

Next-to-next-to-leading-order logarithmic corrections at small transverse momentum in hadronic collisions

We study the region of small transverse momenta in q&qmacr;- and gg-initiated processes with no colored particle detected in the final state. We present the universal expression of the O(alpha(2)(s)) logarithmically enhanced contributions up to next-to-next-to-leading-order logarithmic accuracy. From there we extract the coefficients that allow the resummation of the large logarithmic contributions. We find that the coefficient known in the literature as B((2)) is process dependent, since it receives a hard contamination from the one-loop correction to the leading-order subprocess. We present the general result of B((2)) for both quark and gluon channels.

Perception of bronchoconstriction and bronchial hyper-responsiveness in asthma

The inter-relationship between the perception of bronchoconstriction, bronchial hyper-responsiveness and temporal adaptation in asthma is still a matter of debate. In a total of 52 stable asthmatic patients, 32 without airway obstruction ¿forced expiratory volume in 1 s (FEV(1))/vital capacity (VC) 84.1% (S.D. 7.9%), and 20 with airway obstruction [FEV(1)/VC 60% (4%)], we assessed the perception of bronchoconstriction during methacholine inhalation by using: (i) the slope and intercept of the Borg and VAS (Visual Analog Scale) scores against the decrease in FEV(1), expressed as a percentage of the predicted value; and (ii) the Borg and VAS scores at a 20% decrease in FEV(1) from the lowest post-saline level (PB(20)). Bronchial hyper-responsiveness was assessed as the provocative concentration of methacholine causing a 20% fall in FEV(1) (PC(20)FEV(1)). The reduction in FEV(1) was significantly related to the Borg and VAS scores, with values for the group mean slope and intercept of this relationship of 0.13 (S.D. 0.08) and -1.1 (3.02) for Borg, and 1.5 (1.19) and -12.01 (35) for VAS. PB(20) was 3 (1.75) with Borg scores and 34.6 (20.5) with VAS scores. Compared with the subgroup without airway obstruction, the obstructed subgroup exhibited similar slopes, but lower Borg and VAS intercepts. For similar decreases in FEV(1) (5-20% decreases from the lowest post-saline values), the Borg and VAS scores were lower in the non-obstructed than in the obstructed subgroup. PC(20)FEV(1) was significantly related to both Borg PB(20) and VAS PB(20) when considering all patients. When assessing the subgroups, PC(20)FEV(1) was related to Borg PB(20) and VAS PB(20) in the non-obstructed subjects, but not in the obstructed subjects. In neither subgroup was the log of the cumulative dose related to the Borg and VAS scores at the end of the test. We conclude that, unlike in previous studies, the ability to perceive acute bronchoconstriction may be reduced as background airflow obstruction increases in asthma. Bronchial hyper-responsiveness did not play a major role in perceived breathlessness in patients without airway obstruction, and even less of a role in patients with obstruction. The cumulative dose of agonist did not appear to influence the perception of bronchoconstriction.

Diagnostic accuracy of sputum outcomes in chronic stable asthma

BACKGROUND

Asthma with non-remitting airflow obstruction may not always be differentiated from COPD with airway hyperreactivity. Many attempts have been made to find useful markers for the distinction between these two disorders.

OBJECTIVE AND METHODS

In order to help the finding of a useful marker for the diagnosis of asthma in the population of patients with airway obstruction we analysed the diagnostic accuracy of sputum eosinophils and sputum ECP in 91 patients with asthma, 15 patients with chronic bronchitis, 32 patients with chronic obstructive pulmonary disease (COPD) and 20 controls subjects, by performing ROC analysis.

RESULTS

Sputum eosinophils were above the normal range of our laboratory (0-3.7%) in 48 asthma patients and in six COPD patients, while sputum ECP (normal range < 85 microg/L) was high in 65 asthma patients, in 24 COPD patients and in nine chronic bronchitis patients. The ROC analysis revealed that sputum eosinophils count (AUC = 0.82) was more accurate than both sputum ECP levels (AUC = 0.56) (P < 0.0001) and beta2-reversibility (AUC = 0.53) (P = 0.0001) in differentiating asthmatic from non-asthmatic subjects (COPD, chronic bronchitis patients and normal subjects). The diagnostic accuracy of ECP was similar to that of bronchial reversibility (P = 0.76). When ROC analysis was performed by including only patients with airway obstruction (36 asthmatics with airway obstruction and COPD patients), both eosinophil count (AUC = 0.77) and beta2-reversibility (AUC = 0.66) were more accurate than ECP measurement (AUC = 0.39) in discriminating asthmatics from COPD patients (P < 0.00001 and P = 0.04, respectively).

CONCLUSION

Sputum eosinophils seem to be valid markers for detecting asthma in a population of patients with airway obstruction. Moreover, the higher diagnostic accuracy of eosinophils in the sputum compared to sputum ECP and bronchial reversibility reinforces the role of cytological analysis of sputum in the diagnosis of chronic stable bronchial asthma.

Reduction in bronchodilation following a deep inhalation is poorly related to airway inflammation in asthma

In patients with bronchial asthma, forced expiratory flows are differently sensitive to a previous volume history. A reduced ability of a deep inhalation (DI) to dilate obstructed airways has been hypothesized to be a physiological marker for the degree of airway responsiveness and to relate to the presence and magnitude of inflammation in the lung, even in mild stable asthma. However, there are at present doubts as to whether functional changes could be used as a substitute for airway inflammation studies. In order to investigate the interrelations among airway inflammation, bronchial hyperresponsiveness and effects of volume history, 58 consecutive asthmatics with mild to moderate asthma were studied. The effects of DI were assessed as the isovolumic ratio of flows from forced expiratory manoeuvres started from maximal (M) or partial (P) lung inflation. Airway inflammation was assessed by using induced sputum. Sputum was analysed for total and differential cell counts, and levels of eosinophil cationic protein (ECP) which reflects eosinophil activation. Airway responsiveness was assessed as the provocative concentration of histamine which caused a 20% fall in forced expiratory volume in one second (FEV1) from control (PC20). The M/P ratio was significantly related to ECP (r=-0.31, p<0.03) and eosinophils (r=-0.29, p<0.03), FEV1/vital capacity (VC) (r=0.32; p<0.01), clinical score (r=-0.33; p<0.03) and age (r=-0.41; p<0.0001). In a stepwise multiple regression analysis including age, score, baseline lung function, ECP, number of eosinophils and the response to beta2-agonist, age (p<0.037) predicted a small amount of the variance in M/P ratio (r2=0.12). It is concluded that volume history response is substantially independent of both sputum outcomes (inflammatory cell number and eosinophil cationic protein) and bronchial hyperresponsiveness; rather it seems to be associated with anthropometric characteristics. Functional aspects do not provide information on eosinophilic, probably central, airway inflammation.

Sputum analysis, bronchial hyperresponsiveness, and airway function in asthma: results of a factor analysis

BACKGROUND

Recent studies have shown weak associations among FEV1, bronchial hyperresponsiveness (BHR), sputum eosinophils, and sputum eosinophil cationic protein (ECP), suggesting that they are nonoverlapping quantities. The statistical method of factor analysis enables reduction of many parameters that characterize the disease to a few independent factors, with each factor grouping associated parameters.

OBJECTIVE

The purpose of this study was to demonstrate, by using factor analysis, that reversible airway obstruction, BHR, and eosinophilic inflammation of the bronchial tree, as assessed by cytologic and biochemical analysis of sputum, may be considered separate dimensions that characterize chronic bronchial asthma.

METHODS

Ninety-nine clinically stable patients with a previous diagnosis of asthma underwent spirometry, sputum induction, and histamine inhalation tests.

RESULTS

Most patients were nonobstructed (FEV1, 91% +/- 20%); a low level of bronchial reversibility (FEV1 increase after beta2 -agonist, 7.8% +/- 9.2%) and BHR (histamine PC20 FEV1 geometric mean, 0.98 mg/mL) were found. Sputum eosinophil differential count (12.4% +/- 17.7%) and sputum ECP (1305 +/- 3072 microg/mL) were in the normal range of our laboratory in 38 and 22 patients, respectively. Factor analysis selected 3 different factors, explaining 74.8% of variability. Measurements of airway function and age loaded on factor I, PC20 FEV1 and beta2 -response loaded on factor II, and sputum ECP and eosinophils loaded on factor III. Additional post hoc factor analyses provided similar results when the sample was divided into 2 subgroups by randomization, presence of airway obstruction, degree of BHR, percentage of sputum eosinophils, or concentration of sputum ECP.

CONCLUSIONS

We conclude that airway function, baseline BHR, and airway inflammation may be considered separate dimensions in the description of chronic asthma. Such evidence supports the utility of routine measurement of all these dimensions.

Chronic exertional dyspnea and respiratory muscle function in patients with chronic obstructive pulmonary disease

The symptom of breathlessness is an important outcome measure in the management of patients with chronic obstructive pulmonary disease (COPD). Clinical ratings of dyspnea and routine lung function are weakly related to each other. However, in the clinical setting breathlessness in COPD is encountered under conditions of increased respiratory effort, impeded respiratory muscle action, or functional weakness. Thus, the present study was carried out to determine whether and to what extent clinical ratings of dyspnea and respiratory muscle dysfunction relate to each other. In 21 patients with COPD two methods were used to rate dyspnea: a modified Medical Research Council Scale (MRC) and the Baseline Dyspnea Index (BDI), which is a multidimensional instrument for measuring dyspnea based on three components: magnitude of task, magnitude of effort, and functional impairment. A baseline focal score was obtained as the sum of the three components. Measures were: pulmonary volumes; arterial blood gases; maximal voluntary ventilation (MVV); maximal inspiratory and expiratory pressures (MIP and MEP, respectively); and breathing patterns ventilation (VE), tidal volume (VT), and respiratory frequency (Rf). In 15 patients pleural pressure was also measured during both quiet breathing (Pplsw) and maximal inspiratory sniff maneuver at FRC (Pplsn). BDI and MRC ratings related to each other and showed comparable weak associations with standard parameters (FEV1, PaCO2, VT), MIP, and MEP. In contrast, MVV closely and similarly related to both ratings. Pplsw (%Pplsn), a measure of respiratory effort, and Pplsw (%Pplsn)/VT(%VC), an index of neuroventilatory dissociation, related significantly to both the BDI (r2 = -0.77 and r2 = -0.75, respectively) and the MRC (r2 = 0.81 and r2 = 0.74, respectively). Using MVV, Pplsw (%Pplsn), and Pplsw (%Pplsn)/VT(%VC) in a stepwise multiple regression as independent variables with BDI rating as dependent variable, MVV explained an additional 14.5% of the variance of the BDI over the 67.8% predicted by Pplsw (%Pplsn). Our results demonstrate that the level of chronic exertional dyspnea in COPD increases as the ventilatory muscle derangement increases. The level of the relationships among dyspnea ratings and MVV and respiratory effort helps to explain some of the mechanisms of chronic dyspnea of COPD. These measures should be considered for therapeutic intervention to reduce dyspnea.

[Overdosing on diltiazem in heptic insufficiency]

In a patient with hepatic failure of middle grade diltiazem at standard therapeutic dosis for unstable angina caused collateral fuss on atrioventricular conduction. This event is not considered in medical literature or on the schedule of the product. Because of the pharmacokinetics features of diltiazem, a higher risk of side effects can be expected if a abnormality of hepatic function is present.

[ECG monitoring in full-term infants. Analysis of the rhythm and variability of heart rate]

BACKGROUND

Heart Rate (HR) and Heart Rate Variability (HRV) depend on the neural control to the heart. HRV can be measured from 24-hours function. Little information is available on cardiac rhythm and on autonomic nervous control to the heart at birth. The aims of the study weew: 1) to study the cardiac rhythm in healthy newborn babies; 2) to asses the normal values for HRV at birth.

METHODS

We studied 20 full term healthy newborn babies. Newborns underwent 24-hours ECG-Holter monitoring. Analysis was performed by a 750 A Del Mar Avionics Analyzer. We determined: Heart Rate (HR), number of extrasystoles, Standard Deviation of all R-R intervals over 24 hours (SDNN) and mean hourly HRV (HRVM). Results about HRV were matched with those of 50 healthy adults.

RESULTS

1) Average HR in the newborn babies was 108 (range: 55-198); we found high prevalence of supraventricular extrasystoles. 2) We determined reference value for HRV. SDNN was 55 +/- 17 ms in newborns. SDNN of adults was 132 +/- 25 ms (44% higher than in newborns; p < 0.001). HRVM was 46 +/- 14 ms in newborns and 76 +/- 14 ms (p < 0.001).

CONCLUSION

1) Larger intervals of HR in newborn babies compared to literature data and an high prevalence of supraventricular arrhythmias in full term healthy newborn babies. 2) Reference values for HRV in newborn babies. The low values of HRV confirm the immaturity of autonomic cardiac control.

Identification of alpha- and beta-cardiac myosin heavy chain isoforms as major autoantigens in dilated cardiomyopathy

BACKGROUND

Immunization with cardiac myosin induces experimental autoimmune heart disease in genetically predisposed mice. These mice produce heart-specific autoantibodies, some of which are directed against the cardiac myosin isoform.

METHODS AND RESULTS

We have reported the presence of circulating heart-specific autoantibodies in 26% of patients with idiopathic dilated cardiomyopathy (DCM) using indirect immunofluorescence. To identify the autoantigen(s) recognized by heart-specific autoantibodies in human disease, we tested, by Western blotting, sera from 26 DCM patients, 14 of whom were cardiac antibody-positive and 12 antibody-negative, as well as sera from 12 patients with cardiac failure from ischemic or valvular heart disease and from 13 normal subjects who were cardiac antibody-negative. Crude myofibrillar proteins and myosin preparations extracted from human atrial or ventricular specimens were used as antigens. Sodium dodecyl sulfate polyacrylamide gel electrophoresis was performed. The proteins were electrophoretically transferred to nitrocellulose sheets. The paper strips were incubated in sera from patients or controls at 1:100 dilution; the reaction was revealed with a peroxidase-labeled second antibody against human immunoglobulin. Twelve of the 14 DCM sera (86%) containing heart-specific antibodies reacted with both the alpha- (atrial specific) and beta- (ventricular and slow skeletal) myosin heavy chain isoforms; none of the 13 normal sera (p = 0.0001) and one of the 24 heart failure-negative control sera (4%, p = 0.0001) contained antibodies against myosin heavy chain.

CONCLUSIONS

These findings indicate that alpha- and beta-cardiac myosin heavy chain isoforms as in the murine model of autoimmune heart disease are major autoantigens in patients with idiopathic DCM.

[Idiopathic dilated cardiomyopathy: a persistent viral infection or an organ-specific autoimmune disease? The trial of 2 major pathogenetic hypotheses]

Aetiology and pathogenesis of idiopathic dilated cardiomyopathy (DCM) are uncertain. The two major pathogenetic hypotheses are: 1) autoimmunity; 2) persistent viral infection. Indirect evidence for virus association comes from the finding of raised titres of antibody to coxsackievirus in DCM, but infectious virus has never been isolated in myocardium from DCM patients. Bowles et al. using the slot-blotting technique reported that enteroviral RNA was commonly detectable in the myocardium of patients with myocarditis (53%) and with DCM (52%). Other groups using this as well as more refined hybridization techniques have failed to confirm such a high prevalence. Detection of enteroviral genomic RNA in cardiac tissue does not, however, imply active infection or pathogenicity. Thus the mechanisms of chronic myocardial damage in the absence of whole competent infectious virus remain uncertain. The other major pathogenetic hypothesis in DCM involves autoimmune mediated damage to myocytes. Circulating organ specific autoantibodies have been reported in a quarter of a group of patients with idiopathic DCM. This suggests that there may be autoimmune mechanisms operating at least in this subset of patients, but the exact relation of these antibodies to the pathogenesis and prognosis needs to be defined. The abnormal expression of major histocompatibility complex class II antigens on cardiac microvascular endothelium in endomyocardial biopsy tissue from DCM patients, and the reported association with HLA-DR4 phenotype lend further support to the autoimmune hypothesis. The viral and the autoimmune hypothesis in chronic myocarditis and in DCM are not mutually exclusive. In experimentally murine virus-induced myocarditis infectious virus can no longer be recovered from the myocardium after two weeks, although nucleic acid sequences of the viral genome are still detectable. The development of chronic inflammation takes place only in mice with a predisposing genetic background. Chronic myocyte damage is associated with the production of circulating heart-specific autoantibodies and autoreactive lymphocytes. In this animal model chronic myocarditis appears to be a virus-triggered or precipitated autoimmune disease, rather than a persistent viral infection with tissue damage due to active virus synthesis and replication. A similar transition from acute myocarditis into DCM may occur in man.