Albendazole in hydatid disease--hepatocellular toxicity

Who Let the Dogs Out? Unmasking the Neglected: A Semi-Systematic Review on the Enduring Impact of Toxocariasis, a Prevalent Zoonotic Infection

Toxocariasis remains an important neglected parasitic infection representing one of the most common zoonotic infections caused by the parasite Toxocara canis or, less frequently, by Toxocara cati. The epidemiology of the disease is complex due to its transmission route by accidental ingestion of embryonated Toxocara eggs or larvae from tissues from domestic or wild paratenic hosts. Even though the World Health Organization and Centers for Disease Control classified toxocariasis amongst the top six parasitic infections of priority to public health, global epidemiological data regarding the relationship between seropositivity and toxocariasis is limited. Although the vast majority of the infected individuals remain asymptomatic or experience a mild disease, the infection is associated with important health and socioeconomic consequences, particularly in underprivileged, tropical, and subtropical areas. Toxocariasis is a disease with multiple clinical presentations, which are classified into five distinct forms: the classical visceral larva migrans, ocular toxocariasis, common toxocariasis, covert toxocariasis, and cerebral toxocariasis or neurotoxocariasis. Anthelmintic agents, for example, albendazole or mebendazole, are the recommended treatment, whereas a combination with topical or systemic corticosteroids for specific forms is suggested. Prevention strategies include educational programs, behavioral and hygienic changes, enhancement of the role of veterinarians, and anthelmintic regimens to control active infections.

Albendazole and Mebendazole as Anti-Parasitic and Anti-Cancer Agents: an Update

The use of albendazole and mebendazole, i.e., benzimidazole broad-spectrum anthelmintics, in treatment of parasitic infections, as well as cancers, is briefly reviewed. These drugs are known to block the microtubule systems of parasites and mammalian cells leading to inhibition of glucose uptake and transport and finally cell death. Eventually they exhibit ovicidal, larvicidal, and vermicidal effects on parasites, and tumoricidal effects on hosts. Albendazole and mebendazole are most frequently prescribed for treatment of intestinal nematode infections (ascariasis, hookworm infections, trichuriasis, strongyloidiasis, and enterobiasis) and can also be used for intestinal tapeworm infections (taeniases and hymenolepiasis). However, these drugs also exhibit considerable therapeutic effects against tissue nematode/cestode infections (visceral, ocular, neural, and cutaneous larva migrans, anisakiasis, trichinosis, hepatic and intestinal capillariasis, angiostrongyliasis, gnathostomiasis, gongylonemiasis, thelaziasis, dracunculiasis, cerebral and subcutaneous cysticercosis, and echinococcosis). Albendazole is also used for treatment of filarial infections (lymphatic filariasis, onchocerciasis, loiasis, mansonellosis, and dirofilariasis) alone or in combination with other drugs, such as ivermectin or diethylcarbamazine. Albendazole was tried even for treatment of trematode (fascioliasis, clonorchiasis, opisthorchiasis, and intestinal fluke infections) and protozoan infections (giardiasis, vaginal trichomoniasis, cryptosporidiosis, and microsporidiosis). These drugs are generally safe with few side effects; however, when they are used for prolonged time (>14-28 days) or even only 1 time, liver toxicity and other side reactions may occur. In hookworms, Trichuris trichiura, possibly Ascaris lumbricoides, Wuchereria bancrofti, and Giardia sp., there are emerging issues of drug resistance. It is of particular note that albendazole and mebendazole have been repositioned as promising anti-cancer drugs. These drugs have been shown to be active in vitro and in vivo (animals) against liver, lung, ovary, prostate, colorectal, breast, head and neck cancers, and melanoma. Two clinical reports for albendazole and 2 case reports for mebendazole have revealed promising effects of these drugs in human patients having variable types of cancers. However, because of the toxicity of albendazole, for example, neutropenia due to myelosuppression, if high doses are used for a prolonged time, mebendazole is currently more popularly used than albendazole in anti-cancer clinical trials.

The Antitumor Potentials of Benzimidazole Anthelmintics as Repurposing Drugs

The development of refractory tumor cells limits therapeutic efficacy in cancer by activating mechanisms that promote cellular proliferation, migration, invasion, metastasis, and survival. Benzimidazole anthelmintics have broad-spectrum action to remove parasites both in human and veterinary medicine. In addition to being antiparasitic agents, benzimidazole anthelmintics are known to exert anticancer activities, such as the disruption of microtubule polymerization, the induction of apoptosis, cell cycle (G2/M) arrest, anti-angiogenesis, and blockage of glucose transport. These antitumorigenic effects even extend to cancer cells resistant to approved therapies and when in combination with conventional therapeutics, enhance anticancer efficacy and hold promise as adjuvants. Above all, these anthelmintics may offer a broad, safe spectrum to treat cancer, as demonstrated by their long history of use as antiparasitic agents. The present review summarizes central literature regarding the anticancer effects of benzimidazole anthelmintics, including albendazole, parbendazole, fenbendazole, mebendazole, oxibendazole, oxfendazole, ricobendazole, and flubendazole in cancer cell lines, animal tumor models, and clinical trials. This review provides valuable information on how to improve the quality of life in patients with cancers by increasing the treatment options and decreasing side effects from conventional therapy.

Recurrent albendazole-induced acute hepatitis

El albendazol es un medicamento usado para tratar infecciones por helmintos y usualmente presenta pocos o ningún efecto secundario. A pesar de que hay un incremento transitorio de enzimas hepáticas luego de su uso, existe poca evidencia en la literatura en la que se reporte lesión hepática luego de automedicación con albendazol. En este informe, el paciente se presentó con hepatitis aguda luego de automedicarse con albendazol. El paciente cuenta además con una historia de episodios similares después de haber usado el fármaco. Se evaluada la causalidad con el método de evaluación de causalidad de Roussel Uclaf del Concejo para Organizaciones Internacionales de Ciencias Médicas, cuyo resultado fue un puntaje de 10, lo que indicó una alta probabilidad de lesión hepática inducida por albendazol al cabo de realizarse una investigación rigurosa y de excluir otras posibles causas de la condición física del paciente. En conclusión, aunque es ideal agilizar el proceso para combatir a los helmintos, es necesario intensificar la necesidad de monitorizaciones de calidad para evitar reacciones adversas como la hepatitis inducida por medicamentos. Asimismo, la automedicación de cualquier medicamento debe ser siempre evitada.

Drug-Induced Liver Failure Requiring Liver Transplant: Report and Review of the Role of Albendazole in Managing Echinococcal Infection

Albendazole is often used as adjunctive therapy in the treatment of echinococcal infection to reduce cyst viability before and prevent recurrence after surgical treatment. In this report, we present a 38-year-old Iraqi woman with Echinococcus initiated on albendazole therapy who developed acute liver failure 6 weeks after treatment. Investigation for common viral and autoimmune causes of liver injury was unremarkable, and a liver biopsy revealed changes consistent with severe, drug-induced liver injury. Despite discontinuation of albendazole, liver function continued to deteriorate, prompting rescue with an orthotopic liver transplant. Often used perioperatively in the management of Echinococcus infection, albendazole can induce idiosyncratic severe liver injury, mandating close monitoring for hepatotoxicity.

Medical treatment versus "Watch and Wait" in the clinical management of CE3b echinococcal cysts of the liver

Background

Available treatments for uncomplicated hepatic cystic echinococcosis (CE) include surgery, medical therapy with albendazole (ABZ), percutaneous interventions and the watch-and-wait (WW) approach. Current guidelines indicate that patients with hepatic CE should be assigned to each option based on cyst stage and size, and patient characteristics. However, treatment indications for transitional CE3b cysts are still uncertain. These cysts are the least responsive to non-surgical treatment and often present as indolent, asymptomatic lesions that may not warrant surgery unless complicated. Evidence supporting indications for treatment of this stage is lacking. In the attempt to fill this gap before the implementation of randomized clinical trials, we compared the clinical behavior of single hepatic CE3b cysts in 60 patients followed at the WHO Collaborating Centre for Cystic Echinococcosis of the University of Pavia.

Methods

We analyzed retrospectively data of 60 patients with hepatic CE3b cysts seen at our clinic over 27 years, who either received ABZ or were monitored with WW. Univariate and multivariate analysis were performed to investigate the effect on outcome (inactivation or relapse) of variables such as age, sex, origin, treatment, cyst size and presence of other echinococcal hepatic cysts using a multiple failure Cox proportional hazard model.

Results

ABZ treatment was positively associated with inactivation (p < 0.001), but this was not permanent, and no association was found between therapeutic approach and relapse (p = 0.091). No difference was found in the rate of complications between groups.

Conclusions

In conclusion, our study shows that ABZ treatment induces temporary inactivation of CE3b cysts, while during WW cysts remain stable over time. As the rate of adverse events during periods of ABZ treatment and WW did not differ significantly in the follow-up period considered in this study (median 43 months, IQR 10.7-141.5), expectant management might represent a valuable option for asymptomatic CE3b cysts when strict indication for surgery is absent and patients comply with regular long-term follow-up.

Electronic supplementary material

The online version of this article (doi:10.1186/1471-2334-14-492) contains supplementary material, which is available to authorized users.

Albendazole-induced associated acute hepatitis and bicytopenia

Acute hepatitis induced by albendazole is rarely reported. We describe herein an original case of acute hepatitis associated with bicytopenia after albendazole intake. This paper is the first to describe a possible association of a hematologic disorder and acute hepatitis, both induced by albendazole therapy.

Acute drug-induced hepatitis caused by albendazole

Albendazole binds to parasite's tubulin inhibiting its glucose absorption. Its common adverse effects are nausea, vomiting, constipation, thirst, dizziness, headache, hair loss and pruritus. Although mainly metabolized in the liver, abnormal liver function tests were a rare adverse effect during clinical trials and we found no literature about albendazole-induced hepatitis requiring admission. This patient had a previous history of albendazole ingestion in 2002 resulting in increase of liver function tests. And in 2005, the episode repeated. We evaluated the patient for viral hepatitis, alcoholic liver disease, and autoimmune hepatitis, but no other cause of hepatic injury could be found. Liver biopsy showed periportal steatosis and periportal necrosis. The initial abnormal liver function test improved only with supportive care. These findings and the Roussel Uclaf Causality Assessment Method of the Council for International Organizations of Medical Sciences (RUCAM/CIOMS) score of 9 are compatible with drug-induced hepatitis so we report the case of this patient with a review of the literature.

First case of ivermectin-induced severe hepatitis

Loiasis, caused by the filarial parasite Loa loa, is endemic in West and Central Africa. Ivermectin has been shown to be an effective treatment of loiasis. We report the case of a 20-year-old woman originally from Cameroon who was infected by the L. loa parasite and developed severe hepatitis, identified 1 month after a single dose of ivermectin. Liver biopsy showed intralobular inflammatory infiltrates, confluent necrosis and apoptosis, compatible with drug-induced liver disease. To our knowledge, this is the first case of ivermectin-induced severe liver disease published in the literature.

Anthelminthic drug safety and drug administration in the control of soil-transmitted helminthiasis in community campaigns

Helminth infections are now recognised as being a major health priority worldwide. Morbidity due to these infections can be controlled at a reasonable cost by means of periodic chemotherapy using effective drugs. Deworming campaigns targeted at high risk groups, such as school-age children, pre-school children and women of child-bearing age, are the mainstay of the control strategy launched by WHO. Anthelminthic drugs can be delivered effectively through the school system, women's associations or other community-based interventions, each of which often lack health personnel supervision. The safety of anthelminthic drugs is, therefore, of paramount importance and side effects have to be recognised and monitored, especially when generic drugs are widespread. Four anthelminthic drugs are considered to provide appropriate single dose treatment against soil-transmitted helminthiasis: albendazole, levamisole, mebendazole and pyrantel. Side effects, at the dosage recommended for deworming, have been described as negligible and self-limiting. However, a limited number of reports have associated more severe adverse reactions to the distribution of anthelminthic medicines. Even if the available information cannot confirm a cause-effect relationship, it is essential that these effects are known. Ministries of Health can then set up efficient and safe delivery, monitoring and referral systems, in order to minimise the risk and maximise the benefit of periodic anthelminthic chemotherapy in communities where soil-transmitted helminthiasis is endemic.

Albendazole for the treatment of echinococcosis

Twenty years after the first cases of echinococcal disease were treated with albendazole, it has become an important component in the overall management of both cystic and alveolar echinococcosis. This paper reviews some of the key steps and issues facing those who work in clinical research and who deal on a day-to-day basis with echinococcal disease. In many situations, chemotherapy alone is sufficient, but it is also used as an adjunct to surgery and to minimally invasive approaches to cyst management. While treatment may not be as effective as hoped, attempts to provide new regimens are progressing to increase cure rates further. There is now a greater understanding of the limitations of all approaches, and treatment guidelines as developed by the World Health Organization are now widely followed. As diagnostic tools are ever more widely available, the question as to who should be treated in endemic communities has to be answered.

Control strategies for human intestinal nematode infections

In recent years significant progress has been made in understanding the ecology, epidemiology and related morbidity and development of new tools for the control of soil-transmitted helminths. Such knowledge has recognized the impact of helminth infections on the health of infected groups and has created a rational basis for their control. Schoolchildren harbour some of the most intense helminthic infections, which produce adverse effects on health, growth and scholastic performance. However, although great effort has been put into targeting school-age children, women of child-bearing age and pre-school children are two other groups at high risk of morbidity due to intestinal nematode infections. Highly effective and safety-tested, single-dose anthelminthic drugs are now available, permitting periodical deworming of schoolchildren and other high-risk groups at affordable prices. Four anthelminthics against all intestinal nematodes are included in the WHO Essential Drug List (albendazole, levamisole, mebendazole and pyrantel). Recently ivermectin has also been registered for use against Strongyloides stercoralis in humans. Several well-monitored country experiences have shown that chemotherapy-based control of morbidity due to soil-transmitted helminths is possible and highly cost-effective.

Albendazole in treatment of human cystic echinococcosis: 12 years of experience

This review paper examines the evidence from published and previously unpublished sources for the efficacy and safety of albendazole (ABZ) obtained in the last 12 years. Benzimidazole treatment alone is not ideal, requiring prolonged administration over many weeks, with an unpredictable outcome in terms of response rates in individuals. However, studies have shown that treatment with albendazole in E. granulosus infection can result in an apparent cure in up to 30% of cases, with a further 40-50% showing objective evidence of response when followed in the short term. Some studies have demonstrated that even patients who do not show obvious initial evidence of response may be found to be cured when followed up over several years. Duration of therapy and dose are also important, and with ABZ, efficacy seems to increase with exposure up to 3 months in the commoner cyst sites. Formal dose ranging and minimal effective dose studies have not been performed, but the current dose of 800 mg daily appears to be adequate. The issue of cyclical versus continuous treatment still has to be resolved. Data on ABZ safety has been accumulated over the past 12 years of marketing. The profile shows that liver function abnormalities are common although rarely treatment limiting, while occasional hematological changes affecting the white cells may be more serious. The safety data supplies the rationale for monitoring of patients during treatment. On balance ABZ has been shown to be a useful advance in the management of cystic echinococcosis both when used as sole treatment or as an adjunct to surgery or other treatments.

Renal echinococcosis: clinical study of 34 cases

PURPOSE

Hydatid disease, a cyclo-zoonotic parasitic infestation caused by the larval stage of the cestode Echinococcus granulosus, is prevalent worldwide. We reviewed the clinical findings of a large series of renal hydatidosis treated in an endemic area with special emphasis on diagnostic pitfalls.

MATERIALS AND METHODS

A retrospective 15-year review in a rural area of central Spain (600,000 population), with a global incidence of hydatidosis of 10 new cases per 100,000 population per year, revealed 34 with renal echinococcosis treated surgically (3 to 4% of officially confirmed cases of hydatidosis). Clinical, radiological and laboratory data were analyzed.

RESULTS

Renal hydatid disease mimicked other diseases. The combination of clinical history, imaging studies, and serological and urine investigation yielded a reliable pretreatment diagnosis in only 50% of cases and a presumptive diagnosis in 71%. Among imaging studies computerized tomography was the most valuable diagnostic examination. Moderate eosinophilia was found in half of the cases, while a third had scoleces in the urine. A diagnostic and therapeutic algorithm is presented.

CONCLUSIONS

Preoperative diagnosis of renal hydatid disease is difficult even in an endemic zone. Imaging studies are suggestive but usually inconclusive, and the differential diagnosis with a renal tumor or complicated cyst may not be made without surgery. Renal sparing surgery is possible in a significant proportion of cases, particularly when preoperative diagnosis has been considered. Significant surgical morbidity can be expected, and the risk of anaphylaxis and hydatid seeding, although low, should not be overlooked.

Treatment of experimental alveolar echinococcosis with albendazole: a 1H NMR spectroscopic study

The Meriones unguiculatus (jird) – Echinococcus multilocularis host–parasite model was used to evaluate metabolic changes in livers and cysts treated with albendazole (ABZ). Hydrogen-1 nuclear magnetic resonance spectra of liver extracts showed that livers of uninfected jirds fed olive oil contained more glycine but less glycerophosphocholine (GPC) than those of uninfected untreated controls. When ABZ was added to the olive oil and tested on uninfected animals, other modifications in the metabolic profile of the liver could be seen. While the concentration of GPC stayed reduced and that of glycine reverted to normal, the levels of glycogen, phosphocreatine/creatine (PCr/Cr), succinate, and acetate were lower than those in the normal liver. The metabolic pathology in this organ was further magnified in jirds infected with E. multilocularis. In this case, the liver was depleted of glycogen, glucose, taurine, GPC, and acetate, but had more betaine, phosphocholine, choline, PCr/Cr, and succinate. These abnormalities were markedly diminished by ABZ treatment, with only glycogen, GPC, and acetate concentrations being low when the treatment was terminated. Also, the drug suppressed the growth of the parasite by 75%, and extracts of these parasite cysts contained less glycogen, glycine, succinate, acetate, and alanine but more taurine, GPC, and PCr/Cr than extracts of those from untreated hosts.

Albendazole therapy of hydatid disease: 2-year follow-up of 40 cases

Forty patients with 63 Echinococcus granulosus cysts affecting different sites were treated with albendazole and have been followed up for at least 24 months from completion of therapy. Twenty-one patients (53%) with 37 cysts (59%) showed evidence of healing. The criteria and pattern of healing are outlined. The most serious complication of albendazole therapy was hepatoxic jaundice, which occurred in 5% of patients. Recurrence during the observation period was encountered in 9.5% of patients with a positive response. It is suggested that patients suffering from uncomplicated hydatid disease should be given the benefit of a trial course of albendazole therapy, before surgery is undertaken.

Albendazole in hydatid disease: Results in 22 patients

A prospective study to evaluate the effect of albendazole in the treatment of echinococcus granulosus was conducted at the Gastroenterology Unit, Armed Forces Hospital, Riyadh since April 1985 to present involving 22 patients mainly with liver hydatid disease. Of these patients, 30% had a previous history of surgery for recurrence of previously operated hydatid cysts. The duration treatment and follow up period ranged from two months to three years. The only side effect was hair loss in two patients which was fully reversible on the termination of treatment. The following results were achieved: Radiological disappearance of the liver cysts were achieved in eight patients. Four of eight patients were treated only with albendazole and the other four patients with rupture liver cysts to the biliary tree were treated with a combination of non-surgical endoscopic method, hypertonic saline irrigation and albendazole. In the remaining 14 patients, 5 (22.72%) had a 30% to 60% reduction in cyst size. Intracystic change was noted in five patients (22.72%), in two patients the cyst ruptured and there was no change in the cyst size in two patients (9.9%). This study demonstrate that albendazole is a promising drug for the treatment of hydatid disease.

Membrane transport of amino acid enantiomers in protoscoleces of Echinococcus granulosus (Cestoda)

Protoscoleces of Echinococcus granulosus absorb both L- and D-alanine. Concentration ratios exceed 1 with values for D-alanine exceeding those for the L-isomer, suggesting that both are absorbed by active mechanisms. Uptake of both isomers involves both diffusion and carrier-mediated components. Values for the diffusion component (Kd) for L- and D-alanine were 0.21 and 0.38 nmol mg-1 protein/1.5 min mM-1 respectively, and values for Kt, the transport constants, 0.17 mM and 0.21 mM respectively. Uptake of both isomers was inhibited competitively by a number of other amino acids.

Comparison of Albendazole and Praziquantel therapy of Echinococcus granulosus in naturally infected sheep

The effects of albendazole (10 mg kg-1 day-1) and praziquantel (50 mg kg-1 day-1) for 6 weeks on naturally infected sheep with pulmonary cysts of Echinococcus granulosus of proven viability were studied. Immediately following therapy, one of three sheep treated with praziquantel had viable cysts and 7 months later one of two sheep had viable cysts. One sheep died during albendazole therapy, but 7 months following therapy only one of five sheep had viable cysts. Electron microscopy demonstrated necrotic germinal layer tissue in most albendazole-treated cysts and praziquantel also had an effect on cyst ultrastructure. These data suggest that recurrence in humans treated with albendazole may be small. Whilst praziquantel was not particularly effective in this animal model, its clear effect on the ultrastructure suggests that an increased dose and combination therapy with albendazole may be more effective.

Chemotherapy of Echinococcus infection in man with albendazole

Since 1983 data have been collected on the outcome of treatment of apparently active Echinococcus granulosus hydatid cysts with albendazole. Most patients received 800 mg albendazole daily in cycles of 28 d with 14 d between cycles, with a mean duration of 2.5 cycles (range 1-12). From an initial set of over 500 cases, 253 patients were evaluated for efficacy, with 269 hepatic, 86 pulmonary, 50 peritoneal and 51 cysts at other sites being individually assessed. 72 patients (28.5%) were regarded as cured, 129 (51%) as improved, 46 (18.1%) as unchanged and 6 (2.4%) were worse. 47 patients underwent surgery after treatment and viability was demonstrated in only 5 cysts (10.6%). Recurrence was observed in 4 of 29 non-surgical cases (13.8%) from whom a follow-up of at least 24 months was available. 35 cases of E. multilocularis infection were assessed, with cure in 2, improvements in 4, stabilization in 25 and progression in 4 cases. Side effects of treatment were uncommon. Liver function abnormalities occurred in about 20% (4% withdrawn) and there was a tendency for leucopenia to occur in E. multilocularis patients. Albendazole appears to be effective both for chemotherapy in inoperable cases of hydatid disease and for prophylaxis before surgery.

Combination chemotherapy of Echinococcus granulosus--in vitro studies

Both benzimidazole carbamates and isoquinoline compounds have activity against protoscoleces of Echinococcus granulosus in culture in vitro; combinations of albendazole sulphoxide and praziquantel are more effective than either agent alone.

Pre-operative albendazole therapy for hydatid cyst

Surgical management of hydatid cyst is associated with recurrence in 10 per cent of patients. The role of perioperative chemotherapy in prevention of recurrence has not been extensively explored. Sixteen patients with Echinoccus granulosus were treated with albendazole 10 mg kg-1 before operation; of fourteen patients who received albendazole for 1 month or more before operation only one (with doubtful therapeutic compliance) had viable protoscoleces, in contrast both of the two remaining patients who received only 1 and 3 weeks therapy had live disease at the time of operation. A 1 month pre-operative course of albendazole kills most if not all protoscoleces within hydatid cysts in man. This may allow pre-operative 'sterilization' of cysts and a reduction in the risk of recurrence.