A 65-year old Moroccan woman was hospitalized for polyarthralgia and frontal headache. She had a past medical history of asthma for 10 years and was operated for hydatid cyst of the liver in 1998. She has no history of tuberculosis, no chronic abdominal pain.
On physical examination, blood pressure was 140/70 mmHg and the heart rate 70/min. She has no fever and the peripheral pulses were all present. We noted an infiltrated purpura in the lower extremities and a wheezing in the pulmonary fields. She has areflexia and sensory involvement in the lower limbs.
Hemoglobin was at 7.5 g/dl, MCV 80 fl, Reticulocyte count at 47.10X3/mm3, platelet count at 730 000/ microL (Normal 150-450 000) and white blood cell count 10000/ microL with neutrophil 4300, lymphocytes at 3600/ microL and eosinophil 1150/ microL (normal 100-500/ microL). Erythrocyt sedimentation rate was 130 mm first hour, C-reactive protein 38 mg/l (range < 6 mg/l), fibrinogen 6 g/l (2-4 g/l) and serum protein electrophoresis showed a polyclonal IgG 24 g/l (range 9-13 g/l) with normal immunofixation. There was renal failure with urea 3 mmol/l (normal 3 - 8.5), creatinemia 160 micromol/l (normal 45 -100) and creatinine clearance at 30 ml/min (Cockcroft formula).
Urinalysis showed a microscopic haematuria at 20 000 cell/mm3 and proteinuria at 2.5g/24Hr. Cryoglobulinemia was negative, p-ANCA were present. Electromyography showed an axonal polyneuropathy of the 4 limbs. Skin biopsy revealed leukocytoclastic vasculitis with extra-vascular eosinophil. Thorax CT showed pulmonary infiltrates changes. Brain CT, temporal artery biopsy and ocular examination were all normal. Renal biopsy did not reveal vasculitis or inflammatory process, but an important type AA amyloid deposit. Salivary biopsy also showed AA amyloid deposit. She has no Familial Mediterranean fever, no history of tuberculosis or other chronic infections.
The diagnosis of Churg Strauss associated with AA amyloidosis was established with five criteria of the American College of Rheumatology (ACR).
Steroids were administered at a pulse of methyprednisolone 1g/day for 3 days followed by oral prednisone at 1 mg/kg/day for 4 weeks and progressively tapered. The patient was also treated with captopril. The clinical and biological response was obtained with disappearance of pain; eosinophil count decrease to 300/microL and negativity of proteinuria. At 26 months follow-up proteinuria remained negative.