A conserved phenylalanine motif among Teleost fish provides insight for improving electromagnetic perception.

Magnetoreceptive biology as a field remains relatively obscure; compared to the breadth of species believed to sense magnetic fields, it remains under-studied. Here, we present grounds for the expansion of magnetoreception studies among Teleosts. We begin with the electromagnetic perceptive gene (EPG) from Kryptopterus vitreolus and expand to identify 72 Teleosts with homologous proteins containing a conserved three-phenylalanine (3F) motif. Phylogenetic analysis provides insight as to how EPG may have evolved over time, and indicates that certain clades may have experienced a loss of function driven by different fitness pressures. One potential factor is water type with freshwater fish significantly more likely to possess the functional motif version (FFF), and saltwater fish to have the non-functional variant (FXF). It was also revealed that when the 3F motif from the homolog of Brachyhypopomus gauderio (B.g.) is inserted into EPG - EPG(B.g.) - the response (as indicated by increased intracellular calcium) is faster. This indicates that EPG has the potential to be engineered to improve upon its response and increase its utility to be used as a controller for specific outcomes.

Intrapartum pyrexia, cardiotocography traces and histologic chorioamnionitis: a case-control study.

OBJECTIVES: To compare characteristics of labor, cardiotocography traces, and maternal and neonatal outcomes, in a cohort of pregnancies at term complicated by maternal intrapartum pyrexia, with or without a histologic diagnosis of chorioamnionitis. METHODS: This is a retrospective case-control study including pregnancies at term with detection of maternal intrapartum pyrexia, delivered between January 2020 and June 2021. Cardiotocography traces were entirely evaluated, since admission till delivery, and classified according to the International Federation of Obstetrics and Gynecology (FIGO) guideline. Maternal and neonatal outcomes were also recorded as secondary outcomes. Placentas have been studied according to the Amniotic Fluid Infection Nosology Committee. RESULTS: Forty four patients met the inclusion criteria and were included in the study cohort. There was a significant association between the use of oxytocin augmentation in labor and the histologic diagnosis of chorioamnionitis. A significative recurrence of loss and/or absence of accelerations at the point of pyrexia was also documented in women with histological chorioamnionitis compared to the others. CONCLUSIONS: Chorioamnionitis appears to be associated with myometrial disfunction, as suggested by the increased use of oxytocin augmentation during active labor of women at term with intrapartum pyrexia and histologic diagnosis of chorioamnionitis.

A putative design for the electromagnetic activation of split proteins for molecular and cellular manipulation.

The ability to manipulate cellular function using an external stimulus is a powerful strategy for studying complex biological phenomena. One approach to modulate the function of the cellular environment is split proteins. In this method, a biologically active protein or an enzyme is fragmented so that it reassembles only upon a specific stimulus. Although many tools are available to induce these systems, nature has provided other mechanisms to expand the split protein toolbox. Here, we show a novel method for reconstituting split proteins using magnetic stimulation. We found that the electromagnetic perceptive gene (EPG) changes conformation due to magnetic field stimulation. By fusing split fragments of a certain protein to both termini of the EPG, the fragments can be reassembled into a functional protein under magnetic stimulation due to conformational change. We show this effect with three separate split proteins: NanoLuc, APEX2, and herpes simplex virus type-1 thymidine kinase. Our results show, for the first time, that reconstitution of split proteins can be achieved only with magnetic fields. We anticipate that this study will be a starting point for future magnetically inducible split protein designs for cellular perturbation and manipulation. With this technology, we can help expand the toolbox of the split protein platform and allow better elucidation of complex biological systems.

Molecular Mechanisms Regulating GRF Activity in Plant Growth, Development, and Environmental Responses.

Plants rely on complex regulatory mechanisms to ensure proper growth and development. As sessile organisms, these mechanisms must be flexible enough to adapt to changes in the environment. The GROWTH-REGULATING FACTORs (GRFs) are plant-specific transcription factors that act as a central hub controlling plant growth and development, offering promising biotechnological applications to enhance plant performance. Here, we analyze the complex molecular mechanisms that regulate GRF activity, and how their natural and synthetic variants can impact on plant growth and development. We describe the biological roles of the GRFs and examine how they regulate gene expression and contribute to the control of organ growth and the plant's response to a changing environment. This review focuses on the premise that unlocking their full biotechnological potential requires a thorough understanding of the various regulatory layers governing GRF activity, the functional divergence among GRF family members and the gene networks that they regulate.

[Translated article] Comparative study of deep lipomas and atypical lipomatous tumours: Malignancy risk factors.

BACKGROUND AND OBJECTIVES: The diagnostic suspicion of an atypical lipomatous tumour (ALT) is difficult. The aim of this study is to delve into the most controversial diagnostic aspects of the subject. MATERIAL AND METHOD: Observational, longitudinal and retrospective study of a series of 96 deep adipose tumours (75 lipomas and 21 TLA) from 2006 to 2016: demographic, clinical, imaging and pathological variables were analysed and compared, as well as other variables related to treatment and oncological outcomes of the patients. A descriptive analysis of the collected variables was performed for the statistical study. To evaluate the potential predictor variables of malignancy, a multivariate logistic regression analysis was performed, including those that were statistically significant in the univariate analysis. RESULTS: Older age at diagnosis, lower limb location and larger size were significantly more frequent in ALTs. MRI findings showed no statistically significant differences between the two groups. In multivariate analysis, the same clinical variables were confirmed as predictors of malignancy. In the ROC curve, an optimal cut-off point of 134.0mm was used as a predictor of malignancy. CONCLUSIONS: Advanced age, location in the lower limbs and larger size are risk factors for malignancy in the differential diagnosis of deep lipomas and atypical lipomatous tumours. No radiological variable on MRI reached significance as a predictor of malignancy in our series.

Comparative study of deep lipomas and atypical lipomatous tumours: Malignancy risk factors. / Estudio comparativo de lipomas profundos y tumor lipomatoso atípico. Factores pronósticos de malignidad.

BACKGROUND AND OBJECTIVES: The diagnostic suspicion of an atypical lipomatous tumour (ALT) is difficult. The aim of this study is to delve into the most controversial diagnostic aspects of the subject. MATERIAL AND METHOD: Observational, longitudinal, and retrospective study of a series of 96 deep adipose tumours (75 lipomas and 21 TLA) from 2006 to 2016: demographic, clinical, imaging and pathological variables were analysed and compared, as well as other variables related to treatment and oncological outcomes of the patients. A descriptive analysis of the collected variables was performed for the statistical study. To evaluate the potential predictor variables of malignancy, a multivariate logistic regression analysis was performed, including those that were statistically significant in the univariate analysis. RESULTS: Older age at diagnosis, lower limb location and larger size were significantly more frequent in ALTs. MRI findings showed no statistically significant differences between the two groups. In multivariate analysis, the same clinical variables were confirmed as predictors of malignancy. In the ROC curve, an optimal cut-off point of 134.0 mm was used as a predictor of malignancy. CONCLUSIONS: Advanced age, location in the lower limbs and larger size are risk factors for malignancy in the differential diagnosis of deep lipomas and atypical lipomatous tumours. No radiological variable on MRI reached significance as a predictor of malignancy in our series.

Hepatocellular carcinoma in pregnancy: A systematic review.

INTRODUCTION: Hepatocellular carcinoma (HCC) is the most frequent primary malignant liver tumor and typically develops in the context of chronic liver disease, such as liver cirrhosis or chronic hepatitis B virus infection. Ultrasound evaluation, CT scan, and MRI are used to detect HCC. α-fetoprotein (AFP) is a common marker used to detect HCC in the non-pregnant population, which notoriously increases in pregnant women in relation to gestational age. Treatment is driven by the extent of the disease and the severity of underlying liver disease. Pregnancy may represent an obstacle to diagnosis and appropriate treatment of HCC. The aim of this descriptive systematic review was to describe the clinical features and maternal and neonatal outcomes of HCC in pregnancy. MATERIAL AND METHODS: We performed a systematic review of the literature about HCC diagnosed in pregnancy and the postpartum period, with signs or symptoms arising in pregnancy. We included case reports and case series describing the clinical features of women diagnosed with HCC, fibrolamellar variant of HCC, and mixed HCC and cholangiocarcinoma during pregnancy or the postpartum period (with onset of symptoms during pregnancy), from inception to March 2023. The study protocol was registered with the PROSPERO database (Registration number: ID CRD42021275584). RESULTS: We identified 180 records. The articles included in this systematic review were 47 case reports and 5 case series, for a total of 63 pregnancies. The two most frequent predisposing conditions were hepatitis B virus infection (30/63; 47%) and liver cirrhosis (14/63; 22%). Ultrasound evaluation was the most used technique to detect HCC. AFP was higher than normal in 28/46 patients tested (61%). Surgical treatment was the most used therapy, both during pregnancy and after delivery. Twenty-six patients (26/63; 42%) died within 6 months of diagnosis. Survival >24 months was 9% (4/46) in symptomatic and 29% (5/17) in asymptomatic women. No patient with cirrhotic liver survived more than 12 months. Thirty-eight newborns were alive at 28 days of age (38/63; 61%). CONCLUSIONS: Hepatocellular carcinoma in pregnancy is associated with a high risk of maternal and neonatal mortality. Diagnosis in asymptomatic high-risk women or following abnormal maternal serum AFP screening is associated with better maternal outcomes.

Evaluating the long term effectiveness of a Mediterranean marine protected area to tackle the effects of invasive and range expanding herbivorous fish on rocky reefs.

Here we provide evidence, along an 8-year period time-series based on multifaceted data from a Mediterranean marine protected area (MPA), whether protection can tackle invasive and range expanding herbivore fishes, and their effects on the algal resource availability, taking into account the population trends of predatory fishes, fisheries catches of herbivore fishes and sea surface temperature (SST) through time. Our findings pointed out that an ineffective in restoring top-down control process MPA may facilitate, rather than alleviate, the sudden and enduring population burst of invasive and range-expanding herbivorous fishes at tipping points of abrupt change. This subsequently results in the deterioration of rocky reef habitats and the depletion of algal resources, with the tipping points of abrupt change for algal and herbivore fish species not overlapping chronologically. As sea temperature increases, ineffective or recently established MPAs may inadvertently facilitate the proliferation of invasive and range-expanding species, posing a significant challenge to management effectiveness and conservation objectives.

A strange case of pleuritic pain in the third trimester of pregnancy.

Pulmonary sequestration is an uncommon congenital malformation of the lung, generally diagnosed in childhood or adolescence, corresponding to dysplastic lung tissue not communicating with the rest of vascular or bronchial lung system but receiving an arterial blood supply from systemic arteries. Currently, surgical resection is usually indicated in order to prevent or treat related symptoms or complications, although controversy exists regarding its use in asymptomatic patients and adults. We present the case of a 32-year-old pregnant woman with acute chest pain and vomiting diagnosed with intralobar sequestration at 32+2 weeks of gestation and treated with pulmonary lobectomy after giving birth by cesarean section at 33+0 weeks of gestation.

Bioluminescent Genetically Encoded Glutamate Indicators for Molecular Imaging of Neuronal Activity.

Genetically encoded optical sensors and advancements in microscopy instrumentation and techniques have revolutionized the scientific toolbox available for probing complex biological processes such as release of specific neurotransmitters. Most genetically encoded optical sensors currently used are based on fluorescence and have been highly successful tools for single-cell imaging in superficial brain regions. However, there remains a need to develop new tools for reporting neuronal activity in vivo within deeper structures without the need for hardware such as lenses or fibers to be implanted within the brain. Our approach to this problem is to replace the fluorescent elements of the existing biosensors with bioluminescent elements. This eliminates the need of external light sources to illuminate the sensor, thus allowing deeper brain regions to be imaged noninvasively. Here, we report the development of the first genetically encoded neurotransmitter indicators based on bioluminescent light emission. These probes were optimized by high-throughput screening of linker libraries. The selected probes exhibit robust changes in light output in response to the extracellular presence of the excitatory neurotransmitter glutamate. We expect this new approach to neurotransmitter indicator design to enable the engineering of specific bioluminescent probes for multiple additional neurotransmitters in the future, ultimately allowing neuroscientists to monitor activity associated with a specific neurotransmitter as it relates to behavior in a variety of neuronal and psychiatric disorders, among many other applications.

Bundles reduce anastomosis leak in patients undergoing elective colorectal surgery. A propensity score-matched study.

Background: anastomosis leak still being a handicap in colorectal surgery. Bowel mechanical preparation and oral antibiotics are not a practice recommended in many clinical practice guides. The aim is to analyse the decrease in frequency and severity of postoperative complications, mainly related to anastomotic leak, after the establishment of a bundle. Methods: Single-center, before-after study. A bundle was implemented to reduce anastomotic leaks and their consequences. The Bundle group were matched to Pre-bundle group by propensity score matching. Mechanical bowel preparation, oral and intravenous antibiotics, inflammatory markers measure and early diagnosis algorithm were included at the bundle. Results: The bundle group shown fewer complications, especially in Clavien Dindós Grade IV complications (2.3% vs. 6.2% p < 0.01), as well as a lower rate of anastomotic leakage (15.5% vs. 2.2% p < 0.01). A significant decrease in reinterventions, less intensive unit care admissions, a shorter hospital stay and fewer readmissions were also observed. In multivariate analysis, the application of a bundle was an anastomotic leakage protective factor (OR 0.121, p > 0.05). Conclusions: The implementation of our bundle in colorectal surgery which include oral antibiotics, mechanical bowel preparation and inflammatory markers, significantly reduces morbidity adjusted to severity of complications, the anastomotic leakage rate, hospital stay and readmissions. Register study: The study has been registered at clinicaltrials.gov Code: nct04632446.

Fossil berries reveal global radiation of the nightshade family by the early Cenozoic.

Fossil discoveries can transform our understanding of plant diversification over time and space. Recently described fossils in many plant families have pushed their known records farther back in time, pointing to alternative scenarios for their origin and spread. Here, we describe two new Eocene fossil berries of the nightshade family (Solanaceae) from the Esmeraldas Formation in Colombia and the Green River Formation in Colorado (USA). The placement of the fossils was assessed using clustering and parsimony analyses based on 10 discrete and five continuous characters, which were also scored in 291 extant taxa. The Colombian fossil grouped with members of the tomatillo subtribe, and the Coloradan fossil aligned with the chili pepper tribe. Along with two previously reported early Eocene fossils from the tomatillo genus, these findings indicate that Solanaceae were distributed at least from southern South America to northwestern North America by the early Eocene. Together with two other recently discovered Eocene berries, these fossils demonstrate that the diverse berry clade and, in turn, the entire nightshade family, is much older and was much more widespread in the past than previously thought.

Síndrome antifosfolípido y tumores cardiacos

Presentamos el caso de una paciente mujer de 31 años con antecedente de litiasis coraliforme bilateral. Ella inició la enfermedad un mes antes del ingreso con trombocitopenia y anemia hemolítica autoinmune. Fue diagnosticada con Síndrome de Evans, inicialmente tuvo marcadores de autoinmunidad negativos, finalmente presentó disnea progresiva y se le encontró 4 masas intracardiacas en aurícula derecha y marcadores positivos para síndrome antifosfolípido. A pesar de la anticoagulación y preparación para cirugía cardiaca, la paciente tuvo una muerte súbita.

We present the case of a 31-year-old female patient with a history of bilateral staghorn lithiasis, who started the disease one month before admission with thrombocytopenia and autoimmune hemolytic anemia. She was diagnosed with Evans Syndrome, initially she had negative autoimmunity markers, finally presented progressive dyspnea and 4 intracardiac masses were found in the right atrium and positive markers for antiphospholipid syndrome. Despite anticoagulation and preparation for cardiac surgery, she presented sudden death.

Assigning Viscosity Values in the Glass Softening Temperature Range.

A new optical method for assigning glass viscosity values in the softening temperature range is presented. In this method, an irregular particle, a few millimeters in size, laying on an alumina plate, is heated up to temperature T, and then remains at this temperature. T should be within the softening temperature range of the glass. There are no external applied shear stresses, the only acting shear forces are those coming from the particle's own surface energy. At the fixed temperature T, the surface free energy of the sample decreases by viscous flow while its shape evolves from a polyhedron or irregular shape towards a spherical or rounded shape. This shape evolution is recorded using a photographic camera. From each image, the sample's roundness is determined, obtaining a characteristic time τ from the roundness against time. Simultaneously, using the available software, a value for the viscosity η was calculated, at temperature T, allowing for building sets of T, τ, η, namely three data values. Accordingly, if T, τ are considered as independent variables, a master function η = η (T, τ) can be built. Now, if we measure T, τ data on a glass of an unknown viscosity, the master function makes it possible to assign a η value. When incipient crystallization or liquid-liquid phase separations are present, effective viscosity values are obtained. This method requires a high temperature microscope, as well as tridimmensional samples with a few cubic millimeters of volume. Each isothermal τ determination can take from minutes to several hours. We tested the method with two glasses of known viscosity values: borosilicate glass (VG98) and alumimoborosilicate glass (SG7), both of which are used for radioactive waste immobilization and have assigned log(η) values between 6 and 7.3 with η in Pa s. The discrepancy between the log(η) values assigned here and those values fitted with a VFT function on the values measured for the SG7 and VG98 glasses were within ±14%.

Post-COVID-19 tomographic abnormalities.

BACKGROUND: The prevalence of persistent respiratory symptoms tends to be low in patients with a longer recovery time after COVID-19. However, some patients may present persistent pulmonary abnormalities.OBJECTIVE: To evaluate the prevalence of tomographic abnormalities 90 days after symptom onset in patients with COVID-19 and compare two chest high-resolution computed tomography (HRCT) analysis techniques.METHODS: A multicentre study of patients hospitalised with COVID-19 having oxygen saturation <93% on room air at hospital admission were evaluated using pulmonary function and HRCT scans 90 days after symptom onset. The images were evaluated by two thoracic radiologists, and were assessed using software that automatically quantified the extent of pulmonary abnormalities.RESULTS: Of the 91 patients included, 81% had at least one pulmonary lobe with abnormalities 90 days after discharge (84% were identified using the automated algorithm). Ground-glass opacities (76%) and parenchymal bands (65%) were the predominant abnormalities. Both chest HRCT technical assessments presented high sensitivity (95.9%) and positive predictive value (92%), with a statistically significant correlation at baseline (R = 0.80) and after 90 days (R = 0.36).CONCLUSION: The prevalence of pulmonary abnormalities on chest HRCT 90 days after symptom onset due to COVID-19 was high; both technical assessments can be used to analyse the images.

Chorionicity, birth weight discordance and neonatal morbidity in uncomplicated twin pregnancies delivered from 36 weeks.

OBJECTIVES: To investigate the association between chorionicity, birth weight discordance and neonatal morbidity in uncomplicated twin pregnancies progressing to at least 36 weeks of gestation. STUDY DESIGN: This was a retrospective single centre cohort study of all twin pregnancies referred to our twin clinic between 2011 and 2018. Outcome details were obtained from the computerized maternity and neonatal records. The primary outcome was incidence of composite neonatal morbidity according to chorionicity. We also determined the incidence of composite neonatal morbidity in pregnancies with birth weight discordance. Logistic regression was used to identify and adjust for potential confounders. RESULTS: Three hundred and eighty-five twin pregnancies (286 dichorionic, 99 monochorionic) were included. Gestational age at birth was significantly lower in pregnancies complicated by neonatal morbidity (p = 0.013) compared with those which were not. On multivariable logistic regression analysis, gestational age at birth (p = 0.031) and birth weight discordance (p = 0.004), but not chorionicity (p = 0.626) were independently associated with neonatal morbidity. CONCLUSION(S): In uncomplicated twin pregnancies chorionicity is not associated with neonatal morbidity. Gestational age at birth is the major determinant of neonatal outcome while the clinical impact of weight discordance seems marginally significant.

Risk Assessment in Solitary Fibrous Tumor of the Uterine Corpus: Report of a Case and Systematic Review of the Literature.

Solitary fibrous tumor (SFT) is an uncommon fibroblastic tumor occurring preferentially in the pleura, with a variable clinical course. SFT can arise also in numerous extrathoracic sites and very rarely in the female genital tract, with only scarce reports of uterine SFT. We reported a new uterine SFT arising in a 45-year-old woman, and we performed a systematic review of SFT cases of the uterine corpus interrogating the electronic databases PubMed, Web of Science, and Scopus. We identified only 13 patients diagnosed with SFT of the uterine corpus, including our one. Complete clinical workout at disease presentation showed no evidence of extrauterine spread in all cases, except for 1 patient who presented with metastatic disease. Tumor recurrences/metastases occurred in a minority of the patients and were poorly related to clinicopathological risk factors and patients stratification based on different scoring systems. Since the long-term clinical behavior of uterine SFT is limited and poorly predictable, extended follow-up is recommended also for all cases arising in the uterine corpus.

Ultrasound and magnetic resonance imaging in the diagnosis of clinically significant placenta accreta spectrum disorders.

OBJECTIVES: We aimed to assess the performance of ultrasound (US) and magnetic resonance imaging (MRI) signs for antenatal detection of placenta accreta spectrum (PAS) disorders in women with placenta previa (placental edge ≤2 cm from the internal uterine orifice, ≥260/7 weeks' gestation) with and without a history of previous Caesarean section. METHODS: Single center prospective observational study. US suspicion of PAS was raised in the presence of obliteration of the hypoechoic space between uterus and placenta, interruption of the hyperechoic uterine-bladder interface and/or turbulent placental lacunae on color Doppler. All MRI studies were blindly evaluated by a single operator. PAS was defined as clinically significant when histopathological diagnosis was associated with at least one of: intrauterine balloon placement, compressive uterine sutures, peripartum hysterectomy, uterine or hypogastric artery ligature, uterine artery embolization. RESULTS: A total of 39 women were included: 7/39 had clinically significant PAS. There were 6/18 cases of PAS with anterior placenta: hypoechoic space interruption and placental lacunae were the most sensitive sonographic signs (83%), while abnormal hyperechoic interface was the most specific (83%). On MRI, focal myometrial interruption and T2 intraplacental dark bands showed the best sensitivity (83%), bladder tenting had the best specificity (100%). 1/21 women with posterior placenta had PAS. There was substantial agreement between US and MRI in patients with anterior placenta (κ=0.78). CONCLUSIONS: US and MRI agreement in antenatal diagnosis of clinically significant PAS was maximal in high-risk women. Placental lacunae on ultrasound scan and T2 intraplacental hypointense bands on MRI should trigger the suspicion of PAS.

[Quadrivalent conjugate vaccines against ACWY meningococcal disease]. / I vaccini coniugati quadrivalenti contro i meningococchi ACWY.

Invasive meningococcal disease (IMD) is caused by 6 serogroups of the bacterium Neisseria meningitidis (A, B, C, W, X and Y). It is among the most serious vaccine preventable infectious diseases, characterized by a high case-fatality rate and risk of permanent sequelae. Worldwide, the incidence of IMD is generally low with differences among regions and age groups. The risk increases in overcrowded conditions or in case of travel to endemic areas. The first vaccines produced using polysaccharide capsular antigens have demonstrated a good protective efficacy, but of short lenght. The conjugation of antigens with proteins allowed to obtain a longlasting antibody response towards 4 serogroups: A, C, W, Y. Currently four ACWY quadrivalent conjugate vaccines are available, three of them approved in Europe, which have shown high immunogenicity and safety. In 2020 the MenACYW-TT vaccine conjugated to tetanus toxoid was approved in the USA and it is presently authorized in Europe for the immunization of individuals from 12 months of age. Clinical studies have demonstrated immunogenicity and safety on population samples belonging to different age groups and non-inferiority in comparing it with other vaccines already in use. The possibility of having an increasing number of safe, immunogenic and effective vaccines against IMD allows us to imagine a future without invasive meningococcal disease. It is therefore important to extend vaccination to an increasing number of subjects of different age groups and risk conditions.

[Posterior reversible encephalopathy syndrome in transplanted patients. Clinical features and imaging follow up]. / Leucoencefalopatía posterior reversible en pacientes trasplantados. Presentación clínica, radiológica y evolución.

Posterior reversible encephalopathy syndrome (PRES) is an acute neurological disorder characterized by headache, encephalopathy, seizures and visual disturbances, with reversible vasogenic edema in posterior brain areas. The aim of this research was to describe a case series of transplanted patients who developed PRES, characterize their presentation, treatment, clinical and imaging evolution. Electronic medical records were analyzed from January 2009 to January 2019. Demographic data, clinical backgrounds, causes of admission, hospital length of stay and time from transplantation to PRES were collected. Image improvement/resolution and annual survival were assessed. We identified 27 patients with PRES; 22 of 1647 total solid-organ transplant (1.3%) and 5 of 617 total bone marrow transplant (0.8%). The mean age at presentation was 38.2 years (SD 19.5), 62.9% female, 59.2% (16) before the year of transplantation. The most common comorbidities were kidney disease (14; 51%) and high blood pressure (11; 40%). Computed axial tomography (CT) was performed in 23 patients (85.1%), with pathological findings in 11 (47.8%). Magnetic resonance imaging (MRI) of 25 (92.6%), showed a characteristic pattern in 17 (62.9%) with improvement/resolution before the year in 20 (74%). Treatment was symptomatic, modifying immunosuppression. Five deaths were recorded during hospital stay and another 3 before the year of admission, with an annual survival of 70.3% (19 patients). Organ transplant trend is growing in our region. These patients are particularly susceptible to PRES, with a different imaging presentation and comorbidities from other populations.

El síndrome de leucoencefalopatía posterior reversible (PRES) es un desorden neurológico agudo caracterizado por cefalea, alteración de la conciencia, convulsiones y alteraciones visuales, con imágenes de edema vasogénico reversible en regiones cerebrales posteriores. Nos propusimos describir una serie de casos de pacientes trasplantados que desarrollaron PRES, caracterizando su presentación, evolución clínica, imágenes y terapéutica. Se analizaron historias clínicas informatizadas desde enero 2009 hasta enero 2019. Se recabaron datos demográficos, antecedentes clínicos, motivos y días de internación, tiempos desde el trasplante a la presentación clínica y diagnóstico. Se evaluó la mejoría/resolución en estudios por imágenes y la supervivencia anual. Se identificaron 27 pacientes con PRES; 22 trasplantados de órgano sólido de 1647 totales (1.3%) y 5 de médula ósea de 617 totales (0.8%). La media de edad fue de 38.2 años (DS 19.5), 62.9% de sexo femenino, 59.2% (16) antes del año del trasplante. Las comorbilidades más frecuentes enfermedad renal (14; 51%) e hipertensión arterial (11; 40%). Se realizó tomografía axial computarizada (TAC) a 23 pacientes (85.1%), siendo patológica en 11 (47.8%), y resonancia magnética nuclear (RMN) a 25 (92.6%), mostrando patrón característico en 17 (62.9%), con mejoría/resolución antes del año en 20 (74%). El tratamiento fue sintomático, modificando la inmunosupresión. Se registraron 5 óbitos durante la internación y otros 3 antes del año, con una supervivencia anual del 70.3% (19). La población de trasplantados, en crecimiento en nuestro medio, es particularmente susceptible al PRES. Tanto su presentación en estudios por imágenes, como su comorbilidad, difieren de otras poblaciones.