INQUADRAMENTO CLINICO E MANAGEMENT DELLO SCHWANNOMA ESCLUSIVAMENTE INTRALABIRINTICO

Lo schwannoma intralabirintico (SIL) è un raro tumore benigno (prevalenza 0.1-0.4%) che origina dalle cellule di Schwann situate a ridosso della giunzione cito-neurale dell’VIII n.c. I sintomi clinici includono ipoacusia neurosensoriale monolaterale progressiva (95%), acufeni (51%), disequilibrio (35%), vertigine (22%), fullness (2%). Alla risonanza magnetica (RM) il tumore si presenta come una massa circoscritta, iperintensa in T1, ipointensa in T2 e con enhancement dopo gadolinio nelle immagini T1-pesate. Il management prevede in prima istanza osservazioni seriali con RM “wait and scan approach”. La chirurgia, considerando le complicanze descritte quali anacusia (100%), paralisi VII n.c. (4%), fistola liquorale (5.4%), meningite (1.8%), è riservata a casi limitati e dipende da: età, condizioni generali del paziente, sede e dimensioni del tumore ed è consigliabile in caso di un pattern di crescita invasivo e presenza di sintomi vertiginosi non responsivi al trattamento medico

Cholesteatoma vs granulation tissue: a differential diagnosis by DWI-MRI apparent diffusion coefficient

To diagnose cholesteatoma when it is not visible through tympanic perforation, imaging techniques are necessary. Recently, the combination of computed tomography and magnetic resonance imaging has proven effective to diagnose middle ear cholesteatoma. In particular, diffusion weighted images have integrated the conventional imaging for the qualitative assessment of cholesteatoma. Accordingly, the aim of this study was to obtain a quantitative analysis of cholesteatoma calculating the apparent diffusion coefficient value. So, we investigated whether it could differentiate cholesteatoma from other inflammatory tissues both in a preoperative and in a postoperative study

Skull Base Fungal Osteomyelitis: A Case Report and Review of the Literature

Skull base osteomyelitis (SBO) is an invasive infection refractory to therapy, closely linked with malignant otitis externa (MOE). It is characterized by a mild clinical presentation that can delay cross-sectional imaging considered as the key to revealing it. Skull base osteomyelitis typically affects elderly diabetics and immunocompromised patients (>70 years). It most commonly has an otogenic origin due to an extension of MOE. The prognosis can be very poor without the administration of adequate and timely therapy at an early disease stage. Nowadays, Pseudomonas aeruginosa remains the most common pathogen associated with SBO. Fungi are a rare cause of MOE. This report documents a rare case of otogenic SBO caused by Candida parapsilosis in a diabetic patient, with persistent otologic symptoms as clinical onset and resistance to medical treatment. Fungal MOE has more subtle symptoms and is more aggressive than its bacterial counterpart. When MOE is resistant to antibacterial drugs, this should raise the suspicion of a fungal etiology of MOE. The current guidelines do not exhaustively describe the diagnosis, antifungal drugs of choice, and optimum duration of treatment. The description of these rare clinical cases should help with the multidisciplinary management of this disease in order to optimize the diagnosis and therapeutic protocol

Thromboembolic and bleeding risk in atrial fibrillation patients with chronic kidney disease: role of anticoagulation therapy

Atrial fibrillation (AF) and chronic kidney disease (CKD) are strictly related; several independent risk factors of AF are often frequent in CKD patients. AF prevalence is very common among these patients, ranging between 15% and 20% in advanced stages of CKD. Moreover, the results of several studies showed that AF patients with end stage renal disease (ESRD) have a higher mortality rate than patients with preserved renal function due to an increased incidence of stroke and an unpredicted elevated hemorrhagic risk. Direct oral anticoagulants (DOACs) are currently contraindicated in patients with ESRD and vitamin K antagonists (VKAs), remaining the only drugs allowed, although they show numerous critical issues such as a narrow therapeutic window, increased tissue calcification and an unfavorable risk/benefit ratio with low stroke prevention effect and augmented risk of major bleeding. The purpose of this review is to shed light on the applications of DOAC therapy in CKD patients, especially in ESRD patients

Stem Cell Modeling of Neuroferritinopathy Reveals Iron as a Determinant of Senescence and Ferroptosis during Neuronal Aging

Neuroferritinopathy (NF) is a movement disorder caused by alterations in the L-ferritin gene that generate cytosolic free iron. NF is a unique pathophysiological model for determining the direct consequences of cell iron dysregulation. We established lines of induced pluripotent stem cells from fibroblasts from two NF patients and one isogenic control obtained by CRISPR/Cas9 technology. NF fibroblasts, neural progenitors, and neurons exhibited the presence of increased cytosolic iron, which was also detectable as: ferritin aggregates, alterations in the iron parameters, oxidative damage, and the onset of a senescence phenotype, particularly severe in the neurons. In this spontaneous senescence model, NF cells had impaired survival and died by ferroptosis. Thus, non-ferritin-bound iron is sufficient per se to cause both cell senescence and ferroptotic cell death in human fibroblasts and neurons. These results provide strong evidence supporting the primary role of iron in neuronal aging and degeneration

An ex vivo model contributing to the diagnosis and evaluation of new drugs in cystic fibrosis

La fibrosi cistica (FC) è una malattia autosomica recessiva causata da mutazioni nel gene CFTR (Cystic Fibrosis Transmembrane conductance Regulator). Finora sono state descritte circa 2000 mutazioni, ma per la maggior parte di esse è difficile definirne leffetto senza complesse procedure in vitro. Abbiamo effettuato il campionamento (mediante brushing), la cultura e lanalisi di cellule epiteliali nasali umane (HNEC) utilizzando una serie di tecniche che possono aiutare a testare leffetto delle mutazioni CFTR. Abbiamo eseguito 50 brushing da pazienti FC e controlli, e in 45 casi si è ottenuta una coltura positiva. Utilizzando cellule in coltura: i) abbiamo dimostrato lespressione ampiamente eterogenea del CFTR nei pazienti e nei controlli; ii) abbiamo definito leffetto di splicing di una mutazione sul gene CFTR; iii) abbiamo valutato lattività di gating di CFTR in pazienti portatori di differenti mutazioni; iv) abbiamo dimostrato che il butirrato migliora in modo significativo lespressione di CFTR. I dati provenienti dal nostro studio sperimentale dimostrano che luso del modello ex-vivo di cellule epiteliali nasali è un importante e valido strumento di ricerca e di diagnosi nella studio della FC e può anche essere mirato alla sperimentazione ed alla verifica di nuovi farmaci. In definitiva, in base ai nostri dati è possibile esprimere le seguenti conclusioni: 1) il prelievo delle cellule epiteliali nasali mediante brushing è applicabile senza alcuna anestesia ed è ben tollerato da tutti i pazienti affetti da FC (bambini e adulti), è scarsamente invasivo e facilmente ripetibile, è anche in grado di ottenere una sufficiente quantità di HNECs rappresentative, ben conservate, idonee allo studio della funzionalità di CFTR; 2) la conservazione delle cellule prelevate è possibile fino a 48 ore prima che si provveda allallestimento della coltura e ciò permette di avviare studi multicentrici con prelievi in ogni sede e quindi di ottenere una ampia numerosità campionaria; 3) la coltura di cellule epiteliali nasali può essere considerata un modello adatto a studiare leffetto molecolare di nuove mutazioni del gene CFTR e/o mutazioni specifiche di pazienti carriers dal significato incerto; 4) il modello ex-vivo delle HNECs consente inoltre di valutare, prima dellimpiego nelluomo, leffetto di farmaci (potenziatori e/o correttori) sulle cellule di pazienti portatori di mutazioni specifiche di CFTR; tali farmaci possono modulare lespressione genica del canale CFTR aprendo così nuove frontiere terapeutiche e migliori prospettive di vita per pazienti affetti da una patologia cronica come la Fibrosi Cistica; 5) la metodologia da noi istituita risulta essere idonea alla misura quantitativa, mediante fluorescenza, dellattività di gating del canale CFTR presente nelle membrane delle cellule epiteliali nasali prelevate da pazienti portatori di differenti genotipi; in tal modo è possibile individuare: a) pazienti FC portatori di 2 mutazioni gravi con unattività < 10% (in rapporto ai controlli -100%), b) soggetti FC portatori contemporaneamente di una mutazione grave e di una lieve con unattività tra 10-30%, c) i cosiddetti portatori carriers- eterozigoti - con unattività tra 40-70%. In conclusione la possibilità di misurare lattività del canale CFTR in HNECs fornisce un importante contributo alla diagnosi di FC, mediante individuazione di un cut-off diagnostico, ed anche alla previsione della gravità fenotipica della malattia; quindi quanto rilevabile dalla misura del suddetto canale permette di prospettare per il futuro la possibilità di valutare meglio i pazienti per i quali il test del sudore ha dato risultati ambigui (borderline o negativi). La metodica da noi sperimentata consente anche di monitorare i pazienti durante il trattamento farmacologico, valutando in tal modo i reali effetti delle nuove terapie

Mutation and polymorphism spectrum in osteogenesis imperfecta type II: implications for genotype–phenotype relationships

Osteogenesis imperfecta (OI), also known as brittle bone disease, is a clinically and genetically heterogeneous disorder primarily characterized by susceptibility to fracture. Although OI generally results from mutations in the type I collagen genes, COL1A1 and COL1A2, the relationship between genotype and phenotype is not yet well understood. To provide additional data for genotype–phenotype analyses and to determine the proportion of mutations in the type I collagen genes among subjects with lethal forms of OI, we sequenced the coding and exon-flanking regions of COL1A1 and COL1A2 in a cohort of 63 subjects with OI type II, the perinatal lethal form of the disease. We identified 61 distinct heterozygous mutations in type I collagen, including five non-synonymous rare variants of unknown significance, of which 43 had not been seen previously. In addition, we found 60 SNPs in COL1A1, of which 17 were not reported previously, and 82 in COL1A2, of which 18 are novel. In three samples without collagen mutations, we found inactivating mutations in CRTAP and LEPRE1, suggesting a frequency of these recessive mutations of ∼5% in OI type II. A computational model that predicts the outcome of substitutions for glycine within the triple helical domain of collagen α1(I) chains predicted lethality with ∼90% accuracy. The results contribute to the understanding of the etiology of OI by providing data to evaluate and refine current models relating genotype to phenotype and by providing an unbiased indication of the relative frequency of mutations in OI-associated genes

Inter-fractional monitoring of 12 C ions treatments: results from a clinical trial at the CNAO facility

The high dose conformity and healthy tissue sparing achievable in Particle Therapy when using C ions calls for safety factors in treatment planning, to prevent the tumor under-dosage related to the possible occurrence of inter-fractional morphological changes during a treatment. This limitation could be overcome by a range monitor, still missing in clinical routine, capable of providing on-line feedback. The Dose Profiler (DP) is a detector developed within the INnovative Solution for In-beam Dosimetry in hadronthErapy (INSIDE) collaboration for the monitoring of carbon ion treatments at the CNAO facility (Centro Nazionale di Adroterapia Oncologica) exploiting the detection of charged secondary fragments that escape from the patient. The DP capability to detect inter-fractional changes is demonstrated by comparing the obtained fragment emission maps in different fractions of the treatments enrolled in the first ever clinical trial of such a monitoring system, performed at CNAO. The case of a CNAO patient that underwent a significant morphological change is presented in detail, focusing on the implications that can be drawn for the achievable inter-fractional monitoring DP sensitivity in real clinical conditions. The results have been cross-checked against a simulation study