[Diffuse bilateral pulmonary infiltrates with multiorgan involvement]

This article reports the management of a female patient who initially presented at onset with severe pneumonia and profound anaemia. The patient was critically ill and deteriorated rapidly, developing acute respiratory failure that necessitated endotracheal intubation. After stabilization of vital signs, a definitive diagnosis was established through a multimodal workup including bronchoalveolar lavage, bone marrow aspiration, and renal biopsy, among other modalities. The findings ultimately confirmed anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis with pulmonary and renal involvement; in addition, the potential association between Tropheryma whipplei and pneumonia was discussed. With active etiology-targeted treatment, the patient's symptoms improved rapidly, and the pulmonary inflammation eventually resolved completely.