A novel diagnostic method (spectral computed tomography of sacroiliac joints) for axial spondyloarthritis.

BACKGROUND/PURPOSE: To evaluate the diagnostic value of spectral computed tomography (CT) of sacroiliac joints for axial spondyloarthritis (SpA). METHODS: We retrospectively analyzed the records of 125 patients with low back pain (LBP) suspected of having SpA. Each patient underwent sacroiliac joint spectral CT examination. Water- and calcium-based material decomposition images were reconstructed. After 3-6 months of follow-up, 76 were diagnosed with SpA, and the remaining 49 patients were diagnosed with nonspecific LBP (nLBP). The slope of sacroiliac bone marrow HU (Hounsfield unit) curve (λHU), CT value, and bone marrow to normal muscle ratios of water and calcium concentrations in the ilium and sacrum were calculated and compared between nLBP and SpA patients. RESULTS: The iliac λHU was 8.26 ± 3.91 for nLBP and 9.81 ± 4.92 for SpA. The mean iliac ratios of water and calcium concentrations were 1.04 ± 0.03 and 21.67 ± 4.40, respectively, for nLBP, and 1.07 ± 0.04 and 111.5 ± 358.98, respectively, for SpA. The mean iliac CT values were 311.12 ± 86.52 HU for nLBP and 423.97 ± 127.51 HU for SpA. There were statistically significant differences in iliac ratios of water and calcium concentrations, CT value, and λHU between nLBP and SpA patients (p < 0.05). The sensitivity of iliac λHU was the highest. The diagnostic odds ratio of ratio of iliac calcium concentration was the highest, and its negative likelihood ratio was the lowest. CONCLUSION: Spectral CT not only shows bone erosion and sclerosis, but also shows and quantitatively measures bone marrow edema in the sacroiliac joints of SpA patients.

Comparing the diagnostic utility of sacroiliac spectral CT and MRI in axial spondyloarthritis.

OBJECTIVE: To compare the clinical value of sacroiliac spectral CT and MRI in diagnosing axial spondyloarthritis (SpA). METHODS: 137 patients with low back pain and suspected axial SpA were recruited. 76 patients were diagnosed with axial SpA, and 49 patients were diagnosed with non-specific low back pain (nLBP). Each patient underwent spectral CT and MRI examinations of the sacroiliac joints. Water- and calcium-based material decomposition images were reconstructed for quantitative analysis. The marrow-to-muscle ratios of water and calcium concentrations and short tau inversion recovery (STIR) signal intensity, as well as Hounsfield units in the ilium and sacrum were compared between nLBP and patients with axial SpA. RESULTS: Spectral CT is comparable with MRI for the detection of bone marrow oedema, and it is superior to MRI for detection of osseous sclerosis and erosions. MRI is superior to spectral CT in detecting enthesitis and synovitis. There were statistically significant differences in STIR signal intensity, water concentration and calcium concentration ratios as well as CT values between nLBP and patients with axial SpA (p < 0.05) in the ilium. There was a statistically significant but weak correlation between ratios of water concentration and STIR signal intensity in both the ilium and sacrum (p < 0.05). Overall, the iliac water concentration was most sensitive for detection of patients with SpA. The positive likelihood ratio of the STIR signal intensity ratio was the highest. The diagnostic odds ratio of the calcium concentration ratio was the highest, and its negative likelihood ratio was the lowest. CONCLUSION: Spectral CT not only depicts findings of chronic sacroiliitis (i.e. bone erosion and sclerosis), but also can detect and quantify the extent of marrow oedema in patients with SpA with activity sacroiliitis. The sensitivity of MRI for diagnosis of early synovitis and enthesitis remains superior. The combination of spectral CT and MRI may thus improve diagnostic accuracy in the diagnosis of axial SpA. ADVANCES IN KNOWLEDGE: Spectral CT can measure both calcium and water concentration of the sacroiliac joints. The combination of spectral CT and MRI may thus improve diagnostic accuracy in the diagnosis of axial SpA.

[Incidence of metabolic disorders in patients with essential hypertension and patients with primary aldosteronism].

OBJECTIVE: To compare the incidence of metabolic disorders (MS) in patients with primary aldosteronism (PA) and essential hypertension (EH). METHODS: MS prevalence was observed in 200 EH patients (male 104) and 220 PA patients (male 117) hospitalized to our hospital from August 2005 to March 2007. RESULTS: (1) The prevalence of MS in PA group was significantly higher than that of EH group (47.3% vs. 31.5%, P = 0.009). (2) Blood pressure was significantly higher in PA group than that of EH [SBP: (150.67 +/- 15.45) mm Hg vs. (145.69 +/- 17.13) mm Hg, P = 0.042; DBP: (93.03 +/- 10.51) mm Hg vs. (85.83 +/- 14.44) mm Hg, P = 0.037]. (3) Incidences of abdominal obesity (86.8% vs. 78.5%, P = 0.024) and insulin resistance (insulin sensitivity index: 42.42 +/- 16.11 vs. 49.58 +/- 22.43, P = 0.008) were significantly higher in PA group than in EH group. CONCLUSION: The prevalence of MS in hospitalized PA patients was significantly higher than that of EH patients characterized by prevalent abdominal obesity, insulin resistant and severe hypertension.

Safety evaluation of a canine hepatitis DNA vaccine.

DNA vaccines are a novel disease prevention methodology, however their safety has not been well described. We evaluated the safety and efficacy of the DNA vaccine pVAX1-CpG-Loop against infectious canine hepatitis. We demonstrated that pVAX1-CpG-Loop could not be recovered from tissues of vaccinated mice nor from F1 progeny and following vaccination there were no apparent changes in hematologic markers compared to unvaccinated controls. Most important, vaccinated mice were protected from viral challenge. The only detectable effects of the vaccination were elevated AST levels 4 weeks post vaccination and liver lymphocyte infiltration and hydropic degeneration which normalized 6 months later.