Introdução: Injúria Renal Aguda (IRA) é uma patologia grave e com elevada incidência em pacientes críticos. Apesar do avanço no conhecimento fisiopatológico ocorrido nas últimas décadas, pouco desse conhecimento foi traduzido em terapia para IRA já instalada. Medidas preventivas para evitar a progressão da IRA em momentos iniciais da injúria continuam a ser o principal foco na terapia da IRA. Nesse contexto, o diagnóstico e determinação precoce da gravidade da injúria renal são fundamentais para evitar a progressão para estágios mais graves e diminuir a morbidade e a mortalidade associadas à síndrome. Objetivos: O objetivo principal deste estudo, foi avaliar se o padrão de elevação dos biomarcadores permite a detecção precoce do diagnóstico de IRA. E os objetivos secundários foram avaliar se os biomarcadores podem auxiliar na predição da gravidade da IRA, na necessidade de diálise e óbito. Métodos: Estudo prospectivo, unicêntrico, entre janeiro de 2012 e janeiro de 2015. Foram avaliados e incluídos pacientes com critérios de alto risco para IRA nas Unidades de Terapia Intensiva (UTI) clínicas e cirúrgicas. Características clínicas e demográficas foram avaliadas no início da internação e a evolução laboratorial e hemodinâmica dos pacientes foram acompanhadas durante as primeiras 48 horas de internação na UTI. Os biomarcadores precoces de injuria renal aguda séricos e urinários, assim como a bioquímica e microscopia urinária, foram analisados a cada 12 horas durante este período. IRA foi definida pelo critério da creatinina do KDIGO. Episódios de IRA com resolução em 3 dias foram definidos como transitória (IRAt) e episódios com duração maior que 3 dias como persistente (IRAp). Resultados: Durante o período estudado foram avaliados 376 pacientes, dos quais 70 preencheram os critérios de inclusão e 32 (46%) evoluiram com IRA. Noventa porcento dos pacientes incluídos no estudo foram pacientes em pós-operatorio. Não houve diferença nas características basais entre os grupos com IRA e sem IRA. A fração de excreção de sódio (FENa) foi maior no grupo com IRAp à admissão, entretanto foi menor que 1% em todos os grupos. O gradiente transtubular de potássio (TTKG) foi significativamente maior no 4º e 5º momentos no grupo com IRAp quando comparado aos outros grupos. Os níveis de Neutrophil Gelatinase-Associated Lipocalin (NGAL), tanto séricos como urinários foram significativamente maiores no grupo com IRAp em relação ao grupo IRAt e não IRA, assim como Liver-type Fatty Acid-Binding Protein (L-FABP) e o Kidney Injury Molecule-1 (KIM-1). Não se constatou diferença significativa entre os grupos em relação ao Tissue Inhibitor of Metalloproteinases-1 (TIMP-1), alfa e pi-Glutathione-transferase (alfa- GST e pi-GST). Entre os pacientes com diagnóstico de IRA pela creatinina sérica nos primeiros 2 dias de UTI, o emprego do NGAL sérico e/ou urinário possibilitaram o diagnóstico mais precoce da IRA em relação à creatinina em 59,3 % e 27,6% dos pacientes, respectivamente. O NGAL sérico e urinário foram preditores independentes de mortalidade e de necessidade de terapia de substituição renal à análise multivariada. Conclusão: Na IRA persistente a bioquímica urinária apresentou diferenças em relação à FENa e ao TTKG. A performance do NGAL sérico e urinário nesta população conseguiu antecipar o diagnóstico da IRA em relação ao critério da creatinina. O NGAL sérico e urinário foram preditores independentes de necessidade de terapia de substituição renal e mortalidade / Background: Acute kidney injury (AKI) is a syndrome with high incidence in critical ill patients and associated with severe complications. Although important advances has been achieved in the understanding of its physiopathology, this knowledge have not resulted in improvements in therapy for AKI. Preventive measures to avoid AKI progress at the initial phases of injury are still the main goal of AKI therapy. Therefore, early diagnosis and assessment of disease severity are essential to prevent disease progression and to reduce morbidity and mortality. Objectives: The main goal of this study was to evaluate whether a panel of biomarkers would allow early detection of AKI. Secondary endpoints were to evaluate whether biomarkers can predict the severity of AKI, need for dialysis and mortality in high-risk critical ill patients. Methods: We performed a prospective study between January 2012 and 2015. We recruited patients admitted in intensive care unit (ICU) with high risk for AKI. Clinical and demographic characteristics were recorded. Urinary biomarkers and urine biochemistry were measured sequentially every 12 hours during the first two days of ICU stay. AKI was defined according to KDIGO creatinine criteria. Patients were classified as having transitory AKI (tAKI) or persistent AKI (pAKI). Results: Of the 376 patients initially evaluated, 70 met the inclusion criteria. Thirty-two patients (46 %) met KDIGO criteria for AKI. Ninety percent of the patients in this study were surgical. The baseline characteristics were similar among all groups. The fractional excretion of sodium (FENa) was higher in pAKI group, and it was < 1% in all groups. In patients who developed pAKI the transtubular potassium gradient (TTKG) was significantly higher at 36h and 48h. Plasma and urinary Neutrophil Gelatinase-Associated Lipocalin (NGAL), Liver-type Fatty Acid-Binding Protein (L-FABP) and Kidney Injury Molecule-1 (KIM-1) were significantly higher in the pAKI group as compared to the t AKI and non AKI groups in different times of evaluation. There was no difference in levels of Tissue Inhibitor of Metalloproteinases-1 (TIMP-1), alfa and pi-Glutathione-transferase (alfa-GST and pi-GST) within the groups during the first 48 h of ICU admission. Based on the cutoff levels, plasma and urinary NGAL would determine earlier diagnosis in 59.3% and 27.6% patients in the first two days of ICU, respectively. In the multivariate analysis, plasma and urinary NGAL were independent predictors of need for dialysis and mortality. Conclusions: In this study population, persistent AKI have alterations in urinary physicochemical parameters such as FENa and TTKG. Plasma and urinary NGAL were early biomarkers for AKI diagnosis. Plasma and urinary NGAL were independent predictors of dialysis and mortality

Introdução: Injúria Renal Aguda (IRA) é uma patologia grave e com elevada incidência em pacientes críticos. Apesar do avanço no conhecimento fisiopatológico ocorrido nas últimas décadas, pouco desse conhecimento foi traduzido em terapia para IRA já instalada. Medidas preventivas para evitar a progressão da IRA em momentos iniciais da injúria continuam a ser o principal foco na terapia da IRA. Nesse contexto, o diagnóstico e determinação precoce da gravidade da injúria renal são fundamentais para evitar a progressão para estágios mais graves e diminuir a morbidade e a mortalidade associadas à síndrome. Objetivos: O objetivo principal deste estudo, foi avaliar se o padrão de elevação dos biomarcadores permite a detecção precoce do diagnóstico de IRA. E os objetivos secundários foram avaliar se os biomarcadores podem auxiliar na predição da gravidade da IRA, na necessidade de diálise e óbito. Métodos: Estudo prospectivo, unicêntrico, entre janeiro de 2012 e janeiro de 2015. Foram avaliados e incluídos pacientes com critérios de alto risco para IRA nas Unidades de Terapia Intensiva (UTI) clínicas e cirúrgicas. Características clínicas e demográficas foram avaliadas no início da internação e a evolução laboratorial e hemodinâmica dos pacientes foram acompanhadas durante as primeiras 48 horas de internação na UTI. Os biomarcadores precoces de injuria renal aguda séricos e urinários, assim como a bioquímica e microscopia urinária, foram analisados a cada 12 horas durante este período. IRA foi definida pelo critério da creatinina do KDIGO. Episódios de IRA com resolução em 3 dias foram definidos como transitória (IRAt) e episódios com duração maior que 3 dias como persistente (IRAp). Resultados: Durante o período estudado foram avaliados 376 pacientes, dos quais 70 preencheram os critérios de inclusão e 32 (46%) evoluiram com IRA. Noventa porcento dos pacientes incluídos no estudo foram pacientes em pós-operatorio. Não houve diferença nas características basais entre os grupos com IRA e sem IRA. A fração de excreção de sódio (FENa) foi maior no grupo com IRAp à admissão, entretanto foi menor que 1% em todos os grupos. O gradiente transtubular de potássio (TTKG) foi significativamente maior no 4º e 5º momentos no grupo com IRAp quando comparado aos outros grupos. Os níveis de Neutrophil Gelatinase-Associated Lipocalin (NGAL), tanto séricos como urinários foram significativamente maiores no grupo com IRAp em relação ao grupo IRAt e não IRA, assim como Liver-type Fatty Acid-Binding Protein (L-FABP) e o Kidney Injury Molecule-1 (KIM-1). Não se constatou diferença significativa entre os grupos em relação ao Tissue Inhibitor of Metalloproteinases-1 (TIMP-1), alfa e pi-Glutathione-transferase (alfa- GST e pi-GST). Entre os pacientes com diagnóstico de IRA pela creatinina sérica nos primeiros 2 dias de UTI, o emprego do NGAL sérico e/ou urinário possibilitaram o diagnóstico mais precoce da IRA em relação à creatinina em 59,3 % e 27,6% dos pacientes, respectivamente. O NGAL sérico e urinário foram preditores independentes de mortalidade e de necessidade de terapia de substituição renal à análise multivariada. Conclusão: Na IRA persistente a bioquímica urinária apresentou diferenças em relação à FENa e ao TTKG. A performance do NGAL sérico e urinário nesta população conseguiu antecipar o diagnóstico da IRA em relação ao critério da creatinina. O NGAL sérico e urinário foram preditores independentes de necessidade de terapia de substituição renal e mortalidade / Background: Acute kidney injury (AKI) is a syndrome with high incidence in critical ill patients and associated with severe complications. Although important advances has been achieved in the understanding of its physiopathology, this knowledge have not resulted in improvements in therapy for AKI. Preventive measures to avoid AKI progress at the initial phases of injury are still the main goal of AKI therapy. Therefore, early diagnosis and assessment of disease severity are essential to prevent disease progression and to reduce morbidity and mortality. Objectives: The main goal of this study was to evaluate whether a panel of biomarkers would allow early detection of AKI. Secondary endpoints were to evaluate whether biomarkers can predict the severity of AKI, need for dialysis and mortality in high-risk critical ill patients. Methods: We performed a prospective study between January 2012 and 2015. We recruited patients admitted in intensive care unit (ICU) with high risk for AKI. Clinical and demographic characteristics were recorded. Urinary biomarkers and urine biochemistry were measured sequentially every 12 hours during the first two days of ICU stay. AKI was defined according to KDIGO creatinine criteria. Patients were classified as having transitory AKI (tAKI) or persistent AKI (pAKI). Results: Of the 376 patients initially evaluated, 70 met the inclusion criteria. Thirty-two patients (46 %) met KDIGO criteria for AKI. Ninety percent of the patients in this study were surgical. The baseline characteristics were similar among all groups. The fractional excretion of sodium (FENa) was higher in pAKI group, and it was < 1% in all groups. In patients who developed pAKI the transtubular potassium gradient (TTKG) was significantly higher at 36h and 48h. Plasma and urinary Neutrophil Gelatinase-Associated Lipocalin (NGAL), Liver-type Fatty Acid-Binding Protein (L-FABP) and Kidney Injury Molecule-1 (KIM-1) were significantly higher in the pAKI group as compared to the t AKI and non AKI groups in different times of evaluation. There was no difference in levels of Tissue Inhibitor of Metalloproteinases-1 (TIMP-1), alfa and pi-Glutathione-transferase (alfa-GST and pi-GST) within the groups during the first 48 h of ICU admission. Based on the cutoff levels, plasma and urinary NGAL would determine earlier diagnosis in 59.3% and 27.6% patients in the first two days of ICU, respectively. In the multivariate analysis, plasma and urinary NGAL were independent predictors of need for dialysis and mortality. Conclusions: In this study population, persistent AKI have alterations in urinary physicochemical parameters such as FENa and TTKG. Plasma and urinary NGAL were early biomarkers for AKI diagnosis. Plasma and urinary NGAL were independent predictors of dialysis and mortality

Στην παρούσα διατριβή μελετήθηκε η έκφραση του παράγοντα αναστολής της μετανάστευσης των μακροφάγων (MIF) στον ιστό από ρινικό πολύποδα αλλά και στον φυσιολογικό ρινικό βλεννογόνο, καθώς και η ικανότητα αυτού να εξουδετερώνει την ανασταλτική δράση των γλυκοκορτικοειδών (ΓΚ) στην επαγόμενη από διάφορους αυξητικούς παράγοντες παραγωγή διαμεσολαβητών, όπως η IL-6 η MMP-1, η MMP-3 το κολλαγόνο τύπου-Ι και ο TIMP-1, που εμπλέκονται στη παθογένεια του ρινικού πολύποδα (ΡΠ). Ο MIF ανιχνεύθηκε στο μέσο καλλιέργειας όλων των ιστών και σε όλα τα εκχυλίσματα. Η έκφρασή του ήταν αυξημένη στον ρινικό πολύποδα σε σχέση με τον φυσιολογικό ρινικό βλεννογόνο. O TGF-β1 προκάλεσε δοσο- και χρονο-εξαρτώμενη αύξηση των επιπέδων της IL-6 του TIMP-1 και του κολλαγόνου τύπου-Ι, και παράλληλα ο TNF-α προκάλεσε δοσο- αλλά και χρονο-εξαρτώμενη διέγερση στην παραγωγή της IL-6 του TIMP-1 και των μεταλλοπρωτεασών MMP-1 και MMP-3. Η δεξαμεθαζόνη προκάλεσε στατιστικά σημαντική και δοσοεξαρτώμενη μείωση της επαγόμενης από τον TGF-β1 και TNF-α, παραγωγής της IL-6 του TIMP-1 του κολλαγόνου τύπου-Ι και των μεταλλοπρωτεασών MMP-1 και MMP-3. Διερευνώντας τον μηχανισμό μέσω του οποίου η δεξαμεθαζόνη ασκεί την κατασταλτική της δράση στην επαγόμενη τόσο από τον TGF-β1 όσο και από τον TNF-α, παραγωγή της IL-6, φάνηκε πως αυτή εκδηλώνεται κυρίως μέσω της επαγωγής αλλά και της προστασίας της ΜΚΡ-1 και κατά συνέπεια της καταστολής του μονοπατιού των ΜΑΡΚ και της ενεργοποίησης του ΑΡ-1, και λιγότερο μέσω της καταστολής της ενεργοποίησης του NF-κB. Ο ISO-1, ένας αναστολέας της δράσης του MIF, ενίσχυσε σημαντικά την κατασταλτική επίδραση της δεξαμεθαζόνης στα επίπεδα της IL-6 και του TIMP-1 στο μέσο καλλιέργειας ιστού από ΡΠ, ενώ αντίθετα προκάλεσε αναστροφή της κατασταλτικής δράσης της δεξαμεθαζόνης, η οποία ήταν στατιστικά σημαντική για την ΜΜΡ-1 όχι όμως και για την ΜΜΡ-3. Η ενίσχυση της κατασταλτικής δράσης της δεξαμεθαζόνης παρουσία του ISO-1, που κυμάνθηκε από 15.0% έως 20.5% θα πρέπει μάλλον να οφείλεται στην αναστολή του ενδογενούς MIF από τον ISO-1. Συμπερασματικά, η παρουσία του MIF στον ιστό του ρινικού πολύποδα, φαίνεται να εξασθενίζει το κατασταλτικό αποτέλεσμα της δεξαμεθαζόνης στην παραγωγή IL-6 και TIMP-1 από αυτόν τον ιστό, ενώ η ταυτόχρονη χρήση του αναστολέα του MIF, ISO-1 οδηγεί σε μια περαιτέρω ενίσχυση της κατασταλτικής δράσης της δεξαμεθαζόνης. Έτσι, είναι λογικό κατ΄αρχήν, να προταθεί πως η δημιουργία ενός φαρμακευτικού σχήματος που περιέχει κορτιζόλη και ένα αναστολέα του MIF, θα μπορούσε να είναι πιο αποτελεσματικό στην θεραπεία της ΡΠ. Απαιτούνται περαιτέρω πειράματα με συνδυασμό ΓΚ και αναστολέων του MIF για να μελετηθεί η επίδρασή τους στη παραγωγή και άλλων παραγόντων που εμπλέκονται στη παθογένεια της ΡΠ προκειμένου να εξαχθούν ασφαλέστερα συμπεράσματα. / In the present study we investigated the expression of macrophage migration inhibitory factor (MIF) in nasal polyp tissues and also in normal nasal mucosa. The ability of MIF to neutralize the inhibitory effect of glucocorticoids on various growth factors induced expression of IL-6, TIMP-1, collagen type-I and matrix metalloproteinases MMP-1 and MMP-3, involved in the pathogenesis of nasal polyps, was studied. MIF was detected in all polyp tissue extracts and tissue culture conditioned media and its expression was increased in nasal polyps compared with normal nasal mucosa. TGF-b1 caused a dose-and time-dependent increase in levels of IL-6 of TIMP-1 and collagen type-I, while the TNF-a induced a dose-and time-dependent stimulation in the production of IL-6 of TIMP-1 and metalloproteinases MMP-1 and MMP-3. Dexamethasone caused a statistically significant and dose-dependent reduction induced by TGF-b1 and TNF-a, production of IL-6 of TIMP-1 of collagen type-I and the metalloproteinases MMP-1 and MMP-3. Investigating the mechanism by which dexamethasone exercises the suppressive action on both induced by TGF-b1 and by TNF-a, production of IL-6, showed that this occurs mainly through the induction and protection of MKP-1 and hence the suppression of the MAPK pathway and activation of AP-1, and less through the suppression of the activation of NF-kB. The ISO-1, an inhibitor of the action of MIF, significantly enhanced the suppressive effect of dexamethasone on the levels of IL-6 and TIMP-1 in tissue culture medium from nasal polyps. In contrary, ISO-1 induced inversion of the suppresive action of dexamethasone, which was statistically significant for MMP-1 but not for MMP-3. Enhancing of the suppresive action of dexamethasone in the presence of ISO-1, which ranged from 15.0% to 20.5% would probably be due to inhibition of endogenous MIF by ISO-1. In conclusion, the presence of MIF in nasal polyp tissue, appears to attenuate the suppressor effect of dexamethasone on the production of IL-6 and TIMP-1by this tissue, while simultaneously using the inhibitor of MIF, ISO-1 leads to an enhancement of dexamethasone activity. Therefore, it is reasonable to propose that the creation of a pharmaceutical regimen containing cortisol and an inhibitor of MIF, might be more effective in the treatment of nasal polyposis. Of course, requires further experiments with a combination of glucocorticoids and MIF inhibitors to study their effect on production of other factors involved in the pathogenesis of nasal polyposis in order to draw safer conclusions.