Magnetic resonance imaging of skeletal muscle involvement in limb restricted vasculitis

BACKGROUND

Limb restricted polyarteritis nodosa (PAN) and PAN-type diseases such as isolated vasculitis of skeletal muscle are localised vasculitides affecting the skin, muscles, or peripheral nerves, usually of the lower limbs. These diseases often present with non-specific clinical symptoms and normal laboratory values and electromyograms. The usefulness of magnetic resonance imaging (MRI) of skeletal muscle has been poorly investigated to date.

OBJECTIVE

To describe the MRI findings in the legs of three patients with limb restricted vasculitides (two PAN, one isolated vasculitis of the skeletal muscle) with histologically established muscle involvement.

METHODS

MRI was carried out on calf muscles and T(2) weighted images, unenhanced T(1) weighted images, and STIR sequences were obtained.

RESULTS

Muscle damage resulted in oedema-like changes on MRI characterised by hyperintense signals in T(2) weighted and slow tau inversion recovery (STIR) sequences and normal unenhanced T(1) weighted sequences of one or several leg muscles.

CONCLUSIONS

MRI should be considered a useful complementary examination that might facilitate the recognition of limb restricted vasculitides, and possibly indicate the site for muscle biopsy. It could also be useful in monitoring the course of the disease. Future studies should also evaluate MRI for systemic PAN or other systemic vasculitides with muscle involvement.

Efficacy of the anti-TNF-alpha antibody infliximab against refractory systemic vasculitides: an open pilot study on 10 patients

OBJECTIVE

Evidence indicates that tumour necrosis factor (TNF) is a major agent in the pathogenesis of vasculitis. We studied the short-term effect of anti-TNF-alpha antibody in systemic vasculitis patients refractory to steroids and immunosuppressive agents.

METHODS

Ten patients refractory to corticosteroids and at least one immunosuppressant and who had persistently active disease or a new flare were included. Seven had Wegener's granulomatosis, two had rheumatoid arthritis-associated vasculitis and one had cryoglobulinaemia with mean duration of 9.1, 21.5 and 17 yr. They received infliximab (5 mg/kg) on days 1, 14, 42 and then every 8 weeks. Immunosuppressants were stopped between days 0 and 42 for eight patients, while the steroid dose was maintained or lowered. The treatment response was evaluated clinically with the Birmingham Vasculitis Activity Score 2000 (BVAS).

RESULTS

Complete or partial remission was observed in all patients. The mean BVAS at entry was 9.1 (range 4-15) and had declined to 1.9 (range 0-4) by day 42 and 1.3 (range 0-4) at 6 months; BVAS of 0 was recorded for four patients on day 42 and for five at 6 months. The only adverse effect was cutaneous eruption in two patients.

CONCLUSION

Anti-TNF-alpha successfully induced prompt symptomatic responses in patients with systemic vasculitis not responding to conventional treatment. Infliximab was well tolerated during the short-term follow-up.

[Central nervous system and systemic vasculitides]

Central nervous system (CNS) involvement can occur in large, medium, or small-sized vessel vasculitides. It is present in less than 10p. cent of systemic vasculitides. Clinical symptoms are heterogeneous and reflect the various mechanisms involved: vasculitis, blood hypertension, thrombosis and embolism. The symptoms can be present initially, at the time of relapse or occur as a treatment side effect. A primary angiitis of the CNS can also be observed. This granulomatous vasculitis is rare and isolated. Its diagnosis is difficult. The prognosis has improved but the disease remains severe. Diagnosis can be made by histology but is suggested by the association of clinical symptoms and brain imaging. Cognitive modifications, sometimes severe can also be observed but can improve with treatment. Prognosis of CNS manifestations is severe. It counts for one point in the Five Factor Score (FFS) which has been validated in some systemic vasculitides. The death rate is 12p. cent when the score is 0 and 50 percent for 2 points. Patients should be treated with a combination of steroids and cyclophosphamide which improves CNS vasculitis outcome.

Churg-Strauss syndrome in two patients receiving montelukast

OBJECTIVE

Churg-Strauss syndrome (CSS) has been described in association with the treatment of asthmatic patients with leukotriene receptor antagonist. The main mechanism proposed to explain this condition is the unmasking of CSS after the leukotriene receptor antagonist has allowed corticosteroid tapering. Other hypotheses might be proposed.

METHODS

We describe two patients who developed CSS after starting treatment with montelukast, a new antileukotriene drug.

RESULTS

Both patients presented with CSS after 4-5 months of treatment with montelukast. Neither patient received long-term systemic steroids for asthma, but both were on inhaled steroids. One patient had a myocardial involvement and experienced a stroke. Our two patients were treated with systemic steroids and cyclophosphamide.

CONCLUSIONS

CSS does not appear to relate to steroid tapering in our patients. The other hypotheses are a coincidence or a direct adverse effect of the antileukotriene. Long-term data on these drugs are lacking and leukotriene's role in vasculitis remains to be elucidated.

Characteristics and outcome of 49 patients with symptomatic cryoglobulinaemia

OBJECTIVE

To describe a population of patients with symptomatic cryoglobulinaemia, comparing manifestations and outcome as a function of hepatitis C virus (HCV) status.

PATIENTS AND METHODS

A retrospective study on 179 patients who tested positive for cryoglobulins, seen between 1978 and 1998 in an internal medicine department.

RESULTS

Among 179 cryoglobulin-positive patients, only 49 (18 men, 31 women; mean age 59.96+/-12 yr) had clinical manifestations attributable to cryoglobulinaemia. Thirty-three had HCV infection, 20 had systemic autoimmune diseases, two had haematological diseases, one had human immunodeficiency virus and HCV co-infection, one had HCV and HBV co-infection and six had essential mixed cryoglobulinaemia. The clinical manifestations and cryoglobulin levels in HCV(+) and HCV(-) patients did not differ significantly. Only arthralgias and elevated transaminases were significantly more frequent in HCV(+) patients (P<0.02 and <0.05, respectively). Five-year survival rates were comparable for HCV(+) and HCV(-) patients. Eight patients died (six HCV(+), two HCV(-)), with a median time between diagnosis and death of 38.7 months.

CONCLUSION

Clinical manifestations of cryoglobulinaemia, except arthralgias, were comparable for HCV(+) and HCV(-) patients. When systemic manifestations are present, the prognosis is poor despite intensive or prolonged therapy.