|Peterson, Stephen - Steve|
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 5/21/2009
Publication Date: 5/21/2009
Citation: Iwen, P.C., Peterson, S.W., Florescu, D.F., Kalil, A.C., Mccomb, R.D., Noel, R.K., Sigler, L. 2009. Molecular identification of Emericella echinulata as a cause of Cerebral Aspergillosis in a patient following small bowel and liver transplantation. Meeting Abstract. Interpretive Summary:
Technical Abstract: Molecular methods are now more commonly used for identification of the aspergilli and their teleomorphs and have led to reports of species not previously recognized as causing human disease. We report the first case of cerebral aspergillosis in a compromised patient caused by Emericella echinulata, the teleomorph of Aspergillus nidulans var. echinulata. A 21 year old female status post small bowel and liver transplantation l0y prior was treated with steroids for rejection one month before admission. She was transferred from another facility in critical condition and intubated on the ventilator to our facility following two seizure episodes. An MRI of the brain showed masses in both the occipital and parietal lobes surrounded with massive edema. A CT scan of the chest showed multifocal pneumonia. Bronchoalveolar and tracheal cultures grew an Aspergillus species. Multiple blood cultures were also positive for Candida krusei. Antifungal therapy included voriconazole, liposomal amphotericin Band micafungin. Histological examination of multiple brain biopsies revealed necrotizing inflammatory lesions with branching septate hyphae compatible with Aspergillus species. Aspergillus species were grown from each tissue. Despite maximal therapy the patient died 13d post admission. The isolate was presumptively identified as Emericella nidulans based on the formation of ascomata and ascospores. Following DNA extraction from culture, a PCR-based assay using the calmodulin gene as the molecular target was done. The amplicon was sequenced (538 bp) and compared to sequences on deposit in GenBank using a BLAST search. The sequence showed a >99% homology with those of E. echinulata. Scanning electron microscopy (SEM) of the ascospore wall morphology, used for phenotypic identification of Emericella species, revealed that the ascospores of the patient's isolate were smooth while those of E. echinulata were echinulate. This report highlights the value of molecular testing for accurate identification of the aspergilli and expands the list of species associated with human disease.