Pathological fracture of femoral neck in a middle-aged woman: a rare presentation of primary hydatid cyst disease in humans

Progress of research on the diagnosis and treatment of bone cystic echinococcosis

Bone cystic echinococcosis (CE) is one of the most complex and dangerous of all echinococcoses. The lack of typical imaging features and clinical manifestations makes diagnosis and treatment of this disease difficult. X-ray and computed tomography (CT) images of bone CE are similar to those of bone cysts, giant-cell bone tumors, and bone metastases, but magnetic resonance imaging (MRI) shows good diagnostic value due to excellent soft-tissue imaging features. Serological tests cannot be used as a definitive diagnostic method for bone CE due to cross-reactivity, which can lead to false-positive or false-negative results. The development of novel antigens can open new frontiers in the diagnosis of the disease. Currently, views conflict on how to diagnose and treat bone CE. Both surgical and pharmacological treatments can be used, but determining which is appropriate is difficult due to the different sites and clinical manifestations of bone CE. Radical resection is not indicated for large-bone injuries, and Pharmacotherapy becomes important. This article reviews the progress of research into the pathogenesis and clinical manifestations of, and diagnostic strategies and treatment options for, bone CE. We aimed to provide a reference for clinical diagnosis and -treatment options.

Evaluation of imaging features of pelvic echinococcosis based on multimodal images

Background

Hydatid disease (HD) is a zoonotic parasitic disease caused by the larvae of Echinococcus, It is mainly prevalent in pastoral areas. Bone echinococcosis is rare, accounting for 0.5 to 4.0% of all echinococcosis. It is likely to miss the diagnosis and misdiagnose due to non-specific early symptoms and the clinical manifestations and imaging features. The clinical data of 15 patients with pelvic cystic echinococcosis were analyzed retrospectively, and the X-ray, CT, and MRI imaging features of the disease were discussed, which are reported below.

Methods

All 15 patients underwent CT scan evaluation. A total of 8 patients underwent coronal, sagittal, and three-dimensional reconstruction with 3-mm-slice thickness, and 4 patients underwent X-ray plain film examination. Five cases underwent MRI scan. Eight cases underwent MRI or CT enhanced scan.

Results

X-ray plain film is characterized by continuous cystic bone destruction, irregular low-density shadow when invading soft tissue, and sometimes calcification which can be seen on the wall or inside the cyst. The involved sacroiliac joint or hip joint may narrow or disappear. The involvement of pelvic cystic echinococcosis is relatively wide, and 80% of patients with pelvic cysts in this group had multiple lesions in the same period. Cystic expansive bone destruction was the most common. Pelvic CT revealed a lobulated hypodense lesion of varying size with internal septae, causing cortical thinning and destruction. Most of them had no periosteal reaction. The iliopsoas muscle is most easily invaded. Single cystic echinococcosis of pelvis showed intermediate or low signal intensity on T1-weighted images and hyperintensity on T2-weighted images in the involved bone and surrounding soft tissue on MRI, and the cyst wall showed linear low signal in T1WI, T2WI, and STIR sequences. The polycystic type is characterized by multiple cysts of varying signal intensity (daughter cysts) within a larger cyst is the typical MRI finding, forming “small vesicles” high signal daughter cysts. Osteosclerosis or calcification showed low signal in T1WI and T2WI.

Conclusions

The results of this study suggest that the lesions of pelvic cystic echinococcosis are mostly cystic expansive and osteolytic bone destruction, which is easy to invade the surrounding soft tissue, often accompanied with calcification; among them, multiple cystic lesions are characteristic.

Pelvic Bone Hydatidosis: A Dangerous Crippling Disease

Hydatid disease is one of the most complicated and devastating conditions caused by Echinococcus granulosus. This globally distributed disease continues to be an important public health concern in many low- and middle-income countries. The liver and the lungs are the most frequently involved sites, but virtually any organ system can be affected. Osseous hydatidosis is relatively less common, but it is extremely debilitating and difficult to manage due to frequent recurrences. Patients often demonstrate a delayed clinical presentation as bone involvement is predominantly a silent and slowly progressive disease with a long latent period. Radiological investigations play an important role in the diagnosis. Although standard therapeutic guidelines are not available, the treatment of choice is a combination of chemotherapy and surgery. Clinicians should perform a lifelong follow-up for early detection of potential recurrence and sequels. This paper aims to highlight hydatid disease of the pelvic bone as an important differential diagnosis of tubercular hip arthritis, especially in areas with high echinococcosis prevalence. 

Presentation Patterns, Diagnostic Modalities, Management Strategies, and Clinical Outcomes in Patients with Hydatid Disease of the Pelvic Bone: A Comparative Review of 31 Cases

Hydatid disease is a parasitic zoonosis commonly caused by Echinococcus granulosus. It characteristically involves the liver and the lungs but rare occurrences in other organs have also been reported. Bone involvement is distinctly uncommon, which is predominantly a silent and slowly progressive disease with a long latent period. We conducted a systematic literature search of MEDLINE, Cochrane, Embase, and Scopus databases. After a comprehensive review of the search results, a total of 31 cases of hydatid disease of the pelvic bone fulfilled the inclusion criteria. The data on patient demographics, epidemiology, lesion site, management, clinical outcomes, and follow-up were collected and analyzed. This review illustrates that hydatid disease should be considered among the differential diagnoses of unusual cystic lesions of the pelvic bone. Prompt diagnosis and appropriate management are of paramount importance to prevent bone destruction and serious complications in these patients. Long-term follow-up should be performed for potential recurrence.