Puncture, Aspiration, Injection, Re-aspiration Research Articles

Treatment Options and the Management of Complications in Hydatid Cysts of the Liver in Endemic Regions.

Hydatid cyst of the liver induced by Echinococcus granulosus is a pervasive zoonotic disease in our region. Its incidence varies across age groups, contingent on community lifespans and hygiene standards. Therapeutic modalities include Puncture, Aspiration, Injection, Re-aspiration (PAIR), and surgery. Due the limited feasability of PAIR, we suggest that surgery represents the optimal treatment in all stages, especially in endemic regions, depending on patient-specific variables. Patients with hydatid cyst of the liver treated with PAIR and surgery in our center between January 2016 and January 2022 were analyzed retrospectively. PAIR or cystectomy were applied in treatment. These were then compared in terms of efficacy, feasibility, and complications. A single hydatid cyst of the liver was detected in 184 of the 225 cases, two cysts in 33, and three or more cysts in eight. The largest cyst diameter was 233 × 124 mm in the surgery group and 100 × 90 mm in the PAIR group. One hundred thirty-three of the 225 patients underwent open surgery, and no recurrence was encountered in these. However, recurrence was observed 19 patients treated with PAIR. Allergic reaction developed in one case during surgery, postoperative abscess in two cases, biliary fistula in five, and pneumonia in one. Surgical treatment should represent the standard procedure since it is safe and effective, ensures complete elimination of the parasite, involves no intraoperative shedding, preserves healthy tissues, and minimizes the risk of long-term recurrence and cavity-related complications.

What are the Strategies for Controlling Hydatid Cysts in Developing Countries?

Hydatid cysts (HC), caused by the tapeworm of the genus Echinococcus, pose a significant public health challenge in many developing countries. These cysts primarily affect livestock, such as sheep, cattle, and goats, but can also infect humans, the two most important forms in humans are cystic echinococcosis (hydatidosis) and alveolar echinococcosis, leading to serious health complications. Control measures for HC are crucial to lessen the impact on both human and animal health. This editorial explores the possible strategies for controlling HC in developing countries, focusing on prevention, surveillance, treatment, and community education [1,2]. Preventing HC in developing countries may require a multifaceted approach. One crucial aspect is controlling the transmission of Echinococcus eggs from infected animals to humans. This involves implementing measures such as deworming programs for livestock, proper disposal of infected animal carcasses, and promoting good hygiene practices among livestock handlers and population Furthermore, community education plays a vital role in preventing HC. Educating individuals about the risks associated with handling infected animals, the importance of proper hand hygiene, and the benefits of cooking meat thoroughly can help reduce the transmission of the parasite [2]. Effective surveillance is essential for monitoring the prevalence of HC and identifying high-risk areas in developing countries. Surveillance systems should involve regular screening of both livestock and humans for Echinococcus infection. This can be achieved through the use of diagnostic tests such as serological assays and imaging techniques like ultrasound. Additionally, active surveillance programs can help detect outbreaks early and facilitate timely intervention measures. Collaborative efforts between government agencies, healthcare providers, and veterinary professionals are crucial for establishing robust surveillance systems in resource-limited settings [3, 4]. Treating HC in developing countries often presents challenges due to limited access to healthcare resources and diagnostic tools. However, prompt diagnosis and treatment are essential to prevent complications such as cyst rupture and dissemination. Surgical intervention remains the primary treatment option for HC, involving the removal of the cysts and surrounding tissue. In some cases, minimally invasive techniques such as puncture–aspiration–injection–re-aspiration (PAIR) may be used as an alternative to surgery, particularly in resource-limited settings. In addition to medical treatment, access to safe and effective anthelmintic drugs is crucial for controlling HC. Ensuring the availability of these medications and training healthcare providers in their appropriate use are essential components of treatment strategies in developing countries [5,6]. Educating communities about HC, their transmission, and prevention measures might play a significant role in sustainable control efforts. This can be achieved through various educational initiatives, including workshops, community outreach programs, and the distribution of educational materials. Furthermore, engaging with local community leaders and healthcare providers can facilitate the adoption of preventive measures within communities. Emphasizing the importance of early detection, timely treatment, and proper hygiene practices can empower individuals to take proactive steps in protecting themselves and their livestock from HC. In conclusion, controlling HC in developing countries requires a comprehensive approach that addresses prevention, surveillance, treatment, and community education. By implementing targeted interventions and fostering collaboration between government agencies, healthcare providers, community stakeholders, and the scientific community However, extensive research and investigations in this regard are highly recommended.

Genotyping of Echinococcus granulosus Human Isolates Obtained from the Puncture, Aspiration, Injection, and Re-Aspiration (PAIR) Process in Türkiye.

Echinococcus granulosus is spread by the excretion of cystic organs into the environment. The dog is infected via eating the cystic organ. It then contaminates the environment with eggs of E. granulosus, which are infective to humans and animals. We aimed to determine the E. granulosus genotypes that cause infection in humans in the Van region, Türkiye. Sixty patients between 18 and 100 years of age, who underwent the puncture, aspiration, injection, re-aspiration (PAIR) procedure in the Department of Radiodiognastics of Van Yüzüncü Yıl University, Van, Türkiye were included in the study. PAIR fluids were examined microscopically and DNA was isolated from the fluids. After DNA isolation, polymerase chain reaction (PCR) was performed using primers that amplify the E. granulosus NADH dehydrogenase subunit 1 (NAD1) gene region. After sequence analysis of the PCR amplicons, Basic Local Alignment Search Tool (BLAST) was performed. In the microscopic examination, protoscolex or hook was detected in 42 (70%) of the samples. DNA was successfully extracted from all of the cyst fluids containing protoscolex and hook, and the NAD1 gene region was PCR-amplified. After using BLAST, all of the samples were determined to be an E. granulosus sensu stricto G1 genotype. Sequence comparison revealed that four (9.5%) isolate sequences showed single nucleotide polymorphism (SNP). Sequences of isolates with SNP submitted to the GenBank with accession numbers OR565864 to OR565867. E. granulosus s.s. G1 genotype, known as sheep strain, is common in human hydatid disease in the Van region of Türkiye.

Sudden Hairloss and COVID-19

A woman, 51 years old with known hypothyroidism, was admitted to the emergency service because of postoperative complaints of nausea, vomiting, and jaundice. The patient's imaging revealed pleural effusion, compression atelectasis in the right lung, and lesions compatible with type 2 hydatid cysts in the liver; therefore, PAIR (Puncture, Aspiration, Injection, Reaspiration) was planned, and she was admitted to the internal medicine service. After this, the routine COVID PCR, taken before the interventional procedure, was found positive. During the patient's follow-up, there were no indications of respiratory failure brought on by a COVID infection. Although her vitals were steady, it was noted that she had an intense headache, and frequent and severe hair loss from night to morning on the third day of hospitalisation due to a contagious infection.
 There are few photos about similar cases. This case also important to be recognized as a symptom/complication of COVID-19 to be managed.

An unsolved problem in developing countries: hydatid cysts in children.

Hydatid cyst (HC) is a serious health problem in developing countries. The aim is to discuss the clinical information, surgical and puncture-aspiration-injection-re-aspiration (PAIR) treatments, and results of patients with HC in a developing country. Patients were analyzed in terms of gender, age, presenting complaint, misdiagnosed HC, cyst location, cyst number, cyst size, liver HC type according to the World Health Organization Informal Working Group Echinococcosis (WHO-IWGE) classification, pulmonary HC, hemithorax locations, treatments and interventions, duration of hospitalization, follow-up period, postoperative complications, and recurrence. There were 106 girls and 99 boys with a mean age of 10.7years. The most common location was the liver (n = 170), and the second most common was the lungs (n = 67). The mean diameter for liver HC was 86.27mm, and it was 73.90mm for pulmonary HC. PAIR was performed on 61 patients with liver HC using interventional radiology. 109 patients underwent surgery. The most common complications were cystobiliary fistula in liver HC and atelectasis in pulmonary HC. HC should be one of the first considerations in the differential diagnosis in all anatomical areas in the presence of suspicious radiological and clinical findings in endemic regions.

Renal Cystic Echinococcosis: Long-Term Outcomes of Percutaneous Treatment

PurposeTo evaluate the long-term outcomes of percutaneous treatment of renal cystic echinococcosis (CE) stratified by cyst stages according to the World Health Organization (WHO) classification. Materials and MethodsBetween January 1997 and February 2019, 34 patients with renal CE (18 women; mean age, 38 years) were treated with 3 different percutaneous techniques. According to the World Health Organization classification, the cysts were classified as CE1, CE2, CE3a, and CE3b. Puncture, aspiration, injection, reaspiration (PAIR) or standard catheterization was used for the dimension-based treatment of CE1 and CE3a cysts. Modified catheterization (MoCaT) was used to treat all CE2 and CE3b cysts. Technical and clinical success, complications, and reduction in cyst cavities were evaluated. ResultsThe technical success rate was 100%. PAIR, standard catheterization, and MoCaT were used to treat 12, 9, and 13 cysts, respectively. The only severe adverse event was a bacterial superinfection that occured in the cyst cavity of a patient (3%) treated with MoCaT. Four patients (12%) experienced mild/moderate periprocedural allergic adverse events and were managed conservatively. The mean length of hospital stay was 1, 5, and 7 days for patients treated with PAIR, standard catheterization, and MoCaT, respectively. The clinical success rate was 97%. In 1 of 34 cysts (3%), recurrence was detected and the cyst was successfully re-treated. During the 10.5-year follow-up period, 95% volume reduction was achieved. The median final cyst volume was 10 mL. ConclusionsRenal CE can be successfully treated with minimum adverse events and recurrence rates using appropriate percutaneous techniques selected according to their stages as classified according to WHO.

A review of the diagnosis and management of liver hydatid cyst.

Hydatidosis is a zoonosis caused by Echinococcus in the larval stage. Humans are accidental intermediary hosts where cystic lesions develop, primarily in the liver and the lungs. It is usually asymptomatic, hence it often represents an incidental finding. Symptoms result from cyst expansion and/or host inflammatory reaction. Hepatomegaly is the most common sign. Hydatidosis induces no specific changes in lab tests but immunodiagnostics are available that may complement its study, with antibody detection being the modality of choice. While ultrasound is the main diagnostic technique, tomography offers more accurate information regarding both characteristics and anatomical relations. A number of therapy options are presently available. Treatment with albendazole, whether combined or not with praziquantel, is useful for smaller, uncomplicated cysts (< 5 cm). Only 30 % of cysts disappear with medical treatment alone. Surgery is indicated for bigger liver cysts (> 10 cm), and cysts at risk of rupture and/or complicated cysts. The laparoscopic approach is scarcely widespread. The radical technique (total cystopericystectomy) is preferable because of its lower risk for postoperative abdominal infection, biliary fistula, and overall morbidity. Conservative techniques are appropriate in endemic areas where surgery is performed by nonspecialist surgeons. PAIR (puncture-aspiration-injection-reaspiration) is an innovative technique representing an alternative to surgery. It is indicated for inoperable cases and/or patients who reject surgery, for recurrence after surgery, and for lack of response to medical treatment. Active surveillance without treatment may be indicated for quiescent or inactive, uncomplicated liver cysts.

S2565 An Incidental Liver Mass Waiting to Explore: Hydatid Cyst in a Pregnant Female

INTRODUCTION: Human echinococcosis is a disease process caused by several species of tapeworms in the Echinococcus genus. These tapeworms utilize a variety of hosts that include rodents, herbivores and carnivores; humans are considered accidental hosts. This disease is very uncommon in the United States, and manifests most commonly with cystic liver lesions; but can spread to other organs as well. The liver cysts are slow growing and asymptomatic until they exceed 10 cm in size. Diagnosis is made with imaging and serologies. Here we present a case of a hydatid cyst in a pregnant female, with limited treatment options. CASE DESCRIPTION/METHODS: A 40 year old healthy Lebanese female, G3P2 at 11 weeks, presented with left lower extremity edema, dizziness and leg pain. Lower extremity ultrasound (US) revealed extensive thrombus, with subsequent CTPA revealing bilateral pulmonary emboli. Incidentally, a 7.1 cm hepatic mass was noted on the CTPA. Labs revealed a normocytic anemia with a hematocrit at 30.9% but were otherwise normal including liver function studies. Anticoagulation with enoxaparin was started, and she was transferred to a tertiary medical center for evaluation of the liver mass. There, she underwent a dedicated ultrasound of her abdomen which demonstrated a 7 cm mother cyst with multiple daughter cysts consistent with a hydatid cyst (Figure 1). Serological markers were sent and revealed a positive echinococcus antibody. Due to patient remaining asymptomatic and her gravid status; active surveillance was pursued. She underwent hepatic US every 3 months until delivery of a healthy girl. Over the course of her pregnancy, the cyst marginally increased in size, but her liver function tests remained normal and she remained asymptomatic. Post-partum, she underwent a modified puncture-aspiration-injection-reaspiration (PAIR) procedure. DISCUSSION: Hydatid cysts can result in pain, pancreatitis, rupture with further seeding, hemorrhage, fistula formation and systemic infection. These cysts can cause mass effect with compression of the biliary tree and portal vessels. The differential includes abscess, hemangioma, hamartoma and malignancy. Surgical treatment with adjunctive antiparasitic therapy can be utilized, but percutaneous therapy tends to have shorter hospital stays. Given the rarity of this disease in the United States and limitation of treatment during pregnancy; hydatid cysts should be considered in the differential of hepatic mass and actively monitored during pregnancy.Figure 1.: Abdominal Ultrasound.

An old drug as a promising new cure for the hard-to-treat echinococcosis

An old drug as a promising new cure for the hard-to-treat echinococcosis

Current trends in the management of hydatid disease: Surgeons' perspective

Background: Surgery was the only known curative treatment for hydatid disease. Currently, this is being changed. Aims: The aim of this study was to explore the evolution of our management policy for hydatid disease. Patients and Methods: We retrieved records of patients with hydatid disease, treated in our unit in the period from January 1998 to February 2012. Results: Twenty-seven patients were identified. For comparison and driven by the appearance of nonsurgical means in the series, patients were divided into two groups: the first group included the first 12 patients and the second group included the last 15 patients. In the first group, all patients received surgery and only two (16.7%) received postoperative albendazole therapy. In the second group, only four patients (26.7%) received surgery with perioperative pharmacotherapy, eight patients (53.3%) received pharmacotherapy alone, and three patients (20%) received puncture-aspiration-injection-reaspiration (PAIR) with periprocedural pharmacotherapy. In those who received surgery with adjuvant pharmacotherapy, one patient died and the cyst disappeared in the remaining three. In those who received PAIR, the cyst disappeared in one case and regressed in the other two. In those who received pharmacotherapy alone, two patients showed disappearance of the cyst, one showed partial response, and five are under follow-up. Conclusions: Surgery is no longer the first-line treatment for hydatid disease. It should be reserved for complicated cases and those presenting as an emergency. When applied, surgery should be backed by pharmacotherapy which has a pivotal role, both as a sole agent and as an adjunctive to therapy.

493 - Extrahepatic Pelvic Echinococcal Cysts Managed with Laparoscopic Puncture, Aspiration, Injection, Re-Aspiration (PAIR) and Cyst Excision

493 - Extrahepatic Pelvic Echinococcal Cysts Managed with Laparoscopic Puncture, Aspiration, Injection, Re-Aspiration (PAIR) and Cyst Excision

Modern role of clinical ultrasound in liver abscess and echinococcosis.

In the Western world, liver abscesses are predominantly of pyogenic origin and can present a wide range of ultrasonographic features, from a solid mass to a cystic cavity. Amoebic abscesses are endemic in tropical areas and typically round single lesions. Echinococcal cyst is diagnosed by ultrasound (US). Serology is particularly useful when pathognomonic US features are absent. Treatment is determined based on the WHO ultrasonographic classification, and puncture, aspiration, injection, re-aspiration (PAIR) is a US-guided therapeutic option. Hepatic alveolar echinococcosis presents on US as a pseudotumoral mass frequently with calcifications that may invade the biliary tree and portal and hepatic veins.

An Alternative Method for Percutaneous Treatment Of Hydatid Cysts: PAI Technique

Surgery is still the first choice in complicated cystic echinococcosis. However, percutaneous methods have performed increasingly in recent years. The Puncture, Aspiration, Injection, Reaspiration (PAIR) technique is mostly the preferred percutaneous method. The Puncture, Aspiration, Injection (PAI) technique is the new modified method, which is differentiated from PAIR technique by its applicability to all types of hydatid cysts (types 1-5) and unperforming of reaspiration. The 52 hydatid cysts were prospectively examined in the study. Thirty-four of them were Types I and II, 13 of them were Type III, and 5 of them were Types IV and V. The technique was performed using the 20 G Chiba needle under the guidance of ultrasonography. Maximum cyst contents were aspirated immediately after the puncture to reduce the intracystic pressure. After confirming that aspirated liquid does not contain bile and that cyst has no cystobiliary connection, 95% alcohol was injected into the cavity, safely. Reaspiration of alcohol was not performed. The cyst sizes were reduced after PAI on ultrasonographic evaluations in all cases. The liquid component disappeared and the cyst got solid characteristic three months after the procedure. All hydatid cyst types can be treated safely and effectively with PAI technique without considering dimensions and whether.

Cystic Echinococcosis in Childhood: Five-Years of Experience From a Single-Center

To evaluate the clinical data and prognosis of cystic echinococcosis during a 5-year period who were followed by the pediatric clinics. Demographic, clinical, laboratory, and prognosis data of 34 patients with cystic echinococcosis obtained between 2009 to 2014 were retrospectively evaluated. Of these, 10 patients were excluded because of incomplete data or failure to follow up. A total of 24 (12 males and 12 females) children were included the study. The mean ages of patients were 11.17 ± 3.71 (range, 5-17) years. The most common symptoms were abdominal pain (41.7%), cough (16.7%), and fatigue (12.5%). Localization of the parasite in the patients was determined to be as follows: liver (54.2%), lung (33.3%), and intraabdominal (4.2%). Multiorgan involvement was observed in 8.3% of the cases. Indirect hemagglutination test was positive in 13 (54.2%) patients at admission. All patients received treatment with albendazole. Seven patients were treated with puncture-aspiration-injection-re-aspiration (PAIR) (29.2%). Open surgery was performed in six patients (24.2%). One patient was treated with both PAIR and open surgery. Cystic echinococcosis is a serious public health problem in developing countries. Hydatid cyst should be considered in the presence of suspicious radiological and clinical findings in endemic areas.

Non-surgical and non-chemical attempts to treat echinococcosis: do they work?

Cystic echinococcosis (CE) and alveolar echinococcosis (AE) are chronic, complex and neglected diseases. Their treatment depends on a number of factors related to the lesion, setting and patient. We performed a literature review of curative or palliative non-surgical, non-chemical interventions in CE and AE. In CE, some of these techniques, like radiofrequency thermal ablation (RFA), were shelved after initial attempts, while others, such as High-Intensity Focused Ultrasound, appear promising but are still in a pre-clinical phase. In AE, RFA has never been tested, however, radiotherapy or heavy-ion therapies have been attempted in experimental models. Still, application to humans is questionable. In CE, although prospective clinical studies are still lacking, therapeutic, non-surgical drainage techniques, such as PAIR (puncture, aspiration, injection, re-aspiration) and its derivatives, are now considered a useful option in selected cases. Finally, palliative, non-surgical drainage techniques such as US- or CT-guided percutaneous biliary drainage, centro-parasitic abscesses drainage, or vascular stenting were performed successfully. Recently, endoscopic retrograde cholangiopancreatography (ERCP)-associated techniques have become increasingly used to manage biliary fistulas in CE and biliary obstructions in AE. Development of pre-clinical animal models would allow testing for AE techniques developed for other indications, e.g. cancer. Prospective trials are required to determine the best use of PAIR, and associated procedures, and the indications and techniques of palliative drainage.

Effectiveness of Puncture-Aspiration-Injection-Reaspiration in the Treatment of Hepatic Hydatid Cysts

BackgroundHydatid disease of the liver is endemic in cattle rearing areas of the world. A variety of treatment options are available in its management. The common treatment options are medical therapy, surgery and puncture-aspiration-injection-reaspiration (PAIR) therapy.ObjectivesThis study was performed to evaluate the effectiveness of PAIR therapy in the treatment of hepatic hydatid disease.Patients and MethodsThis cross sectional study was carried out on 15 consecutive patients (Male: 2, Female: 13; Age group: 11-80 years) with hepatic hydatid disease and were treated by PAIR therapy and followed up for a period of 1 year. The cysts were punctured under local anesthesia with an 18G needle using sonographic guidance. Betadine (10% povidone iodine + 1% free iodine) was used as scolicidal agent and allowed to act for 30 min. Cysts larger than 5 cm (n = 5) were drained using an 8F pig tail catheter. The therapeutic response was studied by assessing the reduction in the cyst size, progressive solidification of the cyst, calcification of the wall and increase in the echogenicity of the cyst with pseudomass appearance on serial ultrasound examinations performed on the next day, after 1 month, at 3 months, 6 months and 1 year after the procedure.ResultsTen patients (66.7%) had Gharbi type I cysts, two (13.3%) had type II and three (20%) had type III cysts. All the patients (100%) showed reduction in cyst size over a 3-6 month period. Pseudomass appearance with solidification was seen in 73% of the patients and calcification was seen in 46.6%. None of the patients developed anaphylaxis, recurrence or peritoneal seedlings. Pain at the injection site was the most common complication observed.ConclusionPAIR therapy is an effective minimally invasive treatment for Gharbi type I-III hepatic hydatid cysts. It is a cost effective and safe procedure with significant reduction in the duration of hospital stay.

Hydatid Cyst of the Spleen: Tunisian Series of 21 Cases.

Hydatid disease is a parasitic infection caused by Echinococcus granulosus. Splenic involvement is rare even in endemic areas. The aim of this study is to specify epidemiologic features, diagnostic tools, and therapeutic modalities of this uncommon entity. This is a retrospective study of 21 patients operated on for a splenic hydatid cyst between January 1996 and December 2011. The mean age was 43.8years (range 15-72years). Sixteen patients (76.2%) had symptoms related to a splenic location of hydatid disease. While splenic hydatid disease was solitary in 8 patients (38.1%), other locations were present in 13 patients (61.9%), mainly in the liver. Most splenic cysts were type I (39.3%) or III (42.8%). Nine patients (42.8%) underwent resection of the protruding dome with one postoperative complication (suppuration of residual cavity). Total and partial splenectomies were performed in nine and three patients, respectively, without any complication. No death was noted. After a mean follow-up period of 36months (range 2-108months), no recurrence was observed. Splenic hydatid cyst is a rare location. The diagnostic is usually easy, based on serology and imaging. The surgery is the mainstay of treatment. The type of surgical procedure depends on size, number, and location of the cyst. Total splenectomy is more effective but may have high morbidity and mortality and must be reserved to specific situations. Conservative procedure is safer but could increase the rate of recurrence and postoperative collection. Puncture aspiration injection reaspiration could be proposed for small cyst in inoperable patients.

Cystic Echinococcosis: With Emphasis on Treatment Options

[1, 2]. It causes characteristic cystic lesions most commonly found in the liver and lungs, but it can arise anywhere in the body [3,4]. Humans as accidental or aberrant intermediate host are infected either by direct contact with dogs or by consumption of water or foods contaminated with feces of dogs containing eggs of parasite [4,5]. Although CE is endemic in developing and tropical countries in South America, Africa, Mediterranean countries and the Middle East, it has a worldwide geographical distribution [2,4,6]. The diagnosis is made by a set of diagnostic methods including certain serologic and laboratory tests including immunofluorescency (IF), enzyme-linked immunosorbent assay (ELISA), and imaging or scanning techniques such as abdominal ultrasound (US), X-ray, computed tomography (CT) and magnetic resonance imaging (MRI) [7-10]. When hydatid disease is diagnosed, treatment should be performed to prevent complications such as secondary infection, rupture of the cyst to adjacent tissues, rupture with intraperitoneal dissemination of the disease, anaphylactic reaction, and pressure on adjacent organs [9]. The treatment of hydatidosis relies on some options such as chemical or medical therapy, surgery and puncture aspiration injection reaspiration [6,11]. In cases of the difficult accessibility to the lesion, the poor condition of patient for surgery, aged and pregnant patients, dead or calcified cysts, very small cysts, and inoperable patients with multiple cysts in two or more organs, medical treatment including benzimidazoles (mebendazole and albendazzole) or praziquantel are suggested [9-11]. Albendazole sulfoxide loaded solid lipid nanoparticles (SLN) has been introduced as an efficient therapeutic regimen in treating hydatidosis in animals and humans [6]. It has been shown that warm water (50-60°C) is a scolicidal agent, but

Percutaneous Treatment of Hydatid Liver Cysts: An Update

Liver hydatidosis is the most common clinical presentation of cystic echinococcosis. Although liver cystic hydatidosis is considered a benign disease and many patients do not develop symptoms for years, its complications can be severe and life threatening (usually as a consequence of rupture in the biliary tree, in the peritoneum, in the bronchi, and of anaphylactic shock), thus, treatment is recommended for all viable and active hydatid liver cysts. Among the therapeutical options available for this disease, such as open and laparoscopic surgery and chemotherapy, percutaneous treatments have gained considerable interest over the last two decades, due to their efficacy, safety and high patient acceptability. Percutaneous treatments for liver cystic hydatidosis were once discouraged due to the risk of anaphylaxis following cyst puncture. Following the first uneventful attempts in the mid '80's, these treatments were increasingly used and techniques such as PAIR (Puncture, Aspiration, Injection, Re-aspiration) and its variants were developed and implemented in clinical practice. Although the evidence currently available is not sufficient to support or refuse the superiority of PAIR in terms of efficacy, numerous studies have demonstrated that it carries lower rates of morbidity, mortality, and disease recurrence and is associated with shorter hospital stays compared with surgery. The present review provides a brief history of percutaneous treatments for liver cystic hydatidosis, summarizes the currently available evidence on the subject, gives a brief overview of potential future developments in this field focusing on radiofrequency ablation techniques and presents some new patents on the issue.

Hepatic echinococcosis: Clinical and therapeutic aspects

Echinococcosis or hydatid disease (HD) is a zoonosis caused by the larval stages of taeniid cestodes belonging to the genus Echinococcus. Hepatic echinococcosis is a life-threatening disease, mainly differentiated into alveolar and cystic forms, associated with Echinoccus multilocularis (E. multilocularis) and Echinococcus granulosus (E. granulosus) infection, respectively. Cystic echinococcosis (CE) has a worldwide distribution, while hepatic alveolar echinococcosis (AE) is endemic in the Northern hemisphere, including North America and several Asian and European countries, like France, Germany and Austria. E. granulosus young cysts are spherical, unilocular vesicles, consisting of an internal germinal layer and an outer acellular layer. Cyst expansion is associated with a host immune reaction and the subsequent development of a fibrous layer, called the pericyst; old cysts typically present internal septations and daughter cysts. E. multilocularis has a tumor-like, infiltrative behavior, which is responsible for tissue destruction and finally for liver failure. The liver is the main site of HD involvement, for both alveolar and cystic hydatidosis. HD is usually asymptomatic for a long period of time, because cyst growth is commonly slow; the most frequent symptoms are fatigue and abdominal pain. Patients may also present jaundice, hepatomegaly or anaphylaxis, due to cyst leakage or rupture. HD diagnosis is usually accomplished with the combined use of ultrasonography and immunodiagnosis; furthermore, the improvement of surgical techniques, the introduction of minimally invasive treatments [such as puncture, aspiration, injection, re-aspiration (PAIR)] and more effective drugs (such as benzoimidazoles) have deeply changed life expectancy and quality of life of patients with HD. The aim of this article is to provide an up-to-date review of biological, diagnostic, clinical and therapeutic aspects of hepatic echinococcosis.