A 24 year old man presents with a non-productive cough and worsening exertional dyspnea for 1 month, associated with intermittent chills and night sweats.

He was treated with Roxithromycin + Amoxicillin for 2 weeks, with no response.

His basic investigations are significant for an Hb of 6.0 g/dL with normal leukocyte and platelet counts, and a serum creatinine of 1.6 mg/dL, with an eGFR of 30 ml/min/1.73m2.

A CXR shows pulmonary infiltrates in the lower regions of both lungs; a urinalysis shows microscopic hematuria with erythrocyte casts.

Select Relevant Investigations
Atypical Pneumonia Screen


Serology is negative for Legionella, Chlamydia, Mycoplasma and Rickettsia.
Renal Biopsy


The renal biopsy shows a diffuse necrotizing glomerulonephritis with crescent formation in ~50% of glomeruli, and smooth linear staining of the glomerular basement membranes.
Bronchoalveolar Lavage


Sequential bronchoalveolar lavage aliquots reveal the presence of diffuse alveolar hemorrhage.
Autoimmune Screen


ANCA: negative for C and P-ANCA
ANA titre: undetectable
Anti-GBM Abs: present

Select Relevant Management
Antituberculous therapy