Clonal outbreak of fluconazole-resistant (FLZR) Candida parapsilosis isolates have been reported in several countries. Despite being the second leading cause of candidemia, the azole resistance mechanisms and the clonal expansion of FLZR C. parapsilosis blood isolates have not been reported in Turkey. Herein, we consecutively collected the C. parapsilosis blood isolates (n=225) from the fifth largest hospital in Turkey (2007–2019), assessed their azole susceptibility pattern using CLSI M27-A3/S4, and sequenced ERG11 for all and MRR1, TAC1, and UPC2 for selected number of C. parapsilosis isolates. The typing resolution of two widely used techniques, AFLP and microsatellite typing (MST), and the biofilm production of FLZR isolates with/without Y132F were compared. Approximately 27% of isolates were FLZR (60/225), among which 90% (54/60) harboured known mutations in Erg11, including Y132F (24/60) and Y132F+K143R (19/60). Several mutations specific to FLZR isolates were found in MRR1, TAC1, and UPC2. AFLP clustered isolates into two clusters, while MST revealed several clusters. The majority of Y132F/Y132F+K143R isolates grouped in clonal clusters, which significantly expanded throughout 2007–2019 in neonatal wards. Candida parapsilosis isolates carrying Y132F were associated with significantly higher mortality and less biofilm production relative to other FLZR isolates. Collectively, we documented the first outbreak of FLZR C. parapsilosis blood isolates in Turkey. The MRR1, TAC1, and UPC2 mutations exclusively found in FLZR isolates establishes basis for future studies, which potentially broaden our knowledge on FLZR mechanisms in C. parapsilosis. MST should be a preferred method for clonal analysis of C. parapsilosis isolates in outbreak scenarios.
The most common type of spinal cord ischemia is bilateral or unilateral anterior spinal artery infarcts due to radicular artery disease with acute or chronic spinal disease and followed by central and transverse infarcts due to extensive spinal cord hypoperfusion and arteriopathy.
Headache, convulsion, behavioral disorder, seizures, and speech disorders were the most frequent clinical symptoms of patients with hemorrhagic CSVT. Specific risk factors, including pregnancy/puerberium, early and extended thrombosis of large sinus, and presence of high blood pressure at admission, are associated with hemorrhagic lesion and unfavorable outcome.
Candida tropicalis is the fourth leading cause of candidemia in Turkey. Although C. tropicalis isolates from 1997 to 2017 were characterized as fully susceptible to antifungals, the increasing global prevalence of azole-non-susceptible (ANS) C. tropicalis and the association between high fluconazole tolerance (HFT) and fluconazole therapeutic failure (FTF) prompted us to re-evaluate azole susceptibility of C. tropicalis in Turkey. In this study, 161 C. tropicalis blood isolates from seven clinical centers were identified by ITS rDNA sequencing, genotyped by multilocus microsatellite typing, and tested for susceptibility to five azoles, two echinocandins, and amphotericin B (AMB); antifungal resistance mechanisms were assessed by sequencing of ERG11 and FKS1 genes. The results indicated that C. tropicalis isolates, which belonged to 125 genotypes grouped into 11 clusters, were fully susceptible to echinocandins and AMB; however, 18.6% of them had the ANS phenotype but only two carried the ANS-conferring mutation (Y132F). HFT was recorded in 52 isolates, 10 of which were also ANS. Large proportions of patients infected with ANS and HFT isolates (89 and 40.7%, respectively) showed FTF. Patients infected with azole-susceptible or ANS isolates did not differ in mortality, which, however, was significantly lower for those infected with HFT isolates ( P = 0.007). There were significant differences in mortality ( P = 0.02), ANS ( P = 0.012), and HFT ( P = 0.007) among genotype clusters. The alarming increase in the prevalence of C. tropicalis blood isolates with ANS and HFT in Turkey and the notable FTF rate should be a matter of public health concern.
Background Echinocandin resistance rarely occurs in clinical Candida parapsilosis isolates and the underlying mechanism is unknown. Objectives To determine the prevalence of echinocandin resistance and the underlying mechanism for a large collection of C. parapsilosis blood isolates and to determine whether the echinocandin-resistant isolates were clonally related. Methods C. parapsilosis blood isolates (n = 213) were subjected to antifungal susceptibility testing (CLSI M27), for micafungin, anidulafungin, amphotericin B and, if appropriate, caspofungin. Hotspot (HS) 1 and HS2 of FKS1 were sequenced for all isolates (n = 213) and microsatellite typing was performed for echinocandin-resistant isolates. Results All isolates were susceptible to amphotericin B and two isolates were intermediate to anidulafungin (MIC = 4 mg/L), while micafungin resistance was noted in four isolates (MIC >8 mg/L); three of which were also fluconazole resistant and therefore were MDR. Interestingly, micafungin-resistant isolates, but not those intermediate to anidulafungin, carried novel mutation R658G in HS1 of Fks1p; three of which also harboured Y132F+K143R in Erg11. The first isolate (MICR1) was recovered in November 2017 from a patient admitted to paediatric gastroenterology who showed therapeutic failure under caspofungin treatment. MICR2–MICR4 were collected during 2018–19 and were recovered from three echinocandin-naive paediatric-surgery patients; the isolates shared the same genotype. Conclusions Herein, for the first time (to the best of our knowledge), we identified micafungin-resistant C. parapsilosis blood isolates harbouring a novel mutation in HS1 of FKS1, which was likely attributable to in vitro micafungin resistance and in vivo caspofungin therapeutic failure. The acquisition of micafungin-resistant C. parapsilosis isolates in echinocandin-naive patients likely implicates clonal expansion, as supported by the close genetic relatedness of MICR2–MICR4.
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