Measuring and imaging of transcutaneous bilirubin, hemoglobin, and melanin based on diffuse reflectance spectroscopy.

Significance: Evaluation of biological chromophore levels is useful for detection of various skin diseases, including cancer, monitoring of health status and tissue metabolism, and assessment of clinical and physiological vascular functions. Clinically, it is useful to assess multiple different chromophores in vivo with a single technique or instrument. Aim: To investigate the possibility of estimating the concentration of four chromophores, bilirubin, oxygenated hemoglobin, deoxygenated hemoglobin, and melanin from diffuse reflectance spectra in the visible region. Approach: A new diffuse reflectance spectroscopic method based on the multiple regression analysis aided by Monte Carlo simulations for light transport was developed to quantify bilirubin, oxygenated hemoglobin, deoxygenated hemoglobin, and melanin. Three different experimental animal models were used to induce hyperbilirubinemia, hypoxemia, and melanogenesis in rats. Results: The estimated bilirubin concentration increased after ligation of the bile duct and reached around 18 mg/dl at 50 h after the onset of ligation, which corresponds to the reference value of bilirubin measured by a commercially available transcutaneous bilirubin meter. The concentration of oxygenated hemoglobin and that of deoxygenated hemoglobin decreased and increased, respectively, as the fraction of inspired oxygen decreased. Consequently, the tissue oxygen saturation dramatically decreased. The time course of melanin concentration after depilation of skin on the back of rats was indicative of the supply of melanosomes produced by melanocytes of hair follicles to the growing hair shaft. Conclusions: The results of our study showed that the proposed method is capable of the in vivo evaluation of percutaneous bilirubin level, skin hemodynamics, and melanogenesis in rats, and that it has potential as a tool for the diagnosis and management of hyperbilirubinemia, hypoxemia, and pigmented skin lesions.

Severe hyperbilirubinemia is associated with higher risk of contrast-related acute kidney injury following contrast-enhanced computed tomography.

INTRODUCTION: Contrast-induced acute kidney injury (CI-AKI) is associated with high risks of morbidity and mortality. Hyperbilirubinemia might have some renal protection but with no clear cutoff value for protection. Related studies are typically on limited numbers of patients and only in conditions of vascular intervention. METHODS: We performed this study to elucidate CI-AKI in patients after contrast-enhanced computed tomography (CCT). The outcomes were CI-AKI, dialysis and mortality. Patients were divided to three groups based on their serum levels of total bilirubin: ≤1.2 mg/dl, 1.3-2.0 mg/dl, and >2.0 mg/dl. RESULTS: We enrolled a total of 9,496 patients who had received CCT. Patients with serum total bilirubin >2.0 mg/dl were associated with CI-AKI. Those undergoing dialysis had the highest incidence of PC-AKI (p<0.001). No difference was found between the two groups of total bilirubin ≤1.2 and 1.3-2.0 mg/dl. Patients with total bilirubin >2mg/dl were associated with CI-AKI (OR = 1.89, 1.53-2.33 of 95% CI), dialysis (OR = 1.40, 1.01-1.95 of 95% CI) and mortality (OR = 1.63, 1.38-1.93 of 95% CI) after adjusting for laboratory data and all comorbidities (i.e., cerebrovascular disease, coronary artery disease, peripheral arterial disease, and acute myocardial infarction, diabetes mellitus, hypertension, gastrointestinal bleeding, cirrhosis, peritonitis, ascites, hepatoma, shock lung and colon cancer). We concluded that total bilirubin level >2 mg/dl is an independent risk factor for CI-AKI, dialysis and mortality after CCT. These patients also had high risks for cirrhosis or hepatoma. CONCLUSION: This is the first study providing evidence that hyperbilirubinemia (total bilirubin >2.0 mg/dl) being an independent risk factor for CI-AKI, dialysis and mortality after receiving CCT. Most patients with total bilirubin >2.0mg/dl had cirrhosis or hepatoma.

Early Amplitude-Integrated Electroencephalography Predicts Long-Term Outcomes in Term and Near-Term Newborns With Severe Hyperbilirubinemia.

BACKGROUND: We aimed to determine the predictive neurological prognostic value of early amplitude-integrated electroencephalography (aEEG) in term and near-term neonates with severe hyperbilirubinemia compared with cranial magnetic resonance imaging (MRI) and auditory brainstem response (ABR). METHODS: Infants of ≥35 weeks of gestation with severe hyperbilirubinemia (total serum bilirubin [TSB] ≥340 µmol/L) or with hyperbilirubinemia (TSB ≥257 µmol/L) in association with bilirubin-induced neurological dysfunction were recruited. All the subjects had an aEEG after being admitted to the neonatal intensive care unit, whereas cranial MRI and ABR were performed when TSB had come down to the normal range. All the infants were followed up to 12 months. RESULTS: During the study period, 77 of 83 infants were eligible, of which 71 had severe hyperbilirubinemia and six had hyperbilirubinemia in association with bilirubin-induced neurological dysfunction. Thirty-three infants were diagnosed with acute bilirubin encephalopathy (ABE), two of whom died of ABE, and 62 completed the follow-up, of which 12 infants had adverse outcomes. Sixty-four infants underwent aEEG, 40 infants had cranial MRI, and 39 infants had ABR. Logistic regression and the receiver-operator characteristic curve analysis showed that the ability of severely abnormal aEEG to predict adverse neurological outcomes in severe hyperbilirubinemia was no better than abnormal ABR, with a sensitivity of 35.7% versus 83.3%, a specificity of 92.0% versus 74.1%, a positive predictive value of 55.6% versus 58.8%, and a negative predictive value of 83.6% versus 90.9%. CONCLUSIONS: Early aEEG could predict adverse neurodevelopmental outcomes in neonates with severe hyperbilirubinemia, although the sensitivity was lower than ABR.

Liver stiffness measurements with supersonic shear wave elastography in the diagnosis of biliary atresia: a comparative study with grey-scale US.

OBJECTIVES: To prospectively assess the diagnostic performance of supersonic shear wave elastography (SSWE) in identifying biliary atresia (BA) among infants with conjugated hyperbilirubinaemia by comparing this approach with grey-scale ultrasonography (US). METHODS: Forty infants were analysed as the control group to determine normal liver stiffness values. The use of SSWE values for identifying BA was investigated in 172 infants suspected of having BA, and results were compared with the results obtained by grey-scale US. The Mann-Whitney U test, unpaired t-test, Spearman correlation and linear regression were also performed. RESULTS: The success rates of SSWE measurements in the control and study group were 100% (40/40) and 96.4% (244/253), respectively. Age, direct bilirubin, and indirect bilirubin all significantly correlated with SSWE in the liver (all P < 0.001). Linear regression showed that age had a greater effect on SSWE values than direct or indirect bilirubin. The diagnostic performance of liver stiffness values in identifying BA was lower than that of grey-scale US (area under the receiver operating characteristic curve [AUC], 0.790 vs 0.893, P < 0.001). CONCLUSIONS: SSWE is feasible and valuable in differentiating BA from non-BA. However, its diagnostic performance does not exceed that of grey-scale US. KEY POINTS: • SSWE could be successfully performed in an infant population. • For infants, the liver stiffness will increase as age increases. • SSWE is potentially useful in assessing infants suspected of biliary atresia. • SSWE is inferior to grey-scale US in identifying biliary atresia.

Monitoring the Response of Hyperbilirubinemia in the Mouse Brain by In Vivo Bioluminescence Imaging.

Increased levels of unconjugated bilirubin are neurotoxic, but the mechanism leading to neurological damage has not been completely elucidated. Innovative strategies of investigation are needed to more precisely define this pathological process. By longitudinal in vivo bioluminescence imaging, we noninvasively visualized the brain response to hyperbilirubinemia in the MITO-Luc mouse, in which light emission is restricted to the regions of active cell proliferation. We assessed that acute hyperbilirubinemia promotes bioluminescence in the brain region, indicating an increment in the cell proliferation rate. Immunohistochemical detection in brain sections of cells positive for both luciferase and the microglial marker allograft inflammatory factor 1 suggests proliferation of microglial cells. In addition, we demonstrated that brain induction of bioluminescence was altered by pharmacological displacement of bilirubin from its albumin binding sites and by modulation of the blood-brain barrier permeability, all pivotal factors in the development of bilirubin-induced neurologic dysfunction. We also determined that treatment with minocycline, an antibiotic with anti-inflammatory and neuroprotective properties, or administration of bevacizumab, an anti-vascular endothelial growth factor antibody, blunts bilirubin-induced bioluminescence. Overall the study supports the use of the MITO-Luc mouse as a valuable tool for the rapid response monitoring of drugs aiming at preventing acute bilirubin-induced neurological dysfunction.

Hypopituitarism in a neonate with hyperbilirubinemia and decreased level of consciousness: a case report study.

Decreased level of consciousness in neonates may result from different etiologies, including rare metabolic and hormonal disorder due to anterior pituitary insufficiency. In this case report, a five-day-old newborn boy was referred to the neonatal intensive care unit of Mustafa Khomeini hospital of Ilam, Iran. He had an open anterior fontanel with no history of prenatal and familial diseases. Clinical examination showed decreased level of consciousness so that this patient responded only to painful stimuli. Furthermore, unconsciousness, hyperbilirubinemia, and hypotonia were fully evident. Given the clinical findings and decreased level of consciousness, hormonal diagnostic tests and brain CT scan were performed for any evidence of hypopituitarism. Clinical and experimental findings were consistent with the generalized edema and pituitary insufficiency secondary to central hypothyroidism and cortisol deficiency. Based on the findings, the neonate was put on the hormonal replacement therapy and, as the result, all of the abnormal clinical symptoms disappeared. In conclusion, fatal neonatal diseases may be mistaken with unimportant clinical findings at the first examination. Therefore, comprehensive attention to all potential causes of such symptoms in the neonates should be given for early diagnosis and treatment, and to prevent any fatal and irreversible complications.

[Surgical tactics in patients with cholecystitis complicated by bilirubinemia].

Basing on experience of treatment of more than 11 000 patients there were analyzed its results in 248, who were admitted to the hospital in emergency for an acute cholecystitis and raising of a bilirubin level from 29.54 to 167.16 micromol/l. Miniinvasive tactic was applied, surgical treatment was divided on the stages: laparoscopic cholecystectomy with the common biliary duct (CBD) draining, postoperative transdrainage cholangiography (in 184 patients any calculi or other obstacles to the bile outflow were not revealed), endoscopic papillosphincterotomy--in accordance with the indications established. An acute intervention on CBD using miniaccess was needed in 4 patients only. The results were estimated as good and excellent.

The effect of lipophilicity on the hepatobiliary properties of iminodiacetic acid derivatives in the conditions of hyperbilirubinemia.

The partition coefficients (log P) of theoretically possible alkyliodinated iminodiacetic acid (IDA) derivatives and commercial IDA derivatives were calculated using two computer programs: ChemSketch Log P and ChemOffice Ultra. Newly synthesized ligands (DIETHYLIODIDA and DIISOPROPYLIODIDA) with the highest calculated log P were labeled with technetium-99m. The biodistribution and the influence of bilirubin on their biokinetics were investigated in rats and compared to corresponding results for commercial (99m)Tc-BROMIDA. Log P of (99m)Tc-complexes of synthesized ligands were determined experimentally as well as the protein binding. In comparison to (99m)Tc-BROMIDA, (99m)Tc-DIETHYLIODIDA has: (a) better biliary excretion (2.76±0.15%ID/g versus 1.83±0.10%ID/g); (b) faster hepatic clearance (2.90±0.21%ID/g versus 7.47±0.70%ID/g) and decreased biliary excretion (for 14% versus 22%) in conditions of hyperbilirubinemia after 15min. It is proved that (99m)Tc-DIISOPROPYLIODIDA has a prolonged hepatic transit time and decreased biliary excretion.

Positron emission tomography studies using (15R)-16-m-[11C]tolyl-17,18,19,20-tetranorisocarbacyclin methyl ester for the evaluation of hepatobiliary transport.

A quantitative positron emission tomography (PET) methodology was developed for in vivo kinetic analysis of hepatobiliary transport. Serial abdominal PET scans were performed on normal and multidrug resistance-associated protein 2 (Mrp2)-deficient rats after intravenous injection of (15R)-16-m-[(11)C]tolyl-17,18,19,20-tetranorisocarbacyclin methyl ester (15R-[(11)C] TIC-Me) as a radiotracer. 15R-[(11)C]TIC-Me was rapidly converted to its acid form in blood within 10 s. PET scans revealed that 15R-[(11)C]TIC was localized mainly in the liver within 5 min of injection. By 90 min, total radioactivity in bile of Mrp2-deficient rats was significantly reduced compared with controls. Metabolite analysis by thin-layer chromatography autoradiography showed that 15R-[(11)C]TIC is converted to at least three metabolites (M1, M2, and M3), and M2 and M3 are the major metabolites in plasma and bile, respectively. Hepatic uptake clearance of total radioactivity in normal rats was close to the hepatic blood flow rate and slightly higher than that in Mrp2-deficient rats. The intrinsic canalicular efflux clearance of M3 (CL(int,bile,M3)) in Mrp2-deficient rats was decreased to 12% of controls, whereas clearance of M2 was moderately decreased (54%). An in vitro transport assay detected ATP-dependent uptake of both M2 and M3 by rat Mrp2-expressing membrane vesicles. These results demonstrated that M3 is excreted primarily into the bile by Mrp2 in normal rats. We conclude that PET studies using 15R-[(11)C]TIC-Me could be useful for in vivo analyses of Mrp2-mediated hepatobiliary transport.

Diagnostic evaluation of infantile cholestasis.

OBJECTIVE: To evaluate diagnostic accuracy of some important clinical manifestations and different investigations in infantile cholestasis. MATERIAL AND METHOD: Infants diagnosed with prolong conjugated hyperbilirubinemia and admitted to Chiang Mai University Hospital between Jan 1999 and Feb 2003. Demographic and clinical data were recorded Routine biochemical tests, and serology for TORCHS infections were carried out. An abdominal ultrasonography, DISIDA scan and percutaneous/open liver biopsy were performed. Hyperechoic band at the level of portal bifurcation, named triangular cord (TC) sign was blindly assessed on ultrasonography by the same radiologist. The patients were diagnosed as BA if either operative findings of atretic common bile duct/ gallbladder or evidence of bile duct obstruction demonstrated by intraoperative cholangiography was noted RESULTS: Sixty-one patients were diagnosed as BA (n = 31) and NH (n = 30) with an average age at diagnosis of 88.6 and 63.1 days respectively. Concerning clinical presentations, only the presence of acholic stool was significantly different between BA and NH (p = 0.006). The GGT level of greater than 500 IU/L was significantly found in BA (p < 0.001). The acholic stool and GGT level more than 500 IU/L were highly specific for BA at 100 and 96.6% respectively. In addition, the sensitivity and specificity of US-TC and DISIDA scan were 87.4, 100 and 89. 7, 92.0% respectively. The accuracy for diagnosis of BA were highest by DISIDA scan (96.3) followed by US-TC (86.9), GGT level of > 500 IU/L(81.0) and acholic stool (80.3) in order CONCLUSION: There was no single laboratory investigation that could precisely make a definite diagnosis of BA. The acholic stool and GGT level of higher than 500 IU/L were highly specific for BA. The TC in ultrasound is noninvasive and easily available tests when combined with acholic stool and the GGT level is suggested plan of management.

Evaluation of the triangular cord sign in the diagnosis of biliary atresia.

BACKGROUND: Infantile cholestasis continues to represent a diagnostic challenge. It is very important to diagnose surgically correctable disorders, such as biliary atresia, in a timely manner to prevent progressive damage to the liver. It has been recently suggested that the triangular cord (TC) sign is a simple and useful tool in the diagnosis of biliary atresia. METHODS: We prospectively studied 65 infants presenting with conjugated hyperbilirubinemia (age range: 32-161 days). All patients underwent ultrasonographic examination with a 7.0-MHz transducer (Acuson, Mountain View, CA). The TC was defined as a triangular, or tubular, echogenic density seen immediately cranial to the portal vein bifurcation. RESULTS: The TC sign was identified in 25 infants, and all of them had histologic features suggestive of biliary atresia; the diagnosis was confirmed at surgery by gross morphology of hepatobiliary system, and liver biopsy, with or without intraoperative cholangiogram. Among the 40 patients who did not have the TC sign, 6 had paucity of the intrahepatic bile ducts. Three had alph-1-antitrypsin deficiency, and 31 had neonatal hepatitis. None of the 40 patients who did not have the TC sign developed acholic stools. Seven patients with biliary atresia were followed by ultrasonographic examination for 6 months after the Kasai procedure. The TC sign disappeared in all patients after the surgery; however, the TC sign reappeared in 3 patients who developed progressive cholestasis after the procedure. CONCLUSION: The TC sign is a simple, timesaving, and reliable diagnostic tool in the evaluation of infants with infantile cholestasis. The TC sign may also prove to be helpful in following patients after hepatoportoenterostomy. We suggest a new diagnostic strategy for patients suspected to have biliary atresia. When the TC sign is visualized, the patient should undergo intraoperative cholangiogram to confirm the diagnosis of biliary atresia, reserving percutaneous liver biopsy for those patients in whom the TC sign could not be detected.

Evaluation of 99mTc-mercaptoacetyltriglycine-biocytin as a new hepatobiliary imaging agent in mice coinjected with bilirubin.

We evaluated 99mTc-labeled mercaptoacetyltriglycine (99mTc-MAG3)-biocytin as a hepatobiliary imaging agent in the absence and presence of bilirubin in mice. We then compared its pharmacokinetic parameters; peak liver/heart activity ratio (rmax) and half clearance time (HCT) with those of 99mTc-labeled diisopropyl-iminodiacetic acid (99mTc-disofenin). Balb/c mice were injected intravenously with hepatobiliary agent (99mTc-MAG3-biocytin or 99mTc-disofenin) alone or in combination with bilirubin at two doses (7 and 14 mg/kg) dissolved in 5% human serum albumin. Images were acquired every 15 s for 30 min with a gamma-camera equipped with a pinhole collimator. Dynamic images showed rapid hepatic uptake of 99mTc-MAG3-biocytin, with rapid clearance from the blood and rapid excretion via the biliary system. Its hepatic uptake was not affected by bilirubin coinjection, whereas 99mTc-disofenin coinjected with bilirubin showed a higher blood background than 99mTc-disofenin alone. These qualitative findings were reflected in pharmacokinetic parameters, rmax and HCT. The rmax was obtained from plots of time versus liver/heart activity ratios obtained in equal-area regions of interest over the heart and liver. The HCT was calculated from the hepatic clearance curve from plots of time versus liver activity. 99mTc-MAG3-biocytin without bilirubin coinjection showed an rmax of 8.9+/-1.3 and an HCT of 399+/-36 s. These values did not change even when 14 mg/kg of bilirubin were coinjected. By contrast, the parameters for 99mTc-disofenin with bilirubin were significantly (p < 0.01) affected by 14 mg/kg of bilirubin coinjection: rmax was decreased from 7.9+/-2.5 to 1.4+/-0.2 and HCT was increased from 292+/-32 s to 782+/-133 s. 99mTc-MAG3-biocytin hepatobiliary scintigraphy in mice is not affected by bilirubin coinjection, and this hepatobiliary agent appears to offer promise for estimating hepatic function in patients with high bilirubin levels.

Diagnostic imaging to identify the cause of jaundice.

Imaging studies can be helpful in identifying the etiology of conjugated (direct) hyper-bilirubinemia. An elevated direct bilirubin level suggests obstructive jaundice, and ultrasound or computed tomographic (CT) imaging may identify the responsible structural lesion. Imaging can also be used to guide percutaneous biopsy. A cost-effective strategy for determining the cause of direct hyperbilirubinemia rests on ultrasound as the primary modality. Endoscopic retrograde cholangiopancreatography and CT are performed as follow-up studies only when necessary. Magnetic resonance imaging is rarely useful.

[New approaches to clinico-diagnostic and expert appraisal of the benign hyperbilirubinemia in pilot personnel]. / Novye podkhody k kliniko-diagnosticheskoi i ekcpertnoi otsenke dobrokachestvennoi giperbilirubinemii u letnogo sostava.

The study was aimed at improving the new clinico-diagnostic and expert approach to the benign hyperbilirubinemia in the pilot personnel. The 41 pilots of different aviation categories have been studied. There is indicated clinic of the benign hyperbilirubinemia in correlation with the presented laboratory indices. It is determined that laboratory diagnostics is the method selecting an examination of the given state, whereas the ultrasound scanning is critical to the diagnostic of the benign hyperbilirubinemia because it allows one to assess the whole structure of the hepatic tissue. Ultrasound examination proved to be the reliable technique of additional control of the liver state in the pilot personnel in a period between medical control commission.

[Value of cholescintigraphy in the differential diagnosis of direct hyperbilirubinemia in infancy]. / Wertigkeit der Choleszintigraphie in der Differentialdiagnose der direkten Hyperbilirubinämie des Säuglingsalters.

Cholescintigraphy using 99mTc-diethyl-, 99mTc-diisopropyl-, 99mTc-iodo-diethyl- and 99mTc-bro-motrimethyl-IDA was performed in 22 newborns and infants with direct hyperbilirubinaemia. Retrospective evaluation of 99mTc-diethyl- and 99mTc-diisopropyl-IDA (n = 18) showed an efficiency of 66% in the differentiation between extrahepatic biliary atresia and neonatal intrahepatic diseases if the hepatocyte-clearance index and transit time were taken into consideration; the sensitivity of detecting extrahepatic biliary atresia was 100%. Cholestyramine treatment (n = 9) did not increase the efficiency of the test. Efficiency was markedly reduced when the serum direct bilirubin level was above 5.5 mg/dl (94 mumol/l). The gall bladder was not visualized in 13 out of 18 examinations. The prospective and retrospective analysis of 99mTc-iodo-diethyl- and 99mTc-bromo-trimethyl-IDA revealed intrahepatic disease in all 6 infants with serum values up to 12.6 mg/dl (216 mumol/l) direct bilirubin; the gall bladder was not visualized in 4 out of 7 examinations.

The effect of bilirubin on biliary iodipamide excretion in the dog.

The effect of bilirubin on biliary iodipamide excretion and concentration was investigated in cholecystectomized dogs during complete bile diversion and constant bile salt replacement. A significant dose-dependent depression of both biliary iodipamide excretion rate and bile iodipamide concentration was found with increasing bilirubin dose. Whether or not bilirubin was infused at a constant of 0.1 mu moles/min/kg, the excretion rate and bile concentration of iodipamide was greatest with the largest 5.2 mu moles/min/kg iodipamide dose. Iodipamide had no significant effect on the bilirubin excretion rate, but because of its highly choleretic nature it had a dilution effect on the bilirubin bile concentration. This investigation suggests that a reduction of the iodipamide blood levels by either decreasing the dose or prolonging the infusion time will lead to poorer radiographic visualization of the biliary system in patients with unconjugated hyperbilirubinemia (prehepatic jaundice).