A 52-yr-old Hispanic man is found to have antineutrophil cytoplasmic autoantibody (ANCA)– associated microscopic polyangiitis with both renal and pulmonary involvement. He is treated with oral prednisone and cyclophosphamide. The prednisone is tapered and discontinued after 4 mo, and azathioprine is substituted for cyclophosphamide at 6 mo. His initial serum creatinine was 2.1 mg/dl, and it decreased to a nadir of 1.7 mg/dl after 6 mo of therapy. He is now seen for a follow-up examination 1 yr after the initial diagnosis. He is asymptomatic. Therapy consists of 100 mg of azathioprine daily and 10 mg of enalapril daily. His BP is 130/80 mmHg. Physical examination is normal. Urinalysis reveals 1 to 2 erythrocytes and 1 white blood cell per highpower field, occasional granular casts, and 2 proteinuria. The serum creatinine is now 1.8 mg/dl. The erythrocyte sedimentation rate is 20 mm/h (Westergren method). An ANCA test performed 1 wk ago was positive in a titer of 1:128. Previous values have been intermittently positive at low titer. NEXT STEP IN MANAGEMENT

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hematuria quiz 2

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CT  of abdomen with iv contrast was done . how will you narrow your differential diagnosis ?What is most likely cause for patient hematuria

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This patient has ANCA positive microscopic polyangiitis and is in a clinical remission, with residual proteinuria and renal impairment. The remission has been induced with sequential cyclophosphamide and azathioprine therapy and the only outward manifestation of possible continued “activity” of disease is a positive ANCA serology. While persistence of positive ANCA serology, despite clinical remission may herald a clinical relapse in some patients many exceptions to this finding have been described. Most experts agree that it is better to carefully follow patients with clinically quiescent disease who are serologically positive and to reinstitute therapy at the first sign of a clinical relapse, rather than to expose patients to unnecessary and potentially toxic therapy, based solely on a serologic finding, which may represent a “false positive” with respect to “active” disease. Nevertheless, patients who are serologically “active” may be at increased risk of relapse, especially when they develop an intercurrent infection. Prophylactic trimethoprim-sulfamethoxazole may reduce the likelihood of a recrudescence of pulmonary angiitis, but seems to be less effective in preventing renal relapses. Mycophenolate mofetil may be effective as maintenance therapy in this situation, but prospective studies have not yet been conducted to test this point.

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RHEUMATOLOGYVasculitis

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