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Internuclear ophthalmoplegia (INO) is a horizontal gaze disorder caused by medial longitudinal fasciculus lesions. INO of abduction is an exceptionally rare variant characterized by abduction limitation with preserved convergence and contralateral adduction nystagmus, with unclear pathophysiology, and only a limited number of cases have been reported. A 27-year-old man presented with headache, vomiting, seizures, and altered sensorium. Examination revealed bilateral disc edema and abduction restriction of the right eye, with contralateral adduction nystagmus, consistent with INO of abduction. Brain MRI showed no brainstem lesions, while MR venography demonstrated cerebral venous thrombosis of the superior sagittal, left transverse, and sigmoid sinuses. Vitamin B12 deficiency with hyperhomocysteinemia was detected. Treatment with anticoagulation and acetazolamide resulted in complete resolution of the ocular motility deficits. This case highlights a reversible form of INO of abduction associated with raised intracranial pressure in the absence of structural brainstem lesions, likely due to pressure-mediated disruption of inhibitory gaze pathways. INO of abduction is an ultrarare but clinically important sign. Its recognition in patients with intracranial hypertension and normal brainstem imaging may aid in localization and facilitate timely, reversible treatment.

Hemiconvulsion-hemiplegia-epilepsy (HHE) syndrome is a rare complication of prolonged focal status epilepticus in childhood. The typical course follows a complex febrile convulsion and status epilepticus, typically in a child under 4 years of age, accompanied by cytotoxic edema of one hemisphere, evolving secondarily to atrophy and refractory seizures. We present a case series from Mayotte Island, providing a clinical and radiological chronological picture of this neurological disorder, with Magnetic Resonance Imaging (MRI) and Computed Tomography (CT) scans taken at different stages of the disease. HHE syndrome is a rare clinic-radiological syndrome that complicates prolonged febrile illness. Understanding the spontaneous evolution of this pathology makes it possible to limit explorations and even to project on the long-term prognosis, in the absence of known therapies.

Pheochromocytomasand paragangliomas (PPGLs) are rare catecholamine-secreting tumors that can affect systemic physiology, including bone metabolism. Although they are typically associated with genetic syndromes such as MEN2 and von Hippel-Lindau disease, PPGLs are not commonly linked to primary bone tumors. However, recent findings suggest a novel cancer syndrome involving both PPGLs and giant cell tumor of bone (GCTB) through H3F3A mutations. We report a rare case of a 53-year-old woman with multicentric GCTB, initially diagnosed at age 24, who subsequently developed bilateral pheochromocytomas. Following multiple recurrences of skeletal tumors and eventual leg amputation, imaging and biochemical evaluation revealed bilateral adrenal tumors with markedly elevated catecholamine levels. Genetic analysis identified mosaicism for a pathogenic H3F3A (G35W) variant in both adrenal and bone tumors. Surgical resection of both adrenal glands normalized catecholamine levels and resolved hypertension. The patient has remained tumor-free and normotensive for five years following adrenalectomy. This case supports the existence of a shared pathogenic mechanism linking PPGLs and GCTBs, likely mediated by postzygotic H3F3A mutations. Recognition of this association is crucial for early diagnosis, genetic counseling, and management of similar cases.

The development of clinical artificial intelligence models is constrained by limited access to high-quality electronic health record data, a challenge that is particularly pronounced in rare and highly imbalanced clinical cohorts. Synthetic data generation has been proposed as a strategy to mitigate data-sharing barriers. However, an integrated evaluation framework that jointly examines distributional fidelity, diagnostic behavior, and privacy risk under such conditions remains lacking. We developed an integrated evaluation framework to assess variational autoencoders (VAE) and conditional generative adversarial networks (CTGAN). The framework jointly characterizes distributional fidelity, privacy risk, and diagnostic behavior using structured electronic health record data from the KoGES cohort, with disease prevalence ranging from 0.8% to 7.5%, adopting a prevalence-aware approach in which evaluation metrics are stratified by disease-specific class frequency. To address the sensitivity of p-value-based tests in large samples, distance-based metrics, including Jensen-Shannon divergence and Wasserstein distance, were employed. Diagnostic behavior was evaluated using XGBoost, random forest, and logistic regression classifiers, with emphasis on minority-class-sensitive metrics such as recall and Macro-F1. In multivariate structural analyses, the correlation similarity between empirical and synthetic data was 0.794 for VAE-generated data and 0.667 for CTGAN-generated data. Across diseases with moderate outcome prevalence, multivariate and stratified distributions exhibited numerical overlap between VAE-generated and empirical data. In diagnostic evaluations, classifiers trained on empirical data alone yielded zero recall for the rarest outcome (0.8% prevalence), whereas CTGAN-trained classifiers produced non-zero recall values at the cost of reduced overall accuracy. Across evaluated threat models, membership inference attack performance remained near the random-guessing reference (AUROC ≈ 0.500). This study presents an integrated, prevalence-aware evaluation framework for synthetic clinical data that systematically identified failure modes undetectable by conventional single-metric approaches, including minority-class metric instability, heterogeneous tail-end privacy exposure, and qualitative divergence in membership score calibration. The evaluated generative models exhibited distinct trade-off profiles: VAE preserved multivariate structure while exhibiting lower proximity-based exposure under the evaluated threat model, whereas CTGAN achieved higher minority-class detection at the cost of structural fidelity. Supplementary augmentation experiments confirmed that increased synthetic data volume does not uniformly improve minority-class detection under extreme prevalence constraints. These findings demonstrate that numerical overlap between synthetic and empirical distributions does not guarantee clinical equivalence, underscoring the need for prevalence-stratified, multi-dimensional validation in structured EHR research. Not applicable.

Posterior Reversible Encephalopathy Syndrome (PRES) is a clinico-radiological condition characterized by acute neurological symptoms associated with vasogenic cerebral edema. Although increasingly recognized in pediatric populations, PRES remains exceptionally rare in infants younger than six months, making diagnosis particularly challenging in this age group. We report the case of a 4-month-old previously healthy infant admitted for recurrent afebrile generalized tonic-clonic seizures. Initial clinical examination, laboratory investigations, cerebrospinal fluid analysis, and cranial computed tomography were unremarkable. Brain magnetic resonance imaging revealed bilateral, symmetrical cortico-subcortical occipital hyperintensities on T2-weighted and FLAIR sequences, with diffusion-weighted hyperintensity and mildly reduced ADC signal, overall suggestive of PRES with a possible superimposed cytotoxic component. No sustained arterial hypertension or underlying metabolic, infectious, autoimmune, or toxic cause was identified despite extensive evaluation, supporting the diagnosis of idiopathic PRES. Seizures were controlled with antiepileptic therapy, and the clinical course was favorable without early recurrence. This case highlights an exceptionally early presentation of idiopathic PRES in infancy and underscores the need to consider this diagnosis in unexplained seizures, even in the absence of classical risk factors. Early MRI is essential for diagnosis, and long-term neurodevelopmental follow-up remains crucial given the uncertain prognosis in this age group.

Rare earth elements (REEs), comprising the lanthanides, scandium, and yttrium, are increasingly released into the environment due to anthropogenic activities but are not routinely monitored as conventional environmental contaminants. Gadolinium (Gd), used as a contrast agent in magnetic resonance imaging, is continuously discharged into aquatic ecosystems. While Gd effects on plants have been partially explored, its impact on plant physiology and plant-microbiome interactions remains poorly understood. This study investigated the effects of 150 µM Gd (23.6 mg L- 1, 23.6 ppm) on tomato plants (Solanum lycopersicum L.) grown in hydroponics using a phosphate-free nutrient solution to prevent Gd precipitation and ensure its bioavailability. A multidisciplinary approach was employed, integrating morphological, physiological, biochemical, and molecular analysis. Plant growth, root system architecture, antioxidant defence responses, calcium content, Gd accumulation and translocation were assessed, together with changes in the composition and predicted functional potential of the rhizosphere microbiome. Prolonged Gd exposure significantly impaired tomato growth reducing leaf fresh weight from 7.90 g in control plants to 3.15 g in treated seedlings and markedly altering root morphology. Stress conditions triggered strong oxidative responses, while Gd accumulated predominantly in roots (5.32 mg g- 1), with no detectable translocation to aerial tissues. Rhizosphere microbial community composition was severely altered (e.g., Burkholderiales declined to 42% in Gd-treated plants). This work represents one of the first integrated assessments of plant morphological, physiological, biochemical and microbiome-level responses of a crop plant and its rhizosphere microbiome to Gd exposure, providing new insights into the ecological and agronomic implications of emerging REEs contamination.

Pheochromocytoma is a rare neuroendocrine tumor in children, typically presenting with hypertension, headache, and palpitations. Presentation with abdominal pain as the sole initial symptom, rapidly progressing to catecholamine-induced cardiomyopathy, cardiogenic shock, and multiple organ dysfunction syndrome (MODS), is exceedingly uncommon and poses significant diagnostic and therapeutic challenges. We report a case of adolescent pheochromocytoma multisystem crisis to highlight the diagnostic pitfalls, pathophysiological cascade, and the dilemma of extracorporeal life support. A 13-year-8-month-old male presented with a 3-day history of abdominal pain and poor responsiveness. Initial treatment for acute gastroenteritis was ineffective, and his condition rapidly deteriorated into cardiogenic shock and multiple organ failure, requiring mechanical ventilation and veno-arterial extracorporeal membrane oxygenation (VA-ECMO) prior to transfer to our hospital. The clinical course was characterized by sustained abdominal pain as the initial manifestation, absence of typical palpitations or headache, transient hypertension (175/109 mmHg) followed by circulatory collapse, and physical findings of a sedated state, mottled skin with extremity ecchymoses, muffled heart sounds, absent bowel sounds, and prolonged capillary refill time of 5 s. Bedside echocardiography revealed a left ventricular ejection fraction of only 26%. Abdominal computed tomography and ultrasonography demonstrated a left adrenal mass. Plasma normetanephrine was markedly elevated at >&#x2009;20.56 nmol/L (normal&#x2009;&#x2264;&#x2009;0.9 nmol/L) and 3-methoxytyramine at 5.47 nmol/L (normal&#x2009;<&#x2009;0.18 nmol/L), confirming the diagnosis of pheochromocytoma. VA-ECMO and mechanical ventilation were maintained. Multiple sessions of plasma exchange and continuous renal replacement therapy were instituted, alongside vasoactive agents. Surgical resection was planned but never performed due to progressive multiorgan deterioration. Despite 6 days of ECMO support and comprehensive therapy, the patient developed hepatic encephalopathy and digital dry gangrene. The family elected to withdraw care, and the patient died shortly after discharge. This case illustrates that pheochromocytoma can present with abdominal pain as the sole initial symptom in adolescents, mimicking acute gastroenteritis. The rapid progression from catecholamine storm to irreversible multiorgan failure underscores the critical importance of early recognition of atypical presentations. While VA-ECMO may serve as a bridge to diagnosis and stabilization, it cannot reverse established multiorgan injury when timely surgical source control is not achieved.

Jugulotympanic paragangliomas (JTPs) are rare, hypervascular skull base tumors. Surgery and stereotactic radiosurgery (SRS) are often framed as competing options, yet outcome data from Latin American public referral centers are scarce. We evaluated a function-first surgical strategy and related tumor stage to outcomes. Retrospective single-center study of 24 consecutive patients with histopathologically confirmed JTP who underwent 32 resections (2016-2025), analyzed at patient and procedure level. Fisch class (A/B vs. C/D) was related to extent of resection, cranial nerve morbidity, and reoperation (Fisher's exact test, exploratory). Functional outcome (modified Rankin Scale) was assessed at 6 and 12 months; cranial nerve deficits were classified as transient or permanent. Mean age was 51 years; 83% were women. Advanced (Fisch C/D) tumors comprised 79%. Preoperative embolization was used in 88%. Gross total resection was achieved in 56% of procedures. New or worsened facial nerve injury occurred after 25% of procedures (permanent in 6 of 8 affected patients), and all facial injuries occurred in Fisch C/D tumors. Eight patients (33%) required unplanned reoperation; none were planned staged. There was no perioperative mortality. Functional outcome was favorable (median modified Rankin Scale score 1 at 12 months; mRS &#x2264;2 in 92%). After a median follow-up of 86 months, recurrence after gross total resection occurred in 4 patients and progression of residual disease in 2. In a predominantly advanced, public-referral cohort, a function-first surgical strategy with SRS reserved for residual or recurrent disease achieved good functional outcomes without mortality. Surgery and SRS are complementary rather than competing modalities.

Pediatric pulmonary embolism (PE) is a relatively rare but high-risk disease. There is minimal evidence to guide clinical management, particularly with respect to reperfusion therapies. Few studies capture bleeding outcomes to inform risk-benefit management decisions. In this single-center, retrospective cohort study, we aimed to describe pediatric patients <21 years of age who received acute PE care at our institution, excluding those with comorbid cardiac disease. We described the PE risk factors, in-hospital management, and acute outcomes, including bleeding and mortality. Between 2003 and 2022, 175 patients met eligibility: 120 low-risk (69%), 44 intermediate-risk (25%), and 11 high-risk (6%) PE. Most (N=142) received anticoagulation alone; 29 patients received reperfusion therapy for PE, the most common reperfusion therapy was systemic thrombolysis. There were 34 clinically relevant bleeding events in 27 patients, including major bleeding in 9 (5%) and clinically relevant non-major bleeding events in 18 (10%) patients. Sixty-two percent (21/34) of bleeding events occurred in patients receiving anticoagulation alone, while 10/34 (29%) occurred in patients receiving systemic thrombolysis. In the high-risk PE cohort, clinically relevant bleeding occurred in 73% and 45% died. Most patients with major bleeding had other bleeding risk factors independent of their PE-directed therapy. All-cause mortality was 4%, with 2% PE-related mortality. This cohort study highlights that reperfusion therapy is well-tolerated in select pediatric patients and rates of bleeding and death are high in high-risk PE. Future research should validate these findings with prospective, standardized bleeding outcome collection to inform management decisions in pediatric PE.

Artificial intelligence (AI) tools have the potential to enhance personalized clinical care, particularly in radiology. However, their integration into clinical workflows remains complex, especially in pediatric oncology, where early cancer detection is critical. Children with Li-Fraumeni Syndrome (LFS), a rare cancer predisposition disorder, undergo regular surveillance whole-body MRI (wbMRI), which presents an opportunity for AI-assisted tumour detection. We evaluated the feasibility of an AI-assisted overlay for highlighting tumour-like regions in pediatric surveillance wbMRI and explored how access to the overlay influenced radiologist workflow, candidate-lesion marking behaviour, follow-up recommendations, and perceived workload. We developed a patch-based AI segmentation model trained on augmented 2D slices from 675 surveillance wbMRI volumes of pediatric patients with LFS. The model was designed to highlight regions with high tumour probability. A reader study was conducted with two radiologists who independently reviewed wbMRI cases both with and without AI assistance. We measured evaluation time, number and location of tumours identified, type of follow-up recommendation, and subjective feedback using structured questionnaires. AI assistance altered interpretation workflows for both radiologists, with mixed effects. On average, the time required to evaluate each case increased when using the AI tool for both radiologists. However, one radiologist had an increase in the number of candidate lesion locations selected with the tool, and one had a decrease in the number of candidate lesion locations selected with the tool. Subjective feedback indicated that one of the radiologists found a greater difference in their perception between performing with the tool versus without the AI tool; however, both radiologists felt that the task was less difficult and less stressful with the AI tool. Inter-rater variability was evident, underscoring the need for personalized calibration of AI tools. AI-assisted wbMRI interpretation can improve tumour detection in pediatric cancer surveillance by reducing false negatives. However, its influence on workflow efficiency and inter-radiologist variability highlights the importance of careful implementation. Successful integration requires addressing challenges such as improving the predictive precision of AI models, offering intuitive end-user designs and instructions, and building trust in AI outputs. AI outputs can influence workflow and behaviour in reader-specific ways. Clinical translation will require larger, randomized, multi-reader studies and model refinement to reduce false positives and quantify lesion-level reader performance. This can help ensure better patient outcomes in addition to reduced clinician burnout.

Intestinal helminth infections in children remain a significant public health problem worldwide. Among these, those caused by cestodes can be misdiagnosed, as occurs with dipylidiasis, a zoonosis caused by Dipylidium caninum. Although common in dogs and cats, human infection is rare and may be misdiagnosed as Enterobius vermicularis due to overlapping symptoms. We present the case of a 3-year-old Spanish boy with intense anal itching, treated twice with mebendazole for presumed pinworm infection without improvement. Persistent symptoms, anorexia, and weight loss prompted a parasitological examination. Microscopic examination of whitish structures in the feces revealed gravid proglottids with bilateral genital pores and egg packets containing hexacanth embryos, confirming D. caninum infection. Epidemiological investigation suggested exposure to a relative's dog as the probable source. Treatment with paromomycin sulfate resulted in complete cure. This case highlights the importance of recognizing the characteristic morphology of D. caninum to avoid misdiagnosis and inappropriate therapy.

Colitis cystica profunda (CCP) is a rare benign lesion in humans that can mimic, clinically and radiologically, a malignant neoplasm. CCP etiopathogenesis is poorly understood and believed to be due to congenital ectopia or associated with chronic inflammation. Despite sporadic reports of CCP in animals, there are no established animal models for the study of this disease. Here, we briefly review CCP in humans and animals with a discussion of the possible etiopathogenesis and potential animal models.

Semaglutide, a glucagon-like peptide-1 receptor agonist (GLP-1 RA), is widely used for the management of type 2 diabetes, metabolic syndrome, and obesity. Concerns regarding its potential association with thyroid cancer, particularly medullary thyroid carcinoma, have emerged, although current human evidence remains inconclusive. Reports of papillary thyroid carcinoma (PTC) while using semaglutide therapy are exceedingly rare. We describe a 40-year-old man with metabolic syndrome and obesity who had been treated with semaglutide for several years before discontinuation. A routine chest computed tomography (CT) performed for an unrelated diaphragmatic hernia identified a suspicious thyroid lesion, later confirmed by ultrasound as a 1&#x2009;&#xd7;&#x2009;1&#xa0;cm irregular hypoechoic nodule in the left lobe with several small ipsilateral lymph nodes demonstrating suspicious features. Fine-needle aspiration cytology revealed classic PTC (Bethesda VI). The patient underwent total thyroidectomy with left selective neck dissection and central compartment dissection. Histopathology confirmed a unifocal classic variant PTC, 16&#xa0;mm in size, with negative margins, no lymph node involvement, and no extrathyroidal extension. After an uncomplicated postoperative course, he was prescribed levothyroxine for TSH suppression and discharged. This case of PTC discovered concomitantly while the patient was on semaglutide therapy highlights an important clinical scenario but does not provide evidence of causation. The totality of available human data continues to support the safety of semaglutide with respect to thyroid cancer risk. Further long-term surveillance and high-quality epidemiological studies remain warranted.