Diagnosis and treatment of unusual multiorgan Echinococcus hydatid cysts

Abstract

Background

Echinococcosis is a zoonotic disease caused by Echinococcus granulosus. Usually, the liver is the most affected organ, accounting for approximately 70% to 85% of cases. The lungs represent 20% of the cases. Fewer than 10% are found in other sites, including the bone, brain, spleen, and kidneys.

Case presentation

A young man was referred to a local hospital for dull pain in the right flank, fever, and mild cough. Computed tomography showed 2 large cysts: the first involved the left lung and measured 130 × 90.5 × 120 mm, whereas the second cyst was located in the right kidney and measured 130 × 100 × 120 mm. Surgery was performed to remove both lesions in 2 separate surgical sessions.

Conclusions

Echinococcosis is a compulsorily notifiable disease. Collaboration between medical doctors from different specializations is necessary. A multidisciplinary approach is important for the correct therapeutic management of the disease. Furthermore, the high possibility of recurrence makes the long-term follow-up mandatory.

1. Introduction

Echinococcosis is a zoonotic disease caused by Echinococcus granulosus (EG) sensu lato, an etiological agent of cystic echinococcosis (CE).^[1] It has been described in all countries, except Antarctica,^[2] where it represents a huge economic burden and public health problem.^[3] In Italy, CE has a global distribution, with an annual incidence of 1.6/105 inhabitants. However, variations are present in different sporadic, endemic, and hyperendemic areas, with Sardinia and Sicily having the highest average incidence of 6.8/105 and 4.0/105, respectively.^[4] Moreover, based on the Italian Hospital Discharge Records from 2001 to 2014, a cost of more than 53 million Euros and approximately 3000 disability-adjusted life-years were reported, with the highest values linked to Sardinia and Sicily.^[5]

The human infection rate is higher in agropastoral areas, presenting low standards of hygienic conditions, in which dogs and sheep are bred together.^[6,7] Only atypically humans, being dead-end hosts,^[3] acquire the infection. Echinococcus granulosus penetrates blood vessels in the wall of the duodenum and is carried by the bloodstream to the liver, which is the most affected organ.^[8] Echinococcus granulosus that does not colonize the liver is filtered by the lungs.^[9] Less than 10% is found in other sites, including the bone, brain, spleen, and rarely the kidney.^[3] Usually, hydatid cysts gradually develop at a rate of approximately 1 cm per year; thus, it may take 5 to 10 years to reach pathologic size while remaining asymptomatic for several years.^[3,10]

Surgery has always been referred to as the main treatment.^[11] In the case of kidney involvement, nephrectomy should be preferred to marsupialization because of the risk of complications and rupture followed by fatal anaphylaxis.^[12] Medical treatment with albendazole is currently recognized as the drug of choice to treat CE, and presurgical and postsurgical treatment is mandatory to prevent disease relapses.^[13,14]

2. Case presentation

A 31-year-old man from Ghana, a resident of Italy since 2014, was admitted to a local hospital with fever and mild lung symptoms. First, chest radiography was performed, showing an unclear formation at the left upper lobe of the left lung measuring a maximum of 150 mm. An abdominal/thorax computed tomography with contrast was performed, showing 2 large fluid cysts (Fig. 1). The first had an oval shape, located in the upper lobe of the left lung, and measured 130 × 90.5 × 120 mm; it slightly compressed the mediastinal cavity up to the pulmonary artery. The second cyst measured 130 × 100 × 120 mm and was located in the right kidney; it appeared to compress the liver, flattening the VI segment, showing the characteristic feature of hydatidosis. A blood sample was collected from the patient, and the results were positive for the presence of immunoglobulin G antibodies against Echinococcus.^[15]

Figure 1.

Abdominal/thorax computed tomography showing 2 large fluid cysts; upper lobe of the left lung cyst 130 × 90.5 × 120 mm and right kidney cyst 130 × 100× 120 mm.

Before surgery, the patient was treated for 4 days with albendazole at an average dosage of 10 to 15 mg/kg per day, in 2 divided doses, with a fat-rich meal to increase its bioavailability.^[13] This was administered as an adjuvant treatment to surgery, to reduce the size of hydatid cysts, sterilize them, and decrease the number of relapses. After this therapy, lung surgery was performed and consisted of a lobectomy of the left upper lobe. Surgery was followed by 1 month of the same therapy.

Six months after the lung surgery, the patient was admitted to our ward. Meanwhile, the cyst grew to approximately 170 mm, and it showed multiple small cysts bonded to the lateral right wall of the main cyst compressing the kidney and liver, as shown (Fig. 2). No significant symptoms or abnormalities were identified in external physical examinations. According to the literature,^[12] a simple nephrectomy, with no rupture of the cyst, was performed (Fig. 3). The procedure was followed by monitoring at the intensive care unit for 24 hours. The next day, the urinary catheter was removed, and 3 days after the operation, we removed the abdominal drainage. This was followed by a cautious observation period in the ward to monitor hepatic enzymes and possible surgery-related complications. Total genomic deoxyribonucleic acid was extracted from the cystic liquid along with a negative control obtained from a healthy human lymph node. Samples were aliquoted, subjected to DNA extraction using the DNeasy Blood and Tissue Kit (Qiagen, Hilden, Germany), and quantified using a NanoPhotometer® N120 (Implen GmbH, Munich, Germany). Samples were amplified by polymerase chain reaction for EG sensu stricto using primer pairs for the calreticulin gene of 1001 bp, (F5′:CAATTTACGGTAAAGCAT-3′, R5′:CCTCATCTCCACTCTCT-3′). This method can skip the sequencing step and determine the species and genotype of Echinococcus (Supplementary Material, http://links.lww.com/CURRUROL/A16).

Figure 2.

Abnormal growth of the cyst 6 months after the lung surgery. The cyst grew to approximately 170 mm, flattening liver and left kidney's parenchyma.

Figure 3.

Medial aspect of the left kidney. Simple nephrectomy was performed, with no rupture of the cyst.

The patient was discharged after 10 days without any complications. Albendazole therapy was administered as indicated, during the entire period from lung surgery to nephrectomy, with regular monitoring of transaminase levels and complete blood count.

3. Discussion

In this case report, we describe the management, diagnosis, and treatment of a 31-year-old man from Ghana, a resident in Italy since 2014, who was admitted to a local hospital with fever and rare and unusual Echinococcus hydatid cysts located in the left lung and right kidney.

Only larvae that escape filtration by the liver (54%–77%), lungs (9%–30%), and spleen (0.9%–8%) can reach other organs. Thus, kidney CE is a very rare event; according to other reports, it has been detected in approximately 2% to 3% of all sites in other organs.^[16,17] Moreover, metacestodes usually grow slowly and can remain asymptomatic for several years.^[18] In this report, a cyst measuring 170 × 100 × 120 mm located in the right kidney was described. The neoformation reached a large size and began compressing the kidney and liver. Data showed that pathognomonic signs of echinococcosis were not evident during the clinical evaluation of the patient. Consequently, the parasitic neoformation could be underdiagnosed or wrongly considered as a tumor^[19] or an abscess. Evaluation of the specimen led to the definition of the cyst origin: EG sensu stricto G1 genotype. Because this genotype is very common in all Mediterranean basins, we cannot assert whether the patient was infected in Ghana (Africa) or Italy.

Echinococcosis is a compulsorily notifiable disease, and health collaboration between medical doctors from different specializations and veterinary doctors is necessary for the control of the disease in the field.

A multidisciplinary approach with a combination of surgical and therapeutic approaches, as well as collaboration with the Reference Centre for Genetic Analysis, was important for the correct therapeutic management of the disease. Furthermore, the possibility of recurrence makes a long-term follow-up mandatory.

Conflict of interest statement

No conflict of interest has been declared by the authors.