A 40-year-old lady presents with dyspnoea. She describes a gradual onset of shortness of breath on exercise over several months. She has a past medical history of wheeze as an infant. She has recently commenced a intranasal steroid spray for rhinitis. She is a non-smoker.
On examination she has oxygen saturations of 91% on air. She has blood stained crusting around her anterior nares. On auscultation her chest has bilateral reduced air entry and coarse crepitations on both lung bases. Her temperature is 37.8 degrees centrigrade.
Hb 13.2 g/dL
WCC 10.3 *10^9/l
Neutrophil 7.8 *10^9/l
Eosinophil 0.07 *10^9/l
Sodium 135 mmol/l
Potassium 4.5 mmol/l
Creatinine 113 µmol/l
Urea 5.4 mmol/l
CRP 230 mg/L
Chest X - ray Bilateral basal consolidation
Urine microscopy Culture negative
RBC +++ WCC +
c-ANCA Positive
p-ANCA Positive
Anti-GBM Negative
What is the most likely diagnosis?
Pneumonia
Churg-Strauss Syndrome
Microscopic polyangiitis
Granulomatosis with polyangiitis
Goodpastures disease
Definitive diagnosis of vasculitis will require biopsy. However, granulomatosis with polyangiitisis the most likely as the presentation includes sinus disease, lung disease with likely renal involvement. Both ANCA tests can be positive but it is most associated with c-ANCA.
This patient had wheeze as a child, which is very common. Churg-Strauss is more associated with a progressive presentation of asthma, which may present later in life. The patient also does not have eosinophilia which is associated with this diagnosis.
Goodpasture’s is a possibility but less likely with a negative anti-GBM. Pnemonia is less likely with such a prolonged presentation.
Microscopic polyangiitis can present very similar to granulomatosis with polyangiitis but is more associated with renal involvement, which is mild in this case. It is less associated with ENT disease.