Severe kyphoscoliosis after primary Echinococcus granulosus infection of the spine

Abstract

A primary Echinococcus granulosus infection of the spine involving the vertebrae T8 and T9 of a 6-year-old child was treated elsewhere by thoracotomy, partial corporectomy, multiple laminectomies and uninstrumented fusion. Owing to inappropriate stabilization, severe deformity developed secondary to these surgeries. X-rays, CT and MRI scans of the spine revealed a severe thoracic kyphoscoliosis of more than 100 degrees (Fig. 1) and recurrence of Echinococcus granulosus infection. The intraspinal cyst formation was located between the stretched dural sac and the vertebral bodies of the kyphotic apex causing significant compression of the cord (Figs. 2, 3, 4). A progressive neurologic deficit was reported by the patient. At the time of referral, the patient was wheelchair bound and unable to walk by herself (Frankel Grade C). Standard antiinfectious therapy of Echinococcus granulosus requires a minimum treatment period of 3 months. This should be done before any surgical intervention because in case of a rupture of an active cyst, the delivered lipoprotein antigens of the parasite may cause a potentially lethal anaphylactic shock. Owing to the critical neurological status, we decided to perform surgery without full length preoperative antiinfectious therapy. Surgical treatment consisted in posterior vertebral column resection technique with an extensive bilateral costotransversectomy over three levels, re-decompression with cyst excision around the apex and multilevel corporectomy of the apex of the deformity. Stabilisation and correction of the spinal deformity were done by insertion of a vertebral body replacement cage anteriorly and posterior shortening by compression and by a multisegmental pedicle screw construct. After the surgery, antihelminthic therapy was continued. The patients neurological deficits resolved quickly: 4 weeks after surgery, the patient had Frankel Grade D and was ambulatory without any assistance. After an 18-month follow-up, the patient is free of recurrence of infection and free of neurologically deficits (Frankel E). This case demonstrates that inappropriate treatment--partial resection of the cyst, inappropriate anterior stabilization and posterior multilevel laminectomies without posterior stabilization--may lead to severe progressive kyphoscoliotic deformity and recurrence of infection, both leading to significant neurological injury presenting as a very difficult to treat pathology. Fig. 1 X-rays of the patient showing a kyhoscoliotic deformity. a ap view, b lateral view Fig. 2 CT reconstruction of the whole spine showing the apex of the deformity is located in the area of the previous surgeries Fig. 3 Sagittal CT-cut showing the bone bloc at the apex with a translation deformity Fig. 4 Sagittal T2-weighted MRI image showing the cystic formation at the apex.

Fig. 1

X-rays of the patient showing a kyhoscoliotic deformity. a ap view, b lateral view

Fig. 2

CT reconstruction of the whole spine showing the apex of the deformity is located in the area of the previous surgeries

Fig. 3

Sagittal CT-cut showing the bone bloc at the apex with a translation deformity

Fig. 4

Sagittal T2-weighted MRI image showing the cystic formation at the apex

Fig. 5

Axial T2-weighted MRI image showing the intraspinal cyst formation with spinal cord compression

Fig. 6

Preoperative image showing the kyphotic deformity (gibbus)

Fig. 7

Intraoperative image showing the kyphotic apex (gibbus) of the iatrogenic deformity. Pedicle screws have been placed and the ribs were exposed to perform the costotransversectomy

Fig. 8

Intraoperative image after left side costotransversectomy. The lung and the big vessels are retracted, the cord has been exposed and is stretched over the apex of the deformity. Anteriorly, the apex has already been removed with a high-speed burr

Fig. 9

Intraoperative image showing a vertebral body replacement device placed into the anterior defect to serve as a hypomochlion. The posterior wall has been removed and the cord is completely decompressed

Fig. 10

Postoperative image showing the patient’s back after the correction

Fig. 11

Postoperative 3D CT reconstruction of the whole spine at 18 months follow-up showing lateral views of the corrected spine

Fig. 12

Postoperative X-rays at 18 months follow-up. a ap view, b lateral view