Evaluation of abnormal liver function tests

Neonatal Dubin-Johnson Syndrome and its Differentiation from Biliary Atresia

BACKGROUND AND AIMS

The aim was to determine if liver biochemistry indices can be used as biomarkers to help differentiate patients with neonatal Dubin-Johnson syndrome (nDJS) from those with biliary atresia (BA).

METHODS

Patients with genetically-confirmed nDJS or cholangiographically confirmed BA were retrospectively enrolled and randomly assigned to discovery or verification cohorts. Their liver chemistries, measured during the neonatal period, were compared. Predictive values were calculated by receiver operating characteristic curve analysis.

RESULTS

A cohort of 53 nDJS patients was recruited, of whom 13 presented with acholic stools, and 14 underwent diagnostic cholangiography or needle liver biopsy to differentiate from BA. Thirty-five patients in the cohort, with complete biochemical information measured during the neonatal period, were compared with 133 infants with cholangiographically confirmed BA. Total and direct bilirubin, alanine aminotransferase (ALT), aspartate aminotransferase (AST), total bile acids, alkaline phosphatase, and gamma-glutamyl transferase were significantly lower in nDJS than in BA. In the discovery cohort, the areas under the curve for ALT and AST were 0.908 and 0.943, respectively. In the validation cohort, 13/15 patients in the nDJS group were classified as nDJS, and 10/53 in the BA control group were positive (p<0.00001) with an ALT biomarker cutoff value of 75 IU/L. Thirteen of 15 patients were classified as nDJS and none were classified positive in the BA group (13/15 vs. 0/53, p<0.00001) with an AST cutoff of 87 IU/L.

CONCLUSIONS

Having assembled and investigated the largest cohort of nDJS patients reported to date, we found that nDJS patients could be distinguished from BA patients using the serum AST level as a biomarker. The finding may be clinically useful to spare cholestatic nDJS patients unnecessary invasive procedures.

Liposome cocktail activator modulates hepatocytes and remodels the microenvironment to mitigate acute liver failure

Acute liver failure (ALF) is a mortal and critical hepatic disease, in which oxidative stress, inflammation storm and hepatocyte death are crucial in the pathogenesis. Hence, in contrast to the control of a single link, a combination therapy targeting multiple pathogenic links of the disease will be a favorable means to control the progression of the disease. In this study, we constructed dimethyl itaconate-loaded liposomes modified with dodecyl gallate as a cocktail activator to investigate its functional role in acetaminophen (APAP)-induced ALF. Our results demonstrated that the cocktail activator acted on hepatocytes and triggered cocktail efficacy, thereby simultaneously attenuating APAP-induced hepatocyte damage and remodeling the damage microenvironment. The cocktail activator could effectively scavenge reactive oxygen species, inhibit excessive inflammatory responses and reduce cell death in impaired hepatocytes for detoxification. More importantly, the cocktail activator could remodel the damage microenvironment, thus further promoting hepatocyte expansion and specifically switching macrophages from the M1 to M2 phenotype for a favorable liver regeneration of ALF. Furthermore, in APAP-induced ALF mouse model, the cocktail activator improved liver function, alleviated histopathological damage and increased survival rate. In summary, these findings indicate that the cocktail activator may provide a promising therapeutic approach for ALF treatment as a nanomedicine.

Short-Term Neonatal Oral Administration of Oleanolic Acid Protects against Fructose-Induced Oxidative Stress in the Skeletal Muscles of Suckling Rats

Nutritional manipulations in the neonatal period are associated with the development of negative or positive health outcomes later in life. Excessive fructose consumption has been attributed to the increase in the global prevalence of metabolic syndrome (MetS) and the development of oxidative stress. Oleanolic acid (OA) has anti-diabetic and anti-obesity effects. We investigated the protective potential of orally administering OA in the neonatal period, to prevent fructose-induced oxidative stress, adverse health outcomes and maturation of the gastrointestinal tract (GIT) in suckling rats. Seven-day old Sprague-Dawley rats (N = 30) were gavaged daily with 10 mL/kg of: distilled water (DW), oleanolic acid (OA; 60 mg/kg), high fructose solution (HF; 20% w/v), or OAHF for 7 days. On day 14, tissue samples were collected to determine clinical health profiles, hepatic lipid content, and activity of anti-oxidant enzymes. Furthermore, biomarkers of oxidative stress and anti-oxidant capacity in the skeletal muscles were assessed. The gastrointestinal tract (GIT) morphometry was measured. Rats in all groups grew over the 7-day treatment period. There were no significant differences in the terminal body masses, GIT morphometry, surrogate markers of general health, liver lipid content across all treatment groups (p < 0.05). Neonatal fructose administration decreased the activity of catalase, depleted GSH and increased lipid peroxidation. However, the level of GSH and catalase activity were improved by neonatal OA treatment. Short-term oral OA administration during the critical developmental period protects against fructose-induced oxidative stress without adverse effects on health outcomes associated with MetS or precocious development of the GIT in suckling male and female rats.

Ophthalmological side effects of interferon therapy of chronic hepatitis C

BACKGROUND

Egypt has one of the highest prevalence of hepatitis C virus (HCV) worldwide. Ophthalmological side effects are recognized complications of interferon (IFN) therapy. This study aimed to evaluate IFN-induced ophthalmological manifestations in patients receiving PEGylated interferon (PEG IFN) and ribavirin (RBV) and to assess the effect of IFN duration, response and systemic risk factors on the severity.

METHODS

We retrospectively analyzed 100 patients with chronic HCV who were candidates for PEG-IFN and RBV therapy. All patients were subjected to clinical and ophthalmological examination, laboratory investigations, abdominal ultrasound, colored fundus photography and fundus fluorescein angiography, follow up was made at weeks 12, 24, and 48 of treatment.

RESULTS

IFN-induced retinopathy had been found in (9/100; 9%), 5 (5/9; 55.5%) of them had bilateral lesions, (3/9; 33.3%) were treatment responders and (6/9; 66.6%) non responders. The time of retinopathy appearance was mainly at W12. Retinopathy was asymptomatic in most of the affected patients (7/9; 77.77%) and reversible, cotton wool spots was the major associated sign. Patients with older age, DM and or HTN, and non-responders to antiviral therapy were associated with more severe retinopathy.

CONCLUSIONS

Retinopathy is not a rare complication of IFN therapy for chronic HCV infection, but fortunately it's asymptomatic and reversible. Ophthalmological assessment at base-line and at follow up during IFN treatment is very important.

Abnormal liver test results on routine screening

Primary care physicians are often the first healthcare professionals to see abnormalities that show up in routine serum liver testing--results that may indicate liver disease. In this article, Drs Mallory, Lee, and Kowdley offer a practical approach to evaluating abnormal levels of markers of hepatocellular injury, cholestasis, and liver synthetic function. They also explore the considerations that might prompt physicians to request a liver biopsy.

Destruction of the hepatocyte junction by intercellular invasion of Leptospira causes jaundice in a hamster model of Weil's disease

Weil's disease, the most severe form of leptospirosis, is characterized by jaundice, haemorrhage and renal failure. The mechanisms of jaundice caused by pathogenic Leptospira remain unclear. We therefore aimed to elucidate the mechanisms by integrating histopathological changes with serum biochemical abnormalities during the development of jaundice in a hamster model of Weil's disease. In this work, we obtained three-dimensional images of infected hamster livers using scanning electron microscope together with freeze-cracking and cross-cutting methods for sample preparation. The images displayed the corkscrew-shaped bacteria, which infiltrated the Disse's space, migrated between hepatocytes, detached the intercellular junctions and disrupted the bile canaliculi. Destruction of bile canaliculi coincided with the elevation of conjugated bilirubin, aspartate transaminase and alkaline phosphatase levels in serum, whereas serum alanine transaminase and γ-glutamyl transpeptidase levels increased slightly, but not significantly. We also found in ex vivo experiments that pathogenic, but not non-pathogenic leptospires, tend to adhere to the perijunctional region of hepatocyte couplets isolated from hamsters and initiate invasion of the intercellular junction within 1 h after co-incubation. Our results suggest that pathogenic leptospires invade the intercellular junctions of host hepatocytes, and this invasion contributes in the disruption of the junction. Subsequently, bile leaks from bile canaliculi and jaundice occurs immediately. Our findings revealed not only a novel pathogenicity of leptospires, but also a novel mechanism of jaundice induced by bacterial infection.

Antenatal detection of abnormal liver function tests - a marker for poor perinatal outcome

The purpose of this study was to examine (a) the incidence of liver disease diagnosed in our antenatal population, (b) the diagnostic value of initial symptoms and liver function tests (LFTs), (c) the adequacy of investigation and management of the liver disorder and (d) the obstetric and neonatal outcome in this group of patients. Women with abnormal LFTs that delivered at our hospital over a 2-year period were identified from computerised hospital records and data was obtained from chart review. Forty-six out of a total of 13 181 (0.35%) women had liver disease diagnosed in pregnancy: Diagnoses included intrahepatic cholestasis of pregnancy (13), pre-eclampsia and the HELLP syndrome (eight), acute fatty liver of pregnancy (three), hyperemesis gravidarum (one), hepatitis C (13), B (four) and hepatitis A (one), cholelithiasis (two) and hepatitis of unknown aetiology (one). Symptoms at presentation were more predictive of the final diagnosis than the initial LFT profile. Investigation of the liver disorder was incomplete in 50% of cases. One mother required intensive care for 6 weeks postpartum and three others had significant postpartum haemorrhage. There was one neonatal death and 24 neonates were admitted to the special care baby unit. Eighteen women attended for their postnatal check up at 6 weeks. Eight of these women were referred to a hepatologist. Detection of liver disease in pregnancy identifies a group at risk of poor neonatal and maternal outcome. Structured guidelines should be implemented in obstetric units to facilitate appropriate investigation, treatment and referral patterns for these women.

Cytochrome c: a non-invasive biomarker of drug-induced liver injury

Limitations of existing biomarkers to detect liver injury in experimental animals highlight the need for additional tools to predict human toxicity. The utility of cytochrome c (cyt c) as a biomarker in serum and urine was evaluated in two rodent liver injury models. Adult Sprague-Dawley rats treated with acetaminophen or D-galactosamine (GalN) showed dose- and time-dependent histomorphological changes and TUNEL staining in liver consistent with hepatocellular necrosis, apoptosis and inflammation up to 72 h. Matching changes in serum alanine transaminase (ALT), aspartate transaminase (AST) and cyt c peaked at 24 h for either drug at the highest dose, cyt c falling rapidly at 48 hours with ALT and AST remained high. Intracellular transit of cyt c from mitochondria to the cytoplasm in damaged hepatocytes, and then to peripheral circulation, was observed by immunohistochemistry. Correlation coefficients between cyt c and serum diagnostic tests indicate the liver to be the primary source of cyt c. Urinary analysis for cyt c revealed time-dependent increase at 6 h, peaking at 24 h in GalN-treated rats in contrast with irregular patterns of urinary ALT and AST activity. Histological changes detected at 6 h preceded altered ALT, AST and cyt c at 12 and 18 h, respectively, in GalN-treated rats. These studies demonstrate cyt c to be a useful indicator of hepatic injury in rodents and support its utility as a non-invasive predictor of drug-induced hepatotoxicity, when utilized as a potential urinary biomarker.

Liver Function Tests

Liver diseases are common, and currently represent the 12th leading cause of death in the United States. However, numerous hepatic disorders exist, and differential diagnosis often is difficult. Moreover, because laboratory testing is routine, an abnormal serum transaminase or alkaline phosphatase in patients without clinical symptoms is not uncommon. Although liver function tests are critical in recognizing the presence of liver disease and its specific diagnosis, the interpretation of the tests may be confusing and difficult. Furthermore, not all persons with one or more test abnormalities actually have liver disease. In this review, liver function tests and an approach to their interpretation are discussed.

Discordance between ALT values and fibrosis in liver transplant recipients treated with ribavirin for recurrent hepatitis C

Hepatitis C virus (HCV) recurrence is a serious problem after orthotopic liver transplantation (OLT). The role of ribavirin as a single agent to treat recurrent HCV is controversial. Our aim was to evaluate the correlation between alanine aminotransferase (ALT) levels and histological findings in OLT recipients treated with ribavirin monotherapy for recurrent HCV. The mean [+/- standard error (SE)] age of 11 patients was 50.1 (SE +/- 8.6) years. The estimated mean dose and duration of ribavirin treatment (+/- SE) was 661.5 (+/- 52.5) mg and 20.4 (+/- 1.7) months, respectively. Five patients required either dose reduction or erythropoietin. We found a significant decrease of mean (+/- SE) ALT value from 246 +/- 44.8 U/L to 109.4 +/- 49.1 U/L (p = 0.002) in patients treated with ribavirin. However, there was also significant worsening of interface activity (p = 0.03) and fibrosis (p = 0.02). No significant association was found between ALT values and (i) stage of hepatic fibrosis, (ii) interface activity, (iii) lobular activity and (iv) HCV RNA values. Our results suggest that HCV disease can progress despite a significant decrease in ALT values. ALT values are inadequate markers of the ribavirin monotherapy and can lead to erroneous conclusions of efficacy.

Fulminant hepatic failure associated with propylthiouracil

OBJECTIVE

To report 2 fatal cases of fulminant hepatic failure associated with propylthiouracil treatment against hyperthyroidism.

CASE SUMMARY

Two women, 30 and 32 years old with no previous liver disease, were treated with propylthiouracil against Graves' disease. Both patients developed jaundice after a 4- and 5-month treatment period, respectively. The disease was similar to viral hepatitis, with a progressive course to severe liver dysfunction and death, along with multisystem organ failure despite extensive therapeutic measures. One of the patients was pregnant and subsequently miscarried. Neither patient had a history of alcoholism, drug abuse, blood transfusion, or exposure to hepatitis A, B, or C. Extrahepatic obstruction was ruled out with an abdominal ultrasonogram. Serologic studies and immunologic tests were negative. A submassive necrosis was shown in a postmortem histologic study.

DISCUSSION

Naranjo probability scale criteria applied to both cases confirm the adverse reactions as probable. These cases fit the requirements of drug hepatotoxicity proposed by Hanson and the Council of the International Organization of Medical Sciences. Eight deaths associated to propylthiouracil were found in our review of the medical literature up to December 2000.

CONCLUSIONS

Despite the widespread use of propylthiouracil, fulminant hepatitis with death is exceptionally rare; these 2 cases could be added to the fatal outcomes published to date.

Making sense of liver enzymes, liver function tests, and hepatobiliary disorders at the reference desk

This paper discusses concepts and terminology of some aspects of the laboratory diagnosis of liver (hepatic) disease and biliary tract disease (hepatobiliary disease) as it relates to medical reference work. Details of anatomic, biochemical, and pathologic processes are not discussed. Knowledge of the specific terminology involved in this area may help to ensure a good approach to developing prudent strategies for database searching of the medical literature and therefore is reviewed. MeSH and EMBASE thesauri terms are discussed and textword synonyms are presented that provide tools for thorough searching techniques. Commonly used medical jargon for this area is also explained. Examples of specific search strategies are illustrated.

Quality of life in HCV-infection: lack of association with ALT levels

OBJECTIVES

To examine the impact of HCV infection in an Australian clinic population and identify the relationships between morbidity, psychosocial variables and one clinical indicator of HCV activity, alanine aminotransferase (ALT).

METHOD

Ninety-five untreated HCV-infected patients (21-69 years) in infectious and liver diseases clinics who were all positive for HCV-RNA and had no significant comorbidities or coinfections completed a survey containing the Short Form 36 (SF36), as well as the six-item Social Support Questionnaire (SSQ6), demographic items and questions concerning respondents' perceptions of their mode and duration of infection. Nine volunteers from this group participated in semi-structured qualitative interviews aimed at exploring the social impact of HCV status. These data were compared with serum ALT levels. SF36 scores were compared to population norms and according to participant variables.

RESULTS

Mean SF36 scores were significantly lower, across all modalities, than population norms. SF36 scores differed significantly according to age, sex, mode of infection, alcohol and methadone use, and satisfaction with social support. They did not differ significantly according to perceived or actual ALT level or pattern of ALT activity. Worry about ALT was prevalent (>50%) and this was independent of perceived ALT level.

CONCLUSIONS AND IMPLICATIONS

HCV-infection is associated with significantly reduced quality of life and includes the perception of substantial social discrimination. ALT levels are of limited usefulness in ascertainment of a person's sense of wellbeing and quality of life in HCV-infection. Increased support and information for affected individuals and measures aimed at countering social discrimination are important recommendations of the current study.

Abnormal findings on liver function tests. Interpreting results to narrow the diagnosis and establish a prognosis

Evaluating abnormal liver test results requires careful attention to the corresponding clinical data obtained during history taking and physical examination. Generally, it is helpful to separate liver tests into three categories: tests that assess synthetic function, tests that assess hepatocellular necrosis (hepatocellular enzymes), and tests that assess cholestasis. The clinical setting together with the specific pattern of liver function abnormalities can narrow differential diagnosis and provide a cost-effective approach to assessing patients and identifying those who need liver biopsy.

Inflammation-induced cholestasis

Inflammatory cytokines produced in response to various infectious and non-infectious stimuli are potent inducers of intrahepatic cholestasis (inflammation-induced cholestasis). The cholestatic effect of cytokines results mainly from inhibition of expression and function of hepatocellular transport systems which normally mediate hepatic uptake and biliary excretion of bile salts and various non-bile salt organic anions (e.g. bilirubin). These cytokine effects are reversible and bile secretory function is restored upon disappearance of the inflammatory injury. This review summarizes the clinical, pathophysiological and molecular aspects of inflammation-induced cholestasis.

A prospective study of the causes of notably raised aspartate aminotransferase of liver origin

BACKGROUND AND AIMS

To ascertain the causes of raised aspartate aminotransferase (AST) presumed to be of hepatic origin in two hospitals and the local community served by a centralised biochemistry laboratory.

METHODS

From June 1996 to February 1997 all patients with AST greater than 400 U/l were identified by the biochemistry laboratory; the patients' clinical records were studied to determine the diagnosis, the clinical outcome, and whether the raised AST and its significance had been noted.

RESULTS

A total of 137 patients with a hepatic cause for the raised AST were found. The cause of the raised AST was hepatic ischaemia/hypoxia in 68, pancreatobiliary disease in 33, primary hepatocellular disease in 23, hepatic malignancy in five, and hepatic haematoma in one. In seven patients the diagnosis was unclear. The overall mortality was high (22%) with the highest mortality in the hepatic ischaemia group (37%). The recording and interpretation of the causes of raised AST was poor with only 48% having the correct diagnosis. In 38% the raised AST was apparently not noticed by the attending clinicians.

CONCLUSIONS

The commonest cause of a hepatitis like biochemical picture was hepatic hypoxia (50%) followed by pancreatobiliary disease (24%). Drug induced hepatic necrosis (8.8%) was uncommon and viral hepatitis was rare (3.6%). AST concentrations returned towards normal most rapidly in patients with hepatic hypoxia and calculous biliary obstruction. Hepatitis, viral or otherwise, is an uncommon cause of a typical hepatitic biochemical result in this community.

Safety of <7500 RE (<25000 IU) vitamin A daily in adults with retinitis pigmentosa

BACKGROUND

Vitamin A supplementation is being used successfully to treat some forms of cancer and the degenerative eye disease retinitis pigmentosa. The daily biological need for vitamin A is estimated to be 800 retinol equivalents (RE)/d (2667 IU/d) for adult women and 1000 RE/d (3300 IU/d) for adult men; doses > or = 7500 RE (> or = 25000 IU)/d are considered potentially toxic over the long term.

OBJECTIVE

We assessed the safety in adults of long-term vitamin A supplementation with doses above the daily biological need but <7500 RE (<25000 IU)/d.

DESIGN

Adults aged 18-54 y with retinitis pigmentosa but in generally good health (n = 146) were supplemented with 4500 RE (15000 IU) vitamin A/d for < or = 12 y (group A) and compared with a similar group (n = 149) that received 23 RE (75 IU)/d (trace group). Mean total consumption of vitamin A in group A was 5583 RE (18609 IU)/d (range: 4911-7296 RE/d, or 16369-24318 IU/d) and that in the trace group was 1053 RE (3511 IU)/d (range: 401-3192 RE/d, or 1338-10638 IU/d).

RESULTS

Patients in group A showed an 8% increase in mean serum retinol concentration at 5 y and an 18% increase at 12 y (P < 0.001); no retinol value exceeded the upper normal limit (3.49 micromol/L, or 100 microg/dL). Mean serum retinyl esters were elevated approximately 1.7-fold at 5 y and remained relatively stable thereafter. No clinical symptoms or signs of liver toxicity attributable to vitamin A excess were detected.

CONCLUSIONS

Prolonged daily consumption of <7500 RE (<25000 IU) vitamin A/d can be considered safe in this age group.

Marked increases of aminotransferase levels after cresol ingestion

A 26-year-old woman developed marked increases in levels of aminotransferases about 24 hours after ingestion of 70 mL of 50% cresol. Responding to supportive measures, the patient recovered without any significant complications. Cresol and/or its metabolite may have caused transient hepato-cellular injury in this patient. In cresol poisoning, hepato-cellular injury can manifest even after a 24-hour asymptomatic period.