Time Course of Mechanical Ventilation Driving Pressure Levels in Pediatric Acute Respiratory Distress Syndrome: Outcomes in a Prospective, Multicenter Cohort Study From Colombia, 2018-2022.

OBJECTIVES: High driving pressure (DP, ratio of tidal volume (Vt) over respiratory system compliance) is a risk for poor outcomes in patients with pediatric acute respiratory distress syndrome (PARDS). We therefore assessed the time course in level of DP (i.e., 24, 48, and 72 hr) after starting mechanical ventilation (MV), and its association with 28-day mortality. DESIGN: Multicenter, prospective study conducted between February 2018 and December 2022. SETTING: Twelve tertiary care PICUs in Colombia. PATIENTS: One hundred eighty-four intubated children with moderate to severe PARDS. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The median (interquartile range [IQR]) age of the PARDS cohort was 11 (IQR 3-24) months. A total of 129 of 184 patients (70.2%) had a pulmonary etiology leading to PARDS, and 31 of 184 patients (16.8%) died. In the first 24 hours after admission, the plateau pressure in the nonsurvivor group, compared with the survivor group, differed (28.24 [IQR 24.14-32.11] vs. 23.18 [IQR 20.72-27.13] cm H2O, p < 0.01). Of note, children with a Vt less than 8 mL/kg of ideal body weight had lower adjusted odds ratio (aOR [95% CI]) of 28-day mortality (aOR 0.69, [95% CI, 0.55-0.87]; p = 0.02). However, we failed to identify an association between DP level and the oxygenation index (aOR 0.58; 95% CI, 0.21-1.58) at each of time point. In a diagnostic exploratory analysis, we found that DP greater than 15 cm H2O at 72 hours was an explanatory variable for mortality, with area under the receiver operating characteristic curve of 0.83 (95% CI, 0.74-0.89); there was also increased hazard for death with hazard ratio 2.5 (95% CI, 1.07-5.92). DP greater than 15 cm H2O at 72 hours was also associated with longer duration of MV (10 [IQR 7-14] vs. 7 [IQR 5-10] d; p = 0.02). CONCLUSIONS: In children with moderate to severe PARDS, a DP greater than 15 cm H2O at 72 hours after the initiation of MV is associated with greater odds of 28-day mortality and a longer duration of MV. DP should be considered a variable worth monitoring during protective ventilation for PARDS.

Metal adduction in mass spectrometric analyses of carbohydrates and glycoconjugates.

Glycans, carbohydrates, and glycoconjugates are involved in many crucial biological processes, such as disease development, immune responses, and cell-cell recognition. Glycans and carbohydrates are known for the large number of isomeric features associated with their structures, making analysis challenging compared with other biomolecules. Mass spectrometry has become the primary method of structural characterization for carbohydrates, glycans, and glycoconjugates. Metal adduction is especially important for the mass spectrometric analysis of carbohydrates and glycans. Metal-ion adduction to carbohydrates and glycoconjugates affects ion formation and the three-dimensional, gas-phase structures. Herein, we discuss how metal-ion adduction impacts ionization, ion mobility, ion activation and dissociation, and hydrogen/deuterium exchange for carbohydrates and glycoconjugates. We also compare the use of different metals for these various techniques and highlight the value in using metals as charge carriers for these analyses. Finally, we provide recommendations for selecting a metal for analysis of carbohydrate adducts and describe areas for continued research.

Differences in SARS-CoV-2 Clinical Manifestations and Disease Severity in Children and Adolescents by Infecting Variant.

Since the COVID-19 pandemic began, different SARS-CoV-2 variants have been identified and associated with higher transmissibility than the ancestral nonvariant strain. During January 1, 2021-January 15, 2022, we assessed differences in clinical and viral parameters in a convenience sample of COVID-19 outpatients and inpatients 0-21 years of age in Columbus, Ohio, USA, according to the infecting variant, identified using a mutation-specific reverse transcription PCR assay. Of the 676 patients in the study, 17.75% were infected with nonvariant strains, 18.49% with the Alpha variant, 41.72% with Delta, and 16.42% with Omicron. Rates of SARS-COV-2/viral co-infections were 15.66%-29.41% and were comparable across infecting variants. Inpatients with acute Delta and Omicron infections had lower SARS-CoV-2 cycle threshold values and more frequent fever and respiratory symptoms than those with nonvariant strain infections. In addition, SARS-COV-2/viral co-infections and the presence of underlying conditions were independently associated with worse clinical outcomes, irrespective of the infecting variant.

Renal length z-score for the detection of dysfunction in children with solitary functioning kidney.

AIM: To evaluate whether renal length z-scores predict renal dysfunction in children with a solitary functioning kidney (SFK). METHODS: In a single-centre retrospective cohort of children with SFK, we correlated body mass index z-scores, extracellular volume and lean body mass to renal length z-scores. We grouped these z-scores to other markers of renal dysfunction (proteinuria, hypertension, extracellular volume and abnormal estimated glomerular function rate [eGFR]) and analysed renal length z-score with multivariate analysis, receiver-operated characteristics (ROC) plots and Youden's index to determine an appropriate cut-off. RESULTS: 111 children had a median follow-up 5.08 years, eGFR 80.8 mL/min/1.73 m2 , and age at last follow-up 7.4 (3.8-13.4 years). The median renal length z-scores of those without any renal dysfunction (n = 37, 25.1%) were greater (+3.66, interquartile range 3.02-4.47) than those with renal dysfunction (median 3.11, interquartile range 1.76-4.11, P = .0107, Mann-Whitney test). Using a cut-off of z-score of >+1.911, the odds ratio for having no renal dysfunction was 0.07 (95% CI 0.002-0.459, P = .0010). However, accuracy of the renal length z-score was poor (ROC curve 0.6488). CONCLUSION: In this cohort of children with SKF, using the renal length z-score as a biomarker of renal dysfunction at 7 years of age is not recommended.

Adenosine monophosphate-activated protein kinase activation protects against sepsis-induced organ injury and inflammation.

BACKGROUND: Mortality in sepsis is most often attributed to the development of multiple organ failure. In sepsis, inflammation-mediated endothelial activation, defined as a proinflammatory and procoagulant state of the endothelial cells, has been associated with severity of disease. Thus, the objective of this study was to test the hypothesis that adenosine monophosphate-activated protein kinase (AMPK) activation limits inflammation and endothelium activation to protect against organ injury in sepsis. 5-aminoimidazole-4-carboxamide ribonucleotide (AICAR), which is an adenosine monophosphate analog, has been used to upregulate activity of AMPK. Compound C is a cell-permeable pyrrazolopyrimidine compound that inhibits AMPK activity. METHODS: Wild-type mice underwent cecal ligation and puncture (CLP) or sham surgery. Mice were randomized to vehicle, AICAR, or compound C. Mouse kidney endothelial cells were used for in vitro experiments. Renal and liver function were determined by serum cystatin C, blood urea nitrogen (BUN), creatinine, and alanine aminotransferase. Serum cytokines were measured by enzyme-linked immunosorbent assay. Microvascular injury was determined using Evans blue dye and electron microscopy. Immunohistochemistry was used to measure protein levels of phospho-AMPK (p-AMPK), microtubule-associated protein 1A/1B-light chain 3 (LC3), and intracellular adhesion molecule. LC3 levels were used as a measure of autophagosome formation. RESULTS: AICAR decreased liver and kidney injury induced by CLP and minimized cytokine elevation in vivo and in vitro. CLP increased renal and hepatic phosphorylation of AMPK and autophagic signaling as determined by LC3. Inhibition of AMPK with compound C prevented CLP-induced autophagy and exacerbated tissue injury. Additionally, CLP led to endothelial injury as determined by electron microscopy and Evans blue dye extravasation, and AICAR limited this injury. Furthermore, AICAR limited CLP and lipopolysaccharide (LPS)-induced upregulation of intracellular adhesion molecule in vivo and in vitro and decreased LPS-induced neutrophil adhesion in vitro. CONCLUSIONS: In this model, activation of AMPK was protective, and AICAR minimized organ injury by decreasing inflammatory cytokines and endothelial activation. These data suggest that AMPK signaling influences sepsis or LPS-induced endothelial activation and organ injury.

Effects of inhalation of low-dose nitrite or carbon monoxide on post-reperfusion mitochondrial function and tissue injury in hemorrhagic shock swine.

INTRODUCTION: Tissue reperfusion following hemorrhagic shock may paradoxically cause tissue injury and organ dysfunction by mitochondrial free radical expression. Both nitrite and carbon monoxide (CO) may protect from this reperfusion injury by limiting mitochondrial free radial production. We explored the effects of very small doses of inhaled nitrite and CO on tissue injury in a porcine model of hemorrhagic shock. METHODS: Twenty pigs (mean wt. 30.6 kg, range 27.2 to 36.4 kg) had microdialysis catheters inserted in muscle, peritoneum, and liver to measure lactate, pyruvate, glucose, glycerol, and nitrite. Nineteen of the pigs were bled at a rate of 20 ml/min to a mean arterial pressure of 30 mmHg and kept between 30 and 40 mmHg for 90 minutes and then resuscitated. One pig was instrumented but not bled (sham). Hemorrhaged animals were randomized to inhale nothing (control, n = 7), 11 mg nitrite (nitrite, n = 7) or 250 ppm CO (CO, n = 5) over 30 minutes before fluid resuscitation. Mitochondrial respiratory control ratio was measured in muscle biopsies. Repeated measures from microdialysis catheters were analyzed in a random effects mixed model. RESULTS: Neither nitrite nor CO had any effects on the measured hemodynamic variables. Following inhalation of nitrite, plasma, but not tissue, nitrite increased. Following reperfusion, plasma nitrite only increased in the control and CO groups. Thereafter, nitrite decreased only in the nitrite group. Inhalation of nitrite was associated with decreases in blood lactate, whereas both nitrite and CO were associated with decreases in glycerol release into peritoneal fluid. Following resuscitation, the muscular mitochondrial respiratory control ratio was reduced in the control group but preserved in the nitrite and CO groups. CONCLUSIONS: We conclude that small doses of nebulized sodium nitrite or inhaled CO may be associated with intestinal protection during resuscitation from severe hemorrhagic shock.

Management of hidradenitis suppurativa with biological therapy: report of four cases and review of the literature.

Several studies report the usefulness of different biological therapies in the management of a difficult-to-treat pathology such as hidradenitis suppurativa (HS). However, there are little data on this, which shows the great difficulty in the management of this disease. We will report herein our experience of the treatment of four complex cases of HS. We will also review previous cases published in the literature in order to further assess the results obtained with different biological drugs in terms of efficacy and safety. We conclude that, in the near future, biological therapy could become an essential tool in the management of cases of HS who have not previously responded to classical treatment.

Emerging Resistance Trends in Viridans Group Streptococci Bloodstream Infections Among Immunocompromised Children Receiving Levofloxacin Prophylaxis.

BACKGROUND: Levofloxacin prophylaxis (LVXp) is often used for patients with underlying leukemia and severe neutropenia to reduce the risk of fever and bacteremia. This study evaluated trends in viridans group streptococci (VGS) antibiotic susceptibilities over time and clinical outcomes of children with VGS bloodstream infections (BSIs) during institutional adoption of LVXp. METHODS: VGS blood culture isolates between 1/1/2010 and 12/31/2021 with susceptibility testing reported were included. Available isolates were re-identified to the species level and additional susceptibility testing was performed. Demographic and clinical data were abstracted from medical records. RESULTS: A total of 264 VGS BSI isolates were identified in immunocompromised (IC, n = 125) and non-immunocompromised subjects, (non-IC, n = 139). IC subjects had lower rates of VGS isolates susceptible (S) to LVX and higher minimum inhibitory concentration (MICs) to LVX (p = 0.004) and ciprofloxacin (p = 0.0005) compared with non-IC subjects. No other evaluated antibiotic had increased MICs in either group. Fifteen of 19 (74%) LVX not susceptible (NS) isolates occurred in IC subjects, 13 represented breakthrough infections. IC subjects had higher rates of VGS-related shock (p = 0.012), need for pressor support (p = 0.039), and longer duration of hospitalization than non-IC subjects (p < 0.001). Clinical outcomes were comparable between subjects with LVX S and NS VGS BSI isolates. CONCLUSIONS: VGS with reduced susceptibility to LVX emerged during institutional adoption of LVXp in high-risk children with immunocompromising conditions, but did not result in significant differences in clinical outcomes. Ongoing surveillance and susceptibility testing are critical in weighing the utility of LVXp against emerging antimicrobial resistance in this high-risk population.

Use of multiplex PCR in pleural effusion: is it necessary to change the paradigm of culture-based methods?

The microbiological diagnosis of pleural effusion is based largely on classical microbiology methods, but these methods have a high rate of false negative results. Some previous studies have shown improved diagnostic performance for pathogens such as Streptococcus pneumoniae using molecular biology methods. We present the use of a multiplex PCR platform (BIOFIRE FILMARRAY Pneumonia Panel) for the aetiological diagnosis of pleural effusion in paediatric pneumonia. We present a case series of 17 pleural fluid samples that were processed by culture-based microbiology and molecular biology methods. Microbiological isolation was successful in four cases (25 %) through traditional culture methods. In contrast, the molecular biology panels allowed for detection in 16 out of 17 cases (94 %). The results from these panels led to a change in management for nine out of the 17 cases (52 %). This study found an increase in aetiological diagnosis in complicated pneumonia in children by using molecular biology methods, which led to a significant change in patient management.

[Depression and its relationship with mild cognitive impairment and Alzheimer disease: A review study]. / La depresión y su relación con el deterioro cognitivo leve y la enfermedad de Alzheimer. Un estudio de revisión sistemática.

The objective of the present study was to determine whether depression precedes Mild cognitive impairment (MCI) as a risk factor or as a predictor in Alzheimer's disease (AD). A systematic review of observational studies (cross-sectional and cohort or follow-up) was carried out using the PRISMA search algorithm, for clinical markers in MCI and AD, in the Science Direct, Springer, Scopus and Proquest databases. The study eligibility criteria included inclusion criteria: of types of documents, articles of primary studies, type of source scientific journals, published in the English language, from January 2010 to April 2020, in patients with MCI and AD and in the group of age included in people with a minimum age range of 45years. Exclusion criteria were: publications older than 10years because the aim of the article was to explore recent studies, secondary research studies, type of report document, languages other than English. 3385 articles were identified, of which 30 articles were finally selected. It was found that there is an association between depression and AD, but properly as a risk factor but not, as a predictor or clinical marker of the development of AD. The degree of association is greater when they present depressive symptoms and simultaneously report subjective memory complaints or the presence of MCI.

Myeloid-Derived Suppressor Cells and Clinical Outcomes in Children With COVID-19.

Background: Although children with COVID-19 account for fewer hospitalizations than adults, many develop severe disease requiring intensive care treatment. Critical illness due to COVID-19 has been associated with lymphopenia and functional immune suppression. Myeloid-derived suppressor cells (MDSCs) potently suppress T cells and are significantly increased in adults with severe COVID-19. The role of MDSCs in the immune response of children with COVID-19 is unknown. Aims: We hypothesized that children with severe COVID-19 will have expansion of MDSC populations compared to those with milder disease, and that higher proportions of MDSCs will correlate with clinical outcomes. Methods: We conducted a prospective, observational study on a convenience sample of children hospitalized with PCR-confirmed COVID-19 and pre-pandemic, uninfected healthy controls (HC). Blood samples were obtained within 48 h of admission and analyzed for MDSCs, T cells, and natural killer (NK) cells by flow cytometry. Demographic information and clinical outcomes were obtained from the electronic medical record and a dedicated survey built for this study. Results: Fifty children admitted to the hospital were enrolled; 28 diagnosed with symptomatic COVID-19 (10 requiring ICU admission) and 22 detected by universal screening (6 requiring ICU admission). We found that children with severe COVID-19 had a significantly higher percentage of MDSCs than those admitted to the ward and uninfected healthy controls. Increased percentages of MDSCs in peripheral blood mononuclear cells (PBMC) were associated with CD4+ T cell lymphopenia. MDSC expansion was associated with longer hospitalizations and need for respiratory support in children admitted with acute COVID-19. Conclusion: These findings suggest that MDSCs are part of the dysregulated immune responses observed in children with severe COVID-19 and may play a role in disease pathogenesis. Future mechanistic studies are required to further understand the function of MDSCs in the setting of SARS-CoV-2 infection in children.

Corrigendum to: 204. Mucosal Cytokine Profiles in Children with COVID-19.

[This corrects the article DOI: 10.1093/ofid/ofab466.000.].

Nonoccupational Allergic Contact Dermatitis to 4-Acryloylmorpholine in Smartwatch Screen Protectors Glue.

BACKGROUND: We recently identified an outbreak of occupational allergic contact dermatitis (ACD) involving workers of a Spanish company selling smartphone protective cases from a glue product. A chemical analysis of one glue sample revealed the presence of 4-acryloylmorpholine among other allergens.The same glue is also used to attach tempered glass protective cases to Apple smartwatches. OBJECTIVE: Our objective was to describe a case series of nonoccupational consumer ACD from the previously mentioned Apple smartwatch protective case glue. METHODS: We evaluated epidemiological and clinical data, as well as patch tests results. RESULTS: Three women were diagnosed with nonoccupational ACD from the adhesive. An annular vesicular inflammatory plaque involving the dorsal aspect of the wrist was initially observed in all. Two of the 3 patients were patch tested with 4-acryloylmorpholine 0.5% with positive strong reactions. Both also strongly reacted to a sample of the glue semiopen tested in a drop of petrolatum. One of them was also positive for various acrylates. CONCLUSIONS: 4-Acryloylmorpholine has been identified in an adhesive used to attach protective cases to smartwatches. Nonoccupational ACD have been described to involve consumers of smartwatches. A UV-curable adhesive used to attach protective cases to smartwatches has been considered to be the culprit.

Association of Cancer Diagnosis and Therapeutic Stage With Mortality in Pediatric Patients With COVID-19, Prospective Multicenter Cohort Study From Latin America.

Background: Children with cancer are at risk of critical disease and mortality from COVID-19 infection. In this study, we describe the clinical characteristics of pediatric patients with cancer and COVID-19 from multiple Latin American centers and risk factors associated with mortality in this population. Methods: This study is a multicenter, prospective cohort study conducted at 12 hospitals from 6 Latin American countries (Argentina, Bolivia, Colombia, Ecuador, Honduras and Peru) from April to November 2021. Patients younger than 14 years of age that had an oncological diagnosis and COVID-19 or multisystemic inflammatory syndrome in children (MIS-C) who were treated in the inpatient setting were included. The primary exposure was the diagnosis and treatment status, and the primary outcome was mortality. We defined "new diagnosis" as patients with no previous diagnosis of cancer, "established diagnosis" as patients with cancer and ongoing treatment and "relapse" as patients with cancer and ongoing treatment that had a prior cancer-free period. A frequentist analysis was performed including a multivariate logistic regression for mortality. Results: Two hundred and ten patients were included in the study; 30 (14%) died during the study period and 67% of patients who died were admitted to critical care. Demographics were similar in survivors and non-survivors. Patients with low weight for age (<-2SD) had higher mortality (28 vs. 3%, p = 0.019). There was statistically significant difference of mortality between patients with new diagnosis (36.7%), established diagnosis (1.4%) and relapse (60%), (p <0.001). Most patients had hematological cancers (69%) and they had higher mortality (18%) compared to solid tumors (6%, p= 0.032). Patients with concomitant bacterial infections had higher mortality (40%, p = 0.001). MIS-C, respiratory distress, cardiovascular symptoms, altered mental status and acute kidney injury on admission were associated with higher mortality. Acidosis, hypoxemia, lymphocytosis, severe neutropenia, anemia and thrombocytopenia on admission were also associated with mortality. A multivariate logistic regression showed risk factors associated with mortality: concomitant bacterial infection OR 3 95%CI (1.1-8.5), respiratory symptoms OR 5.7 95%CI (1.7-19.4), cardiovascular OR 5.2 95%CI (1.2-14.2), new cancer diagnosis OR 12 95%CI (1.3-102) and relapse OR 25 95%CI (2.9-214). Conclusion: Our study shows that pediatric patients with new onset diagnosis of cancer and patients with relapse have higher odds of all-cause mortality in the setting of COVID-19. This information would help develop an early identification of patients with cancer and COVID-19 with higher risk of mortality.

Distinguishing Carbohydrate Isomers with Rapid Hydrogen/Deuterium Exchange-Mass Spectrometry.

Carbohydrates play key roles in facilitating cellular functions, yet characterizing their structures is analytically challenging due to the presence of epimers, regioisomers, and stereoisomers. In-electrospray-hydrogen/deuterium exchange-mass spectrometry (in-ESI HDX-MS) is a rapid HDX method that samples solvated carbohydrates with minimal instrument modification. When applied to proteins, HDX is often measured after multiple time points to sample the dynamics of structures. Herein, we alter the HDX reaction time by modifying the spray-solvent conductivity, which changes the initial size of ESI droplets, and thus, the droplet lifetimes. We show that this change in droplet lifetime alters the magnitude of HDX for carbohydrate-metal adducts. Furthermore, we illustrate how monitoring HDX at multiple time points enables three trisaccharide isomers (melezitose, maltotriose, and isomaltotriose) to be distinguished. This work illustrates the feasibility of this method for characterizing solvated carbohydrates, including isomeric species which differ only by linkage.

Mitochondria, Energy and Cancer: The Relationship with Ascorbic Acid.

Ascorbic Acid (AA) has been used in the prevention and treatment of cancer with reported effectiveness. Mitochondria may be one of the principal targets of ascorbate's cellular activity and it may play an important role in the development and progression of cancer. Mitochondria, besides generating adenosine triphosphate (ATP), has a role in apoptosis regulation and in the production of regulatory oxidative species that may be relevant in gene expression. At higher concentrations AA may increase ATP production by increasing mitochondrial electron flux, also may induce apoptotic cell death in tumor cell lines, probably via its pro-oxidant action In contrast, at lower concentrations AA displays antioxidant properties that may prevent the activation of oxidant-induced apoptosis. These concentration dependent activities of ascorbate may explain in part the seemingly contradictory results that have been reported previously.

Differential efficacy of SSTR1, -2, and -5 agonists in the inhibition of C6 glioma growth in nude mice.

Somatostatin receptors (SSTR1-5) mediate antiproliferative effects. In C6 rat glioma cells, somatostatin is cytostatic in vitro via phosphotyrosine phosphatase-dependent inhibition of ERK1/2 activity mediated by SSTR1, -2, and -5. Here we analyzed the effects of SSTR activation on C6 glioma growth in vivo and the intracellular mechanisms involved, comparing somatostatin effects with selective agonists for SSTR1, -2, and -5 (BIM-23745, BIM-23120, BIM-23206) or receptor biselective compounds (SSTR1 and -2, BIM-23704; and SSTR2 and -5, BIM-23190). Nude mice subcutaneously xenografted with C6 cells were treated with somatostatin, SSTR agonists (50 µg, twice/day), or vehicle. Tumor growth was evaluated every 3 days for 19 days. The intracellular pathways responsible of SSTR effects in vivo were evaluated measuring Ki-67, phospho-ERK1/2, and p27(kip1) expression by immunohistochemistry in sections from explanted tumors. Somatostatin and SSTR1, -2, and -5 agonists strongly inhibited in vivo C6 tumor growth, intratumoral neovessel formation, Ki-67 expression, and ERK1/2 phosphorylation and induced upregulation of p27(Kip1), whereas only a modest activation of caspase-3 was observed. Somatostatin (acting on SSTR1, -2, and -5) displayed the highest efficacy; SSTR5 selective agonist showed a stronger effect than SSTR1 agonist, and SSTR2 agonist was less effective. On the other hand, SSTR1 and -2 agonists maximally reduced tumor neovascularization. The combined activation of SSTR1 and -2 showed a synergistic activity, reaching a higher efficacy than BIM-23206, whereas the simultaneous activation of SSTR2 and -5 resulted in a response resembling SSTR5 effects. Thus the simultaneous activation of different SSTRs inhibits glioma cell proliferation in vivo through both direct cytotostatic and antiangiogenic effects.

Rab18 is reduced in pituitary tumors causing acromegaly and its overexpression reverts growth hormone hypersecretion.

CONTEXT: Rab proteins regulate the sequential steps of intracellular membrane transport. Alterations of these GTPases and their associated proteins are emerging as the underlying cause for several human diseases involving dysregulated secretory activities. OBJECTIVE: Herein we investigated the role of Rab18, which negatively regulates hormone secretion by interacting with secretory granules, in relation to the altered functioning of tumoral pituitary somatotropes causing acromegaly. PATIENTS: A total of 18 patients diagnosed with pituitary tumors causing acromegaly (nine patients) or nonfunctioning adenomas (nine patients) underwent endoscopic transsphenoidal surgery. Adenomas were subsequently processed to evaluate Rab18 production in relation to GH secretion. RESULTS: We found that somatotropinoma cells are characterized by a high secretory activity concomitantly with a remarkably reduced Rab18 expression (15%) and protein content levels (30%), as compared with cells from nonfunctioning pituitary adenomas derived from patients with normal or reduced GH plasma levels (100%). Furthermore, immunoelectron microscopy revealed that Rab18 association with the surface of GH-containing secretory granules was significantly lower in somatotropes from acromegalies than nonfunctioning pituitary adenomas. Finally, we provide evidence that modulation of Rab18 gene expression can revert substantially the hypersecretory activity of cells because Rab18 overexpression reduced by 40% the capacity of cells from acromegalies to respond to GHRH stimulation. CONCLUSION: These results suggest that molecular alterations affecting individual components of the secretory granule traffic machinery can contribute to maintain a high level of GH in plasma. Accordingly, Rab18 constitutes a valuable target as a diagnostic, prognostic, and/or therapeutic tool for human acromegaly.

[Drug reaction with eosinophilia and systemic symptoms due to carbamazepine. Pediatric case]. / Síndrome de sensibilidad a fármacos con eosinofilia y síntomas sistémicos debido a la carbamazepina. Caso pediátrico.

Severe skin reactions include Stevens-Johnson Syndrome, toxic epidermal necrolysis and Drug reaction with Eosinophilia and Systemic Symptoms (DRESS) syndrome, which are uncommon in the pediatric population (incidence 1/1000- 10 000 children), but they have bad prognosis. Drug-sensitive Syndrome with eosinophilia and systemic symptoms consists in rash, hematological abnormalities, lymphadenopathy and organ involvement. We report the case of a 12-year-old male patient who developed this pathology after initiating anticonvulsant therapy with carbamazepine. We consider that it is important to be aware of this disease and to include it among the differential diagnoses in patients with similar conditions because this syndrome is life-threatening.

Entre las reacciones medicamentosas graves en la piel, se encuentran el síndrome de Stevens-Johnson, la necrólisis epidérmica tóxica y el síndrome de sensibilidad a fármacos con eosinofilia y síntomas sistémicos (drug reaction with eosinophilia and systemic symptoms; DRESS, por sus siglas en inglés), que son poco comunes en la población pediátrica (incidencia: 1/1000- 10 000 niños), sin embargo, tienen mal pronóstico. El síndrome de sensibilidad a fármacos con eosinofilia y síntomas sistémicos consiste en erupciones cutáneas, alteraciones hematológicas, linfadenopatía y afectación de órganos. Se presenta el caso de un paciente masculino de 12 años que desarrolló esta patología después de iniciar el tratamiento anticonvulsivo con carbamazepina. Se considera que es importante que el personal de la salud tenga conocimiento de esta enfermedad para que sea incluida entre los diagnósticos diferenciales de pacientes con afecciones similares, ya que este síndrome es potencialmente mortal.