Assessing cancer risk in the anterior part of the prostate using micro-ultrasound: validation of a novel distinct protocol.

PURPOSE: To develop and validate a micro-ultrasound risk score that predicts the likelihood of significant prostate cancer in the anterior zone. METHODS: Patients were enrolled from three expert institutions familiar with micro-ultrasound. The study was conducted in two phases. First, the PRI-MUS anterior score was developed by assessing selected prostate videos from patients who subsequently underwent radical prostatectomy. Second, seven urology readers with varying levels of experience in micro-ultrasound examination evaluated prostate loops according to the PRI-MUS anterior score. Each reader watched the videos and recorded the likelihood of the presence of significant cancer in the anterior part of the prostate in a three-point scale. The coherence among the readers was calculated using the Fleiss kappa and the Cronbach alpha. RESULTS: A total of 102 selected prostate scans were used to develop the risk assessment for anterior zone cancer in the prostate. The score comprised three categories: likely, equivocal, and unlikely. The median (IQR) sensitivity, specificity, positive predictive value, and negative predictive value for the seven readers were 72% (68-84), 68% (64-84), 75% (72-81), and 73% (71-80), respectively. The mean SD ROC AUC was 0.75 ± 2%, while the Fleiss kappa and the Cronbach alpha were 0.179 and 0.56, respectively. CONCLUSION: Micro-ultrasound can detect cancerous lesions in the anterior part of the prostate. When combined with the PRI-MUS protocol to assess the peripheral part, it enables an assessment of the entire prostate gland. Pending external validation, the PRI-MUS anterior score developed in this study might be implemented in clinical practice.

Prenatal magnetic resonance imaging of complex female genitourinary system abnormalities, what the fetal medicine specialist needs to know.

Complex female genitourinary system anomalies include a wide spectrum of uncommon pathologies, caused from the abnormal separation of the urorectal septum and the urogenital sinus in early embryonic life. The resulting fusion of the distal urinary, genital and intestinal tracts increases the risk of death in utero and alters the normal organ functionality and the quality of life in survivors. An accurate prenatal identification of these pathologies depends mainly on prior suspicion at ultrasound screening, but also requires a solid knowledge of embryology and familiarity with the different patterns of malformation. Prenatal MRI provides an excellent anatomic evaluation of the fetal anatomy that may improve the diagnosis in complex cases with inconclusive echographic findings. The additional information can help both families and medical teams to better evaluate the severity of the pathology and the postnatal prognosis and therefore to better orientate the management during pregnancy, at delivery and after birth. This review article describes the embryological basis and the clinical findings of the most relevant pathologies included in the spectrum. It also describes the imaging signs on prenatal MRI studies in a series of confirmed cases and proposes a diagnostic algorithm based on imaging findings for guiding prenatal diagnosis.

COVID-19 risk stratification algorithms based on sTREM-1 and IL-6 in emergency department.

BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic has led to surges of patients presenting to emergency departments (EDs) and potentially overwhelming health systems. OBJECTIVE: We sought to assess the predictive accuracy of host biomarkers at clinical presentation to the ED for adverse outcome. METHODS: Prospective observational study of PCR-confirmed COVID-19 patients in the ED of a Swiss hospital. Concentrations of inflammatory and endothelial dysfunction biomarkers were determined at clinical presentation. We evaluated the accuracy of clinical signs and these biomarkers in predicting 30-day intubation/mortality, and oxygen requirement by calculating the area under the receiver-operating characteristic curve and by classification and regression tree analysis. RESULTS: Of 76 included patients with COVID-19, 24 were outpatients or hospitalized without oxygen requirement, 35 hospitalized with oxygen requirement, and 17 intubated/died. We found that soluble triggering receptor expressed on myeloid cells had the best prognostic accuracy for 30-day intubation/mortality (area under the receiver-operating characteristic curve, 0.86; 95% CI, 0.77-0.95) and IL-6 measured at presentation to the ED had the best accuracy for 30-day oxygen requirement (area under the receiver-operating characteristic curve, 0.84; 95% CI, 0.74-0.94). An algorithm based on respiratory rate and sTREM-1 predicted 30-day intubation/mortality with 94% sensitivity and 0.1 negative likelihood ratio. An IL-6-based algorithm had 98% sensitivity and 0.04 negative likelihood ratio for 30-day oxygen requirement. CONCLUSIONS: sTREM-1 and IL-6 concentrations in COVID-19 in the ED have good predictive accuracy for intubation/mortality and oxygen requirement. sTREM-1- and IL-6-based algorithms are highly sensitive to identify patients with adverse outcome and could serve as early triage tools.

Lung Ultrasonography for Risk Stratification in Patients with Coronavirus Disease 2019 (COVID-19): A Prospective Observational Cohort Study.

BACKGROUND: Lung ultrasonography (LUS) is a promising pragmatic risk-stratification tool in coronavirus disease 2019 (COVID-19). This study describes and compares LUS characteristics between patients with different clinical outcomes. METHODS: Prospective observational study of polymerase chain reaction-confirmed adults with COVID-19 with symptoms of lower respiratory tract infection in the emergency department (ED) of Lausanne University Hospital. A trained physician recorded LUS images using a standardized protocol. Two experts reviewed images blinded to patient outcome. We describe and compare early LUS findings (≤24 hours of ED presentation) between patient groups based on their 7-day outcome (1) outpatients, (2) hospitalized, and (3) intubated/dead. Normalized LUS score was used to discriminate between groups. RESULTS: Between 6 March and 3 April 2020, we included 80 patients (17 outpatients, 42 hospitalized, and 21 intubated/dead). Seventy-three patients (91%) had abnormal LUS (70% outpatients, 95% hospitalized, and 100% intubated/dead; P = .003). The proportion of involved zones was lower in outpatients compared with other groups (median [IQR], 30% [0-40%], 44% [31-70%], 70% [50-88%]; P < .001). Predominant abnormal patterns were bilateral and there was multifocal spread thickening of the pleura with pleural line irregularities (70%), confluent B lines (60%), and pathologic B lines (50%). Posterior inferior zones were more often affected. Median normalized LUS score had a good level of discrimination between outpatients and others with area under the ROC of .80 (95% CI, .68-.92). CONCLUSIONS: Systematic LUS has potential as a reliable, cheap, and easy-to-use triage tool for the early risk stratification in patients with COVID-19 presenting to EDs.

[Breast cancer during pregnancy]. / Cancer du sein chez la femme en.

The management of patients with breast cancer during their pregnancy is challenging. A good coordination is required between the oncology and obstetrics teams in order to ensure appropriate care, while providing a reassuring environment during this stressful period. Most often, the pregnancy can continue without delaying the initiation of oncological treatments, offering a prognosis similar to non-pregnant women. Surgery and chemotherapy can be done during pregnancy, unlike endocrine therapy, radiotherapy and antibody treatments which can only be given postpartum. While some imaging techniques are compatible, others require special measures or are contraindicated. We discuss these points in the context of a clinical situation.

La prise en charge des patientes présentant un cancer du sein durant leur grossesse est un challenge. Elle exige une bonne coordination entre les équipes oncologique et obstétricale afin d'assurer des soins appropriés tout en offrant un cadre rassurant en cette période de grand stress. Le plus souvent, la grossesse peut être poursuivie sans retarder l'initiation des traitements oncologiques, avec un pronostic similaire aux femmes non enceintes. La chirurgie et la chimiothérapie peuvent être entreprises en cours de grossesse, contrairement à l'hormonothérapie, la radiothérapie et les traitements par anticorps qui ne peuvent être administrés qu'en post-partum. Si certaines techniques d'imagerie sont compatibles, d'autres requièrent des mesures particulières ou sont contre-indiquées. Nous discutons de ces points dans le cadre d'une situation clinique.

[Cancer center clinical nurse: The experience of the CHUV Prostate Cancer Center]. / Infirmière clinicienne de centre du cancer : l'expérience du Centre de la prostate du CHUV.

The University Hospital of Lausanne has heavily invested in the development of interdisciplinary oncology centers to improve the quality of care, and structure research and training. By integrating specialist nurses, it follows international recommendations. These specialists' nurses rephrase the information given by the doctor and ensure patients' understanding. They assess the patient's psychosocial situation and provides guidance if necessary. They support the patient in making informed choices about treatment and coping strategies. In addition to the outpatient clinics planned in accordance with the care pathway, she can be contacted between appointments to answer questions or concerns of any kind. This article shows the added value of these nurses in the care of oncology patients.

Le CHUV s'est fortement investi dans le développement de centres interdisciplinaires en oncologie afin d'améliorer la qualité de la prise en charge, de structurer la recherche et la formation. En y intégrant des infirmières cliniciennes, il suit les recommandations internationales. Ces infirmières reprennent les informations données par le médecin et s'assurent de la compréhension du patient. Elles évaluent sa situation psychosociale et l'orientent au besoin. Elles soutiennent le patient dans ses choix de traitement ainsi que dans ses stratégies d'adaptation. Outre les entretiens planifiés en fonction du parcours de soins, elles sont joignables entre les rendez-vous pour répondre à des questions ou préoccupations de tout ordre. Cet article montre la plus-value que la présence de ces infirmières offre à la prise en charge des patients oncologiques.

Procalcitonin and lung ultrasonography point-of-care testing to decide on antibiotic prescription in patients with lower respiratory tract infection in primary care: protocol of a pragmatic cluster randomized trial.

BACKGROUND: A minority of patients presenting with lower respiratory tract infection (LRTI) to their general practitioner (GP) have community-acquired pneumonia (CAP) and require antibiotic therapy. Identifying them is challenging, because of overlapping symptomatology and low diagnostic performance of chest X-ray. Procalcitonin (PCT) can be safely used to decide on antibiotic prescription in patients with LRTI. Lung ultrasound (LUS) is effective in detecting lung consolidation in pneumonia and might compensate for the lack of specificity of PCT. We hypothesize that combining PCT and LUS, available as point-of care tests (POCT), might reduce antibiotic prescription in LRTIs without impacting patient safety in the primary care setting. METHODS: This is a three-arm pragmatic cluster randomized controlled clinical trial. GPs are randomized either to PCT and LUS-guided antibiotic therapy or to PCT only-guided therapy or to usual care. Consecutive adult patients with an acute cough due to a respiratory infection will be screened and included if they present a clinical pneumonia as defined by European guidelines. Exclusion criteria are previous antibiotics for the current episode, working diagnosis of sinusitis, severe underlying lung disease, severe immunosuppression, hospital admission, pregnancy, inability to provide informed consent and unavailability of the GP. Patients will fill in a 28 day-symptom diary and will be contacted by phone on days 7 and 28. The primary outcome is the proportion of patients prescribed any antibiotic up to day 28. Secondary outcomes include clinical failure by day 7 (death, admission to hospital, absence of amelioration or worsening of relevant symptoms) and by day 28, duration of restricted daily activities, episode duration as defined by symptom score, number of medical visits, number of days with side effects due to antibiotics and a composite outcome combining death, admission to hospital and complications due to LRTI by day 28. An evaluation of the cost-effectiveness and of processes in the clinic using a mixed qualitative and quantitative approach will also be conducted. DISCUSSION: Our intervention targets only patients with clinically suspected CAP who have a higher pretest probability of definite pneumonia. The intervention will not substitute clinical assessment but completes it by introducing new easy-to-perform tests. TRIAL REGISTRATION: The study was registered on the 19th of June 2017 on the clinicaltrials.gov registry using reference number; NCT03191071 .

[The breech comeback : implementation of a vaginal delivery protocol in the CHUV]. / Le retour du siège : mise en place d'un protocole d'accouchement par voie basse au CHUV.

Choosing between vaginal delivery and caesarean section in cases of breech presentation is still a matter of controversy. In this article, we present the Lausanne University Hospital's protocol following the introduction of an institutional vaginal breech delivery policy. Vaginal breech delivery is a viable alternative to caesarean section in the presence of an experienced obstetrician and rigorous patient-selection criteria.

Le choix entre un accouchement par voie basse et une césarienne reste controversé lors de présentation en siège. Nous présentons dans cet article le protocole de la Maternité du Centre hospitalier universitaire vaudois suite à l'introduction d'une politique favorisant les accouchements en siège. L'accouchement par voie basse du siège est désormais une alternative possible à la césarienne en présence d'obstétriciens expérimentés et de critères de sélection rigoureux des patientes.

Ultrasonography : an useful diagnostic tool for the general practitioner. / Echographie : un outil utile pour la démarche diagnostique en médecine de famille.

The ultrasound has become an increasingly popular tool in the clinical assessment of patients, not least in the field of general medicine. The technical evolution as well as the recent changes of the application of ultrasounds allows for rapid and targeted exams that has the potential to improve the care of patients. With the help of recent articles regarding ultrasound (US) in general medical practice, this article presents several useful indications for the primary care physician as well as shows today's training in Switzerland and demonstrates the need of an adapted training to better respond to today's need.

L'échographie est devenue un outil de plus en plus populaire pour l'évaluation et l'examen clinique des patients, notamment dans le domaine de la médecine de famille. L'évolution de la technique et les modes d'utilisation permettent des examens ciblés et rapides qui promettent d'améliorer la qualité des soins aux patients. Basé sur des études récentes traitant du sujet de l'ultrasonographie (US) en médecine générale, cet article présente les indications d'utilisation de l'échographie par le médecin de premier recours, il démontre le niveau de formation actuelle en Suisse et aborde la nécessité d'une formation adaptée pour mieux répondre aux besoins d'aujourd'hui.

[Management of genitourinary trauma]. / Prise en charge des traumatismes urogénitaux.

Urogenital trauma often occurs in the context of polytrauma patients. In this article, aimed at primary care practitioners and emergency physicians, we summarise the epidemiology and aetiology of these traumas as well as their management. The goal is to allow primary healthcare professionals to become acquainted with diagnostic and therapeutic strategies in genitourinary trauma patients.

Les traumatismes des organes génitaux externes et du système urinaire chez l'adulte se rencontrent souvent dans le contexte de patients polytraumatisés. Dans cet article, qui s'adresse aux médecins de premiers recours ainsi qu'aux membres des services d'urgences, nous résumons les caractéristiques épidémiologiques et étiologiques de ces lésions ainsi que les dernières recommandations concernant leur prise en charge. Le but est de permettre aux différents intervenants de se familiariser avec les stratégies diagnostiques et thérapeutiques face à un patient présentant un traumatisme urogénital.

[Prostate biopsy: which strategy for which patient?]. / Biopsies de la prostate en 2015: quelle biopsie pour quel patient?

The adoption of multiparametric MRI within the diagnostic pathway has allowed urologists to move from random biopsy to targeted biopsy directed towards MR-visible lesions. The use of software for MR to TRUS fusion may enhance the diagnostic accuracy of targeted biopsy. To determine the eligibility for tissue-preserving approaches, further precision is required, and template prostate mapping biopsy may be offered. The employment of novel biopsy techniques provide better characterisation of the disease, and allows a tailored approach to a single subject.

[Focal therapy in prostate cancer: rationale, results and perspectives]. / Thérapie focale du cancer de la prostate: rationnel, résultats et perspectives.

Focal therapy is a novel treatment strategy in prostate cancer aiming to treat only the area of the gland harbouring clinically significant disease. The overall objective is to maintain the oncological benefit of active treatment while minimising treatment-related morbidity. Leading centres are currently evaluating various minimally invasive technologies in a rigorous manner. Oncological and functional results in mid-term are encouraging with low rate of urinary incontinence and erectile dysfunction. However, the oncological outcome needs to be evaluated in the long-term in the light of the prolonged natural history of the disease.

Accuracy and Reliability of Pelvimetry Measures Obtained by Manual or Automatic Labeling of Three-Dimensional Pelvic Models.

(1) Background: The morphology of the pelvic cavity is important for decision-making in obstetrics. This study aimed to estimate the accuracy and reliability of pelvimetry measures obtained when radiologists manually label anatomical landmarks on three-dimensional (3D) pelvic models. A second objective was to design an automatic labeling method. (2) Methods: Three operators segmented 10 computed tomography scans each. Three radiologists then labeled 12 anatomical landmarks on the pelvic models, which allowed for the calculation of 15 pelvimetry measures. Additionally, an automatic labeling method was developed based on a reference pelvic model, including reference anatomical landmarks, matching the individual pelvic models. (3) Results: Heterogeneity among landmarks in radiologists' labeling accuracy was observed, with some landmarks being rarely mislabeled by more than 4 mm and others being frequently mislabeled by 10 mm or more. The propagation to the pelvimetry measures was limited; only one out of the 15 measures reported a median error above 5 mm or 5°, and all measures showed moderate to excellent inter-radiologist reliability. The automatic method outperformed manual labeling. (4) Conclusions: This study confirmed the suitability of pelvimetry measures based on manual labeling of 3D pelvic models. Automatic labeling offers promising perspectives to decrease the demand on radiologists, standardize the labeling, and describe the pelvic cavity in more detail.

Spatial Distribution of Recurrence and Long-Term Toxicity Following Dose Escalation to the Dominant Intra-Prostatic Nodule for Intermediate-High-Risk Prostate Cancer: Insights from a Phase I/II Study.

Objectives: We investigated spatial patterns between primary and recurrent tumor sites and assessed long-term toxicity after dose escalation stereotactic body radiation therapy (SBRT) to the dominant intra-prostatic nodule (DIN). Materials and methods: In 33 patients with intermediate-high-risk prostate cancer (PCa), doses up to 50 Gy were administered to the DIN. Recurrence sites were determined and compared to the original tumor development sites through multiparametric MRI and 68Ga-labeled prostate-specific membrane antigen (PSMA) positron emission tomography/computed tomography (68Ga-PSMA-PET/CT) images. Overlap rates, categorized as 75% or higher for full overlap, and 25-74% for partial overlap, were assessed. Long-term toxicity is reported. Results: All patients completed treatment, with only one receiving concomitant androgen deprivation therapy (ADT). Recurrences were diagnosed after a median of 33 months (range: 17-76 months), affecting 13 out of 33 patients (39.4%). Intra-prostatic recurrences occurred in 7 patients (21%), with ≥75% overlap in two, a partial overlap in another two, and no overlap in the remaining three patients. Notably, five patients with intra-prostatic recurrences had synchronous bone and/or lymph node metastases, while six patients had isolated bone or lymph node metastasis without intra-prostatic recurrences. Extended follow-up revealed late grade ≥ 2 GU and GI toxicity in 18% (n = 6) and 6% (n = 2) of the patients. Conclusions: Among patients with intermediate-high-risk PCa undergoing focal dose-escalated SBRT without ADT, DIN recurrences were infrequent. When present, these recurrences were typically located at the original site or adjacent to the initial tumor. Conversely, relapses beyond the DIN and in extra-prostatic (metastatic) sites were prevalent, underscoring the significance of systemic ADT in managing this patient population. Advances in knowledge: Focal dose-escalated prostate SBRT prevented recurrences in the dominant nodule; however, extra-prostatic recurrence sites were frequent.

Anorectal Malformations: Finding the Pathway out of the Labyrinth.

Anorectal malformations (ARMs) are a complex group of congenital anomalies involving the distal anus and rectum, as well as the urinary and genital tracts in a significant number of cases. Most ARMs result from abnormal development of the urorectal septum in early fetal life. In most cases, the anus is not perforated and the distal enteric component ends blindly (atresia) or as a fistula into the urinary tract, genital tract, or perineum. ARMs are also present in a great number of syndromes and associations of congenital anomalies. The classification of ARMs is mainly based on the position of the rectal pouch relative to the puborectal sling, the presence or absence of fistulas, and the types and locations of the fistulas. All of this information is crucial in determining the most appropriate surgical approach for each case. Imaging studies play a key role in evaluation and classification of ARMs. In neonates, clinical and radiologic examinations in the first 3 days of life help determine the type of ARM and the need for early colostomy. In older children, preoperative pelvic magnetic resonance imaging is the most efficient diagnostic method for evaluating the size, morphology, and grade of development of the sphincteric musculature.

[Prostate cancer center: a multidisciplinary approach to accurately manage patients with prostate cancer]. / Centre de la prostate: une approche multidisciplinaire pour une prise en charge globale du patient.

The prostate cancer is a complex pathology involving oncological, functional and psychosocial items. The prostate's center of CHUV harmonize the know-how of urologists, oncologist, radiotherapists and clinical nurses to offer a global management to patients attempts by prostate cancer, from diagnosis to therapy and follow-up.

Do cancer detection rates differ between transperineal and transrectal micro-ultrasound mpMRI-fusion-targeted prostate biopsies? A propensity score-matched study.

INTRODUCTION: High-resolution micro-ultrasound (micro-US) is a novel precise imaging modality that allows targeted prostate biopsies and multiparametric magnet resonance imaging (mpMRI) fusion. Its high resolution relying on a 29 MHz transducer allows real-time visualisation of prostate cancer lesions; this might overcome the inaccuracy of conventional MRI-US fusion biopsy strategies. We compared cancer detection rates in patients who underwent transrectal (TR-B) versus transperineal (TP-B) MR-micro-US fusion biopsy. MATERIALS AND METHODS: 1:2 propensity score matching was performed in 322 consecutive procedures: 56 TR-B and 266 TP-B. All prostate biopsies were performed using ExactVuTM micro-US system with mpMRI image fusion. Clinically significant disease was defined as grade group ≥2. The primary objective was to evaluate the detection of clinically significant disease according to access route. The secondary outcomes were to compare the respective detection rates of random and targeted biopsies stratified per access route and to evaluate micro-US for its potential added value. RESULTS: 47 men undergoing TR-B and 88 undergoing TP-B were matched for age, PSA, clinical stage, prostate volume, PIRADS score, number of mpMRI-visible lesions and indication to biopsy. The detection rates of clinically significant and of any prostate cancer did not differ between the two groups (45% TR-B vs 42% TP-B; p = 0.8, and 57% TR-B vs 59% TP-B; p = 0.9, respectively). Detection rates also did not differ significantly between random (p = 0.4) and targeted biopsies (p = 0.7) stratified per access route. Micro-US targeted biopsy detected 36 MRI-invisible lesions in 33 patients; 19% of these lesions were positive for clinically significant disease. Overall, micro-US targeted biopsies upgraded 2% of patients to clinically significant disease that would have been missed otherwise. CONCLUSIONS: MR-micro-US-fusion TR-B and TP-B have similar diagnostic yields in terms of detection rates of clinically significant prostate cancer. Micro-US targeted biopsy appears to have an additional diagnostic value over systematic and MRI-targeted biopsies.

Exploration of the Acceptance of the Use of Procalcitonin Point-of-Care Testing and Lung Ultrasonography by General Practitioners to Decide on Antibiotic Prescriptions for Lower Respiratory Infections: A Qualitative Study.

OBJECTIVES: We aimed to explore the acceptance and opinions of general practitioners (GPs) on the use of procalcitonin point-of-care and lung ultrasonography for managing patients with lower respiratory tract infections in primary care. We suppose that there are several factors that can influence the physician's antibiotic prescribing decision, and the implementation of a new tool will only be possible when it can be inserted into the physician's daily practice, helping him/her in the decision-making process. DESIGN: Semistructured interviews; data analysis using the grounded theory method. SETTING: Lausanne, Switzerland. PARTICIPANTS: 12 GPs who participated in the randomised clinical trial UltraPro, which evaluated the impact of the use of procalcitonin only or an algorithm combining procalcitonin and lung ultrasonography on antibiotic prescription. RESULTS: GPs had mostly positive attitudes towards the use of point-of-care procalcitonin in lower respiratory tract infections and uncertainties regarding the usefulness of ultrasonography. Physicians' prescribing decisions result from interactions between three kinds of TrustS (core category): 'self-confidence', 'trust in the results' and 'trust in the doctor-patient relationship'. Procalcitonin reinforced the three levels of trust, while ultrasonography only strengthened the physician-patient relationship. To facilitate implementation of procalcitonin, physicians pointed out the need of coverage by insurance and of clear guidelines describing the targeted patient population. CONCLUSIONS: Our data show that there is a preference for the implementation of procalcitonin rather than lung ultrasonography for the management of patients with lower respiratory tract infections in primary care. Coverage by insurance plans and updated guidelines are prerequisite to the successful implementation of procalcitonin testing in primary care. TRIAL REGISTRATION NUMBER: NCT03191071.

Overruling of Procalcitonin-Guided Antibiotics for Lower Respiratory Tract Infections in Primary Care: Ancillary Study of a Randomized Controlled Trial.

BACKGROUND: Lower respiratory tract infections (LRTIs) in primary care are a promising target for antibiotic stewardship. A clinical trial in Switzerland showed a large decrease in antibiotic prescriptions with procalcitonin guidance (cut-off < 0.25 µg/L) compared with usual care. However, one-third of patients with low procalcitonin at baseline received antibiotics by day 28. AIM: To explore the factors associated with the overruling of initial procalcitonin guidance. DESIGN AND SETTING: Secondary analysis of a cluster randomized trial in which patients with an LRTI were included. METHOD: Using the characteristics of patients, their disease, and general practitioners (GPs), we conducted a multivariate logistic regression, adjusted for clustering. RESULTS: Ninety-five out of 301 (32%) patients with low procalcitonin received antibiotics by day 28. Factors associated with an overruling of procalcitonin guidance were: a history of chest pain (adjusted OR [aOR] 1.81, 95% confidence interval 1.03-3.17); a prescription of chest X-ray by the GP (aOR 4.65, 2.32-9.34); a C-reactive protein measured retrospectively above 100 mg/L (aOR 7.48, 2.34-23.93, reference ≤ 20 mg/L); the location of the GP practice in an urban setting (aOR 2.27, 1.18-4.37); and the GP's number of years of experience (aOR per year 1.05, 1.01-1.09). CONCLUSIONS: Overruling of procalcitonin guidance was associated with GPs' socio-demographic characteristics, pointing to the general behavioral problem of overprescription by physicians. Continuous medical education and communication training might support the successful implementation of procalcitonin point-of-care tests aimed at antibiotic stewardship.