Treatment of amatoxin poisoning: 20-year retrospective analysis

Integrating dietary supplements into cancer care

Many studies confirm that a majority of patients undergoing cancer therapy use self-selected forms of complementary therapies, mainly dietary supplements. Unfortunately, patients often do not report their use of supplements to their providers. The failure of physicians to communicate effectively with patients on this use may result in a loss of trust within the therapeutic relationship and in the selection by patients of harmful, useless, or ineffective and costly nonconventional therapies when effective integrative interventions may exist. Poor communication may also lead to diminishment of patient autonomy and self-efficacy and thereby interfere with the healing response. To be open to the patient's perspective, and sensitive to his or her need for autonomy and empowerment, physicians may need a shift in their own perspectives. Perhaps the optimal approach is to discuss both the facts and the uncertainty with the patient, in order to reach a mutually informed decision. Today's informed patients truly value physicians who appreciate them as equal participants in making their own health care choices. To reach a mutually informed decision about the use of these supplements, the Clinical Practice Committee of The Society of Integrative Oncology undertook the challenge of providing basic information to physicians who wish to discuss these issues with their patients. A list of leading supplements that have the best suggestions of benefit was constructed by leading researchers and clinicians who have experience in using these supplements. This list includes curcumin, glutamine, vitamin D, Maitake mushrooms, fish oil, green tea, milk thistle, Astragalus, melatonin, and probiotics. The list includes basic information on each supplement, such as evidence on effectiveness and clinical trials, adverse effects, and interactions with medications. The information was constructed to provide an up-to-date base of knowledge, so that physicians and other health care providers would be aware of the supplements and be able to discuss realistic expectations and potential benefits and risks.

Legalon® SIL: the antidote of choice in patients with acute hepatotoxicity from amatoxin poisoning

More than 90% of all fatal mushroom poisonings worldwide are due to amatoxin containing species that grow abundantly in Europe, South Asia, and the Indian subcontinent. Many cases have also been reported in North America. Initial symptoms of abdominal cramps, vomiting, and a severe cholera-like diarrhea generally do not manifest until at least six to eight hours following ingestion and can be followed by renal and hepatic failure. Outcomes range from complete recovery to fulminant organ failure and death which can sometimes be averted by liver transplant. There are no controlled clinical studies available due to ethical reasons, but uncontrolled trials and case reports describe successful treatment with intravenous silibinin (Legalon® SIL). In nearly 1,500 documented cases, the overall mortality in patients treated with Legalon® SIL is less than 10% in comparison to more than 20% when using penicillin or a combination of silibinin and penicillin. Silibinin, a proven antioxidative and anti-inflammatory acting flavonolignan isolated from milk thistle extracts, has been shown to interact with specific hepatic transport proteins blocking cellular amatoxin re-uptake and thus interrupting enterohepatic circulation of the toxin. The addition of intravenous silibinin to aggressive intravenous fluid management serves to arrest and allow reversal of the manifestation of fulminant hepatic failure, even in severely poisoned patients. These findings together with the available clinical experience justify the use of silibinin as Legalon® SIL in Amanita poisoning cases.

Amatoxins in wood-rotting Galerina marginata

Amatoxins, bicyclic octapeptide derivatives responsible for severe hepatic failure, are present in several Basidiomycota species belonging to four genera, i.e. Amanita, Conocybe, Galerina and Lepiota. DNA studies for G. autumnalis, G. marginata, G. oregonensis, G. unicolor and G. venenata (section Naucoriopsis) determined that these species are the same, supporting the concept of Galerina marginata complex. These mostly lignicolous species are designated as white-rot fungi having a broad host range and capable of degrading both hardwoods and softwoods. Twenty-seven G. marginata basidiomes taken from different sites and hosts (three sets) as well as 17 A. phalloides specimens (three sets) were collected in French locations. The 44 basidiomes were examined for amatoxins and phallotoxins using high-performance liquid chromatography. Toxinological data for the wood-rotting G. marginata and the ectomycorrhizal A. phalloides species were compared and statistically analyzed. The acidic and neutral phallotoxins were not detected in any G. marginata specimen, whereas the acidic (β-Ama) and neutral (α-Ama and γ-Ama) amanitins were found in all basidiomes from either Angiosperms or Gymnosperms hosts. The G. marginata amatoxin content varied from 78.17 to 243.61 μg.mg(-1) of fresh weight and was elevated significantly in one set out of three. The amanitin amounts from certain Galerina specimens were higher than those from some A. phalloides basidiomes. Relationship between the amanitin distribution and the chemical composition of substrate was underlined and statistically validated for the white-rot G. marginata. Changes in nutritional components from decayed host due to enzymatic systems and genetic factors as well as environmental conditions seem to play a determinant role in the amanitin profile. Variability noticed in the amanitin distribution for the white-rot G. marginata basidiomes was not observed for the ectomycorrhizal A. phalloides specimens.

Silybum marianum (milk thistle) in the management and prevention of hepatotoxicity in a patient undergoing reinduction therapy for acute myelogenous leukemia

Hepatotoxicity has been observed with several chemotherapy agents and combination regimens. Conventional treatment methods often include supportive care or observation. We report a case of a patient with noted transaminitis presumed secondary to chemotherapy, which did not resolve with supportive care but was shown to respond to milk thistle. The patient had an immediate decrease in liver function tests and showed decreased elevation in levels upon treatment with subsequent chemotherapy regimens. This case demonstrates the potential efficacy of milk thistle as a unique hepatoprotective agent.

An Update on Drug-induced Liver Injury

Idiosyncratic drug-induced liver injury (DILI) is an important cause of morbidity and mortality following drugs taken in therapeutic doses. Hepatotoxicity is a leading cause of attrition in drug development, or withdrawal or restricted use after marketing. No age is exempt although adults and the elderly are at increased risk. DILI spans the entire spectrum ranging from asymptomatic elevation in transaminases to severe disease such as acute hepatitis leading to acute liver failure. The liver specific Roussel Uclaf Causality Assessment Method is the most validated and extensively used for determining the likelihood that an implicated drug caused DILI. Asymptomatic elevation in liver tests must be differentiated from adaptation. Drugs producing DILI have a signature pattern although no single pattern is characteristic. Antimicrobial and central nervous system agents including antiepileptic drugs are the leading causes of DILI worldwide. In the absence of a diagnostic test or a biomarker, the diagnosis rests on the evidence of absence of competing causes such as acute viral hepatitis, autoimmune hepatitis and others. Recent studies show that antituberculosis drugs given for active or latent disease are still a major cause of drug-induced liver injury in India and the West respectively. Presence of jaundice signifies a severe disease and entails a worse outcome. The pathogenesis is unclear and is due to a mix of host, drug metabolite and environmental factors. Research has evolved from incriminating candidate genes to genome wide analysis studies. Immediate cessation of the drug is key to prevent or minimize progressive damage. Treatment is largely supportive. N-acetylcysteine is the antidote for paracetamol toxicity. Carnitine has been tried in valproate injury whereas steroids and ursodeoxycholic acid may be used in DILI associated with hypersensitivity or cholestatic features respectively. This article provides an overview of the epidemiology, the patterns of hepatotoxicity, the pathogenesis and associated risk factors besides its clinical management.

A rare case of amatoxin poisoning in the state of Texas

Ingestion of mushrooms from the genus Amanita can present detrimental consequences to the human body. The mushroom is frequently found in the coastal Pacific Northwest, Pennsylvania, New Jersey, and Ohio. Amanitin, one of the two distinct toxins isolated from the Amanita mushroom, is responsible for the majority of symptoms and signs seen with mushroom poisoning. Clinically, ingestion of these mushrooms can result in a wide range of clinical symptoms including nausea, vomiting, crampy abdominal pain, and diarrhea. There have been several case reports of patients who developed severe hepatic failure that required liver transplantation. Thus, it is important to recognize the symptoms early and treat the patients with the available agents including multidose activated charcoal, N-acetylcysteine, penicillin G, and Silybum. Through an extensive literature search, we found no published literature on amatoxin poisoning in the state of Texas. With new cases of amatoxin poisoning emerging in the state, it is important for healthcare providers and workers to have a better awareness and early recognition of the detrimental effects of Amanita species poisoning and to be educated to provide the proper care for this group of patients.

Mushroom poisoning: a study on circumstances of exposure and patterns of toxicity

BACKGROUND

Picking wild mushrooms is a popular pastime in Switzerland. Correct identification of the species is difficult for laypersons. Ingestion of toxic mushrooms may result in serious toxicity, including death. The aim of the study is to analyze and describe the circumstances of exposure to mushrooms, and to define the clinical relevance of mushroom poisoning for humans in Central Europe.

MATERIALS AND METHODS

We performed a retrospective case study and analyzed all inquiries concerning human exposures to mushrooms (n = 5638, 1.2% of all inquiries) which were reported to the Swiss Toxicological Information Centre between January 1995 and December 2009.

RESULTS

The most frequent reason for contacting the poison center in cases of adult exposure was toxicity resulting from edible species. Pediatric exposure predominantly occurred from mushrooms found around the home. Severe symptoms have not only been observed after ingestion of non-amatoxin-containing toxic mushrooms, i.e. Boletus sp. and Cortinarius sp., but also after meals of edible species. The mortality of confirmed amatoxin poisonings was high (5/32) compared to other reports.

CONCLUSIONS

Inquiries regarding mushroom poisoning were a relatively infrequent reason for contacting the poison center. Nevertheless, accidental ingestion of toxic mushrooms can be responsible for severe or fatal poisonings. Although pediatric exposure to mushrooms found around the home has not led to serious toxicity in this study, prevention of exposure is warranted. Inspection of wild mushrooms by a certified mushroom expert or a mycologist seems to be a safe procedure which should be recommended.

Amatoxin poisoning: case reports and review of current therapies

BACKGROUND

Diagnosis and management of Amanita mushroom poisoning is a challenging problem for physicians across the United States. With 5902 mushroom exposures and two resultant deaths directly linked to Amanita ingestion in 2009, it is difficult for physicians to determine which patients are at risk for lethal toxicity. Identification of amatoxin poisoning can prove to be difficult due to delay in onset of symptoms and difficulty with identification of mushrooms. Consequently, it is difficult for the Emergency Physician to determine proper disposition. Further, treatment options are controversial.

OBJECTIVES

To review current data to help health care providers effectively identify and treat potentially deadly Amanita mushroom ingestions.

CASE REPORTS

We present two cases of Amanita mushroom ingestion in the northeastern United States treated with N-acetylcysteine, high-dose penicillin, cimetidine, and silibinin, a semi-purified fraction of milk thistle-derived silymarin, as part of their treatment regimen. The mushroom species was identified by a consultant as Amanita Ocreata.

CONCLUSIONS

We present the successful treatment of 2 patients who ingested what we believe to be an Amanita species never before identified in the northeastern United States.

[Acute hepatic failure after ingestion of mushrooms]

This report is about a married couple who were admitted to hospital suffering from gastrointestinal complaints after eating mushrooms. With the suspicion of poisoning with Amanita phalloides treatment started with elimination of the toxins, symptomatic therapy and specific therapy with silibinin. After quantitative determination of the Amanita toxins the patients were immediately transferred to a university hospital.Poisoning by the death cap mushroom is responsible for acute hepatic and often also renal failure and is accompanied by a high mortality. Clinical symptoms follow a three-phase course with gastrointestinal complaints, an asymptomatic interval and finally the hepatorenal phase. Even in suspected cases of intoxication, treatment should be started by antidote therapy with silibinin.

Approach to mushroom intoxication and treatment: can we decrease mortality?

BACKGROUND

Mushroom is widely consumed in Turkey because it is inexpensive and widely available. Intoxication with mushroom is a common health problem in Turkey with a high mortality rate.

AIM

To identify the outcome of patients with wild mushroom intoxication who were diagnosed based on systematic criteria and had received a comprehensive treatment.

METHODS

Seventy-seven patients admitted to the Emergency Department of our hospital with mushroom intoxication were retrospectively evaluated. The patients were administered a combined treatment of gastric lavage, activated charcoal, penicillin G, N-acetyl cysteine, silybin and hemofiltration. Demographic, clinical and laboratory data of patients and the outcomes of the treatment modality were recorded.

RESULTS

A total of 77 patients, 46 (59.7%) females and 31 (40.3%) males were evaluated in the study. The mean age of the patients was 41.94 ± 15.40 years. They presented with nausea and vomiting within 4 to 48 hours. Sixteen patients (20.7%) had abdominal pain, six patients had (7.7%) diarrhea and five patients (6.5%) had jaundice. Seven patients (9%) developed acute liver failure and were referred to intensive care units. Five of these patients recovered without any liver transplantation; one patient had cadaveric liver transplantation but died in the early period after the transplantation and one patient died while waiting for transplantation. The rest of the patients were followed by us and they all have recovered.

CONCLUSIONS

Our data indicate that clinical diagnosis based on systematic criteria and a comprehensive treatment regimen may be effective in decreasing the mortality in mushroom intoxication.

Acute Liver Failure Caused by Amanita phalloides Poisoning

Mushroom poisoning is a relatively rare cause of acute liver failure (ALF). The present paper analyzes the pathogenesis, clinical features, prognostic indicators, and therapeutic strategies of ALF secondary to ingestion of Amanita phalloides, which represents the most common and deadly cause of mushroom poisoning. Liver damage from Amanita phalloides is related to the amanitins, powerful toxins that inhibit RNA polymerase II resulting in a deficient protein synthesis and cell necrosis. After an asymptomatic lag phase, the clinical picture is characterized by gastrointestinal symptoms, followed by the liver and kidney involvement. Amatoxin poisoning may progress into ALF and eventually death if liver transplantation is not performed. The mortality rate after Amanita phalloides poisoning ranges from 10 to 20%. The management of amatoxin poisoning consists of preliminary medical care, supportive measures, detoxification therapies, and orthotopic liver transplantation. The clinical efficacy of any modality of treatment is difficult to demonstrate since randomized, controlled clinical trials have not been reported. The use of extracorporeal liver assist devices as well as auxiliary liver transplantation may represent additional therapeutic options.

Toxicology in the ICU: part 3: natural toxins

This is the third article of a three-part series that reviews the care of poisoned patients in the ICU. This article focuses on natural toxins, such as heavy metals and those produced by plants, mushrooms, arthropods, and snakes. The first article discussed the general approach to the patient, including laboratory testing; the second article focused on specific toxic agents, grouped into categories.

Ribosomal biosynthesis of α-amanitin in Galerina marginata

Amatoxins, including α-amanitin, are bicyclic octapeptides found in mushrooms (Agaricomycetes, Agaricales) of certain species in the genera Amanita, Galerina, Lepiota, and Conocybe. Amatoxins and the chemically similar phallotoxins are synthesized on ribosomes in Amanita bisporigera, Amanita phalloides, and Amanita ocreata. In order to determine if amatoxins are synthesized by a similar mechanism in another, distantly related mushroom, we obtained genome survey sequence data from a monokaryotic isolate of Galerinamarginata, which produces α-amanitin. The genome of G. marginata contains two copies of the α-amanitin gene (GmAMA1-1 and GmAMA1-2). The α-amanitin proprotein sequences of G. marginata (35 amino acids) are highly divergent from AMA1 of A. bisporigera except for the toxin region itself (IWGIGCNP in single-letter amino acid code) and the amino acids immediately upstream (N[A/S]TRLP). G. marginata does not contain any related toxin-encoding sequences besides GmAMA1-1 and GmAMA1-2. DNA from two other α-amanitin-producing isolates of Galerina (G. badipes and G. venenata) hybridized to GmAMA1, whereas DNA from the toxin non-producing species Galerinahybrida did not. Expression of the GmAMA1 genes was induced by growth on low carbon. RNASeq evidence indicates that both copies of GmAMA1 are expressed approximately equally. A prolyl oligopeptidase (POP) is strongly implicated in processing of the cyclic peptide toxins of A. bisporigera and Conocybe apala. G. marginata has two predicted POP genes; one, like AbPOPB of A. bisporigera, is present only in the toxin-producing isolates of Galerina and the other, like AbPOPA of A. bisporigera, is present in all species. Our results indicate that G.marginata biosynthesizes amatoxins on ribosomes by a pathway similar to Amanita species, involving a genetically encoded proprotein of 35 amino acids that is post-translationally processed by a POP. However, due to the high degree of divergence, the evolutionary relationship between AMA1 in the genera Amanita and Galerina is unclear.

Assessment of emergency liver transplantation criteria in acute liver failure due to Amanita phalloides

BACKGROUND AND AIMS

The emergency liver transplantation criteria for acute liver failure (ALF) due to Amanita phalloides (A. phalloides) intoxication are not consensual. The aims of this study were to evaluate the clinical outcomes, and to assess the accuracy of the current and specific criteria for emergency liver transplantation in predicting fatal outcome in ALF induced by A. phalloides.

METHODS

Ten patients admitted with ALF induced by A. phalloides in a Gastroenterology Intensive Care Unit were studied. Indications for liver transplant were based on Clichy and/or King's College criteria. Specific criteria of Ganzert and Escudié were tested retrospectively.

RESULTS

A. phalloides intoxication represented 11.6% of all admissions for ALF. Patients were admitted at a mean time of 60 ± 20.4 h after ingestion. Eight patients met the Clichy and/or King's College criteria for emergency liver transplantation, seven of these patients were listed for transplant and only six patients were transplanted. Four (40%) patients died in a mean time of 4.8 ± 0.74 days after ingestion. When applied retrospectively, Escudié's criteria showed 100% of accuracy for predicting fatal outcome, whereas, King's College, Clichy's and Ganzert's criteria had an accuracy of 90, 80 and 70%, respectively. A prothrombin index of less than 10% at day 3 after ingestion showed a positive predictive value of 100% and a negative predictive value of 60%.

CONCLUSION

Escudié's criteria show the best accuracy for emergency liver transplant in ALF induced by A. phalloides. The assessment of these criteria at day 3 after ingestion shows a maximum positive predictive value, although with a decline in its negative predictive value.

Clinical features and outcome of patients with amatoxin-containing mushroom poisoning

OBJECTIVE. We aimed to determine clinical and laboratory findings that were different between those patients who died and those who survived and to look for factors associated with the mortality in amatoxin-containing mushroom poisoning. METHODS. The mushroom poisoning patients who were admitted to our clinic between 1996 and 2009 were retrospectively evaluated. The diagnosis was based on a history of mushroom ingestion, clinical picture and the presence of serum alpha-amanitin. Patients were divided into two groups as the survival group and the fatality group. Clinical and laboratory findings were compared between the two groups. Relation between variables and clinical outcome was analyzed. RESULTS. A total of 144 amatoxin poisoning patients were included in this study. Patients who died were more likely to have demonstrated low mean arterial pressure, encephalopathy, mucosal hemorrhage, oliguria-anuria, hypoglycemia, and thrombocytopenia during the hospitalization. Low sodium values and high urea, AST, ALT, total bilirubin, LDH, prothrombin time, international normalized ratio, and activated partial thromboplastin time values were associated with increased likelihood of mortality. Nineteen patients developed acute renal failure. Fourteen patients developed acute hepatic failure. All the 14 patients who died developed acute hepatic failure. The mortality rate was 9.7%. CONCLUSIONS. The factors associated with mortality determined in this retrospective study may be helpful for clinical outcome assessment and monitoring of patients with amatoxin-containing mushroom poisoning.

Comparative antidotal efficacy of benzylpenicillin, ceftazidime and rifamycin in cultured human hepatocytes intoxicated with α-amanitin

The most often used antidote to treat poisoning caused by amanitin-containing mushrooms is benzylpenicillin (BPCN). However, a very few reports suggest that other antibiotics such as ceftazidime (CEFT) and rifamycin SV (RIFSV) show better antidote activity against amanitins than BPCN. Given this, there is an ongoing debate as which of three antidotes is optimal for treatment of such poisonings. In this study, the efficacy of BPCN was compared with those of CEFT and RIFSV in human hepatocyte model. The functional integrity and viability of cultured hepatocytes was evaluated using the MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide] assay and by measurements of lactic dehydrogenase (LDH) activity. In the first experimental layout, hepatocytes were simultaneously exposed to α-AMA and tested antidotes, while in the second layout, the cells were exposed for the first 12 h to α-AMA only, and then, the medium containing α-AMA was exchanged to culture medium containing both α-AMA and the antidotes tested. The results demonstrated that simultaneous administration of α-AMA and each of tested antidotes (BPCN, CEFT, RIFSV) effectively protected human hepatocytes; however, in the group dosed with BPCN, the highest hepatocyte viability was observed. In cell cultures from experimental layout II, all tested antidotes were ineffective, which indicates that after the critical dose of α-AMA had been taken up by hepatocytes, further suppression of this process does not protect the cells against injury. Thus, 12 h of exposure of incubated hepatocytes to α-AMA is a sufficient time for such a cellular uptake of a critical dose of this toxin. In summary, it can be concluded that easily accessible and low-cost BPCN should be widely used as an antidote against amanitins. However, the key to successful therapy is a quick implementation of an antidote in order to protect as large as possible portion of the liver parenchyma against the devastating uptake of a critical dose of amanitins.

Silybin and the liver: From basic research to clinical practice

Herbal products are increasingly used, mainly in chronic liver disease. Extracts of milk thistle, Silymarin and silybin, are the most prescribed natural compounds, with different indications, but with no definitive results in terms of clinical efficacy. This review analyzes the available studies on the effects of the purified product silybin, both as a free and a conjugated molecule, on liver cells or on experimentally induced liver damage, and in patients with liver disease. We searched PUBMED for articles pertaining to the in vitro and in vivo effects of silybin, its antifibrotic, anti-inflammatory, and antioxidant properties, as well as its metabolic effects, combined with the authors’ own knowledge of the literature. Results indicate that the bioavailability of silybin phytosome is higher than that of silymarin and is less influenced by liver damage; silybin does not show significant interactions with other drugs and at doses < 10 g/d has no significant side effects. Experimental studies have clearly demonstrated the antifibrotic, antioxidant and metabolic effects of silybin; previous human studies were insufficient for confirming the clinical efficacy in chronic liver disease, while ongoing clinical trials are promising. On the basis of literature data, silybin seems a promising drug for chronic liver disease.

Amanita phalloides poisoning

A Vietnamese family living in the Pacific Northwest harvested several wild mushrooms grown in their front lawn. All three in the family suffered from delayed GI symptoms starting approximately 12 h after ingestion. One patient died and two developed hepatic injury. We provide photography and describe common characteristics of Amanita phalloides mushroom.

Development of a DNA-based macroarray for the detection and identification of Amanita species

A DNA-based macroarray was designed to quickly and accurately identify certain Amanita mushroom specimens at the species level. The macroarray included probes for Amanita phalloides and Amanita ocreata, toxic species responsible for most mushroom poisonings, and Amanita lanei and Amanita velosa, edible species sometimes confused with toxic species, based on sequences of the highly variable internal transcribed spacer (ITS) region of rDNA. A cryptic species related to A. ocreata and one related to A. lanei, identifiable by ITS sequences, were also included. Specific multiple oligonucleotide probes were spotted onto nylon membranes and the optimal hybridization temperatures were determined. The Amanita DNA array was highly specific, sensitive (0.5 ng DNA/μL and higher were detected), and reproducible. In two case studies, the method proved useful when only small amounts of mushroom tissue remained after a suspected poisoning. An identification could be completed in 12 h.

Amanita bisporigera-Induced Hepatic Failure: A Fatal Case of Mushroom Ingestion

Wild mushroom poisoning from the genus Amanita is a medical emergency, with Amanita phalloides being the most common offender. Patients may complain of nausea, vomiting, diarrhea and/or abdominal pain. If not aggressively treated, fulminant hepatic failure may develop within several days of ingestion. In this case report, a patient poisoned with Amanita bisporigera is described, along with the typical clinical presentation, patient outcomes, and treatment options for dealing with an Amanita mushroom poisoning.

alpha-Amanitin induced apoptosis in primary cultured dog hepatocytes

Amatoxin poisoning is caused by mushroom species belonging to the genera Amanita, Galerina and Lepiota with the majority of lethal mushroom exposures attributable to Amanita phalloides. High mortality rate in intoxications with these mushrooms is principally a result of the acute liver failure following significant hepatocyte damage due to hepatocellular uptake of amatoxins. A wide variety of amatoxins have been isolated; however, alpha-amanitin (alpha-AMA) appears to be the primary toxin. Studies in vitro and in vivo suggest that alpha-AMA does not only cause hepatocyte necrosis, but also may lead to apoptotic cell death. The objective of this study was to evaluate the complex hepatocyte apoptosis in alpha-AMA cytotoxicity. All experiments were performed on primary cultured canine hepatocytes. The cells were incubated for 12 h with alpha-AMA at a final concentration of 1, 5, 10 and 20 microM. Viability test (MTT assay), apoptosis evaluation (TUNEL reaction, detection of DNA laddering and electron microscopy) were performed at 6 and 12 h of exposure to alpha-AMA. There was a clear correlation between hepatocyte viability, concentration of alpha-AMA and time of exposure to this toxin. The decline in cultured dog hepatocyte viability during the exposure to alpha-AMA is most likely preceded by enhanced cellular apoptosis. Our results demonstrate that apoptosis might contribute to pathogenesis of the severe liver injury in the course of amanitin intoxication, particularly during the early phase of poisoning.

Chemotherapeutic activity of silymarin combined with doxorubicin or paclitaxel in sensitive and multidrug-resistant colon cancer cells

PURPOSE

The milk thistle extract silymarin, alone or in combined chemotherapy, is now under investigation in anticancer research, with particular interest for its possible employ in the treatment of chemoresistant tumours. So far, the consequences of a silymarin pre-treatment have not been thoroughly investigated. We studied whether silymarin pre-treatment synergized with chemotherapy, exploring the dose-dependence of the interaction in sensitive and multidrug-resistant cells.

METHODS

We studied cell cycle perturbations induced by silymarin in two colon carcinoma cell lines, LoVo and the multidrug-resistant isogenic LoVo/DX. Synergism/additivity/antagonism of silymarin-doxorubicin silymarin-paclitaxel combined treatments were evaluated by isobologram/combination index analysis, in the whole spectrum of active and sub-active concentrations of all drugs. The mechanisms of silymarin interaction with the other drugs were investigated by measuring drug uptake and cell cycle perturbations.

RESULTS

Silymarin had similar antiproliferative activity against both cell lines. Pre-treatment with low silymarin concentrations synergised with both doxorubicin and paclitaxel in LoVo but not in LoVo/DX. Higher silymarin concentrations were additive with doxorubicin and paclitaxel in both cell lines. Silymarin favourably interfered with uptake and cell cycle effects of the chemotherapeutics in LoVo but not in LoVo/DX.

CONCLUSION

These findings confirm activity of silymarin against colon carcinoma, including multidrug-resistant types, at relatively high but clinically achievable concentrations. In view of its low toxicity, two schedules based on low- and high-dose silymarin pre-treatment might offer a valuable option for combined treatment.

Influence of commonly used clinical antidotes on antioxidant systems in human hepatocyte culture intoxicated with alpha-amanitin

α-Amanitin (α-AMA) is the main toxin of Amanita phalloides and its subspecies (A. virosa and A. verna). The primary mechanism of α-AMA toxicity is associated with protein synthesis blocking in hepatocytes. Additionally, α-AMA exhibits prooxidant properties that may contribute to its severe hepatotoxicity. The aim of the present study was to assess the effect of α-AMA on lipid peroxidation and the activities of superoxide dismutase (SOD) and catalase (CAT) in human hepatocyte culture. The effects of benzylpenicillin (BPCN), N-acetyl-L-cysteine (ACC), and silibinin (SIL) on SOD and CAT activities and on lipid peroxidation in human hepatocyte culture intoxicated with α-AMA were also examined. In human hepatocyte culture, 48-hour exposure to α-AMA at a 2-μM concentration caused an increase in SOD activity, a reduction of CAT activity, and a significant increase in lipid peroxidation. Changes in SOD and CAT activity caused by α-AMA could probably enhance lipid peroxidation by increased generation of hydrogen peroxide combined with reduced detoxification of that oxygen radical. The addition of antidotes (ACC or SIL) to the culture medium provided more effective protection against lipid peroxidation in human hepatocytes intoxicated with α-AMA than the addition of BPCN, possessing no antioxidant properties.

Amatoxin poisoning treatment decision-making: pharmaco-therapeutic clinical strategy assessment using multidimensional multivariate statistic analysis

Ninety percent of fatal higher fungus poisoning is due to amatoxin-containing mushroom species. In addition to absence of antidote, no chemotherapeutic consensus was reported. The aim of the present study is to perform a retrospective multidimensional multivariate statistic analysis of 2110 amatoxin poisoning clinical cases, in order to optimize therapeutic decision-making. Our results allowed to classify drugs as a function of their influence on one major parameter: patient survival. Active principles were classified as first intention, second intention, adjuvant or controversial pharmaco-therapeutic clinical intervention. We conclude that (1) retrospective multidimensional multivariate statistic analysis of complex clinical dataset might help future therapeutic decision-making and (2) drugs such as silybin, N-acetylcystein and putatively ceftazidime are clearly associated, in amatoxin poisoning context, with higher level of patient survival.

Early molecular adsorbents recirculating system treatment of Amanita mushroom poisoning

Acute poisoning due to ingestion of hepatotoxic Amanita sp. mushrooms can result in a spectrum of symptoms, from mild gastrointestinal discomfort to life-threatening acute liver failure. With conventional treatment, Amanita phalloides mushroom poisoning carries a substantial risk of mortality and many patients require liver transplantation. The molecular adsorbent recirculating system (MARS) is an artificial liver support system that can partly compensate for the detoxifying function of the liver by removing albumin-bound and water-soluble toxins from blood. This treatment has been used in acute liver failure to enable native liver recovery and as a bridging treatment to liver transplantation. The aim of the study is to evaluate the outcome of 10 patients with Amanita mushroom poisoning who were treated with MARS. The study was a retrospectively analyzed case series. Ten adult patients with accidental Amanita poisoning of varying severity were treated in a liver disease specialized intensive care unit from 2001 to 2007. All patients received MARS treatment and standard medical therapy for mushroom poisoning. The demographic, laboratory, and clinical data from each patient were recorded upon admission. The one-year survival and need for liver transplantation were documented. The median times from mushroom ingestion to first-aid at a local hospital and to MARS treatment were 18 h (range 14-36 h) and 48 h (range 26-78 h), respectively. All 10 patients survived longer than one year. One patient underwent a successful liver transplantation. No serious adverse side-effects were observed with the MARS treatment. In conclusion, MARS treatment seems to offer a safe and effective treatment option in Amanita mushroom poisoning.

Benzylpenicillin, acetylcysteine and silibinin as antidotes in human hepatocytes intoxicated with alpha-amanitin

Fatalities due to mushroom poisonings are increasing worldwide, with high mortality rate resulting from ingestion of amanitin-producing species. Intoxications caused by amanitin-containing mushrooms represent an unresolved problem in clinical toxicology since no specific and fully efficient antidote is available. The objective of this study was a comparative evaluation of benzylpenicillin (BPCN), acetylcysteine (ACC) and silibinin (SIL) as an antidotes in human hepatocytes intoxicated with alpha-amanitin (alpha-AMA). All experiments were performed on cultured human hepatocytes. Cytotoxicity evaluation of cultured cells using MTT assay and measurement of lactate dehydrogenase (LDH) activity was performed at 12, 24 and 48h of exposure to alpha-AMA and/or antidotes. The significant decline of cell viability and significant increase of LDH activity were observed in all experimental hepatocyte cultures after 12, 24 and 36h exposure to alpha-AMA at concentration 2microM. Exposure of the cells to alpha-AMA resulted also in significant reduction of cell spreading and attachment. However, addition of tested antidotes to experimental cultures significantly stimulated cell proliferation and attachment. In cell cultures exposed simultaneously to alpha-AMA and tested antidotes cytotoxic parameters (MTT and LDH) were not significantly different from control incidences. The cytoprotective effect of all antidotes was not dose-related, which reflects a high efficacy of all these substances. Administration of studied antidotes was not associated with any adverse effects in hepatocytes. The administration of ACC, BPCN or SIL to human hepatocyte cultures showed a similar strong protective effect against cell damage in alpha-AMA toxicity.

Amanita smithiana mushroom ingestion: a case of delayed renal failure and literature review

INTRODUCTION

In the Pacific Northwest a new pattern of mushroom ingestion has emerged, attributed to Amanita smithiana, in which renal failure has been the predominant manifestation.

CASE REPORT

A 55-year-old male ate 3 raw wild mushrooms in a salad and had onset of severe nausea and vomiting within 6 hours. His vital signs were unremarkable. His labs were significant for a BUN of 14 mg/dL (5.0 mmol/L), and a creatinine of 1.0 mg/dL (88 umol/L), transaminases were elevated with an AST of 56 U/L (nl 9-40) and an ALT of 131 U/L (nl 14-72). Treatment was initiated with N-acetyl cysteine, penicillin, and milk thistle extract on the presumption that this was an amanitin-toxin containing mushroom. He developed acute renal failure that was not responsive to our treatment. Dialysis started on day 4 with a creatinine of 6.5 mg/dL, which peaked on day 7 at 10.2 mg/dL. We were able to obtain a positive mushroom identification by a mycologist as Amanita smithiana. The patient was discharged from the hospital for outpatient dialysis on day 10 and dialysis catheter was removed 39 days after ingestion with a creatinine of 1.4 mg/dL (123.8 umol/L).

DISCUSSION

Amanita smithiana mushroom poisoning presents within 6 hours of ingestion with GI toxicity, and develops delayed onset of renal insufficiency over the first 1 to 4 days. The early hospitalization of this case allowed a profile of the onset of liver and renal injury. Mild elevation of hepatic transaminases occurred on presentation and peaked 24 hours after the ingestion. Renal injury was detected 1 day after presentation, and progressed to require hemodialysis by 4 days postingestion. This pattern of delayed-onset renal toxic mushroom ingestion is emerging among mushroom ingestions in Western North America.

[Cholestasis and liver dysfunction in critical care patients]

Cornerstones of the diagnostic investigations of disturbances in liver function are analysis and sophisticated evaluation of serum liver enzymes, bilirubin and ammonia. Coagulation factors, serum albumin and cholinesterase levels are indicators of the hepatic metabolic capacity. Dynamic assessment of complex liver functions allows quantification of the hepatic metabolic activity and excretory function. Imaging techniques permit visualization of the size and texture of the liver, the vascular supply and perfusion as well as an assessment of the gall bladder and the extra-hepatic and intra-hepatic bile ducts. Manifold causes for cholestasis and/or liver dysfunction are known, such as ventilation with high pressure, total parenteral nutrition, shock, hypoxia and certain drugs. Obstructive cholestasis requires reconstitution of bile duct drainage, while non-obstructive cholestasis primarily requires treatment of the causative disease. The symptomatic therapy of liver insufficiency is rarely possible via direct treatment of the cause, but mostly requires specific management of secondary organ dysfunctions related to hepatic dysfunction including circulatory failure, hepatorenal syndrome and hepatic encephalopathy. In rare cases a temporary liver surrogate is necessary. The molecular absorbent recirculating system (MARS), a form of extracorporeal albumin dialysis, is introduced as a modality for the treatment of liver failure.

Renal and hepatic injury with elevated cardiac enzymes in Amanita phalloides poisoning: a case report

Amatoxins are one of the most potent toxins that cause hepatic and renal failure. However, this is the first report demonstrating an elevation of cardiac enzymes in a patient with Amanita phalloides poisoning. A 56-year-old male was admitted to the emergency department (ED) 42 h after an unknown type of mushroom ingestion. Hepatic, renal function tests, amylase and cardiac enzymes (troponin I, creatine kinase (CK), CK-MB isoenzyme and myoglobin) were found elevated in his blood chemistry. The electrocardiogram disclosed sinus tachycardia. Aggressive treatment with fluids, activated charcoal, penicillin G and silibinin were started. The patient was sent to hemodialysis because of anuria. During follow-up, biochemical parameters and clinical findings improved. The patient was discharged from the hospital following the arrangement of hemodialysis schedule because of the chronic renal failure. False elevations of cardiac markers may confuse the clinicians in differential diagnosis of myocardial infarction in ED. In our patient, amatoxins that have bound the actin filaments within myocardiocytes or renal cells and/or its effects as circulating anti-troponin antibodies might result in elevation of cardiac markers. Elevated cardiac enzyme levels without any acute coronary syndrome are probable in mushroom poisoning cases involving amatoxin ingestion.

Gene family encoding the major toxins of lethal Amanita mushrooms

Amatoxins, the lethal constituents of poisonous mushrooms in the genus Amanita, are bicyclic octapeptides. Two genes in A. bisporigera, AMA1 and PHA1, directly encode alpha-amanitin, an amatoxin, and the related bicyclic heptapeptide phallacidin, a phallotoxin, indicating that these compounds are synthesized on ribosomes and not by nonribosomal peptide synthetases. alpha-Amanitin and phallacidin are synthesized as proproteins of 35 and 34 amino acids, respectively, from which they are predicted to be cleaved by a prolyl oligopeptidase. AMA1 and PHA1 are present in other toxic species of Amanita section Phalloidae but are absent from nontoxic species in other sections. The genomes of A. bisporigera and A. phalloides contain multiple sequences related to AMA1 and PHA1. The predicted protein products of this family of genes are characterized by a hypervariable "toxin" region capable of encoding a wide variety of peptides of 7-10 amino acids flanked by conserved sequences. Our results suggest that these fungi have a broad capacity to synthesize cyclic peptides on ribosomes.

Mushroom poisoning

OBJECTIVE

We aimed to review characteristics of mushrooms and mushroom poisoning and compare clinical picture, laboratory data, treatment modalities and prognostic factors in children with amanita intoxication and non-amanita mushroom poisoning.

METHODS

We analyzed 39 pediatric patients through 1994-2004, retrospectively from the patient files and evaluated the patients in two groups as patients with amanita intoxication and patients with non-amanita mushroom poisoning. All of the cases were admitted to the hospital in autumn. Twenty three (59%) of the patients were female and 16 (41%) were male. Mean age of the patients was 8.05 +/- 2.10 years.

RESULTS

Amanita phalloides toxin was detected in the serum in 8 patients. Eleven (28%) of the cases were strongly suggestive of amanita poisoning but alpha amanitin level could not be studied. The average time of appearance of symptoms after mushroom consumption, duration of symptoms, hospital stay, serum AST, ALT, PT and creatinine levels were significantly higher in patients with amanita poisoning (p<0.01). Conventional therapy, antidote therapy together with hemoperfusion were carried out in 16 (41%) of the patients. Four of the patients in whose blood amatoxin was detected (50%) and 3 of the patients highly suggestive of amanita poisoning (30%), totally 7 patients died of hepatic coma. The average time of admission to hospital, mean AST, ALT, creatinine and PT values at 3rd day were significantly higher in patients who died of hepatic coma. Prognosis was better in case of early admittance to hospital in patients with amanita poisoning.

CONCLUSION

Early diagnosis and treatment in mushroom poisoning can be life saving. Public awareness is very important in prevention of intoxication as well as encouraging early admission to hospitals.

Amatoxin poisoning: a 15-year retrospective analysis and follow-up evaluation of 105 patients

INTRODUCTION

Fatalities due to mushroom poisonings are increasing worldwide, with more than 90% of deaths resulting from ingestion of amatoxin-containing species.

METHODS

A retrospective evaluation of the history and clinical outcome of each patient treated from 1988 to 2002 in the Toxicological Unit of Careggi General Hospital (University of Florence, Italy) for amatoxin poisoning. Data included the biological parameters monitored, the treatment protocols used (intensive fluid and supportive therapy, restitution of the altered coagulation factors, multiple-dose activated charcoal, mannitol, dexamethasone, glutathione, and penicillin G), and outpatient follow-up evaluations.

RESULTS

The clinical data of 111 patients were evaluated; their biological parameters were monitored every 12-24 hours until discharge. Two patients died; both were admitted to the hospital more than 60 hours after mushroom ingestion. Of all the laboratory parameters evaluated, the evolution of hepatic transaminases and prothrombin activity over four days were the most predictive indicators of recovery or death. Our follow-up evaluation of 105 patients demonstrated that our survivors recovered completely.

CONCLUSIONS

Our experience indicates that the protocol used in our Toxicologicy Unit is effective for amatoxin poisoning, and that all patients treated within 36 hours after mushroom ingestion were cured without sequelae.