Autoantibodies to Mi-2 alpha and Mi-2 beta in patients with idiopathic inflammatory myopathy

OBJECTIVES

The objective of this study was to compare the results obtained from different assays for the detection of anti-Mi-2 antibodies, which are important markers in the diagnosis of DM.

METHODS

The study included 82 patients (68 females/14 males), most of whom had DM (n = 57), followed by PM (n = 16) and juvenile DM (n = 9). All samples were tested using a novel particle-based multi-analyte technology (PMAT) (Inova Diagnostics, research use only) in parallel with a line immunoassay (LIA: Euroimmun). To assess clinical specificity for the PMAT assay, a total of 775 disease and healthy controls were tested.

RESULTS

29 samples were positive by at least one test for anti-Mi-2 antibodies. Of those, 24 were Mi-2β LIA+, five were Mi-2α LIA+ and 23 Mi-2 PMAT+. The comparison shows varying agreement between the different methods (kappa 0.27-0.77). When LIA results were used as reference for receiver operating characteristics analysis, high area under the curve values were found for both PMAT vs LIA Mi-2α and LIA Mi-2β. When analysing the results in the context of the myositis phenotype, PMAT associated closest with the DM phenotype. In the control group, 3/775 controls (all low levels) were anti-Mi-2+ resulting in a sensitivity and specificity of 28.1% and 99.6%, respectively.

CONCLUSION

Overall, good agreement was found between LIA and PMAT for anti-Mi-2 antibodies, which is important for the standardization of autoantibodies. Anti-Mi-2β antibodies measured by PMAT tend be more highly associated with the clinical phenotype of DM.

Educational impact of a clinical anatomy workshop on 1st-year orthopedic and rheumatology fellows in Mexico City

We aim to study the educational impact of a clinical anatomy workshop in 1st-year orthopedic and rheumatology fellows. First-year rheumatology fellows (N = 17) and a convenience sample of 1st-year orthopedic fellows (N = 14) from Mexico City in the 9th month of training participated in the study. The pre- and the post- workshop tests included the same 20 questions that had to be answered by identification or demonstration of relevant anatomical items. The questions, arranged by anatomical regions, were asked in five dynamic stations. Overall, the 31 participants showed an increase of correct answers, from a median of 6 (range 1 to 12) in the pre-workshop test, to a median of 14 (range 7 to 19) in the post-workshop test. In the pre-workshop test, the correct median answers were 7 (range 2 to 12) in the orthopedic fellows and 5 (range 1 to 10) in the rheumatology fellows (p = 0.297). Corresponding scores in the post-workshop were 15 (range 10 to 19) and 12 (range 7 to 18) (p = 0.026) showing a significant difference favoring the orthopedic group. Our clinical anatomy workshop was efficacious, in the short term, as a teaching instrument for 1st-year orthopedic and rheumatology fellows. The post-workshop scores, although significantly improved in both groups, particularly in the orthopedic fellows, were still suboptimal. Further refinements of our workshop might yield better results.

Primigravida is associated with flare in women with systemic lupus erythematosus

The objective of this study was to identify risk factors associated with flare during pregnancy in women with systemic lupus erythematosus (SLE). We performed a retrospective analysis of pregnant women with SLE in a referral hospital. Flare was considered according to predetermined definitions. We analyzed 15 clinical, biochemical and immunological variables with a potential predictive value for relapse during pregnancy. We included 124 lupus pregnancies in 120 women. The relapse rate during pregnancy was 37.9% (47 episodes). The most common manifestations of flare were renal, joint, cutaneous and hematological. Patients with flare during pregnancy developed a higher frequency of preeclampsia and preterm delivery. In multivariate analysis, primigravida was a risk factor associated with any type of flare during pregnancy (OR 2.3, 95% CI 0.99-5.52, p = 0.05); on the other hand, primigravida (OR 3.6, 95% CI 1.19-11.3, p = 0.02), activity prior to pregnancy (OR 3.7, 95% CI 0.97-14.1, p = 0.05), and previous renal disease (OR 5.8, 95% CI 1.95-17.6, p = 0.001) were the principal risk factors associated with renal flare. The first pregnancy in women with SLE is associated with any type of flare. Disease activity is associated with preeclampsia and preterm delivery. Close monitoring is mandatory to identify relapses and timely treatment.

Prevalence of community-acquired and nosocomial infections in hospitalized patients with systemic lupus erythematosus

Infections are an important cause of morbidity and mortality in systemic lupus erythematosus. We aimed to determine the incidence and characteristics of infections in patients hospitalized because of systemic lupus erythematosus, and to identify which factors influence their outcome. The medical records of patients with systemic lupus erythematosus hospitalized between January 2002 and December 2007 were reviewed according to a standardized case form including demographic, clinical, and therapeutic data. The diagnosis of infection was based on clinical findings, the identification of the causative agent or response to antibiotic treatment. The study included 473 patients (mean age 30 +/- 11 years; 421 (89%) female) who were hospitalized for a mean of 13 +/- 9 days. A community-based infection was suspected in 268 (57%) at admission; the diagnosis was confirmed in 96 patients (22%) and ruled out in 20 (4.2%); nevertheless, 152 patients (32%) received antibiotics on an empirical basis. A nosocomial infection was suspected in 63 (13.3%) of 453 patients and was confirmed in 59 (12.5%). The two most common community-acquired and nosocomial infections affected the respiratory and genitourinary tracts. Gram-negative bacteria were major etiological agents isolated. In the multivariate analysis, community-based infections associated with mucocutaneous, renal, or central nervous system disease activity as well as fever, and Mex-SLEDAI at admission and nosocomial infections to azathioprine use, infection at admission, disease duration, and hospitalization >7 days. We conclude that infections are an important cause of hospitalization of systemic lupus erythematosus patients. Risk factors include disease activity, use of immunosuppressants, disease duration, and length of hospital stay.