[An atypical presentation of tuberculosis]. / Een atypische presentatie van tuberculose.

BACKGROUND: In 2020 there were 623 known TB infections in the Netherlands according to the Dutch ministry of health (RIVM). About 4% were located in bones and joints. The incidence of Multi Drug Resistant (MDR) TB in The Netherlands is about 1%. CASE: We describe the case of a 46-year-old female with a painful and swelling of the mid phalangeal bone of the fourth left digit. Quantiferon was positive and PCR of the biopsy for Mycobacterium tuberculosis complex (MTC) in Ziehl-Neelsen staining confirmed tuberculous osteomyelitis. The strain was resistant for rifampicin, isoniazid, ethambutol and pyrazinamid classifying it as MDR. Treatment in a specialized center with second line drugs was indicated due to rare resistance. CONCLUSION: Tuberculosis may manifest anywhere throughout the body, also as an (atypical) swelling of the hand. The golden diagnostic standard for bone and joint TB is biopsy with Ziehl-Neelsen staining.

Baseline serum biomarkers of inflammation, bone turnover and adipokines predict spinal radiographic progression in ankylosing spondylitis patients on TNF inhibitor therapy.

OBJECTIVE: To analyze whether biomarker levels at baseline or their change after 3 months or 2 years predict radiographic spinal progression in ankylosing spondylitis (AS) patients treated with TNF-α inhibitors (TNFi). METHODS: 137 AS patients from the Groningen Leeuwarden Axial Spondyloarthritis (GLAS) cohort were included before starting TNFi. Serum biomarkers were measured at baseline, 3 months and 2 years: Markers of inflammation (calprotectin, matrix metalloproteinase-3, vascular endothelial growth factor), bone turnover markers (bone-specific alkaline phosphatase, serum C-terminal telopeptide fragments of type I collagen (sCTX), osteocalcin, osteoprotegerin, procollagen type I and II N-terminal propeptide, sclerostin) and adipokines (high-molecular-weight adiponectin, leptin, visfatin). Spinal radiographs were scored at baseline, 2 and 4 years. Logistic regression was performed to examine the association between biomarker values and radiographic spinal progression, adjusting for known risk factors for radiographic progression. RESULTS: Baseline calprotectin and visfatin levels were associated with mSASSS progression ≥2 points (OR 1.195 [95%CI 1.055-1.355] and 1.465 [1.137-1.889], respectively), while calprotectin was also associated with new syndesmophyte formation after 2 years (OR 1.107 [1.001-1.225]). Baseline leptin level was associated with mSASSS progression ≥4 points after 4 years (OR 0.614 [0.453-0.832]), and baseline sCTX level with syndesmophyte formation after 4 years (OR 1.004 [1.001-1.008]). Furthermore, change of visfatin and leptin levels over the first 2 years showed significant association with radiographic progression after 4 years. CONCLUSION: Independent of known risk factors, serum levels of biomarkers at baseline are able to predict radiographic spinal progression over 2 and 4 years in AS patients on TNFi therapy.

Change in disease activity is associated with TNF-α inhibitor serum levels in patients with axial spondyloarthritis in daily clinical practice.

OBJECTIVES: To investigate, in daily clinical practice, TNF-α inhibitor serum trough levels in patients experiencing an increase in axial spondyloarthritis (ax-SpA) related symptoms. Secondly, to explore if these serum trough levels are associated with disease activity (DA) and/or change in DA. METHODS: Patients from the GLAS cohort treated with TNF-α inhibitors who had a serum trough level measurement during follow-up because of an increase in ax-SpA related symptoms between June 2015 and June 2018 were included. Serum trough levels were stratified in a therapeutic and below therapeutic range, based on published reference values of Sanquin in 2019. DA was assessed by ASDAS and BASDAI and change in DA (i.e. ΔASDAS or BASDAI compared to the visit before increasing symptoms). RESULTS: 31 patients had a serum trough level measurement because of increasing symptoms. These patients had a median treatment duration of 4.8 years (IQR 0.9-8.6). 22 (71%) had active disease according to ASDAS (score ≥2.1) and 15 (47%) had therapeutic drug levels. The increase in DA was significantly larger in patients with below therapeutic drug levels compared to patients with therapeutic levels (ΔASDAS: 0.94±0.81 vs. -0.07±1.26, p<0.05; ΔBASDAI: 1.72±1.73 vs. -0.53±1.8, p<0.005). No significant differences were found in absolute DA scores between patients with or without therapeutic drug levels. CONCLUSIONS: In this observational study in daily clinical practice, approximately half of ax-SpA patients who experienced an increase in symptoms had below therapeutic TNF-α inhibitor serum trough levels. Change in DA and not absolute DA scores was significantly associated with drug levels.

Ankylosing spondylitis patients at risk of poor radiographic outcome show diminishing spinal radiographic progression during long-term treatment with TNF-α inhibitors.

OBJECTIVE: To investigate the influence of patient characteristics on the course of spinal radiographic progression in a large prospective longitudinal cohort study of ankylosing spondylitis (AS) patients treated long-term with TNF-α inhibitors. METHODS: Consecutive patients from the Groningen Leeuwarden AS (GLAS) cohort starting TNF-α inhibitors with spinal radiographs at least available at baseline and 6 years of follow-up were included. Radiographs were scored using mSASSS by two independent readers. Generalized estimating equations (GEE) were used to explore the associations between baseline characteristics and spinal radiographic progression. The course of radiographic progression in patients with and without risk factors for poor radiographic outcome was investigated using different time models (linear and non-linear). Single linear imputation was used in case of missing radiographic data at the intermediate (2 or 4 years) follow-up visits. RESULTS: 80 AS patients were included with mean baseline mSASSS 8.7±13.3. Baseline syndesmophytes, male gender, older age, longer symptom duration, smoking, and higher BMI were significantly associated with more radiographic damage over time. GEE analysis in patients with these risk factors revealed that radiographic progression followed a non-linear course with mean mSASSS progression rates reducing from max. 2.8 units over 0-2 years to min. 0.9 units over 4-6 years. The GEE model revealed a linear course with overall very low progression (≤1 mSASSS units/2yrs) in patients without risk factors. Complete case analysis in 53 patients showed similar results. CONCLUSION: AS patients at risk of poor radiographic outcome showed the highest but diminishing spinal radiographic progression during long-term treatment with TNF-α inhibitors.

Radiographic damage and progression of the cervical spine in ankylosing spondylitis patients treated with TNF-α inhibitors: Facet joints vs. vertebral bodies.

OBJECTIVES: To investigate radiographic damage and 4-year progression of the cervical facet joints in a prospective observational cohort of AS patients treated with TNF-α inhibitors, to compare this with damage and progression of the cervical vertebral bodies, and to study the relation with patient characteristics and clinical outcome. METHODS: Patients from the Groningen Leeuwarden AS (GLAS) cohort starting TNF-α inhibitors with baseline and 4-year radiographs were included. Cervical facet joints and vertebral bodies were scored by two independent readers according to the method of de Vlam and mSASSS, respectively. RESULTS: At baseline, 25 of 99 (25%) AS patients had partial or complete ankylosis of the cervical facet joints, whereas 51 (52%) patients had non-bridging or bridging syndesmophytes of cervical vertebral bodies. During 4 years, 13 (13%) patients developed new (partial) ankylosis of the facet joints, whereas 26 (26%) developed new (bridging) syndesmophytes. Facet joint damage and progression without involvement of the vertebral bodies were seen in 5 (5%) and 8 (8%) patients, respectively. Damage of facet joints was associated with longer disease duration, history of IBD/uveitis/psoriasis, higher disease activity, larger occiput-to-wall distance, higher mSASSS, and presence of syndesmophytes. Progression of the facet joints was associated with larger occiput-to-wall distance and more facet joint damage at baseline. CONCLUSIONS: Cervical facet joints were frequently involved in AS. During 4 years of TNF-α blocking therapy, 13% of the patients showed radiographic progression of cervical facet joints of which the majority did not show progression of vertebral bodies.

Clinical Risk Factors for the Presence and Development of Vertebral Fractures in Patients With Ankylosing Spondylitis.

INTRODUCTION: To investigate the prevalence and incidence of radiographic vertebral fractures and the association with patient characteristics, clinical assessments, and medication use in a large prospective cohort of patients with ankylosing spondylitis (AS) in daily clinical practice. METHODS: Consecutive AS patients from the Groningen Leeuwarden AS (GLAS) cohort with baseline and 2-year lateral radiographs of the thoracic and lumbar spine were included. Radiographs were scored for vertebral fractures by 2 readers according to the method of Genant et al. Differences in baseline characteristics between patients with and without radiographic vertebral fractures were explored. RESULTS: Of 292 included AS patients, 59 (20%) had radiographic vertebral fractures at baseline, 15 (6%) developed new fractures, and 7 (2%) showed an increase in the severity of existing fractures during 2 years of follow-up. Most fractures were mild and located in the midthoracic and thoracolumbar region of the spine. The presence of vertebral fractures was significantly associated with older age, higher body mass index, longer smoking duration, larger occiput-to-wall distance, more spinal radiographic damage, and lower hip bone mineral density (BMD). The development of new or progressive vertebral fractures was also associated with older age and low BMD. Patients using nonsteroidal antiinflammatory drugs (NSAIDs) at baseline showed less prevalent and incident vertebral fractures. CONCLUSION: In this large AS cohort in daily clinical practice, radiographic vertebral fractures were frequently present in AS, especially in older patients with more advanced disease, low hip BMD, and a less healthy lifestyle. Interestingly, NSAID use was associated with a reduced vertebral fractures risk.

Reduction in Spinal Radiographic Progression in Ankylosing Spondylitis Patients Receiving Prolonged Treatment With Tumor Necrosis Factor Inhibitors.

OBJECTIVE: To evaluate the course of spinal radiographic progression for up to 8 years of followup in a large cohort of ankylosing spondylitis (AS) patients treated with tumor necrosis factor (TNF) inhibitors. METHODS: Consecutive patients from the Groningen Leeuwarden AS cohort starting TNF inhibitors between 2004 and 2012 were included. Baseline and biannual radiographs were randomized with radiographs of TNF-naive AS patients and scored in chronologic order according to modified Stoke Ankylosing Spondylitis Spine Score (mSASSS). The course of radiographic progression (linear or nonlinear) was investigated using generalized estimating equations. Primary analysis was performed in patients with complete data over 4, 6, and 8 years of followup. Sensitivity analysis was performed after single linear imputation of missing radiographic data and after adjusting for patient characteristics with possible influence on radiographic progression. RESULTS: At baseline, median mSASSS of 210 included AS patients was 2.8 (interquartile range 0.0-12.0), mean ± SD mSASSS 10.0 ± 15.5. During the first 4 years, radiographic progression followed a linear course (estimated mean progression rate was 1.7 for 0-2 and 2-4 years). A deflection from a linear course was found in patients with complete and imputed data over 6 and 8 years. The estimated mean 2-year progression rate reduced from 2.3 to 0.8 in patients with complete 8-year data. The same pattern was found after adjustment for baseline mSASSS scores, presence of syndesmophytes, sex, HLA-B27 status, age, symptom duration, smoking duration, body mass index, disease activity, and nonsteroidal antiinflammatory drug use. CONCLUSION: This observational cohort study in AS patients receiving long-term TNF inhibitors showed a reduction in spinal radiographic progression after more than 4 years of followup.