Assessment of disease activity in patients with rheumatoid arthritis using optical spectral transmission measurements, a non-invasive imaging technique.

OBJECTIVES: In rheumatoid arthritis (RA), treat-to-target strategies require instruments for valid detection of joint inflammation. Therefore, imaging modalities are increasingly used in clinical practice. Optical spectral transmission (OST) measurements are non-invasive and fast and may therefore have benefits over existing imaging modalities. We tested whether OST could measure disease activity validly in patients with RA. METHODS: In 59 patients with RA and 10 patients with arthralgia, OST, joint counts, Disease Activity Score (DAS) 28 and ultrasonography (US) were performed. Additionally, MRI was performed in patients with DAS28<2.6. We developed and validated within the same cohort an algorithm for detection of joint inflammation by OST with US as reference. RESULTS: At the joint level, OST and US performed similarly inproximal interphalangeal-joints (area under the receiver-operating curve (AUC) of 0.79, p<0.0001) andmetacarpophalangeal joints (AUC 0.78, p<0.0001). Performance was less similar in wrists (AUC 0.62, p=0.006). On the patient level, OST correlated moderately with clinical examination (DAS28 r=0.42, p=0.001), and US scores (r=0.64, p<0.0001). Furthermore, in patients with subclinical and low disease activity, there was a correlation between OST and MRI synovitis score (RAMRIS (Rheumatoid Arthritis MRI Scoring) synovitis), r=0.52, p=0.005. CONCLUSIONS: In this pilot study, OST performed moderately in the detection of joint inflammation in patients with RA. Further studies are needed to determine the diagnostic performance in a new cohort of patients with RA.

Natural course of bone marrow oedema on magnetic resonance imaging of the sacroiliac joints in patients with early inflammatory back pain: a 2-year follow-up study.

OBJECTIVES: To describe the distribution and evolution over time of bone marrow oedema (BME) on magnetic resonance imaging of the sacroiliac joint (MRI-SIJ) in patients with recent-onset inflammatory back pain (IBP) suspected for axial spondyloarthritis (axSpA). METHOD: A 2-year follow-up study with annual MRI-SIJ was conducted in patients with IBP of duration ≤ 2 years. Each SIJ was divided into quadrants and MRI scores were analysed on a per-patient and per-SIJ quadrant basis. The presence of BME in each SIJ quadrant was recorded. Fulfilment of the Assessment of SpondyloArthritis international Society (ASAS) criteria for axSpA was assessed at baseline and at follow-up. RESULTS: At baseline, 68 patients (38% male; mean age 34.9 ± 10.3 years) were included. BME was visible at baseline in 24 (35%) patients, all fulfilling the ASAS axSpA criteria. Twenty-three of these 24 patients had a follow-up MRI. Not taking into account the baseline MRI, three (13%) of these 23 patients would no longer fulfil the ASAS criteria during follow-up because of subsiding BME. Forty-four (65%) patients had a negative baseline MRI, of whom 39 had a follow-up MRI available. New BME at follow-up meant that three (8%) of these 39 patients now fulfilled the ASAS criteria. At follow-up, baseline BME lesions subsided completely in 47% of SIJ quadrants (range 33-71%) whereas new BME lesions were detected in 8% of SIJ quadrants (range 2-11%). CONCLUSIONS: BME shows a fluctuating course in patients with early IBP suspected for axSpA. This may have an impact on diagnosis and the overall performance of the ASAS axSpA criteria.

Gadolinium contrast-enhanced MRI sequence does not have an incremental value in the assessment of sacroiliitis in patients with early inflammatory back pain by using MRI in combination with pelvic radiographs: a 2-year follow-up study.

OBJECTIVES: To evaluate the potential incremental value in detecting sacroiliitis of the T1 post-gadolinium diethylenetriaminepenta-acetic acid (Gd-DTPA) MRI sequence of the sacroiliac joints (SIJ) compared with the combination of short tau inversion recovery (STIR) MRI sequence and pelvic radiographs in patients with inflammatory back pain (IBP) suspected for axial spondyloarthritis. METHODS: A 2-year follow-up study was conducted in patients with IBP of less than 2 years duration. Annual MRI of the SIJ (MRI-SIJ) was performed and scored for bone marrow oedema (BME). Pelvic radiographs were scored according to the modified New York (mNY) criteria. Agreement on the presence of BME detected by the STIR and post-Gd-DTPA sequence and the incremental value of post-Gd-DTPA sequence over STIR plus radiographs was analysed by descriptive methods and kappa statistics. RESULTS: At baseline, 20 (29%) out of 68 patients (38% male; mean (SD) age 34.9 (10.3) years) enrolled had BME both on the STIR and post-Gd-DTPA sequences; 4 patients (6%) on the STIR sequence only; none on the post-Gd-DTPA sequence only (kappa value: 0.87). Fifteen (22%) patients fulfilled the mNY criteria at baseline. Sixty-two (91%) patients had at least 1 follow-up MRI-SIJ. At 2-year follow-up, 2 patients had BME on the post-Gd-DTPA sequence without BME on the STIR sequence. These 2 patients already fulfilled the mNY criteria at baseline. CONCLUSIONS: In this cohort of patients with early IBP, the post-Gd-DTPA sequence of the MRI-SIJ did not have an incremental value in the detection of sacroiliitis compared with the STIR sequence plus pelvic radiographs.

HLA-B27 and gender independently determine the likelihood of a positive MRI of the sacroiliac joints in patients with early inflammatory back pain: a 2-year MRI follow-up study.

OBJECTIVES: To describe how inflammation on MRI of the sacroiliac joints in patients with recent-onset inflammatory back pain (IBP) evolves over time, and to study determinants of activity on MRI of the sacroiliac joint. METHODS: A 2-year follow-up study with annual MRI of the sacroiliac joints was conducted in patients with IBP of less than 2 years' duration. Images were scored for bone marrow oedema on short τ inversion recovery and enhancement after administration of gadolinium on T1. RESULTS: Of the 68 patients (38% male; mean age 34.9 ± 10.3 years) enrolled, 44 had a negative baseline MRI. Of these 44 patients, 39 patients had at least one follow-up MRI of whom six patients (15%) developed activity on MRI during follow-up. 24 patients (35%) had an abnormal MRI at baseline. In 23 of these 24 patients follow-up MRI was available. The MRI became negative in seven of these 23 patients (30%) during follow-up. Human leucocyte antigen B27 (HLA-B27) positivity and male gender determined independently the likelihood of a positive MRI at any time point. In an HLA-B27-positive patient the likelihood of a positive MRI during follow-up is 88% if the baseline MRI is positive and 27% if the baseline MRI is negative. In an HLA-B27-negative patient with a negative MRI at baseline the likelihood of a positive MRI during follow-up is less than 5%. CONCLUSIONS: A positive MRI at baseline predicts a positive MRI during follow-up in HLA-B27-positive patients. A negative MRI at baseline in HLA-B27-negative patients strongly predicts a negative MRI during follow-up.

One-sided limb lymphedema in a liver transplant recipient receiving sirolimus.

Sirolimus (SRL) is associated with many side effects including hypercholesterolemia, anaemia, impaired wound healing and abnormal liver function tests. Limb lymphedema has only been reported several times in renal transplant recipients. We present a case of lower limb lymphedema that occurred in a 59-year-old liver transplant recipient after being on a SRL regimen for seven months. Extensive diagnostic investigations could not reveal signs of infection, venous obstruction or malignancy. After discontinuation of SRL, the lymphedema gradually resolved during the next three months. The pathologic mechanism behind this phenomenon is unknown, but antiangiogenetic and antiproliferative properties of SRL have been hold responsible. Further studies are necessary to explain this rare side effect.