PMC7360421_01
(A) Fluoroscopy of mechanical prosthetic mitral valve showed one fixed leaflet. (B) Mechanical prosthetic mitral valve from surgery showed large thrombus and pannus. (C) Chest X-ray demonstrated pulmonary edema.
IDR-13-2245-g0001.jpg
PMC7360421_01_IDR-13-2245-g0001.jpg
F0001
Fluoroscopy evaluation showed that the motion of one leaflet of the prosthetic MV was fixed, while the other had severely restricted motion (Figure 1A). Gross pathology showed a severe thick pannus formation with large thrombus on the prosthetic MV that caused malfunction (Figure 1B). On April 13, 2019, about 2 months after discharge, she went back to the emergency department with acute pulmonary edema refractory to vasodilator and diuretic therapy (Figure 1C).
(A,
B) Transesophageal echocardiography showed large vegetation (arrow) of aorta.
IDR-13-2245-g0002.jpg
PMC7360421_01_IDR-13-2245-g0002.jpg
F0002
Periaortic thickening with echo-free space around aorta (abscess) extended to the intervalvular fibrosa (Figure 2A and B).
(A) Dichotomous branching hyphae in KOH preparation (magnification 40x). (B) Dichotomous branching hyphae in PAS stain (magnification 40x). (C) The microscopic appearance of Aspergillus flavus, showing an echinulate colorless conidiophore and a globose vesicle covered by uniseriate phialides with globose echinulate conidia.
IDR-13-2245-g0003.jpg
PMC7360421_01_IDR-13-2245-g0003.jpg
F0003
Direct microscopic examination (KOH preparation, 20%) of tissue biopsies showed a mass of dichotomous branching hyphae (Figure 3A), which was confirmed by histopathology (periodic acid-Schiff staining, Figure 3B). Conidia were globose to subglobose and echinulate (Figure 3C).
Agarose-gel electrophoresis of ss-tubulin PCR products. Lane N, negative control; lane A, DNA extracted from negative blood culture; lane B DNA extracted from colonies grown on SDA; lane M, 100,bp DNA size marker.
IDR-13-2245-g0004.jpg
PMC7360421_01_IDR-13-2245-g0004.jpg
F0004
Accurate identification of grown Aspergillus colonies was performed by polymerase chain reaction (PCR) assay using the two universal fungal primers Bt2a and Bt2b targeting the beta-tubulin gene (Figure 4). Amplicons were sequenced and compared with the GenBank database (https://blast.ncbi.nlm.nih.gov/Blast.cgi) for final identification at species level. The beta-tubulin amplicon from the negative blood culture sequenced and its DNA-sequence data were in complete agreement with the DNA sequences of A. flavus strain CBS 816.96, similar to the aforementioned finding regarding the colony grown from the explanted valve (Figure 4).