Objectives Statin-associated immune-mediated necrotizing myopathy (IMNM) and idiopathic inflammatory myositis (IIM) are myopathies with overlapping features. This study compared the manifestations of IMNM to IIM in Native Americans. Method Twenty-one Native American patients with inflammatory myopathy (IM) were characterized as to diabetes mellitus, hyperlipidemia, statin exposure, myopathy diagnosis, muscle histology, autoimmune and myositis-specific autoantibodies, therapy, and outcome. Results IM consisted of 52.4% IMNM, 42.9% IIM, and 4.8% metabolic myopathy. IMNM vs. IIM had greater age (61.6±9.8 vs. 39.8±14.3 years), diabetes mellitus (100% vs. 55.6%), hyperlipidemia (100% vs. 33.3%), statin-exposure (100% vs. 22.2%), creatine kinase (CK) (11,780±7064 vs.1707±1658 IU), anti-HMG CoA reductase (anti-HMG CoA) antibodies (85.7% vs. 11.1%), and necrotizing IM (81.8% vs. 11.1%), but lesser disease duration (26.2±395 vs. 78.4±47.9 months), Raynaud’s phenomenon (9.1% vs. 55.6%), cutaneous manifestations (0% vs. 55.6%), antinuclear antibodies (18.2% vs. 66.7%), or any autoantibody (18.2% vs. 88.9%) (all p < 0.05). Magnetic resonance abnormalities, histologic IM, myositis-specific autoantibodies, pulmonary hypertension, esophageal dysfunction, interstitial lung disease, disability, and persistently elevated CK were similar. IMNM vs. IIM was treated more with intravenous immunoglobulin (72.7% vs. 11.1%, p = 0.009) and less with antimetabolites (45.5% vs. 88.9%, p = 0.05) and rituximab (18.2% vs. 55.6%, p = 0.09). Conclusions IMNM may occur in Native Americans and is associated with diabetes mellitus, hyperlipidemia, statin use, and older ages, and characterized by marked CK elevation, necrotizing myopathy, and anti-HMGCoA antibodies with few cutaneous or vascular manifestations.

ObjectiveTo update and validate the Rheumatic Disease Comorbidity Index (RDCI) utilizing International Classification of Diseases, Tenth Revision, Clinical Modification (ICD‐10‐CM) codes.MethodsWe defined ICD‐9‐CM (n = 1,068) and ICD‐10‐CM (n = 1,425) era cohorts (n = 862 in both) spanning the ICD‐9‐CM to ICD‐10‐CM transition in a multicenter, prospective rheumatoid arthritis registry. Information regarding comorbidities was collected from linked administrative data over 2‐year assessment periods. An ICD‐10‐CM code list was generated from crosswalks and clinical expertise. ICD‐9– and ICD‐10–derived RDCI scores were compared using intraclass correlation coefficients (ICC). The predictive ability of the RDCI for functional status and death during follow‐up was assessed using multivariable regression models and goodness‐of‐fit statistics (Akaike's information criterion [AIC] and quasi information criterion [QIC]) in both cohorts.ResultsMean ± SD RDCI scores were 2.93 ± 1.72 in the ICD‐9‐CM cohort and 2.92 ± 1.74 in the ICD‐10‐CM cohort. RDCI scores had substantial agreement in individuals who were in both cohorts (ICC 0.71 [95% confidence interval 0.68–0.74]). Prevalence of comorbidities was similar between cohorts with absolute differences <6%. Higher RDCI scores were associated with a greater risk of death and poorer functional status during follow‐up in both cohorts. Similarly, in both cohorts, models including the RDCI score had the lowest QIC (functional status) and AIC (death) values, indicating better model performance.ConclusionThe newly proposed ICD‐10‐CM codes for the RDCI‐generated comparable RDCI scores to those derived from ICD‐9‐CM codes and are highly predictive of functional status and death. The proposed ICD‐10‐CM codes for the RDCI can be used in rheumatic disease outcomes research spanning the ICD‐10‐CM era.

Clinical Images TextA 52-year-old woman with history of incomplete systemic lupus erythematosus (SLE) presented with worsening shortness of breath after being evaluated 10 days before an urgent care for cough and shortness of breath without hemoptysis. Her cough resolved, but increased shortness of breath brought her to the emergency department.The patient's D-dimer level was elevated at 809 ng/mL with subsequent chest computed tomography angiogram negative for pulmonary embolus. Computed tomography (CT) findings were significant for multiple pulmonary nodules with some demonstrating air bronchograms, and others demonstrating circumferential halos suggesting active infectious process (Fig. 1A-D). Her vitals were within normal limits, and other laboratory values were notable for normal white blood cell count, normal serum creatinine and urinalysis, microcytic anemia with hemoglobin of 8.1 g/dL, elevation in erythrocyte sedimentation rate to 78 mm/h, and Creactive protein level of 0.5 mg/dL, positive rheumatoid factor of 85 IU/mL, ANA titer of 1:2560 in a homogenous and nucleolar pattern, and anti-DNA titer of 1:160. Results of SS-A/SS-B testing were greater than 8.0 AI. The patient was discharged from the emergency department with a 4-week course of augmentin with plans to repeat chest CT upon completion of antibiotic course and outpatient rheumatology follow-up.At rheumatology appointment, SLE serologies were obtained due to family history of SLE in her mother and 2 sisters. sources relevant to the topic.