Image-guided percutaneous biopsy and pathological diagnosis in atypical tuberculous spondylitis: a case series and clinical outcomes

Abstract

Background: Tuberculous spondylitis can be difficult to distinguish from alternative spinal pathologies such as malignancy, particularly if the imaging features are not typical. Biopsy and histopathological analysis are facilitative to the early and accurate diagnosis of atypical tuberculous spondylitis and the clinical management. The purpose of this study is to describe some of the atypical imaging features of tuberculous spondylitis diagnosed by image-guided percutaneous biopsy, as well as associated treatment outcomes.

Methods: We performed a retrospective analysis of all patients diagnosed with tuberculous spondylitis after image-guided percutaneous biopsy at The Third Affiliated Hospital of Southern Medical University between 2013 and 2020. Of the patients identified, those with atypical imaging features were selected for case review. All patients were given anti-tuberculous medication treatment with or without surgery. The imaging features, histological and microbiological results, and clinical presentations and outcomes were evaluated. Neurological function was evaluated according to the Frankel grading system. The clinical outcomes were evaluated by Visual Analogic Scale (VAS) scores for pain, imaging [X-ray, computed tomography (CT), and magnetic resonance imaging (MRI)] results, and laboratory examinations. Comparison of VAS scores was made by Student t-test.

Results: Of the 102 patients identified with tuberculous spondylitis between 2013 and 2020, eight patients (two females and six males) with a mean age of 41.6 years (range, 18-61 years) demonstrated atypical imaging findings, including central vertebral body lesion, multiple skip vertebral lesions, extradural mass lesion and anterior subperiosteal lesion. All eight patients received anti-tuberculous medication treatment, and six underwent surgery. One patient developed a pleural effusion after debridement of the thoracic lesion. The mean follow-up period was 16.2 months (6-37 months). The VAS scores before treatment and at the final follow-up showed significant differences (7.25±1.49 and 0.0±0.0, respectively, P<0.01). Improved neurological function were observed in all patients. Solid fusion and osteogenic osteosclerosis were observed at the final follow-up, and no recurrence was observed in any cases.

Conclusions: All eight patients had a good prognosis. Image-guided biopsy and histopathological analysis are helpful for the early diagnosis of tuberculous spondylitis, especially when imaging features are not typical for this condition.

Keywords: Tuberculosis (TB); atypical tuberculous spondylitis; case series; image-guided percutaneous biopsy; tuberculous spondylitis.

Figure 1

A 41-year-old woman with atypical spinal TB at L3. (A) Sagittal MR image showing lobulated pre- and paravertebral lesion at the L3 level. (B) Enhanced MRI scan revealing rim enhancement of the L3 vertebral and paravertebral lesions. (C) Sagittal CT images show bony destruction involving the L3 vertebra. (D) Axial MR image shows the involvement of the L3 vertebral body and the posterior elements associated with posterior epidural extension, forming an epidural lesion and causing a slight degree of dural compression. (E) Axial CT image showing osteolytic destruction of the L3 vertebral body. (F,G) Biopsy is performed using a transpedicular approach of the L3 vertebral body lesion. (H) The histopathologic analysis reveals fibro-collagenous tissue with numerous epithelioid granulomata mixed with multinucleated giant cells (HE staining, ×100). (I) Ziehl-Neelsen staining (×400) demonstrates AFB (arrows). (J,K) Postoperative anteroposterior and lateral X-ray images. (L,M) Axial and sagittal CT images show good fusion of the bone grafts inside the L3 vertebral body one year after surgery. TB, tuberculosis; MR, magnetic resonance; AFB, acid-fast bacilli; CT, computed tomography; HE, hematoxylin and eosin.

Figure 2

A 58-year-old woman with multiple osteolytic lesions. (A,B) X-rays of the right humerus, right radius, and left fibula demonstrated lytic bone lesions (arrows). (C,D) CT imaging of the chest and thoracic spine showed bilateral pleural effusion, osteolysis, and secondary pathologic fracture of the T8 vertebra. (E) Using a posterolateral approach biopsy is performed of the right humerus lesion. (F) The histopathologic analysis revealed damaged bone tissue with numerous neutrophils without granulomata. Ziehl-Neelsen staining (×400) shows AFB (arrows). CT, computed tomography; AFB, acid-fast bacilli.

Figure 3

An 18-year-old man with atypical spinal TB in the lumbar spine. (A,C) Axial and sagittal MR images show lytic lesions in the first and fifth lumbar vertebral bodies and the third lumbar vertebral pedicle without disc involvement. (B,D) Axial and sagittal CT images show collapse of the L1 vertebral body in addition to dural sac compression. (E) The histopathology shows fibro-collagenous tissue with numerous epithelioid cells mixed with multinucleated giant cells. Extensive areas of caseous necrosis are seen (HE staining, ×100). (F) Ziehl-Neelsen staining (×400) shows AFB (arrows). (G,H) Postoperative axial and sagittal CT images. (I,J) Axial and sagittal CT images one year postoperatively show good fusion of the bone grafts inside the L1 vertebral body. TB, tuberculosis; CT, computed tomography; HE, hematoxylin and eosin; AFB, acid-fast bacilli.