ABSTRACT
O entendimento do metabolismo das bilirrubinas, desde sua formação quando da degradação das hemácias, passando por sua captação e conjugação nos hepatócitos até sua eliminação pelas vias biliares,é fundamental para os diversos diagnósticosque podem ser realizadosfrente uma síndrome ictérica. Classificando as síndromes ictéricas em dois grandes grupos, temos inicialmente aquelas devidas a hiperbilirrubinemia não-conjugada, como as doenças hemolíticas, as icterícias constitucionais e a icterícia do recém-nascido. Já as síndromes ictéricasdevidas a hiperbilirrubinemia conjugada também podem ser devidas a icterícias constitucionais, mas fundamentalmente a icterícias parenquimatosas com ausência de colestase ou colestases intra-hepáticas e extra-hepáticas. O trabalho clínico de coleta dos dados de história e exame físico é essen- I cial para os diferentes diagnósticos de icterícia, assim como a interpretação de exames laboratoriais e a correta indicação de exames complementares de imagem e/ou endoscópicos. Diferenciação entre as icterícias constitucionais, o diagnóstico etiológico das hepatites virais e os padrões mais freqüentes de icterícia encontrados na clínica são oferecidos em tabelas, assim como um algoritmo para a realização desse importante diagnóstico diferencial.
Subject(s)
Humans , Male , Female , Hyperbilirubinemia/metabolism , Jaundice/classification , Jaundice/diagnosis , Liver Diseases , Cholangiography , Cholestasis , Cholestasis, Extrahepatic , Cholestasis, Intrahepatic , Jaundice, Neonatal , Pancreatitis, Chronic , Physical ExaminationABSTRACT
OBJECTIVE: To determine whether serum levels of unconjugated bilirubin (UCB) can be decreased by enhancing fecal fat excretion. STUDY DESIGN: Gunn rats were fed a high-fat diet (control) or the same diet mixed with the lipase inhibitor orlistat. At regular intervals, plasma UCB concentrations were determined and 72-hour fat balances were performed. RESULTS: Orlistat treatment decreased plasma UCB concentrations (at 3 weeks; 100 mg/kg, -33%+/-8%, P<.05; 200 mg/kg, -46%+/-10%, P<.01). Within days of treatment, orlistat treatment increased fecal excretion of UCB (at day 3; +220%, P<.05). During 24 weeks of orlistat treatment (200 mg/kg diet), the plasma bilirubin concentrations were continuously approximately 35% lower than in control rats. Plasma UCB concentrations were inversely correlated with the amount of fecal fat excretion (n=12, r=-0.87, P<.001). CONCLUSIONS: In Gunn rats, orlistat treatment increases the fecal excretion of fat and enhances the disposal of UCB. This approach could lead to novel strategies for prevention and treatment of unconjugated hyperbilirubinemia in patients.
Subject(s)
Bilirubin/analysis , Bilirubin/blood , Enzyme Inhibitors/therapeutic use , Feces/chemistry , Hyperbilirubinemia/blood , Hyperbilirubinemia/drug therapy , Lactones/therapeutic use , Animals , Bile Ducts/drug effects , Bile Ducts/metabolism , Bilirubin/metabolism , Disease Models, Animal , Hyperbilirubinemia/metabolism , Male , Orlistat , Rats , Rats, Gunn , Time FactorsABSTRACT
O objetivo desta revisäo/atualizaçäo a respeito da abordagem clinica, laboratorial e terapeutica do recém-nascido icterico foi apresentar um roteiro didático, com a finalidade de se tentar esclarecer algumas dúvidas sobre a conduta na hiperbilirrubinemia neonatal, dando enfase aos pontos polêmicos da terapeutica
Subject(s)
Humans , Infant, Newborn , Hyperbilirubinemia/therapy , Jaundice, Neonatal/diagnosis , Phototherapy , Hyperbilirubinemia/metabolism , Jaundice, Neonatal/metabolism , Blood Transfusion/methodsABSTRACT
C-reactive protein rises in blood in an acute-phase response in adults, children, and neonates. In a prospective study of the influence of perinatal asphyxia, premature rupture of membranes, hyperbilirubinemia, and respiratory distress syndrome on levels of C-reactive protein in the neonate, we detected no confounding effect on the rise of C-reactive protein level in infants with these pathologic perinatal conditions, as compared with the results of a control group.
Subject(s)
C-Reactive Protein/analysis , Infant, Newborn, Diseases/metabolism , Cerebral Hemorrhage/metabolism , Female , Fetal Distress/metabolism , Fetal Membranes, Premature Rupture/metabolism , Humans , Hyperbilirubinemia/metabolism , Infant, Newborn , Pregnancy , Prospective Studies , Reference Values , Respiratory Distress Syndrome, Newborn/metabolismABSTRACT
1. Bolivian squirrel monkeys (BoSMs), which are animal models for Gilbert's syndrome, have 40% less hepatic bilirubin UDP-glucuronyltransferase (BR-UPPG-T) activity than Brazilian squirrel monkeys (BrSMs). 2. Although fasting results in similar decreases in hepatic UDP-glucose and UDP-glucuronate levels in both simian subspecies, increased activities (55%) of BR-UDPG-T are induced only in the fasted control BrSMs, which do not exhibit the marked fasting hyperbilirubinemia (FH). 3. Total hepatic bilirubin (BR) concentrations were 50% greater in both fed and fasted BoSMs when compared to BrSMs. 4. Hepatic unconjugated BR levels increase upon fasting only in Gilbert-like BoSMs, reaching concentrations twice that observed in BrSMs. 5. Elevated hepatic BR levels in fasted BoSMs may reflect BR overproduction or inadequate glucuronidation. 6. The increased BR-UDPG-T activity induced in BrSMs during fasting could compensate in-part for the UDPGA depletion and prevent the marked FH as observed in BoSMs.
Subject(s)
Bilirubin/metabolism , Fasting , Glucuronosyltransferase/metabolism , Hyperbilirubinemia/metabolism , Liver/enzymology , Uridine Diphosphate Glucuronic Acid/metabolism , Uridine Diphosphate Sugars/metabolism , Animals , Bilirubin/blood , Female , Glycogen/metabolism , Liver/metabolism , Saimiri , Uridine Diphosphate Glucose/metabolism , Uridine Diphosphate Glucuronic Acid/bloodABSTRACT
Pulmonary carbon monoxide (CO) excretion rates (VeCO) were 50% greater, on average, in Bolivian squirrel monkeys (BoSMs) which exhibit a unique fasting hyperbilirubinemia (FH), than in fasted control Brazilian squirrel monkeys (BrSMs). Since the catabolism of heme produces equimolar amounts of CO and bilirubin, the increased VeCOs are consistent with concurrent increases in endogenous bilirubin production rates. Tin-protoporphyrin, a competitive inhibitor of heme oxygenase, significantly decreased both the VeCO and serum bilirubin level in fasted BoSMs. Overproduction of bilirubin may be responsible in part for the marked FH in BoSMs.