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Case report article, case report: diagnosis of human alveolar echinococcosis via next-generation sequencing analysis.

• 1 Department of Neurology, The Second Medical Center, Chinese PLA General Hospital, Beijing, China
• 2 Department of Neurology, The First Medical Center, Chinese PLA General Hospital, Beijing, China
• 3 Department of Neurology, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing, China

Introduction: Alveolar echinococcosis (AE) is a rare parasitic disease caused by the infection of Echinococcus multilocularis . AE may mimic malignancy both in clinical presentation and radiological imaging, which is often misdiagnosed as metastatic tumor. Recently, next-generation sequencing (NGS) technologies are increasingly being used to address a diverse range of biological questions. Here, we describe a rare case of alveolar echinococcosis diagnosed by pan-pathogen screening, using next-generation sequencing. To the best of our knowledge, this is the first reported case of AE which was definitely diagnosed relying NGS of cerebrospinal fluid (CSF).

Case Presentation: A 33-year-old man presented with repeat seizure and progressive headache for six months. Head magnetic resonance imaging (MRI) showed multiple masses with edema. Lung and abdominal computer tomography (CT) revealed multiple masses in bilateral lung, liver and the right adrenal gland. Bacterial, tuberculosis and fungal infection were excluded by CSF examination. Repeated target biopsy on the masses in the lung and liver showed as fibrous connective tissue without positive findings. NGS of CSF was performed and detected nucleic acid sequences of E. multilocularis . Consequently, the patient has accepted 1-year albendazole therapy. His case was followed up through imaging procedures.

Conclusion: The next-generation sequencing of CSF is a reliable and sensitive diagnostic method for the detection of pathogenic microorganisms, and may allow the accurate diagnosis of alveolar echinococcosis. In view of this case, we recommend NGS as a potential tool for diagnosis of cerebral AE, especially if repeated biopsies are negative.

Introduction

Brain alveolar echinococcosis is a fatal parasitic disease caused by Echinococcus multilocularis ( Deplazes et al., 2017 ), which is often misdiagnosed as metastatic tumor or intracranial tuberculosis. Diagnosis of AE relies on clinical presentation, imaging examinations, serological test and biopsy if available. However, metastatic tumors and AE are difficult to differentiate through imaging examinations. In addition, serological test sometimes results in biologically false-positive results. Herein, we present a rare case of cerebral AE which was finally confirmed by NGS. This is the first reported case which is conclusively diagnosed as cerebral AE by NGS of CSF.

Case Presentation

A 33-year-old man presented repeat seizures and progressive headache for six months. A complete blood count (CBC) showed: hemoglobin 123g/L, white blood cell count 7.73 × 10 9 /L, and percentage of eosinophil 0.009. Liver function showed: alanine transaminase (ALT) 92.8 U/L, aspartate aminotransferase (AST) 44.9U/L, alkaline phosphatase (ALP) 135.1U/L, γ-glutamyl transferase (γ-GT) 313.4 U/L, total bilirubin (TBil) 22.7 mmol/L, direct bilirubin (DBil) 19.4 mmol/L. Head MRI ( Figure 1 ) showed multiple masses with edema. Lung and abdominal CT ( Figure 2 ) presented with several lesions in bilateral lungs, liver and right adrenal gland. Bacterial, tuberculosis and fungal infection were excluded by CSF examination. Serological evaluation of multiple parasite antigen by ELISA were applied. Cysticercosis Immunoglobulin G (IgG) and liver hydatid IgG antibody were both positive. Repeated target biopsy on the masses in the lung and liver showed fibrous connective tissue without positive findings. In addition, we performed positron emission tomography with fluorodeoxyglucose integrated with CT ( 18 F-FDG PET/CT) that showed uptake in all masses with a maximum standardized uptake value of 7.2. Accordingly, it was still hard to draw a definitive pathogenic diagnosis. Therefore, the next-generation sequencing of CSF was performed. The CSF was collected according to standard procedures, and DNA was extracted directly from the sample with TIANamp Micro DNA Kit. The extracted DNA was sonicated to a size of 200–300 bp (Bioruptor Pico protocols). The DNA libraries were constructed and sequencing using the BGISEQ-100 platform. After removing human sequences, the remaining sequencing data were aligned to the microbial databases and detected 161 nucleic acid sequences of E. multilocularis ( Table 1 , E. multilocularis sequences which detected were provided as Supplementary Material ). On this basis, the patient was diagnosed as having AE. Consequently, the patient was recommended a 1-year albendazole therapy. During 1 year of follow-up, symptoms and neurological signs were not aggravated, with decreased seizure frequency. Follow-up CT after 1 year of albendazole treatment revealed slightly decreased multiple lesions and partly relieved surrounding edema in brain. The lesion in the liver (red arrow) was evidently diminished and calcification was slightly increased. The thickened right adrenal gland (yellow arrow) has obviously decreased in size ( Figure 3 ).

Figure 1 . Brain MRI images of the patient. Multiple lesions revealed with isointensity on T1WI (A,B) , hypointensity on T2WI (C,D) surrounded by edema, hypointensity on DWI (E,F) and irregular ring enhancement after injection of Gd-DTPA (G,H) .

Figure 2 . Lung and abdominal CT images of the patient. Multiple Lesions were found in bilateral lung (A,B) and the liver (C) . The right adrenal gland (yellow arrow) was obviously thickened (D) .

Table 1 . List of parasites detected.

Figure 3 . Follow-up CT images of the patient after 1-year albendazole therapy. Brain CT images revealed multiple lesions has slightly shrink and surrounding edema was slightly relieved (A–C) . Abdominal CT images showed that the lesion in liver was obviously diminished accompanied with calcification (D,E) .

Discussion and Conclusions

We reported a special human alveolar echinococcosis case involving the brain, lung, liver, adrenal gland, which was confirmed by NGS. AE is endemic in certain parts of the world, especially in Europe, Northern America, and Central Asia ( Deplazes et al., 2017 ). A recent meta-analysis indicated that the pooled prevalence of AE in China was 0.96% ( Wang et al., 2020 ). In China, the AE endemic area is restricted to the northwest region ( Qian et al., 2017 ), for example, Qinghai province and Gansu province. In most cases, AE is initially located in the liver and spreads into other organs by infiltration or metastasis formation. Extrahepatic lesions are usually located in the lung and brain ( Tappe et al., 2008 ). Adrenal AE, however, is rare, with only 9 cases reported in the literature so far ( Huang and Zheng, 2013 ; Spahn et al., 2016 ; Seidel et al., 2017 ). Our case suggests that AE may involve all parts of the body. We should suspect the diagnosis of AE in a patient with exposure history of parasite and a mass in the adrenal gland.

The diagnosis of AE is complicated by diverse clinical features and mimicking of differential diagnoses. For this case, the patient's biopsy results were negative. Therefore, a biopsy is likely to have lower sensitivity for the diagnosis of AE due to limited tissue specimens. Imaging findings of multiple lesions are helpful in differential diagnosis; however, it can be misinterpreted as other metastatic tumors even by experienced radiologists due to their limited awareness of this condition. Another difficulty in the differential diagnosis of AE and cysticercosis is that serologic test revealed that both of cysticercosis IgG and liver hydatid IgG were all positive. Is it a co-infection or immunological cross-reaction? We prefer immunological cross-reaction since there are common antigens between Cysticercus cellulosae and E. multilocularis . While mixed infection of 2 pathogens is extremely rare. Furthermore, NGS detected nucleic acid sequences of E. multilocularis without sequences of C. cellulose , which conclusively exclude cysticercosis.

Finally, AE diagnosis has been confirmed by NGS for this patient. NGS technologies are increasingly being used to address a diverse range of biological and epidemiological questions since NGS provides pathogen identification without prior target knowledge. In addition, other genetic diagnostic methods, such as PCR, is not applicable for screening of rare and unknown pathogens. We believe that this is the first reported case of AE which was definitely diagnosed relying next-generation sequencing of CSF. Clinicians should promptly recognize that NGS of CSF might be provided as a potential test for detecting cerebral AE.

The limitation of this study includes small sample size. Therefore, if there are similar cases in the future, we should expand the sample size and validate the accuracy of NGS method. In conclusion, the NGS of CSF is a reliable and sensitive diagnostic method to detect pathogenic microorganisms, which may allow accurate diagnoses of cerebral AE.

Data Availability Statement

The original contributions presented in the study are included in the article/ Supplementary Material , further inquiries can be directed to the corresponding author/s.

Ethics Statement

The studies involving human participants were reviewed and approved by This work was supported by National Natural Science Foundation of China (No. 81601086, 81771358). The patients/participants provided their written informed consent to participate in this study. Written informed consent was obtained from the individual(s) for the publication of any potentially identifiable images or data included in this article.

Author Contributions

All co-authors have seen and agree with the contents of the manuscript, that the ICMJE requirements for authorship have been met, and that each author believes that the manuscript represents honest work. All authors contributed to the article and approved the submitted version.

This work was supported by National Natural Science Foundation of China (Grant No.81601086, 81771358).

Conflict of Interest

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Acknowledgments

We would like to thank the patient and his family who are the focus of this report.

Supplementary Material

The Supplementary Material for this article can be found online at: https://www.frontiersin.org/articles/10.3389/fgene.2021.666225/full#supplementary-material

Deplazes, P., Rinaldi, L., Rojas, C., Torgerson, P. R., and Jenkins, E. J. (2017). Global distribution of alveolar and cystic echinococcosis. Adv. Parasitol . 95, 315–493. doi: 10.1016/bs.apar.2016.11.001

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Huang, M., and Zheng, H. (2013). Primary alveolar echinococcosis ( Echinococcus multilocularis ) of the adrenal gland: report of two cases. Int. J. Infect. Dis. 17, e653–e655. doi: 10.1016/j.ijid.2013.03.011

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Qian, M. B., Abela-Ridder, B., Wu, W. P., and Zhou, X. N. (2017). Combating echinococcosis in China: strengthening the research and development. Infect. Dis. Poverty 6:161. doi: 10.1186/s40249-017-0374-3

Seidel, A. K., Pless, M., Michel, C., Soll, C., Hochuli, C., and Gubler, J. (2017). A rare differential diagnosis of an adrenal mass: a case report. Case Rep. Oncol. 10, 981–986. doi: 10.1159/000481501

Spahn, S., Helmchen, B., and Zingg, U. (2016). Alveolar echinococcosis of the right adrenal gland: a case report and review of the literature. J. Med. Case Rep. 10:325. doi: 10.1186/s13256-016-1115-0

Tappe, D., Weise, D., Ziegler, U., Müller, A., Müllges, W., and Stich, A. (2008). Brain and lung metastasis of alveolar echinococcosis in a refugee from a hyperendemic area. J. Med. Microbiol. 57(Pt 11), 1420–1423. doi: 10.1099/jmm.0.2008/002816-0

Wang, X., Dai, G., Li, M., Jia, W., Guo, Z., and Lu, J. (2020). Prevalence of human alveolar echinococcosis in China: a systematic review and meta-analysis. BMC Public Health 20:1105. doi: 10.1186/s12889-020-08989-8

Keywords: alveolar echinococcosis, next-generation sequencing, adrenal gland, Echinococcus multilocularis , diagnose

Citation: Li K, Ma Y, Ban R and Shi Q (2021) Case Report: Diagnosis of Human Alveolar Echinococcosis via Next-Generation Sequencing Analysis. Front. Genet. 12:666225. doi: 10.3389/fgene.2021.666225

Received: 09 February 2021; Accepted: 16 June 2021; Published: 09 July 2021.

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Copyright © 2021 Li, Ma, Ban and Shi. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY) . The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.

*Correspondence: Qiang Shi, shiq301@163.com

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Twenty-six years of involvement with cystic echinococcosis: a case report

• Hosein Safari 1 ,
• Somayeh Mirzavand 2 ,
• Abdollah Rafiei 2 , 3 &
• Molouk Beiromvand   ORCID: orcid.org/0000-0002-8190-8349 2 , 3  

Journal of Medical Case Reports volume  15 , Article number:  266 ( 2021 ) Cite this article

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Introduction

Spinal hydatidosis, a zoonotic disease caused by infection with Echinococcus spp. larvae, is rare, but its treatment remains a significant medical challenge. Approximately 70% of patients with spinal hydatidosis have lesions in their liver, 0–15% have lung involvement, and only 0.5–2% have bone involvement.

Case presentation

Here we report a 38-year-old Iranian man with spinal hydatidosis, who had a history of eight times surgery in over of 26 years due to hydatid cyst in the liver, lungs, and chest wall. At the most recent admission to hospital he presented with chest pain, paraplegia, and urinary incontinence. Magnetic resonance imaging revealed thoracic spinal hydatid disease. He underwent surgery, and the hydatid cysts were completely removed. Lower extremity forces recovered dramatically and completely within 4 weeks.

Spinal hydatidosis is a rare disease, but it is associated with a high degree of morbidity, mortality, and poor prognosis. Because of the infiltrative nature of hydatid disease, surgery alone is rarely curative. The current case study demonstrates the importance of a suitable surgical approach, adequate intraoperative prophylaxis to prevent cyst rupture, and prolonged complete paraplegia.

Peer Review reports

Human cystic echinococcosis (CE), caused by the larval form of Echinococcus granulosus sensu stricto is a parasitic zoonotic disease which mainly occurs in pastoral areas worldwide [ 1 , 2 , 3 ]. Lesions are localized to the liver in approximately 70% of patients with CE and to the lungs in approximately 20%; other cases show the involvement of other organs [ 1 ]. Bone involvement is seen in 0.5−2% of hydatid cases, with most of these cases involving hydatid cysts in the spine.

A 38-year-old Iranian man, residing in a rural area, was admitted to our surgery unit with a history of back pain, chest pain, paraplegia and urinary incontinence within the last 45 days. The patient had a history of hydatid cyst(s) in the liver, lungs, and chest wall. The first surgery occurred 26 years previously when he was 12 years old and underwent thoracotomy for two hydatid cysts in the left lung. Subsequently, in April 1999, the patient was diagnosed with a hydatid cyst in his left lung and underwent surgery again. Nine years later, after confirmation of a hydatid cyst in his left lung, he underwent thoracotomy. In May 2011, computerized tomography (CT) revealed multiple cysts located behind the left lung and the fourth rib (R4), leading to the diagnosis of paraspinal hydatidosis and a second thoracotomy. In May 2014, his imaging results demonstrated the presence of four hydatid cysts in the left hemithorax. Total cystectomy was performed for one cyst under the latissimus dorsi, and two cysts behind the third rib (R3) and one cyst behind his left clavicle were drained. In the same year, one hydatid cyst was detected in his liver, and hepatic resection was performed. In March 2018, imaging results demonstrated the presence of multiple cystic lesions under R3, R3 and the fifth rib (R5). Thoracotomy was once again performed, and the cystic lesions and the necks of R3, R4, and R5 were removed. After surgery, albendazole therapy (400 mg/kg) was initiated and continued.

In December 2019 the patient was referred to our surgery unit with progressive weakness. Spinal magnetic resonance imaging (MRI) showed multiple spinal epidural cystic lesions at the level of the third to fourth thoracic vertebrae (T3–T4) (Figs. 1 , 2 ) and that the pedicles on both sides of T4, some parts of the lamina, and the vertebral body were destroyed. The patient underwent surgical resection with the costotransverse approach, and multiple epidural cystic lesions at the T3–T4 level were completely removed. Multiple extradural cystic lesions were carefully excised to avoid intraoperative rupture of the cysts. Intraoperatively, irrigation with hypertonic saline (as scolicidal agents) and cotton pads soaked with hypertonic saline were used. Since the T3 and T4 pedicles had been destroyed, posterior fusion with pedicular screw was performed. The diagnosis of hydatid cyst was confirmed by pathological examination, following which treatment with 400 mg/kg albendazole was started, with the recommendation that the treatment continue for 6 months. Within 2 weeks after surgery, his lower extremity forces dramatically returned and he was full force after 4 weeks.

a Sagittal magnetic resonance imaging image at the level of the second thoracic vertebra of the patient, showing a lesion consisting of multiple cysts (white arrow) in the thoracic spinal cord. b Two-dimensional myelogram image showing a multiple cystic lesion (white arrow)

a Intraoperative photos of the patient. b Multiple grape-like daughter cysts, which were completely removed by surgical resection with the costotransverse approach

Discussion and conclusions

Spinal hydatidosis is a rare form of hydatidosis and affects fewer than 1% of all patients with hydatidosis. Approximately one half of all patients with hydatidosis of bone have spinal hydatidosis; the other 50% have hydatidosis in the thoracic region. Previous studies have demonstrated that approximately 85% and 25–77% of patients suffered from back pain and paraplegia, respectively [ 4 ]. In our case, the lesion was extradural and located in the thoracic region (T3–T4), with paraspinal extension, and the patient had a history of back pain, chest pain, urinary incontinence, and paraplegia.

Surgical treatment with removal of the whole cyst(s) is the gold standard treatment in spinal hydatidosis [ 5 ]. Several factors, such as location of the cyst, familiarity with the surgical approach, and surgeon preference, are involved in the choice of surgical procedures [ 6 ]. Moreover, choosing the suitable surgical technique depends on an accurate diagnosis of the hydatid cysts in order to prevent intraoperative cyst spillage. Surgery in thoracic cases is mainly posterior [ 4 ]. During the surgery, most surgeons use scolicidal agents, such as hypertonic saline, 0.5% silver nitrate, chlorhexidine, and/or 80% ethanol to prevent rupture of hydatid cysts. Among these, 3% hypertonic saline is the most frequently used scolicidal agent [ 4 ].

Primary hydatid cysts usually contain daughter cysts, and the rupture of these daughter cysts can lead to secondary cysts [ 7 ]. The risk of release of the daughter cysts increases with bone involvement. Although it was not easy to distinguish primary or secondary cysts in the present case, the patient’s history suggests the possibility of secondary cysts. Despite a history of 1-month complete paraplegia, a dramatic neurologic recovery was observed, and thepatient fully recovered within 4 weeks. This finding suggests the slow growth nature of the lesion.

Because of the invasive nature of hydatid disease, surgery alone is rarely curative. Therefore, a correct preoperative diagnosis, choosing the suitable surgical technique, considering the infiltrative nature of the cyst, intraoperative prophylaxis to reduce spillage, and posterior surgical approach for treatment are of crucial importance in preventing recurrence.

Availability of data and materials

All data generated or analyzed during this study are included in the article.

Abbreviations

• Cystic echinococcosis

Computerized tomography

Magnetic resonance imaging

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Department of Neurosurgery, Golestan Hospital–Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Khuzestan, Iran

Hosein Safari

Department of Parasitology, School of Medicine, Ahvaz Jundishapur University of Medical Sciences, P.O. Box 61357–15794, Ahvaz, Khuzestan, Iran

Somayeh Mirzavand, Abdollah Rafiei & Molouk Beiromvand

Infectious and Tropical Diseases Research Center, Health Research Institute, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Khuzestan, Iran

Abdollah Rafiei & Molouk Beiromvand

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HS is the patient’s chief surgeon and he operated on the patient. MB, HS, AR, and SM wrote the manuscript. All authors read and approved the final manuscript.

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Correspondence to Molouk Beiromvand .

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Safari, H., Mirzavand, S., Rafiei, A. et al. Twenty-six years of involvement with cystic echinococcosis: a case report. J Med Case Reports 15 , 266 (2021). https://doi.org/10.1186/s13256-021-02810-9

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Received : 29 December 2020

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Published : 12 May 2021

DOI : https://doi.org/10.1186/s13256-021-02810-9

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Pulmonary cystic echinococcosis: A case report from tertiary care hospital

Sheetal bankar.

Department of Microbiology, Orchid Medical Centre, Ranchi, Jharkhand, India

Phudang Rebon Tokbipi

1 Department of Microbiology, GNRC, Dispur, Guwahati, India

Isha Ranwadkar

2 Department of Microbiology, Topiwala National Medical College, Mumbai, Maharashtra, India

Jayanthi Shastri

3 Department of Microbiology, Topiwala National Medical College and B.Y.L. Nair Ch. Hospital, Mumbai, Maharashtra, India

Human echinococcosis is a zoonotic infection transmitted by dogs in livestock-raising areas. We present a case of a 30-year-old female with respiratory symptoms.

INTRODUCTION

Human echinococcosis is caused by larval forms (metacestodes) of the tapeworm of the genus Echinococcus . Human infection is acquired from ingestion of the parasite eggs from infected animals. Echinococcus granulosus causes cystic echinococcosis in humans. This relatively benign parasitic disease is characterized by slowly growing cysts most commonly in the liver (accounting for 50%–70% of cases), followed by the lungs (20%–30%), and less frequently the spleen, kidneys, heart, bones, central nervous system, and other organs.[ 1 ] In India, the highest prevalence is reported in Andhra Pradesh and Tamil Nadu than in other parts of the country.[ 2 ] Since there is a scarcity of reports on pulmonary echinococcosis from the Western part of the country, this case report is presented.

CASE REPORT

A 30-year-old female presented with cough and mucous expectoration, mild fever, and dyspnea on exertion for 2 months in June 2015. On clinical examination, chest movements and breath sounds were decreased on the right side. Chest X-ray revealed homogenous opacity in the right mid and lower zone. Computed tomography (CT) scan of the chest showed a thick-walled, unilocular, fluid-filled cystic lesion in the superior part of the right lower lobe of dimension 5.8 cm × 6.5 cm × 7.1 cm with heterogeneous contents, compressing the right lower lobe bronchus. IgG antibodies for Echinococcus granulosus were positive. Bronchoscopy showed a sign of white glistening membrane-like structures in the superior segment of the right lower lobe which was aspirated and sent to microbiology laboratory. The specimen was processed in the parasitology division of the department of microbiology. A wet mount of the aspirated fluid showed brood capsules of E. granulosus with scolices [ Figure 1 ]. The cyst was removed surgically, and the patient was started on albendazole (ABZ) 400 mg daily for 6 months.

Brood capsule of Echinococcus granulosus

Majority of the Echinococcus cysts are seen in the liver. Those bypassing the liver are likely to travel through the right side of the heart or lymphatic vessels or bronchi to the lungs.[ 3 ]

Clinical presentation of pulmonary hydatid cysts depends on the size of the cyst and whether the cyst is intact or ruptured. The cysts grow at the rate of 1–1.5 cm/year.[ 4 ] It may be symptomless for 10–20 years until they become large enough to produce symptoms.[ 5 ] In this case, the patient might have acquired the infection in her childhood as she was born in a farmer's family and was in contact with the animals at her native place. As the cysts are slow growing, symptoms developed in adulthood.

A complicated cyst ruptures into a bronchus, pleural cavity, or biliary tree and presents with expectoration of cystic contents, productive cough, repetitive hemoptysis, fever, or anaphylactic shock.[ 6 ] Most of the times, only one lobe is involved in 72% of cases, usually at the base of the lung.[ 7 ] In this case, the right lower lobe was affected. The primary diagnosis is obtained by X-ray, ultrasonography, and CT scan. Apart from routine tests, serological tests available are ELISA as a screening test and immunoelectrophoresis (IE) as a confirmatory test. An antibody titer >1:160 is usually considered positive. Diagnosis is established if both ELISA and IE are positive. Serology may be negative in 10%–15% of cases, especially in well-encapsulated cysts. The sensitivity of serological tests for liver cysts is 80%–90% and specificity is 88%–96%. For pulmonary cysts, sensitivity is only 50%–60%. IgG4 response is more pronounced than that of IgG1.[ 8 ]

The mainstay of the treatment is surgery. In our case, a complete excision of the cyst was performed. According to the WHO guidelines, benzimidazole is the preferred treatment when surgery is not available. Medical treatment includes long courses of ABZ given 400 mg twice a day.[ 9 ]

In order to minimize the transmission of disease, it is important to educate population in endemic areas about careful washing of hands and foods. The feeding of livestock entrails to dogs is a common starting point for the tapeworm life cycle and should be avoided.[ 10 ]

Farmers commonly come in contact with animals and might acquire a zoonotic disease. Environmental contamination of soil by dogs' feces might be an important route of transmission in rural community. This case report signifies that pulmonary echinococcosis needs consideration in the differential diagnosis, especially when a patient presents with respiratory symptoms. Such diseases can be prevented by simple hygienic practices such as handwashing and proper washing of food. Educational programs should be initiated early because, presumably, most infections are acquired in childhood.

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Case #366 – February 2014

A 28-year-old male from Algeria had complaints of right upper quadrant (RUQ) abdominal pain. As part of his work up at a medical facility, imaging studies revealed a complex solid and cystic lesion in the posterior right hepatic dome. Hepatic cyst fluid was aspirated and submitted for ova-and-parasite (O&P) testing. Figures A – D show what was observed on a wet-mount made from the sediment of the fluid. Figures A and C were captured at 100x magnifications; Figures B and D at 200x magnification. What is your diagnosis? Based on what criteria?

This was a case of echinococcosis caused by Echinococcus granulosus . The images showed individual protoscoleces with characteristic suckers and refractile hooks. The presence of a single cyst was also compatible with E. granulosus . Serologic tests can be very helpful in the diagnosis or confirmation of echinococcosis, and may be used before invasive methods.

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