Review article: herbal and dietary supplement hepatotoxicity

BACKGROUND

Herbal and dietary supplements are commonly used throughout the World. There is a tendency for underreporting their ingestion by patients and the magnitude of their use is underrecognised by Physicians. Herbal hepatotoxicity is not uncommonly encountered, but the precise incidence and manifestations have not been well characterised.

AIMS

To review the epidemiology, presentation and diagnosis of herbal hepatotoxicity. This review will mainly discuss single ingredients and complex mixtures of herbs marketed under a single label.

METHODS

A Medline search was undertaken to identify relevant literature using search terms including 'herbal', 'herbs', 'dietary supplement', 'liver injury', 'hepatitis' and 'hepatotoxicity'. Furthermore, we scanned the reference lists of the primary and review articles to identify publications not retrieved by electronic searches.

RESULTS

The incidence rates of herbal hepatotoxicity are largely unknown. The clinical presentation and severity can be highly variable, ranging from mild hepatitis to acute hepatic failure requiring transplantation. Scoring systems for the causality assessment of drug-induced liver injury may be helpful, but have not been validated for herbal hepatotoxicity. Hepatotoxicity features of commonly used herbal products, such as Ayurvedic and Chinese herbs, black cohosh, chaparral, germander, greater celandine, green tea, Herbalife, Hydroxycut, kava, pennyroyal, pyrrolizidine alkaloids, skullcap, and usnic acid, have been individually reviewed. Furthermore, clinically significant herb-drug interactions are also discussed.

CONCLUSIONS

A number of herbal medicinal products are associated with a spectrum of hepatotoxicity events. Advances in the understanding of the pathogenesis and the risks involved are needed to improve herbal medicine safety.

Delayed presentation of cauda equina syndrome secondary to lumbar disc herniation: functional outcomes and health-related quality of life

OBJECTIVE

Cauda equina syndrome (CES) is a feared complication of lumbar disc herniation. It is generally accepted that CES requires decompression within 6 hours of symptom onset, but this time goal is rarely met, and the relative benefit of delayed decompression on functional status and quality of life (QOL) remains unknown. The study objective was to describe the functional status and quality of life outcomes for patients who undergo delayed surgical decompression for CES.

METHODS

Patients with CES who underwent decompression of a herniated lumbar disc during a 10-year period were assessed at hospital discharge and at least 4 months after the procedure. Evaluation of functional outcomes was based on a previously validated scale and QOL outcomes on the Medical Outcomes Study 36-item Short-Form Health Survey (SF-36) questionnaire.

RESULTS

During the study period, 1100 patients with herniated discs were identified, and 14 underwent surgical decompression for CES. All 14 had had symptoms for more than 38 hours before surgery. Ten patients were available for long-term follow-up. There was a strong correlation between long CES symptom duration and poor functional outcome: of 8 patients with symptoms for less than 10 days before decompression (range, 1.6-7.5 d), all had good functional outcomes. The 2 patients with more prolonged symptoms (10.6 and 14.2 d) had poor outcomes. SF-36 scores demonstrated declines in physical roles (p = 0.03), social function (p = 0.03) and increased pain (p = 0.003) compared with population norms. Correlation between SF-36 domain scores and CES symptom duration failed to achieve statistical significance, perhaps because of small sample size.

CONCLUSIONS

Patients who undergo delayed decompression for CES have increased pain and impaired social and physical function. Longer delays correlate with worse functional outcomes. Beyond 24 hours, decompression delay may be associated with a poorer quality of life but, because of the rarity of CES, the sample size in this study was too small to provide definitive conclusions. Since no patients underwent surgery within 38.4 hours of symptoms, it is not possible to comment on the importance of emergent decompression in early presenters.

Standardization of terminology of virological response in the treatment of chronic hepatitis C: panel recommendations

The treatment paradigm for hepatitis C virus (HCV) infection is at a critical point in its evolution. The addition of a protease inhibitor to peginterferon plus ribavirin has become the new standard-of-care treatment for most patients. Data from clinical trials of new antivirals have been difficult to interpret and compare, partly because of heterogeneity in trial design, and partly because of inconsistencies in terminology used to define viral responses and the populations evaluated. Present definitions of viral responses for treatment with peginterferon and ribavirin are insufficient for novel treatment paradigms. Further, categorization of prior patient treatment experience in clinical trials, particularly of nonresponders to prior therapy, is inconsistent. Existing terms and definitions must be updated, standardized and/or redefined for easier interpretation of data and effective communication among clinicians. A panel of experts in HCV infection treatment met on 3 December 2009. Goals of the panel were to evaluate terms and definitions used traditionally in treatment with peginterferon and ribavirin, to refine and clarify definitions of existing terms that have varying meanings and to propose new terms and definitions appropriate for novel treatment paradigms emerging with development of new agents. A number of recommendations were accepted unanimously by the panel. Adoption of these terms would improve communication among investigators, enhance comparability among clinical trials, facilitate development of therapeutic guidelines and provide a standardized terminology for use in clinical practice.

Presurgical management of a child with missing lower lip using a new design of fixed lower tongue crib

Missing of any perioral structure can result in imbalance of muscular forces leading to loss of structure and function along with esthetics especially in a growing individual and can result in permanent damage. Rehabilitation of such children is a challenge and requires an integrated multidisciplinary approach not only to correct the defect, but also to ensure normal development with minimal handicap. Here is a case report of a 10-year-old child with missing lower lip due to childhood infection and its presurgical management using a new design of fixed lower tongue crib used to limit tongue pressure, improve tongue position, and facilitate lower incisor retraction. A new clinical experience for lower lip missing cases in children are added, as these cases are rare.

Response to tenofovir monotherapy in chronic hepatitis B patients with prior suboptimal response to entecavir

Both entecavir (ETV) and tenofovir (TDF) are potent antiviral agents for hepatitis B virus (HBV). Suboptimal response (SOR) following antiviral therapy is associated with an increased risk of subsequent treatment failure and viral resistance. It remains unclear whether switching to TDF is a reasonable approach in patients with SOR to ETV treatment. This study was aimed to determine how HBV patients with SOR to ETV respond to TDF monotherapy. Data of patients with SOR to ETV (failure to achieve >1 log(10) HBV-DNA reduction during the last 24 weeks of ETV treatment) who were switched to TDF monotherapy during 2005 and 2010 were reviewed. Treatment adherence was assessed by pill-count. Fourteen patients (2.9%) were identified from a total cohort of 482 ETV-treated patients. All 14 patients were Chinese and were infected with HBV genotype C (71%) or B (29%). Nine patients were men, and the median age was 41.5 years (19-64). Twelve were treatment naïve (one lamivudine- and one peginterferon-experienced patient); 85.7% were HBeAg positive. The median baseline HBV-DNA was 7.55 (5.30-9.40) log(10) copies/mL, and 57% had abnormal serum alanine aminotransferase (ALT) levels. Precore and/or basal core promoter mutations were detected in four patients, whereas no genotypic resistance was detected at baseline and before switching to TDF. The median duration of ETV treatment was 64.5 (26-126) weeks. The median HBV-DNA at the time of switching to TDF was 3.69 (3.00-4.90) log(10) copies/mL. The median HBV-DNA reduction from baseline and during the last 6-month observation period prior to switching to TDF was 4.04 (0.51-6.06) log(10) and 0.43 (-0.09-1.13) log(10) copies/mL, respectively. After the switching to TDF, all 14 patients (100%) achieved undetectable HBV-DNA and ALT normalization within a median duration of 30 weeks. In 12 patients who were HBeAg positive, HBeAg seroconversion was observed in two patients after TDF treatment of 75- and 84-weeks duration. There was no virological breakthrough observed after switching to TDF with a median follow-up period of 50 (24-160) weeks. TDF treatment was safe and well tolerated. In conclusion, suboptimal response to ETV is rare (approximately 3%). TDF monotherapy is safe and very effective in the management of HBV patients with SOR to ETV.

GHB-Induced Cognitive Deficits During Adolescence and the Role of NMDA Receptor

We have earlier reported that γ-hydroxybutyric acid (GHB) disrupts the acquisition of spatial learning and memory in adolescent rats. GHB is known to interact with several neurotransmitter systems that have been implicated in cognitive functioning. The N-methyl-D-aspartate receptor (NR) -type of glutamate receptor is considered to be an important target for spatial learning and memory. Molecular mechanisms governing the neuroadptations following repeated GHB treatment in adolecent rats remain unknown. We examined the role of NMDA receptor in adolescent GHB-induced cognitive deficit. Adolescent rats were administered with GHB on 6 consecutive days, and surface-expressed NMDA receptor subunits levels were measured. GHB significantly decreased NR1 levels in the frontal cortex. Adolescent GHB also significantly reduced cortical NR2A subunit levels. Our findings support the hypothesis that adolescent GHB-induced cogntive deficits are associated with neuroadaptations in glutamatergic transmission, particulaly NR functioning in the frontal cortex.

Waitlist survival of patients with primary sclerosing cholangitis in the model for end-stage liver disease era

The ability of the Model for End-Stage Liver Disease (MELD) score to capture the urgency of transplantation may not be generalizable to patients with primary sclerosing cholangitis (PSC) because these patients face unique risks of death or removal from the liver transplant waitlist due to disease-specific complications (eg, repeated bouts of bacterial cholangitis and cholangiocarcinoma). We constructed Cox regression models to determine whether disease-based differences exist in waitlist mortality before liver transplantation. We compared the times to death or withdrawal from the waitlist due to clinical deterioration among patients with or without PSC in the United States after the implementation of the MELD allocation score. Over an 8-year period, 14,073 non-PSC patients (20.5%) and 432 PSC patients (13.6%) died or were removed (P < 0.0001). The adjusted hazard ratio (HR) for PSC was 0.72 [95% confidence interval (CI) = 0.66-0.79], which indicated that these patients had a lower time-dependent risk of death or removal from the waitlist in comparison with patients without PSC. This difference was explained in part by the groups' different probabilities of portal hypertension complications at listing because adjustments for these intermediate endpoints moved the HR closer to the null (0.84, 95% CI = 0.74-0.97). In comparison with patients with other forms of end-stage liver disease, patients with PSC are less likely to die or be removed from the waitlist because of clinical deterioration; therefore, the prevailing practice in some centers and regions of preemptively referring PSC patients for living donor transplantation or exception points should be reconsidered.

Clinical features and natural history of hepatocellular adenomas: the impact of obesity

BACKGROUND

Hepatocellular adenoma is a benign tumour associated with bleeding and malignant transformation. Obesity has been linked to hepatic tumourigenesis.

AIM

To evaluate the presentation of hepatocellular adenoma in obesity, and the impact of obesity on the clinical course.

METHODS

Records of 60 consecutive patients (between 2005 and 2010) with a diagnosis of hepatocellular adenoma from a single tertiary centre were analysed.

RESULTS

Fifty six of 60 patients were women, median age was 36years, 75% had history of contraceptive use, 18% were overweight and 55% were obese (BMI ≥30kg/m(2) ). Majority (63%) were asymptomatic; seven patients presented with bleeding. Single (28%) and multiple adenomas (72%) were encountered; size ranged from 1 to 19.7cm. Obesity was more often associated with multiple adenomas (85% vs. 48%, P=0.005), bilobar distribution (67% vs. 33%, P=0.01), lower serum albumin (P=0.007) and co-morbidities of fatty liver (P=0.006), diabetes (P=0.003), hypertension (P=0.006) and dyslipidemia (P=0.03). During median follow-up of 2.6years, there were no instances of bleeding, malignant transformation or death. Thirty four patients underwent therapeutic intervention (17 surgical resection, nine transarterial embolization and eight both interventions sequentially). The rate of complete resection of adenoma(s) was significantly lower in obese patients (8% vs. 69%, P=0.004). In the 26 patients without intervention, tumour size progression was more frequently observed in obese patients (33% vs. 0%, P=0.05). Three of 15 obese patients (20%) lost ≥5% body weight and there was no progression in the liver lesions.

CONCLUSIONS

Obesity and features of metabolic syndrome were frequently observed in hepatocellular adenoma. Multiple and bilobar adenomas were more frequent in obese patients. Among patients who were conservatively managed, tumour progression was more often associated with obesity.

Rhabdomyolysis with acute renal failure triggered by the seasonal flu vaccination in a patient taking simvastatin

A man in his 70s presented with bilateral, painful legs and feeling generally unwell following the seasonal flu vaccination. The patient had a background of B cell lymphoma in partial remission. His current medications included simvastatin. Initial investigations revealed rhabdomyolysis and acute renal failure. He was admitted to critical care for renal replacement treatment. Other causes of rhabdomyolysis were excluded and expert opinion agreed that the most likely cause was the influenza vaccination with the concurrent use of simvastatin. The patient's renal function gradually normalised and after several months the patient has regained full power in his legs.