Proposal of a Machine Learning Approach for Traffic Flow Prediction

Rapid global urbanization has led to a growing urban population, posing challenges in transportation management. Persistent issues such as traffic congestion, environmental pollution, and safety risks persist despite attempts to mitigate them, hindering urban progress. This paper focuses on the critical need for accurate traffic flow forecasting, considered one of the main effective solutions for containing traffic congestion in urban scenarios. The challenge of predicting traffic flow is addressed by proposing a two-level machine learning approach. The first level uses an unsupervised clustering model to extract patterns from sensor-generated data, while the second level employs supervised machine learning models. Although the proposed approach requires the availability of data from traffic sensors to realize the training of the machine learning models, it allows traffic flow prediction in urban areas without sensors. In order to verify the prediction capability of the proposed approach, a real urban scenario is considered.

Digital Twin of a Water Supply System Using the Asset Administration Shell

The concept of digital twins is one of the fundamental pillars of Industry 4.0. Digital twin allows the realization of a virtual model of a real system, enhancing the relevant performance (e.g., in terms of production rate, risk prevention, energy saving, and maintenance operation). Current literature presents many contributions pointing out the advantages that may be achieved by the definition of a digital twin of a water supply system. The Reference Architecture Model for Industry 4.0 introduces the concept of the Asset Administration Shell for the digital representation of components within the Industry 4.0 ecosystem. Several proposals are currently available in the literature considering the Asset Administration Shell for the realization of a digital twin of real systems. To the best of the authors' knowledge, at the moment, the adoption of Asset Administration Shell for the digital representation of a water supply system is not present in the current literature. For this reason, the aim of this paper is to present a methodological approach for developing a digital twin of a water supply system using the Asset Administration Shell metamodel. The paper will describe the approach proposed by the author and the relevant model based on Asset Administration Shell, pointing out that its implementation is freely available on the GitHub platform.

Proposal of Mapping Digital Twins Definition Language to Open Platform Communications Unified Architecture

The concept of Digital Twin is of fundamental importance to meet the main requirements of Industry 4.0. Among the standards currently available to realize Digital Twins there is the Digital Twins Definition Language. Digital Twin requires exchange of data with the real system it models and with other applications that use the digital replica of the system. In the context of Industry 4.0, a reference standard for an interoperable exchange of information between applications, is Open Platform Communications Unified Architecture. The authors believe that interoperability between Digital Twins and Open Platform Communications Unified Architectures communication standard should be enabled. For this reason, the main goal of this paper is to allow a Digital Twin based on the Digital Twins Definition Language to exchange data with any applications compliant to the Open Platform Communications Unified Architecture. A proposal about the mapping from Digital Twins Definition Language to the Open Platform Communications Unified Architecture will be presented. In order to verify the feasibility of the proposal, an implementation has been made by the authors, and its description will be introduced in the paper. Furthermore, the main results of the validation process accomplished on the basis of this implementation will be given.

Bacillus cereus Bacteremia: An Unusual Case Following Food Poisoning

Introduction/Objective

Bacillus cereus is a spore-forming, gram-positive rod, well known for causing food poisoning. In addition, this bacterium often presents as a contaminant of blood cultures. Differentiating true bacteremia from contamination of blood samples is important as it has treatment implications. Early recognition is necessary, as it can cause septic shock if untreated. We present a challenging case of food poisoning with concomitant bacteremia in a young patient with a history of diabetes mellitus (DM), celiac disease, and new-onset chronic kidney disease (CKD).

Methods/Case Report

A 23-year-old adult male with a history of DM, new-onset CKD, and celiac disease presented with nausea, intermittent vomiting, and lower abdominal pain for 2 weeks. On initial evaluation, he had normal blood pressure but tachypnea and tachycardia. Physical examination was significant for left lower quadrant and flank tenderness. The symptoms were persistent and progressed to point that he could not tolerate meals due to vomiting. Two weeks earlier, he presented with similar complaints along with dysuria and was treated for suspected urinary tract infection with Co-trimoxazole. This time, further workup revealed normal white blood cell count (11.8 k/µL) with 81% neutrophils, elevated creatinine (3.56 mg/dL), blood urea nitrogen (49 mg/dL), and procalcitonin (0.39 ng/mL), with abnormal urinalysis showing increased turbidity, pyuria, and nitrituria. He was started on ceftriaxone, fluids, antiemetics and was admitted to the hospital for further management. The urine culture had no bacterial growth. Two sets of peripheral blood cultures (different sites at different times) had gram-positive rods which eventually turned out to be B. cereus, identified by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS). Levofloxacin was started, and he reported improvement in nausea and vomiting by the next day of admission and was discharged.

Results (if a Case Study enter NA)

NA

Conclusion

Differentiating true B. cereus bacteremia from blood sample contamination is important. Additionally, no symptoms are specific for B. cereus-associated food poisoning, and the presence of risk factors doesn’t always favor this entity over other entities, hence adding difficulty to the diagnosis. A high index of suspicion is needed, as early intervention can prevent the development of life-threatening complications.

Late toxicities burden in patients with radioiodine-refractory differentiated thyroid cancer treated with lenvatinib

PURPOSE

Radioactive-iodine (RAI)-resistant differentiated thyroid cancer (DTC) patients benefit from multi-kinase inhibitors (MKIs), such as lenvatinib. Incidence of treatment-related (TR) late toxicities has been not yet described.

METHODS

From January 2015 to June 2019 we retrospectively reviewed clinical records of patients with RAI-resistant DTC treated with lenvatinib at Istituto Nazionale dei Tumori (Milan, Italy). New side effect of any grade, appeared after 12 months of lenvatinib, was defined as late adverse event (AE). Descriptive analyses were performed. Survival curves were estimated with Kaplan-Meier method and compared with log-rank test.

RESULTS

Thirty-seven patients were included, 65% had ≥65 years and 68% were female. Thirty patients received lenvatinib for >12 months. Lenvatinib was started at ≤20 mg/daily in 59% of patients, 64% were ≥65 years. The frequency of late AEs was 80% and cardiovascular toxicity was the most common (57%). There was no difference in the incidence of late AEs between younger/older population (77% and 82%, respectively). Median lenvatinib treatment duration (TD) was 39.96 months (95% CI 21.64-NR): 39.96 months for patients <65 years (95% CI: 13.25-NR) and 37.53 months for those ≥65 years, respectively (95% CI: 15.85-NR). Median overall survival (OS) was 39.96 months (95% CI: 21.84-NR), no statistically differences in OS was observed between younger (<65 years) and older patients (≥65 years) (HR 1.013; 95% CI 0.963-1.065; p = 0.62).

CONCLUSION

Late toxicity burden of lenvatinib is not negligible. Cardiovascular toxicity remains the principal side effect even after a prolonged lenvatinib exposition.

Semantic Interoperability between IEC 61850 and oneM2M for IoT-Enabled Smart Grids

In the era of Industry 4.0, pervasive adoption of communication technologies based on the Internet of Things represents a very strong requirement in several domains. In the smart grid domain, there is the need to overcome one of the main limitations of the current electric grid, allowing the use of heterogeneous devices capable of measuring, monitoring and exchanging information about grid components. For this reason, current literature often presents research activities about enabling internet of things (IoT) in smart grids; in particular, several proposals aim to realize interworking between IoT and smart grid communication standards, allowing exchange of information between IoT devices and the electrical grid components. Semantic interoperability should be achieved in an interworking solution in order to provide a common meaning of the data exchanged by heterogeneous devices, even if they belong to different domains. Until now, semantic interoperability remains an open challenge in the smart grid field. The paper aims to propose a novel solution of interworking between two of the most used communication systems in smart grids and IoT domains, i.e., IEC 61850 and oneM2M, respectively. A semantic interoperability solution is also proposed to be used in the interworking scheme here presented.

Workplace violence, early neurological symptoms, and metabolic or psychiatric disorders

Workplace violence is ubiquitous. Neuropsychological symptoms, such as headaches and sleep problems, may be the earliest consequences of violent acts, and in turn are associated with an increased risk of cardiovascular and psychiatric disorders. Systematic research on this topic can help treatment and prevention.

905 health & social workers (male 331, 36.6%; mean age 46 + 11.4 years), during their periodical medical examination in the workplace, were asked to fill in a standardized questionnaire containing the Violent Incident Form on the episodes of violence suffered, the Headache Impact Test on headache and the PSQI on sleep problems. Anxiety and depression were evaluated with the Goldberg scale.

Workers reported having suffered physical assaults (5.2%), threats (11.5%), and harassment (10.2%) in the previous year. Workers who experienced violence had an increased risk of headaches (OR 2.80, CI95% 1.55-5.05 for physical violence, OR 1.83 CI95% 1.21-2.78 for threats, OR 2.46 CI95% 1.59-3.96 for harassment) and of sleep problems (OR 2.46, CI95% 1.33-4.57 for physical violence, OR 2.81 CI95% 1.82-4.33 for threats, OR 5.09 CI95% 3.04-8.51 for harassment).

Headache and sleep problems were significantly correlated with the components of the metabolic syndrome (hypertension, dyslipidemia, hyperglycaemia, obesity): Pearson's r was 0.069 for headache (p &lt; 0.05), 0.142 for sleep quality (p &lt; 0.001). Head and sleep problems were also correlated with anxiety (r = 0.519 and 0.670, respectively) and with depression (r = 0.457 and 0.619).

Violence at work was associated with an increased risk of headaches and sleep problems. These symptoms were associated with the components of the metabolic syndrome, with anxiety and with depression.

Early detection of symptoms such as headaches and sleep problems allows individual treatment measures to be put in place. The identification of the causes of these morbid phenomena allows to implement primary prevention measures in the workplace.

Key messages

Workplace violence causes headache and sleep problems, which, in turn, are associated with metabolic and psychiatric disorders. Periodic surveillance of workers is useful for improving public health.

Flu vaccination coverage in a large Italian teaching hospital: the example of the leaders

Key messages

Annual flu vaccination among healthcare workers (HCWs) is recommended to prevent influenza and to avoid its transmission especially to frail patients. This study shows the growing flu vaccination coverage rate in our teaching hospital and the effectiveness of the example given by the vaccinated leaders in increasing the coverage among all HCWs.

Adjuvant androgen deprivation therapy for poor-risk, androgen receptor-positive salivary duct carcinoma

AIM

Salivary duct carcinoma (SDC), an aggressive subtype of salivary gland cancer, is androgen receptor (AR)-positive in 67-96% of cases. In patients with locally recurrent and metastatic (R/M) AR-positive SDC, androgen deprivation therapy (ADT) has an overall response rate of 18-64.7%. In this study, we describe the efficacy of adjuvant ADT in patients with poor-risk (stage 4a) AR-positive SDC.

METHODS

This is a retrospective cohort study in which patients with stage 4a AR-positive SDC were offered adjuvant ADT, i.e. bicalutamide, luteinizing hormone-releasing hormone (LHRH) analogue or a combination of these after tumour resection. In the control group, data were collected on patients with stage 4a SDC who underwent a tumour resection but did not receive adjuvant ADT.

RESULTS

Twenty-two AR-positive SDC patients were treated with adjuvant ADT for a median duration of 12 months. The control group consisted of 111 SDC patients. After a median follow-up of 20 months in the ADT-treated patients and 26 months in the control group, the 3-year disease-free survival (DFS) was estimated as 48.2% (95% confidence interval [CI] 14.0-82.4%) and 27.7% (95% CI 18.5-36.9%) (P = 0.037). Multivariable Cox regression analysis showed a hazard ratio of 0.138 (95% CI 0.025-0.751, P = 0.022) for DFS and 0.064 (95% CI 0.005-0.764, P = 0.030) for overall survival (OS) in favour of the ADT-treated patients.

CONCLUSION

Poor-risk, AR-positive SDC patients who received adjuvant ADT have a significantly longer DFS compared with patients in the control group, who did not receive adjuvant ADT. For OS, this was just below and above the significance level, in case there was or was no correction for confounders.

Prevalence and phenotype of the c.1529C>T SPG7 variant in adult-onset cerebellar ataxia in Italy

BACKGROUND AND PURPOSE

Hereditary ataxias are heterogeneous groups of neurodegenerative disorders, characterized by cerebellar syndromes associated with dysarthria, oculomotor and corticospinal signs, neuropathy and cognitive impairment. Recent reports have suggested mutations in the SPG7 gene, causing the most common form of autosomal recessive spastic paraplegia (MIM#607259), as a main cause of ataxias. The majority of described patients were homozygotes or compound heterozygotes for the c.1529C>T (p.Ala510Val) change. We screened a cohort of 895 Italian patients with ataxia for p.Ala510Val in order to define the prevalence and genotype-phenotype correlation of this variant.

METHODS

We set up a rapid assay for c.1529C>T using restriction enzyme analysis after polymerase chain reaction amplification. We confirmed the diagnosis with Sanger sequencing.

RESULTS

We identified eight homozygotes and 13 compound heterozygotes, including two novel variants affecting splicing. Mutated patients showed a pure cerebellar ataxia at onset, evolving in mild spastic ataxia (alternatively) associated with dysarthria (~80% of patients), urinary urgency (~30%) and pyramidal signs (~70%). Comparing homozygotes and compound heterozygotes, we noted a difference in age at onset and Scale for the Assessment and Rating of Ataxia score between the two groups, supporting an earlier and more severe phenotype in compound heterozygotes versus homozygotes.

CONCLUSIONS

The SPG7 c.1529C>T (p.Ala510Val) mutants accounted for 2.3% of cerebellar ataxia cases in Italy, suggesting that this variant should be considered as a priority test in the presence of late-onset pure ataxia. Moreover, the heterozygous/homozygous genotype appeared to predict the onset of clinical manifestation and disease progression.

Efficacy and safety of single-agent pan-human epidermal growth factor receptor (HER) inhibitor dacomitinib in locally advanced unresectable or metastatic skin squamous cell cancer

BACKGROUND

In recurrent or metastatic (R/M) skin squamous cell cancer (sSCC) not amenable to radiotherapy (RT) or surgery, chemotherapy (CT) has a palliative intent and limited clinical responses. The role of oral pan-HER inhibitor dacomitinib in this setting was investigated within a clinical trial.

METHODS

Patients with diagnosis of R/M sSCC were treated. Dacomitinib was started at a dose of 30 mg daily (QD) for 15 d, followed by 45 mg QD. Primary end-point was response rate (RR). Tumour samples were analysed through next-generation sequencing using a custom panel targeting 36 genes associated with sSCC.

RESULTS

Forty-two patients (33 men; median age 77 years) were treated. Most (86%) received previous treatments consisting in surgery (86%), RT (50%) and CT (14%). RR was 28% (2% complete response; 26% partial response), disease control rate was 86%. Median progression-free survival and overall survival were 6 and 11 months, respectively. Most patients (93%) experienced at least one adverse event (AE): diarrhoea, skin rash (71% each), fatigue (36%) and mucositis (31%); AEs grade 3-4 occurred in 36% of pts. In 16% of cases, treatment was discontinued because of drug-related toxicity. TP53, NOTCH1/2, KMT2C/D, FAT1 and HER4 were the most frequently mutated genes. BRAF, NRAS and HRAS mutations were more frequent in non-responders, and KMT2C and CASP8 mutations were restricted to this subgroup.

CONCLUSIONS

In sSCC, dacomitinib showed activity similar to what was observed with anti-epidermal growth factor receptor agents, and durable clinical benefit was observed. Safety profile was comparable to previous experiences in other cancers. Molecular pt selection could improve therapeutic ratio.

The steroid response to human chorionic gonadotropin (hCG) stimulation in men with Klinefelter syndrome does not change using immunoassay or mass spectrometry

PURPOSE

Liquid-chromatography tandem mass-spectrometry (LC-MS/MS) was developed in parallel to Immunoassays (IAs) and today is proposed as the "gold standard" for steroid assays. Leydig cells of men with Klinefelter syndrome (KS) are able to respond to human chorionic gonadotropin (hCG) stimulation, even if testosterone (T) production was impaired. The aim was to evaluate how results obtained by IAs and LC-MS/MS can differently impact on the outcome of a clinical research on gonadal steroidogenesis after hCG stimulation.

METHODS

A longitudinal, prospective, case-control clinical trial. (clinicaltrial.gov NCT02788136) was carried out, enrolling KS men and healthy age-matched controls, stimulated by hCG administration. Serum steroids were evaluated at baseline and for 5 days after intramuscular injection of 5000 IU hCG using both IAs and LC-MS/MS.

RESULTS

13 KS patients (36 ± 9 years) not receiving T replacement therapy and 14 controls (32 ± 8 years) were enrolled. T, progesterone, cortisol, 17-hydroxy-progesterone (17OHP) and androstenedione, were significantly higher using IAs than LC-MS/MS. IAs and LC-MS/MS showed direct correlation for all five steroids, although the constant overestimation detected by IAs. Either methodology found the same 17OHP and T increasing profile after hCG stimulation, with equal areas under the curves (AUCs).

CONCLUSIONS

Although a linearity between IA and LC-MS/MS is demonstrated, LC-MS/MS is more sensitive and accurate, whereas IA shows a constant overestimation of sex steroid levels. This result suggests the need of reference intervals built on the specific assay. This fundamental difference between these two methodologies opens a deep reconsideration of what is needed to improve the accuracy of steroid hormone assays.

Copy number variants analysis in a cohort of isolated and syndromic developmental delay/intellectual disability reveals novel genomic disorders, position effects and candidate disease genes

BACKGROUND

Array-comparative genomic hybridization (array-CGH) is a widely used technique to detect copy number variants (CNVs) associated with developmental delay/intellectual disability (DD/ID).

AIMS

Identification of genomic disorders in DD/ID.

MATERIALS AND METHODS

We performed a comprehensive array-CGH investigation of 1,015 consecutive cases with DD/ID and combined literature mining, genetic evidence, evolutionary constraint scores, and functional information in order to assess the pathogenicity of the CNVs.

RESULTS

We identified non-benign CNVs in 29% of patients. Amongst the pathogenic variants (11%), detected with a yield consistent with the literature, we found rare genomic disorders and CNVs spanning known disease genes. We further identified and discussed 51 cases with likely pathogenic CNVs spanning novel candidate genes, including genes encoding synaptic components and/or proteins involved in corticogenesis. Additionally, we identified two deletions spanning potential Topological Associated Domain (TAD) boundaries probably affecting the regulatory landscape.

DISCUSSION AND CONCLUSION

We show how phenotypic and genetic analyses of array-CGH data allow unraveling complex cases, identifying rare disease genes, and revealing unexpected position effects.

Management of tyrosine kinase inhibitors (TKI) side effects in differentiated and medullary thyroid cancer patients

Four tyrosine kinase inhibitors (TKIs) have been recently licensed in thyroid cancer (TC), sorafenib and lenvatinib for differentiated TC, vandetanib and cabozantinib for medullary TC. Others TKIs such as axitinib, pazopanib, sunitinib, have been tested within phase II trials. The toxicity burden associated to TKIs is not negligible. Drug reductions and interruptions are common, definitive drug withdrawals have also been reported as well as toxic deaths in more rare cases. In this context, the prevention of toxicities is mandatory to allow patients to stay on treatment as long as possible without dose and schedule modifications. Both physicians and patients should be educated to recognize drug-related toxicities in order to manage them in an early phase. Tools (e.g. toxicities summary booklet) for physicians and patients could be considered to improve the knowledge on side effects management. Guidelines, whenever available, should be followed.

Ultimate Limit in the Spectral Resolution of Extreme Ultraviolet Frequency Combs

We present the results of direct interferometric measurements on the pulse-to-pulse phase jitter of a metrological, fiber-based, infrared (IR) frequency comb. We show that the short-time evolution of such phase fluctuations, which cannot be actively controlled by any feedback system, imposes a stringent limit on the tooth linewidth of extreme ultraviolet (XUV) combs produced by high-order harmonic conversion, thus explaining the difference of 9 orders of magnitude between the coherence times of state-of-the-art IR and XUV frequency combs.

A methodological approach for using high-level Petri Nets to model the immune system response

BACKGROUND

Mathematical and computational models showed to be a very important support tool for the comprehension of the immune system response against pathogens. Models and simulations allowed to study the immune system behavior, to test biological hypotheses about diseases and infection dynamics, and to improve and optimize novel and existing drugs and vaccines. Continuous models, mainly based on differential equations, usually allow to qualitatively study the system but lack in description; conversely discrete models, such as agent based models and cellular automata, permit to describe in detail entities properties at the cost of losing most qualitative analyses. Petri Nets (PN) are a graphical modeling tool developed to model concurrency and synchronization in distributed systems. Their use has become increasingly marked also thanks to the introduction in the years of many features and extensions which lead to the born of "high level" PN.

RESULTS

We propose a novel methodological approach that is based on high level PN, and in particular on Colored Petri Nets (CPN), that can be used to model the immune system response at the cellular scale. To demonstrate the potentiality of the approach we provide a simple model of the humoral immune system response that is able of reproducing some of the most complex well-known features of the adaptive response like memory and specificity features.

CONCLUSIONS

The methodology we present has advantages of both the two classical approaches based on continuous and discrete models, since it allows to gain good level of granularity in the description of cells behavior without losing the possibility of having a qualitative analysis. Furthermore, the presented methodology based on CPN allows the adoption of the same graphical modeling technique well known to life scientists that use PN for the modeling of signaling pathways. Finally, such an approach may open the floodgates to the realization of multi scale models that integrate both signaling pathways (intra cellular) models and cellular (population) models built upon the same technique and software.

Expression of the High-Affinity Laminin Receptor (67 kDa) in Normal Human Skin and Appendages

The interaction of cells with extracellular matrix components plays a significant role in the regulation of cell biology. Laminin is a large glycoprotein involved in fundamental interactions between cells and the basement membrane. Several cell surface receptors are responsible for cell-matrix interactions. The 67 kDa high affinity laminin receptor, 67LR, is involved in the adhesion of normal cells to the laminin network and is also associated with the metastatic phenotype of some tumoral cells. We have investigated the expression of laminin and of the 67LR in normal human skin using immunoperoxidase staining. Twenty samples of skin were analyzed. Antibody against laminin reacted in a continuous linear band at the dermal-epidermal junction, as well as basement membranes of hair follicles, sebaceous and eccrine sweat glands, and dermal blood vessels. The epidermis and the follicular epithelium were negative for laminin. The 67LR seemed not to be expressed on the basal surface of basal keratinocytes. The major expression of this receptor may be detected in the upper half of the spinous layer and in the granular layer. The cells of the outer root sheath in hair follicle showed the same immunohistochemical pattern described for epidermis. In sebaceous glands and in eccrine sweat glands the secreting epithelium was positive. Endothelial cells of dermal blood vessels were routinely positive for 67LR. We observed that the expression of the 67LR in normal human skin is mostly located in epidermal areas in which the keratinizing process was particularly advanced.

Computational Modeling of PI3K/AKT and MAPK Signaling Pathways in Melanoma Cancer

BACKGROUND

Malignant melanoma is an aggressive tumor of the skin and seems to be resistant to current therapeutic approaches. Melanocytic transformation is thought to occur by sequential accumulation of genetic and molecular alterations able to activate the Ras/Raf/MEK/ERK (MAPK) and/or the PI3K/AKT (AKT) signalling pathways. Specifically, mutations of B-RAF activate MAPK pathway resulting in cell cycle progression and apoptosis prevention. According to these findings, MAPK and AKT pathways may represent promising therapeutic targets for an otherwise devastating disease.

RESULT

Here we show a computational model able to simulate the main biochemical and metabolic interactions in the PI3K/AKT and MAPK pathways potentially involved in melanoma development. Overall, this computational approach may accelerate the drug discovery process and encourages the identification of novel pathway activators with consequent development of novel antioncogenic compounds to overcome tumor cell resistance to conventional therapeutic agents. The source code of the various versions of the model are available as S1 Archive.

An ultrastable Michelson interferometer for high-resolution spectroscopy in the XUV

We developed an ultra-stable and accurately-controllable Michelson interferometer to be used in a deeply unbalanced arm configuration for split-pulse XUV Ramsey-type spectroscopy with high-order laser harmonics. The implemented active and passive stabilization systems allow one to reach instabilities in the nanometer range over meters of relative optical path differences. Producing precisely delayed pairs of pump pulses will generate XUV harmonic pulses that may significantly improve the achievable spectral resolution and the precision of absolute frequency measurements in the XUV.

Intraprocedural cortisol measurement increases adrenal vein sampling success rate in primary aldosteronism

BACKGROUND

Adrenal venous sampling (AVS) is the gold standard for the identification of unilateral primary aldosteronism (PA), but is technically difficult. The aim of our study was to assess whether intraprocedural cortisol measurement (IPCM) increases AVS success rate.

METHODS

Twenty-five consecutive PA patients underwent cosyntropin-stimulated AVS. Cortisol was measured immediately in a first set of samples drawn from adrenal veins and inferior vena cava. The selectivity criterion was an adrenal vein-to-inferior vena cava cortisol ratio ≥5. If bilateral selectivity was not achieved in a first set of samples, a second set was obtained during the same radiological session. PA was judged as unilateral if the gradient of cortisol-corrected aldosterone between dominant and nondominant side was >3.5. Twenty-five consecutive PA patients who had previously been submitted to AVS without IPCM served as historical controls. Lateralizing patients who underwent unilateral adrenalectomy were followed for 2 years after surgery.

RESULTS

Bilateral selectivity using IPCM was achieved in 19/25 patients in the first set of samples, and in an additional four cases in the second set (92% vs. 76%; P = 0.06). The final rate of bilateral selectivity was higher than that obtained in the historical series (23/25 vs. 16/25, P = 0.04), whereas bilateral selectivity in the first set of samples was not different from that achieved in the historical series. Nineteen lateralizing patients (13 of the present series, six of the historical series) were submitted to adrenalectomy, resulting in reversal of PA.

CONCLUSIONS

IPCM increases the success rate of AVS.