The presence of a systemic disease with vasculitic manifestations preceded by asthma, allergic symptoms, and eosinophilia is suggestive of CSS. Eosinophil counts are typically greater than 1.500/mm3. ANCAs may or may not be helpful for the diagnosis, since they are only present in 40% to 50% of patients (34). A positive ANCA is helpful, but a negative test does not rule out CSS. When present, ANCA is usually a perinuclear ("P") pattern on immunofluorescence and the antibodies are reactive to MPO. Occasionally, the antibody specificity may be to PR3, and the IIF pattern is cytoplasmic (C-ANCA). Chest imaging studies may show typical findings of bilateral patchy migratory interstitial or alveolar infiltrates. Pulmonary nodules are uncommon and cavities are very rare, the latter suggesting WG or secondary infection.
The differential diagnosis includes granulomatous diseases that may present with eosinophilia such as eosinophilic pneumonia, allergic bronchopulmonary aspergillosis, WG, parasitic and fungal infections, malignancy, and eosinophilic granuloma. When there is uncertainty about the diagnosis, pathologic confirmation should be pursued.
Was this article helpful?
If you suffer with asthma, you will no doubt be familiar with the uncomfortable sensations as your bronchial tubes begin to narrow and your muscles around them start to tighten. A sticky mucus known as phlegm begins to produce and increase within your bronchial tubes and you begin to wheeze, cough and struggle to breathe.