Acute renal failure in a patient affected with Churg and Strauss syndrome

Renal involvement in Churg-Strauss syndrome

BACKGROUND

Churg-Strauss syndrome (CSS) is a rare disorder characterized by asthma, eosinophilia, and systemic vasculitis. Renal involvement is not regarded as a prominent feature, and its prevalence and severity vary widely in published reports that usually refer to small series of selected patients.

METHODS

We examined the prevalence, clinicopathologic features, and prognosis of renal disease in 116 patients with CSS.

RESULTS

There were 48 men and 68 women with a mean age of 51.9 years (range, 18 to 86 years). Signs of renal abnormalities were present in 31 patients (26.7%). Rapidly progressive renal insufficiency was documented in 16 patients (13.8%); urinary abnormalities, 14 patients (12.1%); and chronic renal impairment, 1 patient. There were 3 additional cases of obstructive uropathy. Sixteen patients underwent renal biopsy, which showed necrotizing crescentic glomerulonephritis in 11 patients. Other diagnoses were eosinophilic interstitial nephritis, mesangial glomerulonephritis, and focal sclerosis. Antineutrophil cytoplasmic antibody (ANCA) was positive in 21 of 28 patients (75.0%) with nephropathy versus 19 of 74 patients without (25.7%; P < 0.001). In particular, all patients with necrotizing crescentic glomerulonephritis were ANCA positive. After a median follow-up of 4.5 years, 10 patients died (5 patients with nephropathy) and 7 patients developed mild chronic renal insufficiency. Five-year mortality rates were 11.7% (95% confidence interval, 3.9 to 33.3) in patients with nephropathy and 2.7% (95% confidence interval, 0.7 to 10.7) in those without (P = 0.10).

CONCLUSION

Renal abnormalities are present in about one quarter of patients with CSS. The prevailing picture is ANCA-associated necrotizing crescentic glomerulonephritis; however, other forms of nephropathy also may occur. Outcome and long-term follow-up usually are good.

Prevalence and clinical significance of antineutrophil cytoplasmic antibodies in Churg-Strauss syndrome

OBJECTIVE

Churg-Strauss syndrome (CSS) is classified among the so-called antineutrophil cytoplasmic antibody-associated systemic vasculitides (AASVs) because of its clinicopathologic features that overlap with the other AASVs. However, while antineutrophil cytoplasmic antibodies (ANCAs) are consistently found in 75-95% of patients with Wegener's granulomatosis or microscopic polyangiitis, their prevalence in CSS varies widely and their clinical significance remains uncertain. We undertook this study to examine the prevalence and antigen specificity of ANCAs in a large cohort of patients with CSS. Moreover, we evaluated the relationship between ANCA positivity and clinicopathologic features.

METHODS

Immunofluorescence and enzyme-linked immunosorbent assay were used to determine the presence or absence of ANCAs in 93 consecutive patients at the time of diagnosis. The main clinical and pathologic data, obtained by retrospective analysis, were correlated with ANCA status.

RESULTS

ANCAs were present by immunofluorescence in 35 of 93 patients (37.6%). A perinuclear ANCA (pANCA) pattern was found in 26 of 35 patients (74.3%), with specificity for myeloperoxidase (MPO) in 24 patients, while a cytoplasmic ANCA pattern, with specificity for proteinase 3, was found in 3 of 35 patients (8.6%). Atypical patterns were found in 6 of 30 patients with anti-MPO antibodies (20.0%). ANCA positivity was associated with higher prevalences of renal disease (51.4% versus 12.1%; P < 0.001) and pulmonary hemorrhage (20.0% versus 0.0%; P = 0.001) and, to a lesser extent, with other organ system manifestations (purpura and mononeuritis multiplex), but with lower frequencies of lung disease (34.3% versus 60.3%; P = 0.019) and heart disease (5.7% versus 22.4%; P = 0.042).

CONCLUSION

ANCAs are present in approximately 40% of patients with CSS. A pANCA pattern with specificity for MPO is found in most ANCA-positive patients. ANCA positivity is mainly associated with glomerular and alveolar capillaritis.

Vasculitides with predominantly renal involvement: influence of age on the mode of presentation

Vasculitis with predominant renal involvement are increasingly observed in elderly patients. It predominantly involves patients with microscopic polyangiitis, Wegener's granulomatosis, renal limited vasculitis and, in a smaller proportion, Churg Strauss syndrome. The elderly patients present very few obvious symptoms or signs of vasculitis such as hemoptysis and pulmonary infiltrates, and they are often submitted to: 1/renal biopsy when renal failure is already advanced; 2/ have more severe renal disease than do young and middle-aged patients (81% of acute and/or rapidly progressive renal failure versus 62%, and 30% of oliguria versus 6%); and 3/ a worse prognosis compared with younger individuals (probability of survival at 3 months, 1 year and 5 years of 93%, 93% and 92% in patients under 65, versus 67%, 62% and 46% in the elderly). Management of all patients with vasculitis and predominant renal involvement requires a quick diagnosis and immunosuppressive treatment aimed at controlling the disease. Treatment is mantained for 18 to 24 months. Nevertheless, relapses do occur (between 20% to 52%) of all patients with microscopic polyangiitis and Wegener's granulomatosis.

Churg-Strauss syndrome. Clinical study and long-term follow-up of 96 patients

Churg-Strauss syndrome (CSS) is a systemic vasculitis characterized by the presence of asthma, hypereosinophilia, and necrotizing vasculitis with extravascular eosinophil granulomas. In this retrospective study of 96 patients between 1963 and 1995, we analyzed clinical manifestations, identified prognostic factors, and assessed the long-term outcome. CSS was diagnosed when asthma, hypereosinophilia > 1,500/mm3 or > 10%, and clinical manifestations consistent with systemic vasculitis, with or without histologic evidence, were present. Asthma was the most frequently observed manifestation at presentation, with mononeuritis multiplex the second. Other common manifestations were weight loss, fever, myalgia, skin involvement, paranasal sinusitis, arthralgia, pulmonary infiltrate, and gastrointestinal involvement. Mean eosinophilia at presentation was 7.193 +/- 6.706/mm3; ANCA, present in 20 of 42 (47.6%) patients, predominantly gave the perinuclear labeling pattern. All the patients were treated with corticosteroids alone or in combination with cyclophosphamide or plasma exchanges. Clinical remission was obtained in 91.5%; 22 (25.6%) patients relapsed. Twenty-three patients died during follow-up: 11 of these deaths were directly due to vasculitis. The presence of severe gastrointestinal tract or myocardial involvement was significantly associated with a poor clinical outcome. The long-term prognosis of CSS is good and does not differ from that of polyarteritis nodosa, although most patients need low doses of oral corticosteroids for persistent asthma, even many years after clinical recovery from vasculitis.

Vasculitis in childhood

Systemic vasculitic syndromes are rare in childhood. Vasculitis is the predominant feature of a large number of different clinical entities that are linked by the presence of inflammatory changes in the blood vessels. The nature of these diseases and their relationship to each other remain unclear. The clinical presentation associated with the size of the affected vessels and epidemiological data are very helpful for the diagnosis of those diseases. Recent advances are beginning to shed some light on the etiology and pathogenetic mechanisms involved in the various vasculitides. There is good evidence to support roles for circulating immune complexes, cell-mediated immunity, anti-neutrophil cytoplasmic antibodies and anti-endothelial cell antibodies in the pathogenesis. Renal involvement in vasculitis in children is commonly seen in Henoch-Schönlein purpura, microscopic polyarteritis, Wegener's granulomatosis, Churg-Strauss syndrome and polyarteritis nodosa. However, kidney disease can also be part of the clinical picture of Kawasaki disease and Takayasu arteritis. Recently, with the institution of early and aggressive immunosuppressive treatment of severe cases, significant improvement in the long-term survival of patients has been achieved. This review article addresses the pathological and clinical features (particularly renal involvement), therapeutic intervention and prognosis of the above-mentioned diseases.