Treatment of inflammatory myopathies

The treatment of the immune-mediated inflammatory myopathies remains largely empirical. Corticosteroids are usually effective in polymyositis and dermatomyositis but may need to be combined with methotrexate or azathioprine in some patients. Intravenous immunoglobulin (IVIg) is effective as add-on therapy in some patients not adequately controlled with steroids or immunosuppressive agents, but further controlled trials of IVIg are necessary to define the indications and optimal dose regimens. Cyclophosphamide, cyclosporin, or chlorambucil may be effective in patients with refractory polymyositis or dermatomyositis. Low-dose whole body or lymphoid irradiation is a last option in severely disabled patients resistant to all other treatments. As a small proportion of patients with inclusion body myositis respond to corticosteroid or immunosuppressive therapy, a 3-6-month trial of such therapy is justified in this condition. More specific immunotherapy for these disorders awaits identification of the target antigens and further clarification of the immunopathogenetic mechanisms.

Inflammatory myopathies: issues in diagnosis and management

The techniques of magnetic resonance imaging and spectroscopy have been shown to have utility in the diagnosis and management of inflammatory muscle diseases. But perhaps more important have been the new insights into the pathophysiology of these diseases which MR studies, along with new immunologic data on autoantibodies and cellular infiltrates, have afforded. Pathologic subsets of inflammatory muscle disorders have been identified, suggesting, for example, that PM and DM are distinct disorders, thereby challenging the idea that these are relatively homogeneous syndromes. Further insights into disease pathogenesis which are likely to emerge from these new findings may allow identification of etiologic factors and improved approaches to treatment.

Toxoplasmic myocarditis and polymyositis in patients with acute acquired toxoplasmosis diagnosed during life

The presence of both toxoplasmic myocarditis and myositis in the same individual has been reported only at autopsy. We report the first case of biopsy-proven toxoplasmic myocarditis and polymyositis simultaneously occurring in the same individual that was diagnosed during life. Results of her toxoplasmic serology were consistent with acute toxoplasmosis. She subsequently developed visual symptoms consistent with toxoplasmic chorioretinitis. She had a positive clinical response to therapeutic agents specific against Toxoplasma gondii. Her toxoplasmic serological profile established the diagnosis of acute toxoplasmosis. A toxoplasmic serological profile should be obtained for patients with myocarditis and/or polymyositis of unclear etiology. Endomyocardial or skeletal muscle tissue biopsies may establish the definitive diagnosis of toxoplasmic myocarditis or polymyositis, respectively. Examination of blood by polymerase chain reaction analysis before antitoxoplasmic treatment and early in the course of primary infection with T. gondii may prove useful.

[Established and new therapeutic approaches in dermatomyositis, polymyositis and overlapping syndromes]

An overview is presented on current antiinflammatory, cytostatic/cytotoxic and immunomodulatory treatments for immunologically mediated inflammatory myopathies with skin involvement. High-dose intravenous immunoglobulin (IVIG) therapy is discussed in the context of recent findings regarding pathogenic mechanisms of autoimmune diseases.

Case report: polymyositis-induced myoglobinuric acute renal failure

Polymyositis rarely leads to myoglobinuric acute renal failure. One such case is reported here, and certain common features in reported cases are discussed. Given therapeutic advances, these patients should do well despite the dismal prognosis reported in the literature, but early diagnosis and prompt treatment are essential.

Intravenous immunoglobulin therapy for refractory myositis

The efficacy of polyvalent intravenous immunoglobulin therapy (IVIG) was evaluated in three patients with refractory myositis. Patients refractory to conventional therapy, such as corticosteroid administration, corticosteroid or cyclophosphamide pulse therapy [2 with dermatomyositis (DM), 1 with polymyositis (PM)] were treated with IVIG (0.4 g/kg daily) for 5 days. Clinical improvement was apparent within 1-2 months after IVIG and persisted for 19-23 months (DM patients) and 12 months (PM patient). No adverse effects were observed. Thus, IVIG may be considered an effective therapy for refractory myositis.

Long-term prognosis of 69 patients with dermatomyositis or polymyositis

OBJECTIVES

To assess the long-term prognosis of dermatomyositis and pol myositis.

METHODS

69 patients with dermatomyositis or polymyositis were selected according to the diagnostic criteria of Bohan and Peter and were followed up for a minimum of 6.3 years (for surviving patients) (mean 11.6 years). Clinical and biological features, and pulmonary and muscle parameters were considered as prognostic factors for death. Functional disability was assessed using a 4-stage grading system.

RESULTS

30 deaths (43.5%) occurred mainly due to cardiovascular (8), pulmonary (8), carcinomatous (5) and iatrogenic complications (5). Survival rates were 82.6% at 1 year, 73.9% at 2.66, 7% at 5 and 55.4% at 9. Significant prognostic factors for death (Cox model with time-dependent covariates) were old age (p < 0.0001), dysphonia (p < 0.001), pulmonary interstitial fibrosis (p < 0.02), absence of dysphagia (p < 0.02) and asthenia-anorexia (p < 0.05). Dermatomyositis and polymyositis subgroups had slightly different significant prognostic factors for death: old age, cancer, pulmonary interstitial fibrosis and asthenia-anorexia for dermatomyositis; old age, failure to improve muscle strength in response to treatment after one month, and the absence of myalgia as presenting symptom for polymyositis. At the end of the follow-up, 33/39 surviving patients (84.6%) had no or insignificant muscular disability, whereas 3 children were bedridden due to generalized calcinosis.

CONCLUSIONS

High mortality occurred in the first year, and the survival rate decreased continually up to 9 years. The main prognostic factor for death is old age, but dermatomyositis and polymyositis must be considered separately. General features (pulmonary fibrosis, cancer, asthenia-anorexia) are involved in dermatomyositis, whereas muscular symptoms are the most significant in polymyositis. The long-term functional prognosis was fairly good, except for generalized calcinosis, which tended to occur in childhood dermatomyositis.

Polymyositis, arthritis, and proteinuria in a patient with adult celiac disease

A 37-year-old woman developed polymyositis and arthritis concomitantly with proteinuria and watery diarrhea. Repeated duodenal biopsies and serological evaluation established the diagnosis of adult celiac disease. Treatment with gluten-free diet resolved all clinical and laboratory abnormalities. We believe that this is the first report of adult celiac disease presenting as a multisystem disease involving kidneys, joint, and muscles.

Update on the use of intravenous immune globulin in the treatment of patients with inflammatory muscle disease

The inflammatory myopathies consist of three distinct groups: dermatomyositis, polymyositis, and inclusion body myositis. Dermatomyositis is distinguished by its characteristic rash, while polymyositis is a diagnosis of exclusion. Inclusion body myositis is characterized by early involvement of distal muscle groups and the quadriceps. Definitive diagnosis is made by muscle biopsy, which demonstrates histological features characteristic for each disorder. Immune mechanisms play a role in the pathogenesis of the inflammatory myopathies. A complement-mediated microangiopathy is seen in dermatomyositis, while there is evidence for a T cell-mediated process in polymyositis and inclusion body myositis. Treatment with prednisone is helpful to a majority of patients for a period of time. Immunosuppressive drugs have met with limited success. We describe a group of patients with dermatomyositis, resistant to available therapies, whose muscle strength, skin changes, and muscle biopsies improved significantly during treatment with intravenous immune globulin. The treatment of polymyositis and inclusion body myositis with intravenous immune globulin is currently under study.

[Cardiac involvement in polymyositis--dermatomyositis associated with Sjogren's syndrome]

A 41 years old woman with polymyositis-dermatomyositis with cardiac involvement is presented. The patient evolved with congestive heart failure, the electrocardiogram showed a left anterior hemiblock, lack of progression of R waves from V1 to V4 and unspecific ST and T alterations. Echocardiogram and cardiac catheterization showed global ventricular disfunction and pulmonary hypertension. An endomyocardial biopsy performed at the apex of the right ventricle showed mononuclear inflammatory infiltration, myocardial fiber degeneration and fibrosis. Initially, the patient responded well to diuretic, vasodilator and steroid therapy. Posteriorly she developed an atrial flutter that required electrical cardioversion and later died suddenly during the course of an acute pneumonia.

Treatment of polymyositis and dermatomyositis

Polymyositis and dermatomyositis are serious inflammatory muscle disorders which may present life-threatening complications. It is important to recognise and treat the condition in the early stages of the disease. Corticosteroids remain the mainstay of treatment, and their resistance and other forms of immunotherapy are discussed.

The spectrum of myositis and rhabdomyolysis associated with bacterial infection

OBJECTIVE

(1) To describe the clinical and radiographic features of 6 patients with myositis or rhabdomyolysis associated with bacterial infection. (2) To analyze the role of computed tomography (CT) in myositis associated with bacterial infection.

METHODS

Review of cases treated by the authors with literature review.

RESULTS

Two patients had classical pyomyositis with Staphylococcus aureus as the etiologic agent. One patient had pyomyositis with Enterobacter cloacae (the first reported to our knowledge), 2 had myositis/fasciitis (one due to Clostridium perfringens and one due to S. aureus), and one had fatal toxic rhabdomyolysis in association with C. perfringens bacteremia without evidence of gas gangrene. No patient had a completely normal CT scan of affected muscles, but CT scans in 3 patients failed to show abscesses that were subsequently discovered at surgery, while in another patient CT scanning falsely suggested a large abscess that was not present at surgery.

CONCLUSION

Infection associated muscle involvement represents a spectrum of clinical manifestations that include pyomyositis, myonecrosis, fasciitis/myositis, and toxic rhabdomyolysis. Diagnosis may be delayed by the often mild clinical presentation. CT scanning alone may be unreliable in distinguishing muscle abscess from swollen muscle unless combined with CT guided needle biopsy.

Intravenous gamma globulin as first line therapy in polymyositis and dermatomyositis: an open study in 11 adult patients

OBJECTIVE

Polymyositis (PM) and dermatomyositis (DM) are inflammatory muscle diseases of presumed autoimmune origin. Many possible interventions are available to treat these patients: corticosteroids, immunosuppressive drugs, plasmapheresis, and total body irradiation. But these therapies are not always effective and may be responsible for certain serious side effects. Polyvalent intravenous immunoglobulin (IVIG) has been tried with success in inflammatory myopathies after failure of traditional treatment. An attempt was made to evaluate the efficacy of IVIG as first line therapy in patients with PM or DM.

METHODS

Eleven Caucasian patients [6 women, 5 men, mean age 55.6 (SD 10.1) years], with active recent inflammatory myopathy, were treated by high doses of IVIG as first choice. The average duration of inflammatory myopathy before IVIG was 9.6 months (SD 10.2 months, with a range of 1 month to 3 years). Five patients had PM and 6 had DM. None had myositis associated with connective tissue disease. Two patients had a history of malignant disease: 1 lymphoma and 1 breast tumor with relapse of the malignancy during the study. One patient had a probable lung carcinoma and in another patient, ovarian carcinoma was diagnosed a few months after the onset of IVIG. We used preparations of polyvalent human i.v. gamma globulins with intact IgG. All patients received 1 g/kg daily for 2 days each month. The mean course of treatment was 4 months.

RESULTS

Clinical assessment, evaluated by proximal muscle power and biochemical tests, was carried out before each treatment period. Significant clinical improvement was noted in only 3 of the 11 patients (one with acute coxsackie virus B infection, and one with possible drug induced myopathy). Mean muscle power estimated for the 11 patients before and after IVIG therapy was not significantly improved. Eight patients showed significant biochemical improvement (more than 50%). Mean CK levels for the 11 patients showed a statistically significant decrease during IVIG therapy (p < 0.01). Minor IVIG side effects were noted in one patient.

CONCLUSION

IVIG therapy seems effective rarely as first therapy in patients with inflammatory myopathy but may be considered especially in viral or drug induced myopathy. IVIG therapy as the first treatment may also be tried in patients with contraindication for steroids, and in mild myopathy, especially in the elderly, to avoid steroid induced side effects.

Regression of Kaposi's sarcoma after intravenous immunoglobulin treatment for polymyositis

The authors report on the case of a patient with polymyositis who was given immunosuppressive therapy and then developed Kaposi's sarcoma. Subsequently, the polymyositis was treated with high dose intravenous immunoglobulin, and the Kaposi's sarcoma regressed abruptly. The association between these two diseases and the beneficial effect of intravenous immunoglobulin on Kaposi's sarcoma are discussed.

Immunomodulation during treatment of polymyositis with plasmapheresis and immunosuppressive drugs

Immunologic studies were carried out in a patient with polymyositis (PM), who showed increasing muscle strength and decreasing serum creatine phosphokinase levels during 20 weeks of treatment with plasmapheresis in conjunction with prednisone and cyclophosphamide. After an initial rise, serum IgG declined with treatment. Natural killer (NK) lymphocytes were reduced by 74%, B cells by 95%, and T cells by 38%. Spontaneous proliferation of peripheral blood mononuclear cells increased dramatically. Within the CD4+ T cell subset there was increasing maturation as shown by a rise in percent mature (CD29+) cells and reciprocal decline of immature (CD45RA+) cells. At the same time CD4+ T cells became increasingly activated as shown by HLA-DR expression. The percentage of CD8+ T cells increased strongly with treatment, and they showed increased activation and expression of the cytotoxic CD29+ and CD11b- phenotypes. CD8+ T cells exhibiting CD45RA or CD11b+ suppressor phenotypes were overall unchanged; however, on follow-up a proportion of CD8+ cells expressed the activated suppressor effector (CD11b-CD28-) phenotype. In addition to control of PM by the possible deletion of activated autoreactive B and T lymphocyte clones with cyclophosphamide, the activation and maturation of CD4+ T cells during treatment may have downregulated the autoreactive disease process, either through direct antiidiotypic suppression or by induction of the observed increase in cytotoxic and suppressor CD8+ T cells.

Isometric exercise increases strength and does not produce sustained creatinine phosphokinase increases in a patient with polymyositis

A patient with active stable idiopathic polymyositis received a 4-week supervised right quadriceps and biceps isometric strengthening program. He demonstrated a significant increase in isometric peak torque without a sustained rise in creatinine phosphokinase (CPK). A significant decrease in postexercise CPK occurred at the end of the exercise program. We conclude a randomized clinical trial using a nonexercised patient group vs an exercised patient group may be useful.

Polymyositis with plasma cell infiltrate in essential mixed cryoglobulinaemia

A patient with essential cryoglobulinaemia who presented with polymyositis is described. Muscle biopsy showed intense plasma cell infiltration of muscle. Plasmapheresis produced a rapid resolution of the cutaneous manifestations of the disease, but little improvement in muscle strength. Oral steroids resulted in moderate improvement in muscle strength. There have been no previously reported cases of polymyositis in association with essential cryoglobulinaemia.

Multifactorial study of inflammatory myopathies. Report of 29 cases

We made a comparative clinical, immunopathological and therapeutic evaluation in 17 patients with polymyositis (PM) and 12 patients with dermatomyositis (DM), followed up at our Neuromuscular Center. DM can be distinguished by its clinical appearance and pathological changes. Current evidence suggests that it results from vasculopathy. For studying these inflammatory myopathies we used multifactorial diagnostic criteria, evaluating the therapeutic response by means of a composite clinical and functional score in a longitudinal study. In muscle biopsy specimens we characterized with monoclonal antibodies T lymphocyte subpopulations (CD4, CD8), macrophages, IgG, IgM, C1q, C3, C4 complement fractions, MHC-I, MHC-II. In PM the cell-mediated immunity was more pronounced and in some cases both MHC-I and MHC-II molecules were found on the surface or within muscle fibers. Our patients were treated with steroids; in resistant cases azathioprine, cyclophosphamide, plasmapheresis, high-dose intravenous immunoglobulins (ivIgG) and total body irradiation were added to the therapeutic schedule.

[Polymyositis: disease course and therapy with intravenously administered immunoglobulins]

Corticosteroids and immunosuppressive agents are standard treatment for polymyositis (PM) and dermatomyositis (DM) respectively. Recent reports have emphasized a potentially successful regimen with intravenous immune gammaglobulins (IVIG). The short term success of this treatment in a personally observed case is described. IVIG treatment resulted in normalization of the serum concentrations of the muscle enzymes after continued inflammatory activity under treatment with azathioprine, cyclophosphamide and methotrexate in combination with corticosteroids. The improvement of PM by IVIG was further documented by an increase in muscle strength of up to 367% of the initial value and a regression of the myositic changes in the muscles of the thighs as evidenced by magnetic resonance imaging (MRI). The therapeutic response was paralleled by reversal of peripheral lymphopenia. Experience with IVIG treatment in PM/DM is reviewed and the potential role of this regimen in the management of PM/DM is discussed.