PMC7656191_01
Clinical progress. This figure highlights significant events, antimicrobial therapy administered, infective markers, and wound and blood cultures sent during this admission. *All positive blood cultures grew S. apiospermum. PO, oral; IV, intravenous; VT, ventricular tachycardia; VF, ventricular fibrillation; ICD, implantable cardiac device; AF, atrial fibrillation; DCCV, direct current cardioversion; CRRT, continuous renal replacement therapy; LVAD, left ventricular assist device; WBC, white blood cell; CRP, C-reactive protein.
acmi-2-148-g001.jpg
PMC7656191_01_acmi-2-148-g001.jpg
F1
At presentation, he was afebrile, with no localizing signs of infection; his driveline was well healed, and apart from a slight increase in C-reactive protein (CRP) at 32.1 mg l-1, his other infective markers were within normal limits, as shown in Fig. 1. This was associated with progressive leukocytosis and rising CRP and procalcitonin levels, despite cefepime and vancomycin therapy (Fig. 1). Despite broad-spectrum antibiotics, there was progressive clinical deterioration, as detailed chronologically in Fig. 1. Multiple blood cultures were collected in BD BACTEC Plus Aerobic/F ('Aerobic'), BD BACTEC Plus Anaerobic/F ('Anaerobic') and BD BACTEC Myco/F Lytic ('Fungal') bottles (BD Diagnostic Systems) (Fig. 1). In total, five blood culture bottles flagged positive, indicating growth detected by the blood culturing instrument, from specimens collected on hospital days 7, 9 and 11 (Fig. 1).
S. apiospermum. (a) Upon detection of growth in a blood culture bottle, Gram staining of broth from the positive blood culture bottles was performed. A representative Gram stain of broth from a positive blood culture at the point of growth detection, after 4 days of incubation in the BACTEC FX blood culturing instrument, is shown here. (b) Same as (a), but at higher magnification. Septate hyphae and conidia with truncated bases are observed (arrows). (c) Broth from the positive blood culture bottles was inoculated onto potato dextrose agar and incubated at 30  C, obtaining fungal isolates with a house mouse grey morphology. The fungal isolates here were obtained after 5 days of growth. (d) Lactophenol cotton blue staining of the fungal isolate in (c) was performed, showing the characteristic septate hyphae and conidia arrangement of S. apiospermum. The conidia seen here appear to be more prolific than in (a) due to the different media used.
acmi-2-148-g002.jpg
PMC7656191_01_acmi-2-148-g002.jpg
F2
Macroscopic and microscopic findings are presented in Fig. 2.