A 34-year-old female presents with shortness of breath.
She has been treated for asthma by her GP with an inhaled steroid, but the GP has documented an eosinophilia of 1.1x109/L (14%) (normal <0.1x10). Her creatinine has also been found to be 347µmol/l (60-110).
Which of the following would most support a diagnosis of Churg-Strauss syndrome?
Extravascular eosinophils on vascular biopsy
Fixed pulmonary infiltrates on chest radiographs
Peak flow <300 L/min
Peripheral alveolar filling infiltrate predominantly in the upper lobes on a chest radiograph
Peripheral ‘stocking’ neuropathy
Explanation:
A diagnosis of Churg-Strauss syndrome requires four of the following features:
asthma
eosinophilia greater than 10%
mononeuropathy or polyneuropathy
paranasal sinus abnormality
non-fixed pulmonary infiltrates visible on chest radiographs, and
biopsy demonstrating extravascular eosinophils.
Peripheral alveolar filling infiltrates predominantly in the upper lobes on a chest radiograph is typical of chronic eosinophilic pneumonia.
A peripheral ‘stocking and glove’ neuropathy is not typical of Churg-Strauss syndrome and is more common in type 2 diabetes.
Peak flow <300 L/min is low, but is non-specific, and in isolation would not be suggestive of a diagnosis of Churg-Strauss syndrome.