The Low Prevalence of Inclusion Body Myositis in an Outpatient Rheumatology Myositis Cohort.

Introduction Sporadic inclusion body myositis (IBM) is a rare type of myopathy of unknown etiology typified by the presence of distinctive muscle fiber inclusions. IBM belongs to a larger family of conditions called the idiopathic inflammatory myopathies (IIM). This study seeks to compare the prevalence, clinical manifestations, and disease course of IBM patients to a cohort of polymyositis (PM) and dermatomyositis (DM) patients in an outpatient rheumatology myositis cohort. Methods We conducted a retrospective chart review of all adult patients attending rheumatology clinics at the Cook County Hospital from 2006 to 2011 with the International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9) diagnoses of idiopathic inflammatory myopathies (IIM). Data collected included patient demographics, serial muscle strength testing, serial creatine kinase (CK), muscle biopsies, and immunosuppressive therapies received.  Results We identified 112 patients with IIM with the following breakdown: 66 - dermatomyositis, 42 - polymyositis, and four - IBM. These four patients represent the primary cohort. They had a mean age of 67 years (range 62-74), the mean follow-up period of 15 months (range 3-47), mean initial muscle strength in the weakest group of 3.75 (range 2-5, standard deviation [SD]=1.3), mean initial CK of 1,968 U/L (range 313-4,795, SD=1,970), mean final muscle strength in the weakest group of 3.75 (range 3-4, SD=0.5), mean final CK of 1,326 U/L (range 213-2,943, SD=1,200). Conclusions Our IBM patients had many features similar to other described IBM cohorts, including older age, male predominance, slow progression (stable CK and muscle strength), and lack of response to immunosuppressive therapy. Interestingly, we found a low prevalence of IBM in our outpatient rheumatology IIM cohort.

Pulse Dose Methylprednisolone Therapy for Adult Idiopathic Inflammatory Myopathy.

Idiopathic inflammatory myopathies (IIM) are a rare group of autoimmune diseases characterized by muscle inflammation. Typically high-dose daily oral corticosteroids are used as the first-line therapy of IIM. Pulse dose intravenous methylprednisolone (IVMP) has been used for serious or refractory cases. Here, we systematically analyze the therapeutic effect of pulse dose IVMP in patients with IIM in a large municipal safety net medical center and review the literature on pulse IVMP in adult IIM. We conducted a retrospective chart review of patients who were diagnosed with IIM in the rheumatology clinics of the Cook County Health and Hospital Systems. Data collected included patient demographics, diagnosis, immunosuppressive therapies, serial serum creatine kinase (CK) measurements, and serial muscle strength testing. Seven patients received pulse dose IVMP for active myositis. At the time of pulse dose IVMP, the mean strength in the weakest muscle group was rated as 3.1 of 5 (range, 2-4; SD, 0.9) and the mean peak CK was 5746 U/L (range, 1602-14,039; SD, 4911). Dysphagia was reported in 5 of the 7 patients at the time of IVMP. Four to six weeks after IVMP, the mean strength in the weakest muscle group was 3.3 of 5 (range, 1-5; SD, 1.5) and mean peak CK was 1064 U/L (range, 63-1788, SD, 712). Four to six weeks after IVMP, dysphagia had resolved in 2 and improved in 3. At the end of follow-up, mean strength in the weakest muscle group was 4.7 of 5 (range, 4-5; SD, 0.5), mean peak CK was 480 U/L (range, 37-1016; SD, 337), and the mean prednisone dosage was 15 mg (range, 2.5-60; SD, 21). Although our study has certain limitations, our cohort of adult patients with IIM had marked improvement in clinical and biochemical outcomes. Four to six weeks after IVMP infusion, there was a rapid improvement in muscle enzyme levels, muscle strength, and dysphagia. This therapy warrants further controlled trials.

Corticosteroid Monotherapy Is Usually Insufficient Treatment for Idiopathic Inflammatory Myopathy.

Idiopathic inflammatory myopathies (IIM) are a rare group of autoimmune diseases characterized by muscle inflammation. High-dose corticosteroids are conventionally used as the first-line therapy for IIM, but early introduction of noncorticosteroid immunosuppressive agents has become increasingly common in recent years despite a paucity of compelling evidence to support this. Here, we systematically analyze therapeutic practice patterns of IIM in a large municipal safety net medical center. We conducted a retrospective chart review of all adult patients attending rheumatology clinics at the Cook County Health and Hospital Systems from 2006 to 2011 with a diagnosis of IIM. Data collected included patient demographics, diagnosis, immunosuppressive therapies, serial serum creatine kinase (CK) measurements, and serial muscle strength testing. One hundred eight patients fulfilled eligibility criteria. The mean duration of follow-up was 62 months (range, 1-351 months). At presentation, the mean strength in the weakest muscle group was rated as 3.6 out of 5 (range, 1-5; SD 0.9), the mean initial CK was 4720 U/L (range, 23-38, 461; SD 6, 795), and initial mean prednisone dosage was 48 mg/d (range, 0-100, SD 22). At the end of the follow-up period, mean strength in the weakest muscle group was 4.6 out of 5 (range, 2-5; SD 0.7), mean peak CK was 412 (24-7533; SD 875), and the mean prednisone dosage was 12.7 mg (0-80; SD 17.5). Only 15 patients (14%) received exclusively corticosteroid monotherapy during the follow-up period. Ninety-three patients (86%) received additional immunosuppressive agents. Over the course of their illness, only a minority of patients in our cohort of IIM patients was treated with corticosteroids alone. It is unlikely we will determine optimal therapy in the absence of a large controlled study comparing corticosteroids versus a combination regimen, but it seems that rheumatologists favor addition of second-line immunosuppressive agents.

Serum transaminases are frequently elevated at time of diagnosis of idiopathic inflammatory myopathy and normalize with creatine kinase.

INTRODUCTION: Despite multiple reports of elevated transaminases in muscle injury, aspartate aminotransferase (AST) and alanine aminotransferase (ALT) are not always considered indicators of muscle damage. The purpose of this study was to examine the relationship between serum AST, ALT, and creatine kinase (CK) levels at time of diagnosis of idiopathic inflammatory myopathy (IIM) and at the time of CK normalization. METHODS: We conducted a retrospective chart review of all adult patients attending rheumatology clinics at a county hospital with a diagnosis of IIM. Data collected included patient demographics, serial CK measurements, and serial serum transaminase measurements. RESULTS: We identified 85 patients with IIM. At myositis presentation, 75 (88%) had CK above the upper limit of normal (ULN), 72 (85%) had AST above the ULN, and 68 (80%) had ALT above the ULN. The average CK was 5302 U/L (range, 23-38,461 U/L [SD, 7096]), average AST 215 U/L (range, 16-1270 [SD, 227]), and average ALT 137 U/L (range, 10-621 [SD, 137]). The average AST and ALT at first available normalized CK was 26 U/L (range, 9-139 [SD, 18]) and 26 U/L (range, 5-96 [SD, 19]). We found a strong correlation between CK and AST (r= 0.832; P < 0.001) and ALT (r = 0.775; P < 0.001) at initial presentation and also at the time of peak CK levels (r = 0.874 [P < 0.001] and r = 0.842 [P < 0.001], respectively). CONCLUSIONS: In our series, we found a strong correlation between CK and serum transaminases. Serum transaminases were elevated in 80% of patients at the time of presentation and normalized in 85% of the patients at the time of CK normalization. Appropriate recognition of these laboratory changes in IIM may help reduce unnecessary hepatic evaluation, delayed diagnosis, unnecessary avoidance of second line immunosuppressants, and misdiagnosis of primary liver disease.

Pseudo-septic hip arthritis as the presenting symptom of ankylosing spondylitis: a case series and review of the literature.

INTRODUCTION: Ankylosing spondylitis (AS) typically presents with inflammatory back pain and stiffness, but severe hip involvement may also be present. In this study, we evaluated the frequency of severe hip arthritis mimicking septic arthritis as initial presenting symptom of AS. METHODS: Utilising billing records, we retrospectively studied all AS patients seen from the years 2006 to 2009 at our institution. The primary endpoint was severe hip arthritis mimicking septic arthritis as the initial presenting symptom of AS. RESULTS: A total of 121 AS patients were identified from billing records, of whom 3 had severe hip arthritis mimicking septic arthritis as the initial presenting symptom of ankylosing spondylitis. CONCLUSIONS: Our study highlights the importance of including AS in the differential diagnosis of severe acute inflammatory hip arthritis in young adults, even when the onset appears to be abrupt.