Surgeon variation: a south african spinal pathology treatment survey.

PURPOSE: To investigate variation in treatment decisions among spine surgeons in South Africa and the association between surgeon characteristics and the treatment they select. METHODS: We surveyed 79 South African spine surgeons. We presented four vignettes (cervical spine distractive flexion injury, lumbar disc herniation, degenerative spondylolisthesis with stenosis, and insufficiency fracture) for them to assess and select treatments. We calculated the index of qualitative variation (IQV) to determine the degree of variability within each vignette. We used Fisher's exact, and Kruskal-Wallis tests to assess the relationships between surgeons' characteristics and their responses per vignette. We compared their responses to the recommendations of a panel of spine specialists. RESULTS: IQVs showed moderate to high variability for cervical spine distractive flexion injury and insufficiency fracture and slightly lower levels of variability for lumbar disc herniation and degenerative spondylolisthesis with stenosis. This confirms the heterogeneity in South African spine surgeons' management of spinal pathologies. The surgeon characteristics associated with their treatment selection that were important were caseload, experience and training, and external funding. Also, 19% of the surgeons selected a treatment option that the Panel did not support. CONCLUSION: The findings make a case for evaluating patient outcomes and costs to identify value-based care. Such research would help countries that are seeking to contract with providers on value. Greater uniformity in treatment and easily accessible outcomes reporting would provide guidance for patients. Further investment in training and participation in fellowship programs may be necessary, along with greater dissemination of information from the literature.

Culture filtrate supplementation can be used to improve Mycobacterium tuberculosis culture positivity for spinal tuberculosis diagnosis.

Culture remains the gold standard to diagnose spinal tuberculosis (STB) despite the paucibacillary nature of the disease. Current methods can take up to 42 days to yield a result, delaying the ability to rapidly detect drug resistance. Studies have demonstrated the use of supplementation with culture filtrate (CF) from an axenic culture of Mycobacterium tuberculosis (Mtb) as a source of growth factors to improve culture rates. Our objective was to test a modified culture assay, utilizing CF supplemented media (CFSM), to improve culture positivity rates for suspected STB. Twelve patients with suspected STB were assessed by conventional culture (BACTEC™ MGIT 960), GeneXpert™ and standard histopathological examination. Spinal biopsies were taken from areas of diseased vertebral tissue or abscess, predetermined from MRI. Additional biopsies were obtained to assess CFSM for improved detection and faster culture of Mtb. All cases were diagnosed as STB and treated empirically for tuberculosis based on either bacteriological evidence (GeneXpert™, MGIT and/or CFSM positive), or based on clinical presentation. 5 specimens (45.45%) were positive for Mtb DNA as detected by GeneXpert™ and 1 specimen (8.33%) was cultured using MGIT (time to detection; 18 days). CFSM was able to culture 7 specimens (58.3%), with all CFSM positive specimens yielding a culture within 14 days. Two samples were positive only using the CFSM assay pointing to additional yield for diagnostic workup. Modification of standard culture can improve detection of Mtb and reduce time to positivity in individuals with STB where culture material is a requirement.

Evaluation of host biomarkers for monitoring treatment response in spinal tuberculosis: A 12-month cohort study.

BACKGROUND: Monitoring treatment response is an important precaution in spinal tuberculosis (TB), particularly when the condition was clinically diagnosed rather than bacteriologically confirmed and when drug susceptibility testing was not performed. Conventional monitoring measures have limitations and there is a need for favourable alternatives. Therefore, this study aimed to investigate changes in immune biomarkers over the course of treatment for spinal TB and to compare these responses to the conventional monitoring measure, erythrocyte sedimentation rate (ESR). METHODS: Patients with spinal TB were recruited from a tertiary hospital in the Western Cape, South Africa, and provided blood samples at 0, 3, 6, 9 and 12 months of TB treatment. Blood samples were analysed for ESR, using standard techniques, and for 19 cytokines, using a multiplex platform. Changes in ESR and cytokine levels were investigated using a mixed model ANOVA and Least Significant Difference post-hoc testing. RESULTS: Twenty-six patients with spinal TB were included in the study although only fifteen remained in follow-up at 12 months. Seven biomarkers changed significantly over the course of treatment (CRP, Fibrinogen, IFN-γ, Ferritin, VEGF-A, ApoA1 and NCAM, p < 0.01) with a further three showing a strong trend towards change (CCL1, CXCL9 and GDF-15, 0.05 ≥ p ≤ 0.06). Responsive biomarkers could be approximately grouped according to patterns of progressive, initial or delayed change. ESR performed similarly to CRP, Fibrinogen and IFN-γ with all showing significant decreases between 0, 6 and 12- months of treatment. Individual ESR responses were variable. DISCUSSION: Individual ESR responses may be unreliable and support the investigation of multi-marker approaches to evaluating treatment response in spinal TB. Biomarkers of treatment response identified in the current study require validation in a larger study, which may also incorporate aspects such as evaluating biomarkers within the first week of treatment and the inclusion of a healthy control group.

Candidate Biomarkers to Distinguish Spinal Tuberculosis From Mechanical Back Pain in a Tuberculosis Endemic Setting.

Background: Spinal tuberculosis (TB) may have a variable, non-specific presentation including back pain with- or without- constitutional symptoms. Further tools are needed to aid early diagnosis of this potentially severe form of TB and immunological biomarkers may show potential in this regard. The aim of this study was to investigate the utility of host serum biomarkers to distinguish spinal TB from mechanical back pain. Methods: Patients with suspected spinal TB or suspected mechanical back pain were recruited from a tertiary hospital in the Western Cape, South Africa, and provided a blood sample for biomarker analysis. Diagnosis was subsequently confirmed using bacteriological testing, advanced imaging and/or clinical evaluation, as appropriate. The concentrations of 19 host biomarkers were evaluated in serum samples using the Luminex platform. Receiver Operating Characteristic (ROC) curves and General Discriminant Analysis were used to identify biomarkers with the potential to distinguish spinal TB from mechanical back pain. Results: Twenty-six patients with spinal TB and 17 with mechanical back pain were recruited. Seven out of 19 biomarkers were significantly different between groups, of which Fibrinogen, CRP, IFN-γ and NCAM were the individual markers with the highest discrimination utility (Area Under Curve ROC plot 0.88-0.99). A five-marker biosignature (CRP, NCAM, Ferritin, CXCL8 and GDF-15) correctly classified all study participants after leave-one-out cross-validation. Conclusion: This study identified host serum biomarkers with the potential to diagnose spinal TB, including a five-marker biosignature. These preliminary findings require validation in larger studies.

Biomarkers to predict FDG PET/CT activity after the standard duration of treatment for spinal tuberculosis: An exploratory study.

OBJECTIVES: 18F-Fluorodeoxyglucose (FDG) Positron Emission Tomography- Computed Tomography (PET/CT) scans can be used to assess healing following treatment for spinal tuberculosis (TB) but have limited accessibility and high cost. This study investigated the association between immune biomarkers and FDG-PET/CT activity after ≥9 months of treatment for spinal TB. METHODS: Patients who had completed ≥9 months of treatment for spinal TB were recruited from a major hospital in the Western Cape, South Africa. Participants underwent a FDG-PET/CT scan and FDG- PET/CT activity was quantified for all spinal and extra-spinal sites. Participants also provided a blood sample, which was evaluated for 19 cytokines along with erythrocyte sedimentation rate (ESR). Correlations and multiple regression analyses were used to investigate the association between biomarkers and PET/CT measures. RESULTS: Twenty-eight patients were recruited, of whom 24 (86%) had spinal and/or extra-spinal FDG-PET/CT activity. In the strongest multiple regression model, CXCL10/IP-10, VEGFA, IFN-γ, CRP and Factor D/Adipsin explained 52% of the variation in overall maximal FDG uptake. Conventional monitoring marker ESR showed no significant association with PET/CT measures. CONCLUSIONS: The current findings offered encouragement that biomarkers to predict FDG-PET/CT activity may show some promise and identified candidate biomarkers for further investigation in this regard.

Percutaneous core needle biopsies: the yield in spinal tuberculosis.

BACKGROUND: Current recommendations for spinal tuberculosis (TB) not requiring open surgery include core needle biopsy to confirm TB and determine drug sensitivity. International figures show the positive culture yield from core needle biopsies is 50 -- 83%.Objectives. To (i) assess the yield of percutaneous needle biopsies; (ii) identify factors that may lead to a negative result; and (iii) determine whether, TB being suspected, needle biopsy is justified. METHODS: We conducted a multicentre retrospective review of 44 patients treated for suspected spinal TB between January 2009 and April 2012, who did not require open surgery. Data captured included demographics, relevant history, outcome of investigations and histopathological findings in patients. RESULTS: The overall positive TB culture rate was 59%. Age, duration of symptoms, HIV and neurological status, erythrocyte sedimentation rate and core size had no statistical influence. Of the 7 patients receiving TB treatment at the time of biopsy, 3 were culture-positive. Multidrug resistance was evident in 12% of positive cultures. The positive culture yield was 40% at Tygerberg Hospital and 75% at Groote Schuur Hospital, with no difference in histological yield. This was attributed to the practice of decontaminating specimens prior to culture at Tygerberg Hospital. The highest culture yield (32%) came from samples showing non-necrotising chronic inflammatory changes. CONCLUSION: Percutaneous biopsy remains an important tool to diagnose and manage spinal TB. The yield of transpedicular biopsies in this study was comparable with international figures. Specimen decontamination prior to culture had a direct negative influence on biopsy culture yield, as did prior TB treatment.