Anthelmintics for people with neurocysticercosis.

BACKGROUND: Neurocysticercosis is a parasitic infection of the central nervous system by the larval stage of the pork tapeworm and is a common cause of seizures and epilepsy in endemic areas. Anthelmintics (albendazole or praziquantel) may be given alongside supportive treatment (antiepileptics/analgesia) with the aim of killing these larvae (cysticerci), with or without corticosteroid treatment. However, there are potential adverse effects of these drugs, and the cysticerci may eventually die without directed anthelminthic treatment. OBJECTIVES: To assess the effects of anthelmintics on people with neurocysticercosis. SEARCH METHODS: We searched the Cochrane Infectious Diseases Group Specialized Register, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, LILACS, the WHO ICTRP, and ClinicalTrials.gov, up to 21 October 2020. SELECTION CRITERIA: Randomized controlled trials comparing anthelmintics and supportive treatment (+/- corticosteroids) with supportive treatment alone (+/- corticosteroids) for people with neurocysticercosis. DATA COLLECTION AND ANALYSIS: Two review authors independently screened the title and abstract of all articles identified by the search. We obtained full-text articles to confirm the eligibility of all studies that passed screening. One review author extracted data, which a second review author checked. Two review authors assessed the risk of bias of each trial and performed GRADE assessments. In cases of disagreement at consensus discussion stage between review authors, we consulted a third review author. We calculated risk ratios (RR) for dichotomous variables, with 95% confidence intervals (CIs) for pooled data from studies with similar interventions and outcomes. MAIN RESULTS: We included 16 studies in the review. Only two studies investigated praziquantel and did not report data in a format that could contribute to meta-analysis. Most results in this review are therefore applicable to albendazole versus placebo or no anthelmintic. The aggregate analysis across all participants with neurocysticercosis did not demonstrate a difference between groups in seizure recurrence, but heterogeneity was marked (RR 0.94, 95% CI 0.78 to 1.14; 10 trials, 1054 participants; I2 = 67%; low-certainty evidence). When stratified by participants with a single cyst or multiple cysts, pooled analysis suggests that albendazole probably improves seizure recurrence for participants with a single cyst (RR 0.61, 95% CI 0.4 to 0.91; 5 trials, 396 participants; moderate-certainty evidence). All studies contributing to this analysis recruited participants with non-viable, intraparenchymal cysts only, and most participants were children. We are uncertain whether or not albendazole reduces seizure recurrence in participants with multiple cysts, as the certainty of the evidence is very low, although the direction of effect is towards albendazole causing harm (RR 2.05, 95% CI 1.28 to 3.31; 2 trials, 321 participants; very low-certainty evidence). This analysis included a large study containing a highly heterogeneous population that received an assessment of unclear risk for multiple 'Risk of bias' domains. Regarding radiological outcomes, albendazole probably slightly improves the complete radiological clearance of lesions (RR 1.22, 95% CI 1.07 to 1.39; 13 trials, 1324 participants; moderate-certainty evidence) and the evolution of cysts (RR 1.27, 95% CI 1.10 to 1.47; 6 trials, 434 participants; moderate-certainty evidence). More adverse events appeared to be observed in participants treated with either albendazole or praziquantel compared to those receiving placebo or no anthelmintic. The most commonly reported side effects were headache, abdominal pain, and nausea/vomiting. AUTHORS' CONCLUSIONS: For participants with a single cyst, there was less seizure recurrence in the albendazole group compared to the placebo/no anthelmintic group. The studies contributing to this evidence only recruited participants with a non-viable intraparenchymal cyst. We are uncertain whether albendazole reduces seizure recurrence for participants with multiple cysts. We also found that albendazole probably increases radiological clearance and evolution of lesions. There were very few studies reporting praziquantel outcomes, and these findings apply to albendazole only.

Observed or Predicted Albendazole Hepatotoxicity as an Indication for a Resection Procedure in Hepatic Hydatid Disease - A Short Series of Cases.

OBJECTIVE: To highlight the role of albendazole hepatotoxicity in the choice between drainage versus a resection procedure in hepatic hydatidosis. Methods: The charts of four patients were reviewed retrospectively. In three patients, albendazole caused more than 10-fold increases in transaminase levels and was stopped. One patient had concomitant autoimmune hepatitis. Results: In the first case, two large hydatid cysts involving the right and the left hepatic veins were detected. First, left lateral sectionectomy and ligation of the right posterior portal vein branches were performed. Hypertrophy of the remnant liver allowed a safe right posterior sectionectomy two months later. In the second patient, a 9-cm cyst in segments 6 and 7 was treated with pericystectomy. The third patient had a 6-cm centrally located cyst. Pericystectomy, removal of small vesicles from the anterior section bile duct, common bile duct exploration with a T-tube placement were performed. In the patient with auto-immune hepatitis, pericystectomy was chosen for two objectives: 1) to eliminate a cavity prone to recurrence in an immunosuppressed patient 2) to avoid albendazole that may complicate the interpretation of liver function tests. The postoperative period and early follow up of all patients was uneventful. The second and the fourth patients have been followed for 56 and 17 months respectively and no recurrence has been detected. Conclusions: A resection procedure eliminates the cavity and the need for adjuvant albendazole treatment. This is a vital advantage for the small subset of patients with severe albendazole hepatotoxicity.

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.

Comparative Evaluation of Liposomal Albendazole and Tablet-Albendazole Against Hepatic Cystic Echinococcosis: A Non-Randomized Clinical Trial.

In this study, we aimed to compare the clinical efficacy of liposomal albendazole (L-ABZ) and tablet-albendazole (T-ABZ) for the treatment of human hepatic cystic echinococcosis (CE). Sixty patients with single cyst (CE1) or daughter cyst (CE2) were included in this study and were nonrandomly divided into the L-ABZ group (n = 30, 10  mg/kg per day, p.o., b.i.d.) and T-ABZ group (n = 30, 12-20 mg/kg per day, p.o., b.i.d.), respectively. The treatment duration lasted for 6 months, during which dynamic follow-up was carried out to evaluate the clinical efficacy through calculating the total effective rates (TERs). Measurement data and numerous data were analyzed by the chi-square test. Two-sided tests were performed for all the statistical tests. In our study, 2 patients were lost in the follow-up in the L-ABZ group. One patient was lost in the follow-up in the T-ABZ group, and 1 patient was withdrawal from the study due to receiving surgery. Significant difference was identified in the 3-month TERs of L-ABZ group and T-ABZ group (33.3% vs 76.7%, P < 0.05). Also, remarkable difference was noted in the 6-month TERs in the L-ABZ group and T-ABZ group (66.7% vs 93.3%, P = 0.01). No statistical difference was noticed in the incidence rate of adverse reactions in both groups (P > 0.05). Based on our study, both T-ABZ and L-ABZ are effective for treating human CE. The TER in the L-ABZ group is superior to that of T-ABZ.

Necessity of lung resection in neglected cases of pulmonary hydatidosis.

In pulmonary hydatid disease, lung resection is not a desirable treatment. Two young boys, aged 9 and 15, presented at our institution, the 9-year-old with a destroyed lung as the result of a delayed diagnosis of a giant cyst; the second with a massive hemoptysis as the result of preoperative albendazole use. Both children underwent a lobectomy for the treatment of pulmonary hydatidosis. Delayed diagnosis and use of albendazole, respectively, were considered the causes necessitating lung resection in these cases of giant and complicated pulmonary hydatid disease.

Three day albendazole therapy in patients with a solitary cysticercus granuloma: a randomized double blind placebo controlled study.

A solitary cysticercus granuloma is a benign form of neurocysticercosis. Several reports have suggested albendazole is effective in early resolution of these lesions. A short duration (7 days) albendazole therapy has been found to be effective in treatment. In this study, we evaluated a "three day course" of albendazole in a prospective randomized double- blind trial. Sixty-seven consecutive patients who presented with new-onset seizures and a solitary cysticercus granuloma were randomly allocated to receive either albendazole (15 mg/kg/day for 3 days) or placebo. All patients were treated with antiepileptic drugs. Patients were followed up for 6 months. A repeat CT of the brain was obtained at the end of 6 months of follow-up. The end points were complete resolution of the lesion on CT scan and total seizure control at 6 months follow-up. In the albendazole group complete resolution of lesions was noted in 28 of 33 patients (84.8%), while in the control group only 14 of 34 patients (41.2%) had complete resolution of the lesion (p = 0.001). Partial resolution of lesion was seen in 2 patients (6%) in the albendazole group and 4 patients (11.8%) in the control group (p = 0.06). The lesion remained unchanged in 9 cases (26.5%) in the control group only. The lesion became calcified in 7 (20.6%) and 3 (9.1%) patients in the control and albendazole groups, respectively (p = 0.187). Seizure recurrence occurred in 3 patients (9.1%) in the albendazole and 1 patient (2.9%) in the control group (p = 0.239). The three days course of albendazole was effective in resolving lesions, but there was no significant difference in seizure recurrence rates between the two treatment groups.

Monocular blindness during therapy for cerebral neurocysticercosis.

Neurocysticercosis is endemic in India, cerebral and ocular manifestations being common. A 32 yr old man on treatment with Albendazole for cerebral neurocysticercosis for 10 days presented with 3 days of painful uniocular blindness. He had only light perception in the left eye, left pupil was non-reactive to light and left disc was edematous. B-scan of eye revealed retinal detachment due to sub retinal cyst and CT brain showed multiple parenchymal cysticerci. The natural history of ocular neurocysticercosis or enhanced sub-retinal inflammation due to Albendazole therapy could have resulted in the retinal detachment in this case.

[Adverse effects of longterm, continual administration of high doses of albendazole in the treatment of echinococcal disease].

BACKGROUND/AIM: Modern treatment of cystic echinococcosis, except for surgical treatment and percutaneous drainage of cyst considers also administration of albendazole as a type of individual therapy. However, clinicians fear of the serious adverse effects of high doses of albendazole, first of all the elevation of serum transaminases activity, very frequently results in subdosing of albendazole and wrong conclusions its efficacy and safety. The aim of this study was to investigate adverse effects of a longterm, continual administration of high doses of albendazole in the treatment of patients with echinococcal disease. METHODS: A total of 42 patients (mean age 40.4 +/- 18.3 years) with echinococcal disease were included in the study. They were treated with continual administration of high doses of albendazole within the period of 4 to 6 months. The subgroups of 27 and 15 patients were treated with 15-20 mg/kg/day and with 21-25 mg/kg/day albendazole, respectively. The patients in the control group (18 with surgical treatment, 6 with percutaneous drainage of cyst) were treated with 800 mg albendazole per day (< 15 mg/kg body weight) in the cycles of 28 days (1-3 cycles) and a two-week pause between them. RESULTS: In the study group adverse effects of albendazole were registered in 20 (47.6%), whereas in the control group in 6 (30.0%) of the patients. In both subgroups elevated activity of serum transaminases were found more frequently in the study group compared to the control one (35.7% vs 25%, p < 0.05), especially in the patients who were treated with higher doses of albendazole. The patients in the study group, compared to the patients in the control group had significantly higher mean activity of serum alanin aminotransferase in the course of the second and third month of the therapy (p < 0.05). Administration of albendazole due to adverse effects was stopped in 3 (7.1%) of the patients in the study group. Two (4.8%) of them had a very high activity of serum transaminases and one had a muscle pains and high activity of serum creatine kinase. After the interruption of the therapy we documented a nonnalization of serum enzyme levels in all the patients. CONCLUSION: Longterm, continual administration of high doses of albendazole in the patients with echinococcal disease results in significant elevation of serum transaminases activity, compared to the patients treated with albendazole in the cycles, but in the majority of the patients serum transaminases activity was normalizated by the end of a 6-month period.

Calcified neurocysticercosis lesions trigger symptomatic inflammation during antiparasitic therapy.

We report a patient with neurocysticercosis who developed numerous cerebral edematous lesions while undergoing cysticidal therapy. These lesions outnumbered viable cystic lesions seen before therapy. Most new lesions were subsequently found to be associated with former calcifications not seen on initial MR imaging. Calcified neurocysticercosis lesions can trigger inflammatory reactions during therapy, and the number and location of calcified neurocysticercosis lesions may influence treatment decisions.

Albendazole trial at 15 or 30 mg/kg/day for subarachnoid and intraventricular cysticercosis.

Thirty-six patients with subarachnoid and intraventricular cysticercosis were randomly assigned to receive albendazole at 15 or 30 mg/kg/day plus dexamethasone for 8 days. Results favored a higher dose, with larger cyst reduction on MRI at 90 and 180 days and higher albendazole sulfoxide levels in plasma. An albendazole course at 30 mg/kg/day combined with corticosteroids is safe and more effective than the usual dose. A single treatment was insufficient in intraventricular and giant cysts.

The safety, tolerability and pharmacokinetics of levamisole alone, levamisole plus ivermectin, and levamisole plus albendazole, and their efficacy against Onchocerca volvulus.

Two randomized, double-blind, placebo-controlled trials, in which levamisole (2.5 mg/kg) was given alone or co-administered with ivermectin (200 microg/kg) or albendazole (400 mg), were conducted. In Trial 1, safety and drug-drug interaction were explored in 42 healthy male volunteers. During Trial 2, the safety of the same treatment regimens and their efficacy against the adult worms and microfilariae of Onchocerca volvulus were investigated in 66 infected subjects of both sexes. Safety was determined from the results of detailed clinical and laboratory examinations before treatment, during hospitalization and on day 30. The pharmacokinetic parameters for levamisole alone and the combinations were determined in Trial 1 and then compared with historical data for ivermectin and albendazole, given as single agents, to determine if drug-drug interaction had occurred. The level of efficacy against the adult worms was determined by the examination of histology sections of nodules excised 6 months posttreatment and from the changes seen in the levels of microfilaridermia within a year of treatment. Microfilaricidal efficacy was estimated from the reductions in the levels of microfilaridermia between day 0 (1 day pre-treatment) and day 30. Although the regimens were generally well tolerated, there were unexpected adverse effects in both healthy volunteers and infected subjects. Clinically significant drug-drug interactions resulted in an increase in the bio-availability of ivermectin but a reduction in that of albendazole when these drugs were co-administered with levamisole. Levamisole given alone or with albendazole had little effect on O. volvulus. The combination of levamisole with ivermectin was neither macrofilaricidal nor more effective against the microfilariae and the adult worms than ivermectin alone. The pathogenesis of the adverse events and the drug-drug interactions are discussed.

A trial of antiparasitic treatment to reduce the rate of seizures due to cerebral cysticercosis.

BACKGROUND: Neurocysticercosis is the main cause of adult-onset seizures in the developing world. Whether therapy with antiparasitic agents results in improved seizure control has been questioned because of the lack of adequate, controlled studies. METHODS: We conducted a double-blind, placebo-controlled trial in which 120 patients who had living cysticerci in the brain and seizures treated with antiepileptic drugs were randomly assigned to receive either 800 mg of albendazole per day and 6 mg of dexamethasone per day for 10 days (60 patients) or two placebos (60 patients). The patients were followed for 30 months or until they had been seizure-free for 6 months after the doses of the antiepileptic drugs had been tapered. The efficacy of treatment was measured as the decrease in the number of seizures after treatment. RESULTS: In the albendazole group, there was a 46 percent reduction in the number of seizures (95 percent confidence interval, -74 to 83 percent) during months 2 to 30 after treatment. This reduction, which was not statistically significant, was composed of a nonsignificant reduction of 41 percent in the number of partial seizures (95 percent confidence interval, -124 to 84 percent) and a significant 67 percent reduction in the number of seizures with generalization (95 percent confidence interval, 20 to 86 percent). Most of the difference in the number of partial seizures was attributable to a few patients who had many seizures during follow-up. The proportions of patients who had partial seizures during follow-up were similar in the two groups (19 of 57 in the albendazole group and 16 of 59 in the placebo group), but the patients in the placebo group had a greater tendency to have seizures with generalization (22 of 59, vs. 13 of 57 in the albendazole group; risk ratio, 1.63; 95 percent confidence interval, 0.91 to 2.92). More of the intracranial cystic lesions resolved in the albendazole group than in the placebo group. With the sole exception of abdominal pain, side effects did not differ significantly between the two groups. CONCLUSIONS: In patients with seizures due to viable parenchymal cysts, antiparasitic therapy decreases the burden of parasites and is safe and effective, at least in reducing the number of seizures with generalization.

Medical treatment of pulmonary hydatidosis: complications and surgical management.

Pulmonary hydatidosis is more frequently encountered in children than in adults. Chemotherapy with oral administration of particular antihelminthic agents (mebendazole and albendazole) has proved to be effective. This treatment, however, may be associated with serious complications that require surgical management. The aim of this study was to define the limitations of medical treatment, the subsequent complications, and their management. During a 16-year period (1985-2001), 36 children with pulmonary hydatidosis (Echinococcus cysticus) were medically treated. Oral antihelminthic agents (mebendazole until 1992 and albendazole thereafter) were given to all these patients. During this treatment, 11 patients developed complications requiring surgical intervention. In seven children, pleural empyema, or the presence of inflammatory residual fluid, was noted. The remaining four developed pulmonary abscess combined with fluid collection within the pleural cavity. In all complicated cases, the mean size of the cysts exceeded 6 cm in diameter at the beginning of medical treatment. At operation, suturing of communicating bronchi was insecure due to inflammation. Postoperatively, three patients had air leakage from the bronchial tree, requiring continuous suction and prolonged hospitalization. One patient presented with pneumothorax 4 months postoperatively and was operated on again. Overall, long-term results were good. We concluded that a) large pulmonary hydatid cysts should not be treated medically, b) incomplete expectoration of the cyst contents after the parasite death may lead to infection through bronchial communication, and c) patients surgically treated for complications following medical treatment are hospitalized twice as long as patients surgically treated in the first place.

Comparative clinical studies of nitazoxanide, albendazole and praziquantel in the treatment of ascariasis, trichuriasis and hymenolepiasis in children from Peru.

Three randomized clinical studies were conducted in 2000 to evaluate the efficacy of nitazoxanide paediatric suspension compared to albendazole in the treatment of ascariasis and trichuriasis and praziquantel in the treatment of hymenolepiasis in children from Cajamarca, Peru. Nitazoxanide was administered at a dose of 100 mg (age 1-3 years) or 200 mg (age 4-11 years) twice daily for 3 days, albendazole as a 400-mg single dose and praziquantel as a 25-mg/kg single dose. Post-treatment parasitological examinations were carried out on 3 faecal samples, each collected on a different day between 21 and 30 days following initiation of treatment. Nitazoxanide cured 89% (25/28), 89% (16/18) and 82% (32/39) of the cases of ascariasis, trichuriasis and hymenolepiasis respectively compared with 91% (32/35), 58% (11/19) and 96% (47/49) for the comparator drugs. Each of the drugs produced egg reduction rates in excess of 98%. There were no significant adverse events or abnormalities in haematology or clinical chemistry values or urinalysis.

Medical treatment for neurocysticercosis characterized by giant subarachnoid cysts.

BACKGROUND: Infection with the larval form of the pork tapeworm, Taenia solium, can lead to the development of cysts in the brain. Surgical removal of cysts has been the accepted treatment for neurocysticercosis characterized by giant cysts when there is associated intracranial hypertension. METHODS: We describe 33 patients whom we treated medically for malignant forms of neurocysticercosis. All patients had evidence of intracranial hypertension and subarachnoid cysts at least 50 mm in diameter. All patients received 15 mg of albendazole per kilogram of body weight per day for four weeks. Ten patients were also treated with 100 mg of praziquantel per kilogram per day for four weeks. Seventeen patients received a second course of albendazole, three received a third course, and one received a fourth course. During the first cycle of treatment, all patients also received dexamethasone. Five patients had previously undergone neurosurgery for giant cysts. RESULTS: After a median of 59 months of follow-up (range, 7 to 102), the condition of all 33 patients had improved, and the cysts had disappeared or become calcified. Of the 22 patients with a history of seizures, only 11 continued to receive antiseizure medications. The median quality-of-life score on the Karnofsky scale improved from 40 to 100. Fifteen patients received a ventriculoperitoneal shunt because of hydrocephalus. Four patients had persistent sequelae (bilateral partial optic atrophy, stroke, or diplopia) of the cysts. CONCLUSIONS: Intensive medical treatment can be effective in patients with neurocysticercosis characterized by giant cysts. Neurosurgery may be required only when there is an imminent risk of death.

Treatment of hydatid disease.

Hydatid disease caused by Echinococcus granulosus presents medical, veterinary and economic problems worldwide. Hydatidosis can be treated by medical, surgical and percutaneous modalities. Benzoimidazole carbamates are effective against E. granulosus. Although mebendazole, the first benzoimidazole used, has some beneficial effects on the disease in selected patients, it has also been associated with treatment failure in some cases, perhaps because of its poor absorption. Albendazole, a more recently developed benzoimidazole, is more effective than mebendazole. Praziquantel, an isoquinoline derivative, has recently shown value in the treatment of human echinococcal disease and its use in combination with albendazole is recommended in some patients. Ultrasound guided cyst puncture is another choice of treatment which has been used successfully in selected patients, although anaphylactic and allergic reactions due to spillage of the cyst contents have occurred. Surgical therapy in echinococcal hydatid disease is indicated for large cysts with multiple daughter cysts, superficially located single liver cysts which have a risk of rupture, complicated cysts such as those accompanied by infection, compression or obstruction, and cysts located in vital organs or which are exerting pressure on adjacent vital organs. However, surgical therapy carries high risk of mortality, morbidity or recurrence. Therefore, medical therapy may be an alternative option in uncomplicated cysts and in patients at high risk from surgery. The adjuvant use of drugs with surgery and percutaneous treatment can also be recommended for some patients.

The effects of albendazole solution at scolocidal concentration in the rat brain.

Intra-operative cyst rupture is a catastrophic event in the intracranial hydatid cyst disease. Dissemination of the cyst contents may lead to severe anaphylactic reactions and an increased risk of recurrence. Several scolicidal agents have been used to eradicate the infective scolices but recurrences occur and no solution has been evaluated for its adverse effects to the brain tissue. Being a specific scolocidal agent albendazole has been shown to be 100% scolicidal in vitro. In this study, we present the electrophysiological and histopathological effects of intracerebral 2% albendazole injection in the rat brain. Vascular, neuronal and glial as well as inflammatory changes were evaluated in order to detect any adverse pharmacological effects. Electrophysiological and most microscopic parameters showed no significant effects attributable to albendazole but in 25% of the albendazole group cerebral gliosis was detected whereas no gliosis was present in the control group. It is concluded that being a specific scolicidal agent albendazole offers an efficient alternative for ruptured cerebral hydatid disease, but the significance and clinical importance of the gliosis should be further investigated.

Sonographically guided percutaneous treatment of hepatic hydatid cysts: long-term results.

PURPOSE: The purpose of this study was to evaluate the safety and efficacy of sonographically guided percutaneous drainage and irrigation of hepatic hydatid cysts. METHODS: Sixty-one patients with 84 hepatic hydatid cysts were treated using the puncture, aspiration, injection, and reaspiration (PAIR) technique under sonographic guidance. Patients with cysts larger than 6 cm in diameter underwent PAIR followed by percutaneous drainage (PAIR-PD). The cysts were sterilized by the injection of 1 of 2 scolicidal agents, 20% hypertonic saline solution (38 patients) or 0.5% silver nitrate (23 patients). All patients underwent follow-up examinations for 1 month-6 years after aspiration. Clinical and radiologic examinations and laboratory analyses were performed every month for the first 6 months and then at 3-month intervals. RESULTS: Serial sonographic examinations revealed a heterogeneous echo pattern in 78 cysts (93%); a progressive decrease in diameter in 76 cysts (90%); calcification of the cyst wall, cystic contents, or both in 10 cysts (12%); and complete disappearance of 1 cyst (1%) in a patient who had been monitored for over 6 years. Five patients developed urticaria, and 6 developed fever. One patient developed a biliary fistula after the first aspiration attempt. Two patients developed infection of the cyst cavity after PAIR-PD and were successfully treated with oral antibiotics. An anaphylactic reaction developed in 2 patients and was successfully treated with antiallergenic medication. No recurrence of hydatid disease after PAIR or PAIR-PD was observed in any patient over the follow-up period of 72 months (mean, 26 +/- 27 months). CONCLUSIONS: Percutaneous drainage of hydatid cysts is a safe, effective, and reliable treatment. Antiallergenic medication is required before PAIR or PAIR-PD. Both sclerosing agents, hypertonic saline and silver nitrate solutions, gave excellent results.