A challenging case of pulmonary fusariosis superimposed on coronary artery bypass surgery complications in an uncontrolled diabetic patient

A 68-year-old man with poorly controlled type 2 diabetes mellitus, recent non-ST-elevation myocardial infarction (NSTEMI), and coronary artery bypass grafting was readmitted for purulent mediastinal wound discharge. Methicillin-sensitive Staphylococcus aureus grew from wound cultures and intravenous cefazolin was initiated. During hospitalization the patient sustained an acute ST-segment-elevation myocardial infarction (STEMI) requiring percutaneous coronary intervention. Post-procedure imaging revealed left lung collapse from a large pleural effusion on computed tomography (CT) scan, also confirmed through bronchoscopy. The effusion was drained through left chest tube thoracostomy after which the lung re-expanded. Bronchial lavage cultures grew pan-sensitive Pseudomonas aeruginosa, prompting intravenous ciprofloxacin. Seven days later, fungal cultures from the same bronchoalveolar lavage yielded colonies of mold which were apricot coloured. Microscopy demonstrated sickle-shaped conidia consistent with Fusarium species. The patient was clinically stable and discharged on oral cephalexin and ciprofloxacin; outpatient voriconazole was added once the mold was identified. At a two-month follow-up he remained asymptomatic with a clean sternotomy wound and clear chest radiograph. This report highlights the importance of pursuing fungal culture in persistent pulmonary or postoperative infections, recognising Fusarium as an emerging pathogen in diabetics and post-cardiac surgery patients, and initiating timely azole therapy despite initial clinical improvement. Keywords: Fusariosis, Pseudomonas aeruginosa, Pleural effusion, postoperative infection, diabetes mellitus, NSTEMI.