Atypical mycobacterial spondylitis as a challenging differential diagnosis to metastatic disease of the spine: a case report

Diagnosis and Treatment of Skipped Multifocal Spinal Tuberculosis Lesions

Spinal tuberculosis, also known as Pott's disease or tuberculous spondylitis, is usually secondary to primary infection in the lungs or other systems, and in most instances, is thought to be transmitted via blood. Typical manifestations of infection include narrowing of the intervertebral disc by erosion and bone destruction of adjacent vertebrae. Atypical spinal tuberculosis is a specific type of spinal tuberculosis. It mainly consists of single vertebral lesions, single posterior structure lesions, multiple vertebral lesions, and intra-spinal lesions. Skipped multifocal spinal tuberculosis is one of these types and is characterized by two or more vertebral lesions without the involvement of the adjoining intervertebral discs, regardless of their location. To date, only a few cases have been reported. Upon clinical admission, it can be treated conservatively or surgically, depending on the patient's symptoms. In addition, gene or biological therapies are being investigated. However, because of the exceptional imaging findings and insidious symptoms, it is often misdiagnosed as a neoplastic lesion, osteoporotic fracture, or other infectious spondylitis, increasing the risk of neurological deficit and kyphotic deformity, and delaying the optimal treatment window. In this study, we review the diagnosis and treatment strategies for skipped multifocal spinal tuberculosis lesions and enumerate the common differential diagnoses, to provide reference and guidance for clinical treatment and diagnosis direction.

A Scoring System for Outpatient Orthopedist to Preliminarily Distinguish Spinal Metastasis from Spinal Tuberculosis: A Retrospective Analysis of 141 Patients

Objective

Spinal tuberculosis (TB) misdiagnosed of spinal metastasis was not rarely reported, especially in outpatients department. This study was aimed to establish an outpatient scoring system to preliminarily distinguish spinal metastasis from spinal TB.

Methods

We retrospectively reviewed consecutive 141 patients with a pathological diagnosis of spinal metastasis (82 cases) or spinal TB (59 cases) in our hospital from January 2017 to June 2018. The following clinical characteristics which can be obtained by outpatient orthopedist were recorded and analyzed: age, gender, malignant tumor history, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and imaging features including distribution characteristics of vertebral lesions, subligamentous spread, paravertebral or psoas abscess, involved vertebral element, intervertebral disc, and sequestra formation. The prevalence of clinical characteristics in spinal metastasis was evaluated, and the scoring system was established using logistic regression analysis. The performance of the scoring system was also prospectively validated.

Results

The outpatient scoring system was based on five clinical characteristics confirmed as significant predictors of spinal metastasis, namely, malignant tumor history, subligamentous spread, posterior element lesions, preserved discs, and no sequestra formation. Spinal metastasis showed a significant higher score than spinal TB (8.17 points vs. 1.97 points, t = 18.621, P < 0.001), and the optimal cut-off value for the scoring system was 5 points. The sensitivity and specificity of the scoring system for predicting spinal metastasis were 97.85% and 88.33%, respectively, in the validation set.

Conclusion

Spinal lesions with the score of 5 to 10 would be considered a diagnosis of spinal metastasis, while the score of 0 to 4 may be spinal TB. Because the scoring system is mainly based on the clinical characteristics that can be obtained by an outpatient orthopedist, it is suitable to be used as a diagnostic tool in the outpatient department.

Multi-stage surgery for a multiple-level spondylodiscitis caused by multidrug-resistant Mycobacterium avium complex

The objective of this article is to report a rare case of atypical mycobacterial spinal spondylodiscitis with multiple-level involvement and the successful treatment by multi-stage surgical intervention. Reports on the surgical management of atypical mycobacterial spondylodiscitis are lacking. A 71-year-old woman with a confirmed diagnosis of multiple-level spondylodiscitis of L2-L3 and L5-S1 caused by Mycobacterium avium complex (MAC). The patient underwent a two-stage surgical treatment (first: posterior instrumentation; second: anterior debridement with anterior lumbar interbody fusion). At 1 year after surgery, the patient suffered a proximal junctional failure secondary to a vertebral fracture that was solved with a proximal extension of the fusion using a percutaneous technique. The patient was successfully discharged with good pain control, satisfactory correction, no neurologic complications and an overall satisfactory outcome. A rare case of antibiotic-resistant multi-level spondylodiscitis due to MAC was treated successfully with multi-stage surgical treatment. Surgery in this patient group remains challenging due to the technical complexities and the difficulty of choosing the instrumentation levels.

Vertebral osteomyelitis caused by non-tuberculous mycobacteria: Predisposing conditions and clinical characteristics of six cases and a review of 63 cases in the literature

Background Several case series have reported on clinical and radiographic characteristics of patients with vertebral osteomyelitis (VO) caused by non-tuberculous mycobacteria (NTM). However, only a few patients were included, and systematic reviews are still lacking. The aim of this study was to update and summarise the pre-disposing conditions, clinical and radiographic characteristics of such cases due to NTM. Methods In this study, a systematic review was conducted of the English-language literature from 1961-2014 to investigate the pre-disposing conditions and characteristics of cases of VO due to NTM. Also, six additional cases diagnosed in the study hospitals were described; these cases are included in an analysis of a total of 69 cases of NTM VO. Results The most common species, regardless of the presence of HIV co-infection, was M. avium Complex followed by M. xenopi. Ten cases with HIV infection had a median CD4 lymphocyte count of 320/mm(3) (range = 41-465/mm(3)) at the time of diagnosis of NTM VO. The VO in the cases with HIV infections occurred at an earlier age and more often involved the thoracic spine than in the cases without HIV infection. Pre-disposing trauma or surgery was reported in 14.5% (10/69) of the cases. A variety of immunosuppressive diseases were observed in 49.3% of the patients, including the 10 with HIV infections and corticosteroids were used in 27.5% of the cases. Surgery was performed in 67.6% and improvement was reported in 80.6%. Conclusion NTM should be considered in immunocompromised patients with indolent VO without confirmation of tuberculosis.