Combination chemotherapy is more effective in postspillage prophylaxis for hydatid disease than either albendazole or praziquantel alone

Cationized albumin conjugated solid lipid nanoparticles as vectors for delivery of albendazole against cystic echinococcosis

BACKGROUND

Cystic echinococcosis (CE) is a common neglected parasitic disease. Nanoparticles containing drugs have been widely utilized in various formulations for several purposes, including improving the bioavailability of drugs by increasing the solubility and dissolution rate of the nanoparticles. The purpose of this study was to evaluate the effects of solid lipid nanoparticles containing albendazole and conjugated to albumin (B-SLN + ABZ) as a novel treatment approach for hydatid cysts in vivo.

METHODS

Albendazole-loaded solid lipid nanoparticles were prepared by emulsification and solvent evaporation method. The experimental mice were assessed for prophylactic and therapeutic effects of the drugs. Ultrastructural changes were observed by transmission electron microscopy.

RESULTS

The variance analysis of the fitted model indicated that the Glyceryl monostearate (GMS)/soy lecithin concentration ratio and the amount of albendazole had a significant effect on nanoparticle size. The GMS/soy lecithin concentration ratio and the amount of albendazole had a notable effect on nanoparticle polydispersity index (PdI) and entrapment efficiency (EE%), respectively. During chemoprophylaxis, the B-SLN + ABZ group showed a lower number and weight of cysts (0.90 ± 0.73 and 15.01 ± 10.46, respectively) compared with the ABZ + SLN group (1.4 ± 0.51 and 26.73 ± 9.92, respectively). In addition, therapeutic efficacy analysis showed a significant reduction in wet weights of metacestodes in mice treated with both B-SLN + ABZ (29.37 ± 13.82 mg) and SLN + ABZ (35.88 ± 7.49 mg) compared with the control group (59.78 ± 3.80 mg).

CONCLUSIONS

The results showed that B-SLN + ABZ nanoparticles were more effective against E. granulosus cysts compared with free ABZ. The cysts in the animals receiving B-SLN + ABZ every 24 h showed more ultrastructural changes.

A rare case of bilateral para-rectal hydatid disease: A case report

INTRODUCTION

Cystic hydatidosis is a parasitic infection caused by the organism Echinococcus Granulosus that is well known to be endemic in the Mediterranean region, eastern Europe and South America and usually presents as hydatid disease of the liver but may affect other organs. The disease occurs when humans become the accidental host through ingestion of the eggs from contaminated food.

CASE PRESENTATION

We present a case of Hydatid disease presenting as hives refractory to medical therapy over 4 years duration which was revealed to be caused by para-rectal hydatid cysts. Patient received Albendazole for a duration of 2.5 months and then underwent laparoscopic resection of the para-rectal cysts.

CLINICAL DISCUSSION

Pelvic Hydatidosis is a very rare condition accounting for 0.7 % of all cases reported. In most cases, it is coexistent with cysts present elsewhere in the body, namely the liver, which is the case in the presented patient. Imaging is used as a modality to establish the diagnosis of cystic hydatidosis namely Ultrasound (US), Computerized Tomography (CT) and Magnetic Resonance Imaging (MRI). The incidental finding of the hydatid cysts in this patient demonstrated the efficiency of a CT scan as a tool for detection and subsequently diagnosis of the disease in the pelvis. Surgery is the treatment of choice for cysts with daughter vesicles that are not candidates for percutaneous drainage, large liver hydatid cysts of more than 10 cm in diameter, cysts with a risk of rupture in case of trauma, and extrahepatic disease such as the lung, bone, brain, kidneys or pelvis.

CONCLUSION

This article reports the rare occurrence of para-rectal hydatid disease which is only described in few case reports in the literature and provides an overview on diagnosis, and management of the disease.

The Effects of Nitric Oxide and Inhibitor, and Combination of Albendazole and Praziquantel On Liver in Mice Injected with Echinococcus granulosus Larvae

In this study, the role of nitric oxide (NO) in the pathogenesis of hydatidosis and the interaction with effects of anthelmintic drugs, albendazole and praziquantel, were examined in larval infection caused by protoscolices obtained from hydatid cysts of sheep liver in Albino Balb/c mice. Animals were divided into ten groups including controls and infected groups. Larval infection was established with intraperitoneal injection of protoscolices. Eight months after infection with protoscolices, the infected animals were divided into 6 groups. The infected animals were given a selective inhibitor of inducible nitric oxide synthase (iNOS) L-N⁶-(1-Iminoethyl) lysine-hydrochloride (L-NIL), NO donor sodium nitroprusside (SNP), albendazole and praziquantel as anthelmintic drugs for 7 days. In addition, control groups were composed of intact group, control, anthelmintic drugs + L-NIL, and anthelmintic drugs + SNP. The liver and blood samples were taken for cytological, histological, immunohistochemical and biochemical analyses 7 days after treatments at the end of experiment. The animals injected with protoscolices showed histopathological changes including inflammation areas, infiltration and accumulation of leukocytes, dilation of sinusoids, and damage in endothelial cells and hepatocytes at light microscopy. Electron microscopy were revealed severe damage in sinusoidal endothelial cells, leukocytes especially eosinophils in sinusoid lumens and disorganization in endoplasmic reticulum and nuclear membrane. Endothelial nitric oxide synthase (eNOS) and iNOS reactions were increased in the tissue. Anthelmintic drugs decreased inflammation areas and damages; however, it did not change NOS reactions in the animals given protoscolices. L-NIL and SNP diminished both iNOS and eNOS reactions. Unlike the group administered the inhibitor, SNP treated group exhibited less inflammation areas. Combination of these substances and drugs resulted in decreased inflammation areas. eNOS and iNOS reactions decreased in the drugs and SNP administered group, while only iNOS reaction was decreased in L-NIL given infection group. In addition, the infected groups which received SNP displayed expanded sinusoids and hepatocytes with vacuoles, intriguingly. While levels of serum nitrite/nitrate elevated only in the infection group given drugs and SNP, it decreased in the L-NIL administered group. Tissue level of malondialdehyde increased in infection groups with drugs and SNP. In conclusion, the results indicated that NO plays an important role in the pathogenesis of hydatidosis.

Pulmonary Echinococcosis or Lung Hydatidosis: A Narrative Review

Background: Lung hydatidosis is a zoonosis related to infection by the Echinococcus tapeworm species. Lung involvement in this condition is second only to the liver echinococcosis. Diagnosis ordinarily results from an accidental finding in a direct chest radiograph evaluation because of the delayed growth of the cysts. Moreover, a consistent treatment regimen or approach may not be feasible because of the variability of pulmonary echinococcosis. In this review, we expect to sum up the main features of lung hydatidosis with a perspective on medical and surgical treatment. Methods: Cochrane Library and PubMed were the databases used to perform a narrative literature review. Search terms included "pulmonary echinococcosis" and "lung hydatidosis." The MeSH terms were "lung" [All Fields] AND {"echinococcosis" [MeSH Terms] OR ("hydatidosis" [All Fields] OR "pulmonary" [All Fields] AND "echinococcosis" [All Fields] OR "hydatidosis." A search period from September 1980 to May 2020 was chosen to compare studies from different decades, given the changes in pulmonary echinococcosis management. Results: A uniform treatment regimen or approach may not be feasible because of the variability of pulmonary echinococcosis. No clinical trials have analyzed and compared all the diverse treatment approaches. Cyst size, characteristics, position in the lung and clinical presentation, and the availability of medical/surgical expertise and equipment are the mainstays of echinococcosis management. When feasible, surgery is as yet the principal therapeutic choice to eliminate the cysts; anti-parasitic drugs may minimize complications during high-risk surgery or be used as definitive therapy in some instances with contraindications to surgery. Conclusions: Lung hydatidosis management must become less heterogeneous. We support treatment directed to the subject established on the clinical scenario, host factors, and surgical risk. Strict cooperation in this process between infectious disease specialists and surgeons may optimize best practices to help create shared practical guidelines to simplify clinicians' decision-making. Furthermore, we need a consensus for lung hydatidosis treatment and inserting this disease to global surgery agenda will have a positive impact on acquiring high-quality data that enables us to create an evidence-based guideline for this disease.

Current status of diagnosis and treatment of hepatic echinococcosis

Echinococcus granulosus (E. granulosus) and Echinococcus multilocularis (E. multilocularis) infections are the most common parasitic diseases that affect the liver. The disease course is typically slow and the patients tend to remain asymptomatic for many years. Often the diagnosis is incidental. Right upper quadrant abdominal pain, hepatitis, cholangitis, and anaphylaxis due to dissemination of the cyst are the main presenting symptoms. Ultrasonography is important in diagnosis. The World Health Organization classification, based on ultrasonographic findings, is used for staging of the disease and treatment selection. In addition to the imaging methods, immunological investigations are used to support the diagnosis. The available treatment options for E. granulosus infection include open surgery, percutaneous interventions, and pharmacotherapy. Aggressive surgery is the first-choice treatment for E. multilocularis infection, while pharmacotherapy is used as an adjunct to surgery. Due to a paucity of clinical studies, empirical evidence on the treatment of E. granulosus and E. multilocularis infections is largely lacking; there are no prominent and widely accepted clinical algorithms yet. In this article, we review the diagnosis and treatment of E. granulosus and E. multilocularis infections in the light of recent evidence.

Cysticidal Efficacy of Combined Treatment With Praziquantel and Albendazole for Parenchymal Brain Cysticercosis

BACKGROUND

The efficacy of current antiparasitic treatment for cerebral Taenia solium cysticercosis with either albendazole (ABZ) or praziquantel (PZQ) is suboptimal. A recent study demonstrated that combining these 2 antiparasitic drugs improves antiparasitic efficacy. We present here the parasiticidal efficacy data obtained during a previous phase II pharmacokinetic study that compared combined ABZ plus PZQ with ABZ alone.

METHODS

The study was a randomized, double-blinded, placebo-controlled phase II evaluation of the pharmacokinetics of ABZ (15 mg/k/d, for 10 days) and PZQ (50 mg/k/d, for 10 days) in intraparenchymal brain cysticercosis. Patients received the usual concomitant medications, including an antiepileptic drug (phenytoin or carbamazepine), dexamethasone, and ranitidine. Randomization was stratified by antiepileptic drug. Patients underwent safety laboratory evaluations at days 4, 7, and 11, as well as magnetic resonance (MR) imaging at 6 months to assess parasiticidal efficacy.

RESULTS

Thirty-two patients were included, 16 in each arm. All of them completed antiparasitic treatment and underwent follow-up brain MR imaging. Cysticidal efficacy was strikingly higher in the combined ABZ-plus-PZQ group than in the ABZ-alone group (proportion of cysts resolved, 78 of 82 [95%] vs 23 of 77 [30%] [relative risk {RR}, 3.18; 95% confidence interval {CI}, 2.08-4.88; P < .001]; patients with complete cyst clearance, 12 of 16 [75%] vs 4 of 16 [25%] [RR, 3.00; 95% CI, 1.23-7.34; P = .005]).

CONCLUSIONS

The combination of ABZ plus PZQ is more effective in destroying viable brain cysticercosis cysts than ABZ alone.

CLINICAL TRIALS REGISTRATION

NCT00441285.

Disseminated abdominal hydatidosis: a rare presentation of common infectious disease

Hydatid disease is one of the most geographically widespread zoonoses with substantial disease burden. In this report we are discussing an unusual case of intra-abdominal HD that was ongoing for 22 years despite two surgical interventions. Significant symptomatic relief was achieved within the first two months of combination therapy with albendazole and praziquantel. HD is still of public health concern in the Middle East that needs optimized care.

Efficacy of combined antiparasitic therapy with praziquantel and albendazole for neurocysticercosis: a double-blind, randomised controlled trial

BACKGROUND

Neurocysticercosis causes a substantial burden of seizure disorders worldwide. Treatment with either praziquantel or albendazole has suboptimum efficacy. We aimed to establish whether combination of these drugs would increase cysticidal efficacy and whether complete cyst resolution results in fewer seizures. We added an increased dose albendazole group to establish a potential effect of increased albendazole concentrations.

METHODS

In this double-blind, placebo-controlled, phase 3 trial, patients with viable intraparenchymal neurocysticercosis were randomly assigned to receive 10 days of combined albendazole (15 mg/kg per day) plus praziquantel (50 mg/kg per day), standard albendazole (15 mg/kg per day), or increased dose albendazole (22·5 mg/kg per day). Randomisation was done with a computer generated schedule balanced within four strata based on number of cysts and concomitant antiepileptic drug. Patients and investigators were masked to group assignment. The primary outcome was complete cyst resolution on 6-month MRI. Enrolment was stopped after interim analysis because of parasiticidal superiority of one treatment group. Analysis excluded patients lost to follow-up before the 6-month MRI. This trial is registered with ClinicalTrials.gov, number NCT00441285.

FINDINGS

Between March 3, 2010 and Nov 14, 2011, 124 patients were randomly assigned to study groups (41 to receive combined albendazole plus praziquantel [39 analysed], 43 standard albendazole [41 analysed], and 40 increased albendazole [38 analysed]). 25 (64%) of 39 patients in the combined treatment group had complete resolution of brain cysts compared with 15 (37%) of 41 patients in the standard albendazole group (rate ratio [RR] 1·75, 95% CI 1·10-2·79, p=0·014). 20 (53%) of 38 patients in the increased albendazole group had complete cyst resolution at 6-month MRI compared with 15 (37%) of 41 patients in the standard albendazole group (RR 1·44, 95% CI 0·87-2·38, p=0·151). No significant differences in adverse events were reported between treatment groups (18 in combined treatment group, 11 in standard albendazole group, and 19 in increased albendazole group).

INTERPRETATION

Combination of albendazole plus praziquantel increases the parasiticidal effect in patients with multiple brain cysticercosis cysts without increased side-effects. A more efficacious parasiticidal regime without increased treatment-associated side-effects should improve the treatment and long term prognosis of patients with neurocysticercosis.

FUNDING

National Institute of Neurological Disorders and Stroke (NINDS), National Institutes of Health.

Abdominal wall hydatid cyst: case report and review of literature

A 60-year-old woman presented with a swelling in right paraumbilical region of one-year duration. Examination revealed a painless cystic swelling 15 × 10 cm with cough impulse. Ultrasound and CECT abdomen showed a subcutaneous cystic swelling with intramuscular extension. No other intraabdominal cystic lesions were found. Surgical exploration showed a cystic lesion adherent to peritoneum without any intraperitoneal extension. Cyst was carefully excised without any spillage. Gross specimen on opening showed multiple daughter cysts consistent with hydatid cyst, confirming the diagnosis of solitary abdominal wall hydatid cyst.

Laparoscopic treatment of hepatic hydatid disease

BACKGROUND

  Hepatic hydatid disease is now rare in Australasia. However, it remains a significant problem in endemic areas. Many cases are now managed using minimally invasive techniques and this paper reviews the current status of laparoscopic approaches to hepatic hydatid disease.

METHODS

  A Medline data search was performed using the search terms of Ecchinococcos, laparoscopy, hepatectomy and pericystectomy. All publications from all publication years, including foreign language publications, were included.

RESULTS

  Eight series have been published comprising five or more patients, with most utilizing techniques of laparoscopic cystectomy. All series managed Gharbi cyst types I-IV, and median operative times were between 60 and 82 min. Seven conversions were reported (3%) for problems with access or bleeding. There was one reported fatality, and between 5% and 45% (median 13%) of patients developed complications. Three cases of anaphylaxis were reported and 14 cases of bile fistula were reported (median incidence: 6%). Hospital stays were between 3 and 10 days (median stay: 3.5 days). Two series report recurrences (recurrence rates of 3% and 4%) and these were in patients not treated with preoperative albendazole.

CONCLUSION

  Laparoscopic surgical techniques have been successfully applied to the treatment of hepatic hydatid cysts. While the uptake of these procedures is limited to areas of high prevalence and units with a specific interest, laparoscopic surgery is now one of the management options available to treat hepatic hydatid disease.

Pharmacokinetics of combined treatment with praziquantel and albendazole in neurocysticercosis

AIMS

Neurocysticercosis is the most common cause of acquired epilepsy in the world. Antiparasitic treatment of viable brain cysts is of clinical benefit, but current antiparasitic regimes provide incomplete parasiticidal efficacy. Combined use of two antiparasitic drugs may improve clearance of brain parasites. Albendazole (ABZ) has been used together with praziquantel (PZQ) before for geohelminths, echinococcosis and cysticercosis, but their combined use is not yet formally recommended and only scarce, discrepant data exist on their pharmacokinetics when given together. We assessed the pharmacokinetics of their combined use for the treatment of neurocysticercosis.

METHODS

A randomized, double-blind, placebo-controlled phase II evaluation of the pharmacokinetics of ABZ and PZQ in 32 patients with neurocysticercosis was carried out. Patients received their usual concomitant medications including an antiepileptic drug, dexamethasone, and ranitidine. Randomization was stratified by antiepileptic drug (phenytoin or carbamazepine). Subjects had sequential blood samples taken after the first dose of antiparasitic drugs and again after 9 days of treatment, and were followed for 3 months after dosing.

RESULTS

Twenty-one men and 11 women, aged 16 to 55 (mean age 28) years were included. Albendazole sulfoxide concentrations were increased in the combination group compared with the ABZ alone group, both in patients taking phenytoin and patients taking carbamazepine. PZQ concentrations were also increased by the end of therapy. There were no significant side effects in this study group.

CONCLUSIONS

Combined ABZ + PZQ is associated with increased albendazole sulfoxide plasma concentrations. These increased concentrations could independently contribute to increased cysticidal efficacy by themselves or in addition to a possible synergistic effect.

Optimal duration of preoperative anti-helminthic therapy for pulmonary hydatid surgery

BACKGROUND

The optimal duration of preoperative anti-helminths for prevention of recurrences in pulmonary hydatidosis is unclear, although 1-3 weeks of therapy is routinely used.

METHODS

Forty-five patients of pulmonary hydatid disease were randomly assigned into four groups to receive either 0, 2, 4 or 8 weeks of preoperative albendazole (ABZ) and praziquantel (PZQ). Viability of the scolices in the fluid harvested at surgery (methylene blue staining) and ability to produce peritoneal hydatids in mice (intra-peritoneal inoculation) were compared in different groups.

RESULTS

The percentage viability of the scolices as a whole was significantly (P < 0.001) lower in the treated cysts (n= 36, mean 43.5 +/- 35.69) compared with the untreated cysts (n= 8, mean 94.75 +/- 7.21). The viability progressively decreased with increasing durations of chemotherapy (P < 0.001). Mean percentage viability of scolices was 88.72 +/- 4.91% in patients treated for 2 weeks (n= 12), 38.09 +/- 9.10% after 4 weeks (n= 11) and 8.1 +/- 9.23% after 8 weeks (n= 14). Intra-peritoneal mice inoculation was positive in 90% of the cysts that received therapy for 2 weeks or less and none of the patients who received therapy for 8 weeks had a positive inoculation.

CONCLUSIONS

Preoperative combination therapy with ABZ and PZQ effects a scolicidal response which increases with the increasing duration of the preoperative chemotherapy, and a 4-week course of the combination chemotherapeutic agents seems to be the minimum required duration for ensuring scolicidal activity enough to prevent spillage-induced recurrences following pulmonary hydatidosis.

[Impossibility of the treatment of inoperable liver multicystic echinococcosis due to adverse reactions to antihelminitics]

INTRODUCTION

In some cases of multicystic forms of liver echinococcal disease, the advanced method for treatment of cystic echinococcosis faces great problems relating to the final outcome of the treatment.

CASE REPORT

In May 2005, a computerized tomography of the abdomen obtained in a 27-year-old female patient with abdominal pain revealed more than 20 echinococcal cysts measuring up to 6.7 cm in both lobes of the liver. Laboratory analyses found the value of eosinophils 6.8%, gamma globulins 29.9%, immunoglobulin E 29 600 IU/mL and the indirect hemagglutination for echinococcosis 1:8,196. The treatment started in December that year with the continuous administration of a daily dose of 800 mg (14.5 mg/kg body weight) of albendazole, but it was terminated two months later due to high serum transaminases values. By the end of 2006, the largest cyst detected in the left lobe of the liver had a diameter of 5.7 cm and the one in the right lobe of the liver measured 4.1 cm. There were lesions of germinative membrane found on both cysts. Six months later, praziquantel at daily dose of 2,500 mg (45.3 mg/kg body waight) was introduced into the therapy, but the treatment was terminated after eight days because of the development of exanthema. The computerized tomography of the abdomen obtained in February 2008 revealed the presence of a large number of echinococcal cysts in the liver. The largest among those cysts measured 3.5 cm while calcifications of the cyst walls were observed on some of them. None of the remaining therapeutic options for further treatmetnt of echinococcal disease could be applied.

CONCLUSION

The presented case confirms medical therapy as the only option for the treatment of some forms of cystic echinococcosis. Benzimidazole carbamates (albendazole, mebendazole) and praziquantel are only efficacious antihelminitics currently available, and when they have to be withdrawn due to serious adverse affects, futher treatment of a patient with liver multicystic echinococcosis is impossible. Because of that there is a need to search for new and more efficient drugs for the treatment of ehinococcal disease.

Praziquantel: neglected drug? Ineffective treatment? Or therapeutic choice in cystic hydatid disease?

The role of praziquantel in hydatid disease has not been well defined. This review evaluates the evidence on the use of praziquantel in treatment of cystic hydatid disease from in vitro and in vivo animal studies, human clinical studies and case reports. Praziquantel may prevent the vesicular evolution of protoscoleces and inhibit the formation of secondary cysts. It may also contribute to the loss of viability of small cysts before cyst differentiation and development of the fibrous adventitial layer. There is some evidence to support a role for the use of praziquantel in combination with albendazole in pre- and post-intervention chemotherapy for hydatid disease. Combined therapy may reduce the risk of disease recurrence and intraperitoneal seeding of infection that develops via cyst rupture and spillage occurring spontaneously or during surgery or percutaneous procedures. At present, there is insufficient published evidence to support a clear recommendation for the use of praziquantel in prolonged chemotherapy for established hydatid disease for which surgery is not indicated or in severe disseminated disease and further work is necessary. Randomised controlled studies to determine the efficacy and optimum duration of praziquantel treatment in combination with albendazole are required so that treatment recommendations for its use can finally be clarified.

Cardiac involvement of hydatid disease

OBJECTIVES

Echinococcosis is a serious health issue occurring in some geographical region of the world. Cardiac involvement is rare and early diagnosis and prompt surgical intervention are critical.

SUBJECTS AND METHODS

Six patients with cardiac hydatid cysts underwent surgical treatment in our institution between April, 1996 and March, 2002. Five of the patients were female and one was male. Average age was 40+/-5 years with a range of 19 to 72 years. Cysts were located in the right ventricular outflow tract in two patients, the left ventricular outflow tract in one, the right atrial in one, the right ventricular in one and the right atrioventricular groove in one. Five patients were operated on using standard cardiopulmonary bypass techniques, and one was operated on without cardiopulmonary bypass.

RESULTS

In the perioperative and the early postoperative period, no cardiac problems was observed. On control echocardiography, a ventricular septal defect was detected in one patient in the late postoperative period. The ventricular septal defect was repaired using standard cardiopulmonary bypass and was closed with a teflon patch. Patients were followed up for a mean period of 3.4+/-2.5 years. No mortality or recurrence was observed during the follow-up period.

CONCLUSIONS

When hydatid cyst is diagnosed, the possibility of cardiac involvement should also be investigated. The treatment of cardiac hydatid cyst is surgical extraction of the cyst. Results of surgery are generally satisfactory.

Benzimidazole treatment of cystic echinococcosis

Hydatidosis (cystic echinococcosis, CE) constitutes a serious public health problem worldwide. Total surgical removal of a hydatid cyst is still considered the gold standard treatment for CE. Percutaneous treatment (PAIR), using either hypertonic saline or alcohol as a larvacidal agent, appears to be an additional effective form of treatment. Benzimidazoles (albendazole, ABZ; mebendazole, MBZ), given either alone or combined with praziquantel (PZ) are currently used for the treatment of non-surgical cases and as a supplementary treatment prior and post-surgery. Combined chemotherapy was found to be more effective than either of the agents given alone. ABZ is easily absorbed and more effective than MBZ. ABZ (12-15 mg/kg/day) and MBZ (30-70 mg/kg/day) given for 14-20 days prior to surgery and continued for an additional 3-24 months in a cyclic monthly form were found effective against the disease. Either increased or decreased circulating antigen levels, which consequently cause changes in the humoral (IgG, IgG1, IgG4, IgE) immune responses, have a prognostic value in successfully treated CE cases. However, although the cellular immune response to echinococcal antigens decreased in improved or cured CE patients, it was not considered of practical use in determining treatment efficacy. In certain cases successful treatment was also followed by elevated eosinophilia and erythrocyte sedimentation rates. In the present article, the mechanism of drug activities as well as the development of resistance against the drugs available are further discussed.

Hydatid lung disease (echinococcosis/hydatidosis)

Two Echinococcus species may exhibit medical relevance as causative agents of pulmonary forms of echinococcosis. Most importantly, infections with Echinococcus granulosus result in "cystic hydatid disease" or "cystic echinococcosis," which affects the lungs in a considerable ratio of cases. Echinococcus multilocularis, which causes "alveolar echinococcosis," affects the lungs relatively rarely and then usually upon metastasizing from primary hepatic lesions. Cystic echinococcus and alveolar echinococcus differ pathologically and clinically so greatly that they are considered separately in this article, although alveolar echinococcus is covered minimally because of its minor importance regarding lung infections.

Primary muscle hydatidosis of the thigh: management of a complicated case with combination adjunctive albendazole and praziquantel chemotherapy

A patient had primary muscle hydatidosis of the thigh that was not detected radiologically or by fine-needle aspiration before surgery. The risk of dissemination during the initial exploratory procedure was high. Treatment consisted of formal muscle resection and combination therapy with albendazole and praziquantel. Clinical features of muscle hydatidosis and the role of adjunctive chemotherapy are reviewed.

Orbital hydatid cyst: treatment and prevention of recurrences with albendazole plus praziquantel

A case of successful treatment of orbital echinococcosis without evidence of recurrence on prolonged follow-up is presented. The management of orbital hydatid cyst is discussed. ¿ 2000 The British Infection Society

[Cardiac hydatid cyst in a child]

Cardiac hydatid cyst is an uncommon disease, especially in children. The interventricular septum region is the most frequent localization. The cysts usually involve other organs making the etiologic diagnosis easier. Our young patient presented a single hydatid cyst. The etiologic diagnosis was difficult due to the negativity of the serologic tests and there were no other organs affected. Surgical ablation of the cyst was performed and histopathological analysis achieved.

Cestodes. Echinococcus

This article deals with cystic echinococcosis (CE) and alveolar echinococcosis in humans caused by the cestode parasites Echinococcus granulosus and Echinococcus multilocularis. The life cycles of these parasites and their epidemiologic aspects are briefly discussed, and a detailed review is presented on clinical aspects of the diseases, including diagnosis and therapy. Considerable progress has been made in chemotherapy but the results are not yet satisfactory. A new alternative for treatment of CE is puncture of cysts, aspiration of fluid, injection of ethanol, and reaspiration of fluid (PAIR).

Sacrococcygeal hydatid cyst: another entity in the differential diagnosis of sacrococcygeal chordoma. Case report

A case of hydatid disease of the sacrum with severe neurological symptoms, which was misdiagnosed preoperatively as a chordoma, is presented. The patient had significant improvement of the neurological symptoms after evacuation of the cyst. Sacral hydatid cysts must be considered in the differential diagnosis of sacrococcygeal chordoma.

Unusual presentations of cerebral hydatid disease in children

Three children with hydatid disease of the central nervous system (CNS) were seen. In two patients the lateral ventricles were involved, whilst one case involved the cerebellar hemisphere. In addition, one child presented with a deposit in the maxillary antrum, and deposits were also found in the liver. Operative removal of the deposits was performed, followed by post-operative treatment with praziquantel and albendazole. Investigation of other sites outside the CNS was undertaken for occult lesions. All hydatid cysts were clearly demonstrated on CT, but two cases posed the pre-operative problem of differential diagnosis from arachnoid cysts.