The American College of Rheumatology 1990 criteria for the classification of giant cell arteritis

Elevated serum levels of soluble interleukin-2 receptor in patients with Wegener's granulomatosis. Association with disease activity

OBJECTIVE

To investigate whether soluble interleukin-2 receptor (sIL-2R), a marker of T cell activation, could be a useful marker of disease activity in Wegener's granulomatosis (WG).

METHODS

Soluble IL-2R levels were determined by enzyme-linked immunosorbent assay. WG disease activity in 102 patients was assessed according to clinical features and levels of classic antineutrophil cytoplasmic antibody (c-ANCA) and C-reactive protein (CRP).

RESULTS

Soluble IL-2R levels were higher in patients with generalized and active disease than in those with limited and inactive disease. In 25 patients with complete clinical remission, sIL-2R levels were significantly elevated, although levels of CRP and c-ANCA were normal. Eight of these 25 patients had disease relapses within 6 months. Levels of sIL-2R were significantly higher in patients who had relapses than in those who did not. Patients with clinically active WG but low c-ANCA or CRP levels had elevated levels of sIL-2R.

CONCLUSION

Levels of sIL-2R correlate with disease activity in patients with WG, and may indicate imminent relapse.

Anti-myeloperoxidase autoantibodies in patients with necrotizing glomerular and alveolar capillaritis

We conducted a prospective study of 651 Mediterranean patients from Catalonia (Spain) with well-defined forms of systemic vasculitis, connective tissue diseases, and renal and pulmonary disorders to determine the prevalence and clinical value of antineutrophil cytoplasmic autoantibodies (ANCA) with myeloperoxidase (MPO) specificity (MPO-ANCA). ANCA were first tested by indirect immunofluorescence on ethanol-fixed neutrophils. When a positive result was obtained, then MPO-ANCA were identified by performing the immunofluorescence assay again on neutrophils from a voluntary donor known to have a complete and selective deficiency of MPO. This disorder was detected by automated flow cytochemistry with the Technicon system and was further verified by cytochemical and biochemical studies. We detected MPO-ANCA in 61 of 70 (87%) patients with a perinuclear pattern (p-ANCA), but in none of 25 with a cytoplasmic pattern (c-ANCA). These results were corroborated by enzyme-linked immunosorbent assay (ELISA) using human purified MPO as a substrate. On immunofluorescence microscopy, all patients with MPO-ANCA were found to have a typical and restrictive immunostaining pattern. In our study, while c-ANCA were mainly found in patients with biopsy-proven Wegener's granulomatosis, MPO-ANCA identified those with idiopathic and polyarteritis nodosa-associated necrotizing and crescentic glomerulonephritis. In addition, pulmonary hemorrhage with necrotizing alveolar capillaritis as the main morphologic substrate occurred frequently among patients with MPO-ANCA, including three affected by polyarteritis nodosa and three who had pulmonary hemorrhage as the only clinical finding. On the other hand, these antibodies could be also detected in 30% of patients with a proven diagnosis of anti-glomerular basement membrane (GBM) disease.(ABSTRACT TRUNCATED AT 250 WORDS)

Temporal arteritis with low erythrocyte sedimentation rate: a review of five cases

We compared 5 patients who had biopsy-proven temporal arteritis and erythrocyte sedimentation rates (ESR) less than 50 mm/hour with 25 patients who had temporal arteritis and high ESR and with 10 patients who had negative temporal artery biopsy results and low ESR. Patients with low-ESR temporal arteritis were similar to the other groups, except that they had a higher mean hemoglobin level than the high-ESR group and a significant increase in the percentage of patients (4 of 5) who had a previous diagnosis of polymyalgia rheumatica or had received steroid therapy compared with either of the other groups. The latter finding suggests that even low-dose steroid therapy can lower the ESR in patients with temporal arteritis. We conclude that the ESR is low in only a small percentage of patients with temporal arteritis, and that most of these patients have a history of polymyalgia rheumatica or steroid therapy.

[Temporal artery syndrome in amyloidosis AL associated with myeloma]

The authors report a case of amyloidosis AL associated with light lambda chain myeloma, mimicking giant cell temporal arteritis. The normality of inflammatory proteins, the primary resistance to corcicosteroids and the results of temporal artery biopsy (amyloid deposits without giant cell granuloma) excluded a diagnosis of giant cell arteritis associated with amyloidosis. The most probable mechanism was infiltration of branches of the external carotid artery. In patients with temporal arteritis, amyloidosis must be suspected and sought, particularly in case of monoclonal dysglobulinaemia or manifestations that are not typical of giant cell temporal arteritis. The prognosis of vascular amyloidosis seems to be more favourable than that of the classical visceral types. The primary amyloidosis of these patients must be treated with melphalan combined with prednisone and colchicine.