ABSTRACT
We reported a case of aspergillosis presented as cholangitis in a patient after liver transplantation, even with prophylactic use of fluconazole. The patient had multiple predisposing factors, such as leukocytopenia, immunosuppressive drug therapy. He died 2 days after an exploratory laparotomy was carried out. The histopathologic finding of biopsy specimen from biliary tract was positive for Aspergillus. And the pathogen was identified as Aspergillus flavus by mycological culture and PCR. The patient was confirmed as a case of Aspergillosis of biliary tract that was responded poorly to fluconazole. This indicated that azole should have been switched to more effective antifungal agents at earlier stage when the patients responded poorly to the original treatment.
Subject(s)
Aspergillosis/diagnosis , Aspergillus flavus/isolation & purification , Biliary Tract/microbiology , Biliary Tract/pathology , Liver Transplantation/adverse effects , Aspergillosis/microbiology , Aspergillosis/pathology , Aspergillus flavus/genetics , Aspergillus flavus/growth & development , Chemoprevention/methods , Drug Resistance, Fungal , Fatal Outcome , Fluconazole/therapeutic use , Histocytochemistry , Humans , Immunocompromised Host , Male , Microscopy , Middle AgedABSTRACT
Objective To clarify the quorum sensing and identify the quorum sensing molecular of Cryptococcus neoformans. Methods The growth of Cryptococcus neoformans TUP1 △ strain at different inoculum size was observed. The culture filtrate of high cell density TUP1△ strain was collected and plated on medium with low density TUP1△ cell, and the growth of low cell density TUP1△ was recorded. Finally, the active molecule in culture filtrate was purified and identified.Results The growth of Cryptococcus neoformans TUP1△ strain was density dependent and the colony could be normally formed only above a specific density. The filtrate from a high cell density TUP1△culture could promote the growth of low cell density TUP1△, and the active molecule in this culture filtrate was identified to be an oligopeptide composed of 11 amino acids pepride, named quorum sensing peptide 1(QSP1). QSP1 was artificially synthesized, which could also promote the colony forming of TUP1△ strain inoculated at low cell density. Conclusion Quorum sensing exists in Cryptococcus neoformans, and the quorum sensing molecular is QSP1.
