Multi-center validation of an artificial intelligence system for detection of COVID-19 on chest radiographs in symptomatic patients.

OBJECTIVES: While chest radiograph (CXR) is the first-line imaging investigation in patients with respiratory symptoms, differentiating COVID-19 from other respiratory infections on CXR remains challenging. We developed and validated an AI system for COVID-19 detection on presenting CXR. METHODS: A deep learning model (RadGenX), trained on 168,850 CXRs, was validated on a large international test set of presenting CXRs of symptomatic patients from 9 study sites (US, Italy, and Hong Kong SAR) and 2 public datasets from the US and Europe. Performance was measured by area under the receiver operator characteristic curve (AUC). Bootstrapped simulations were performed to assess performance across a range of potential COVID-19 disease prevalence values (3.33 to 33.3%). Comparison against international radiologists was performed on an independent test set of 852 cases. RESULTS: RadGenX achieved an AUC of 0.89 on 4-fold cross-validation and an AUC of 0.79 (95%CI 0.78-0.80) on an independent test cohort of 5,894 patients. Delong's test showed statistical differences in model performance across patients from different regions (p < 0.01), disease severity (p < 0.001), gender (p < 0.001), and age (p = 0.03). Prevalence simulations showed the negative predictive value increases from 86.1% at 33.3% prevalence, to greater than 98.5% at any prevalence below 4.5%. Compared with radiologists, McNemar's test showed the model has higher sensitivity (p < 0.001) but lower specificity (p < 0.001). CONCLUSION: An AI model that predicts COVID-19 infection on CXR in symptomatic patients was validated on a large international cohort providing valuable context on testing and performance expectations for AI systems that perform COVID-19 prediction on CXR. KEY POINTS: • An AI model developed using CXRs to detect COVID-19 was validated in a large multi-center cohort of 5,894 patients from 9 prospectively recruited sites and 2 public datasets. • Differences in AI model performance were seen across region, disease severity, gender, and age. • Prevalence simulations on the international test set demonstrate the model's NPV is greater than 98.5% at any prevalence below 4.5%.

Fetal MRI prior to intrauterine surgery of open neural tube defects: What does the radiologist need to know.

The management of myelomeningocele study trial showed significant prognostic improvement in fetal repair before 26 weeks of gestation. Hence, surgery in utero represents the best treatment option for open-neural tube defects (NTDs). Fetal surgery of open-NTDs has specific inclusion and exclusion criteria, which can be adequately studied with fetal MRI. The main concern: the spine (spinal defects other than Myelomeningocele and Myeloschisis, the level of the lesion higher than T1 or lower than S1 and the degree of kyphosis ≥ 30°), the skull/brain (no cerebellum herniation and Chiari II malformation and the presence of any intracranial abnormality unrelated to open NTDs), the uterus (cervix length less than 2 cm, multiple gestations and placental and uterine abnormalities) and any other fetal abnormality not attributed to spinal defect. In this review, we describe the fundamental role of fetal MRI in supporting therapeutic decisions in pre-surgery intrauterine planning through the accurate and comprehensive description of findings, providing a proposal of a structured report. In addition, we describe how post-surgical MRI is important in investigating the effectiveness of surgery and detecting repairing complications.

[When a Headache Is Not Just Hypertension: A Case of Atypical Hemolytic Uremic Syndrome in a Young Patient].

Thrombotic microangiopathies represent a group of particularly serious pathologies that can cause a rapid worsening of renal function, especially in young subjects. Through the clinical case described, we will focus our attention on the clinical and laboratory manifestations of the pathology, on the diagnostics and on the therapies to be used. Recent therapeutic innovations for the treatment of this pathology will also be analysed.

[Acute Kidney Injury Caused by Mushrooms: A Case Report of Amanita Echinocephala Ingestion].

Mushroom poisoning can represent an acute event which the clinical nephrologist must deal with and which often leads to the need for emergency dialysis treatment. Through the exposed clinical case, we describe the secondary clinical manifestations of an acute intoxication sustained by Amanita Echinocephalae, and we will provide an overview of the main fungal intoxications of renal interest, the clinical presentation, the diagnostic strategies, and the subsequent treatment.

[When a rear-end collision turns out to be a revelation: a case of IgG4 related kidney desease].

IgG4 related renal disease represents a frequent manifestation of the wider IgG4 related disease, a fibroinflammatory disorder with a not fully understood etiology that affects several organs. Through the clinical case presented, we will focus attention on this pathology and on the diagnostic difficulties that may arise, and on the investigations necessary for the diagnosis. Finally, the main therapeutic options will be discussed.

[Kidney Transplant in a Highly Sensitized Patient Treated with Imlifidase].

Through a clinical case, we will describe the difficulties associated with providing transplantation opportunities to highly immunized patients. We will therefore focus on new desensitization therapies and their pharmacological effects with the consequent improvement in clinical outcomes. The main desensitization strategies in use and the main future therapeutic prospects will also be discussed.

Features of cystadenofibroma on magnetic resonance imaging: an update using the O-RADS lexicon and considering diffusion-weighted and perfusion imaging.

PURPOSE: Cystadenofibroma (CAF) is a rare tumour of the ovary that can be confused with a borderline or malignant lesion due to its morphological characteristics. The study aims to analyse the MRI (magnetic resonance imaging) features of histologically proven ovarian cystadenofibromas according to lexicon-based and O-RADS (Ovarian-Adnexal Reporting and Data System) descriptors, with particular attention to time-intensity curves (TIC) and Diffusion-Weighted sequences (DWI); we also wanted to test the performance of O-RADS MRI risk stratification system in this particular subgroup of patients. METHODS: We have included all patients who performed MR between October 2019 and December 2021 after an inconclusive trans-vaginal ultrasound. All patients underwent surgery with histological results of CAF. According to the O-RADS lexicon, we reported the morphological characteristics of each lesion and their appearance in the perfusion-weighted imaging (PWI) and DWI sequences. We assessed the risk of malignancy for each lesion through O-RADS MRI score. RESULTS: Twenty-one histologically proven CAF were analysed, of which 20 benign and one borderline with degeneration into adenocarcinoma. We described the typical morphological characteristics of CAF according to lexicon-based and O-RADS descriptors. Analysis of time-intensity curves (TIC) in PWI sequences showed a slow and progressive enhancement of solid tissue (type I curve), configuring an O-RADS score of 2 or 3, except for the only malignant lesion that showed a type II curve and restriction in DWI (O-RADS 4). CONCLUSIONS: Our study is the largest comprising PWI and DWI sequences, highlighting their pivotal role. O-RADS score correctly classified the masses as benign or malignant.

[Rapidly progressive Alport syndrome in a young woman: case report].

Alport syndrome is a hereditary clinical condition characterized by multisystemic changes (sensorineural and ocular deafness) associated with hematuria and proteinuria. Due to its genetic variability and multiple symptoms, it is often diagnosed by chance and too late. The present work focuses on this pathology through a clinical case report. It also mentions the new therapeutic possibilities relating to this disease.

[Multiple myeloma, plasma cell dyscrasias and kidneys: a few symptoms, extensive damage].

Multiple myeloma represents one of the main universal oncological diseases. Due to its clinical characteristics, it is often diagnosed only too late, when it has already determined systemic effects; this results in greater therapeutic difficulty and worse prognostic results. Through the clinical case discussed in this article, we want to focus on the often aspecific manifestations of this pathology and on the need for a correct clinical and diagnostic framework. The main renal manifestations secondary to the deposition of immunoglobulins in both the glomerular and tubular areas will also be examined.

Multimodality imaging of COVID-19 pneumonia: from diagnosis to follow-up. A comprehensive review.

Due to its pandemic diffusion, SARS- CoV-2 (Severe Acute Respiratory Syndrome Coronavirus 2) infection represents a global threat. Despite a multiorgan involvement has been described, pneumonia is the most common manifestation of COVID-19 (Coronavirus disease 2019) and it is associated with a high morbidity and a considerable mortality. Especially in the areas with high disease burden, chest imaging plays a crucial role to speed up the diagnostic process and to aid the patient management. The purpose of this comprehensive review is to understand the diagnostic capabilities and limitations of chest X-ray (CXR) and high-resolution computed tomography (HRCT) in defining the common imaging features of COVID-19 pneumonia and correlating them with the underlying pathogenic mechanisms. The evolution of lung abnormalities over time, the uncommon findings, the possible complications, and the main differential diagnosis occurring in the pandemic phase of SARS-CoV-2 infection are also discussed.

[Leptospirosis and kidneys: a clinical case].

We describe here the case of a young patient, employed in agriculture, who entered the emergency room with fever, headache, hematuria and a worsening of renal function; we diagnosed leptospirosis with renal involvement. As the patient lamented very generic symptoms, the anamnesis was fundamental in leading us to suspect an infection, execute the right laboratory analysis, and correctly diagnose a pathology which is currently very rare in Italy.

[Hemodialysis treatment as a trigger cause of cryoglobulinemic purpura: a case report].

We describe the clinical case of a patient who developed mixed cryoglobulinemia syndrome after hemodialysis treatment with dialysate temperature lower than 36°C despite the negativization of the viral genome for HCV after eradication therapy.