TY - JOUR
T1 - Use of selective fungal culture media increases rates of detection of fungi in the respiratory tract of cystic fibrosis patients
AU - Hong, Gina
AU - Miller, Heather B.
AU - Allgood, Sarah
AU - Lee, Richard
AU - Lechtzin, Noah
AU - Zhang, Sean X.
PY - 2017/4
Y1 - 2017/4
N2 - The prevalence of fungi in the respiratory tracts of cystic fibrosis (CF) patients has risen. However, fungal surveillance is not routinely performed in most clinical centers in the United States, which may lead to an underestimation of the true prevalence of the problem. We conducted a prospective study comparing the rates of detection for clinically important fungi (CIF), defined as Aspergillus, Scedosporium, and Trichosporon species and Exophiala dermatitidis, in CF sputa using standard bacterial and selective fungal culture media, including Sabouraud dextrose agar with gentamicin (SDA), inhibitory mold agar (IMA), and brain heart infusion (BHI) agar with chloramphenicol and gentamicin. We described the prevalence of these fungi in an adult CF population. A total of 487 CF respiratory samples were collected from 211 unique participants. CIF were detected in 184 (37.8%) samples. Only 26.1% of CIF-positive samples were detected in bacterial culture medium, whereas greater rates of detection for fungi were found in IMA (65.8%; P β 0.001), in SDA (at 30°C, 64.7%; P - 0.005), and in BHI agar (63.0%; P - 0.001). The prevalences of Aspergillus and Scedosporium species were 40.8% and 5.2%, respectively, which are greater than the nationally reported prevalence numbers of 20.4% and 1.9%. Selective fungal culture media and longer incubation periods yielded higher rates of detection for CIF in CF sputum samples compared with that detected in bacterial culture medium, resulting in an underdetection of fungi by bacterial culture alone. The prevalence of fungi in CF may be better estimated by using selective fungal culture media, and this may translate to important clinical decisions.
AB - The prevalence of fungi in the respiratory tracts of cystic fibrosis (CF) patients has risen. However, fungal surveillance is not routinely performed in most clinical centers in the United States, which may lead to an underestimation of the true prevalence of the problem. We conducted a prospective study comparing the rates of detection for clinically important fungi (CIF), defined as Aspergillus, Scedosporium, and Trichosporon species and Exophiala dermatitidis, in CF sputa using standard bacterial and selective fungal culture media, including Sabouraud dextrose agar with gentamicin (SDA), inhibitory mold agar (IMA), and brain heart infusion (BHI) agar with chloramphenicol and gentamicin. We described the prevalence of these fungi in an adult CF population. A total of 487 CF respiratory samples were collected from 211 unique participants. CIF were detected in 184 (37.8%) samples. Only 26.1% of CIF-positive samples were detected in bacterial culture medium, whereas greater rates of detection for fungi were found in IMA (65.8%; P β 0.001), in SDA (at 30°C, 64.7%; P - 0.005), and in BHI agar (63.0%; P - 0.001). The prevalences of Aspergillus and Scedosporium species were 40.8% and 5.2%, respectively, which are greater than the nationally reported prevalence numbers of 20.4% and 1.9%. Selective fungal culture media and longer incubation periods yielded higher rates of detection for CIF in CF sputum samples compared with that detected in bacterial culture medium, resulting in an underdetection of fungi by bacterial culture alone. The prevalence of fungi in CF may be better estimated by using selective fungal culture media, and this may translate to important clinical decisions.
KW - Aspergillus
KW - Brain heart infusion agar
KW - Cystic fibrosis
KW - Exophiala
KW - Fungal culture
KW - Fungi
KW - Inhibitory mold agar
KW - Sabouraud dextrose agar
KW - Scedosporium
KW - Trichosporon
UR - http://www.scopus.com/inward/record.url?scp=85016205963&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85016205963&partnerID=8YFLogxK
U2 - 10.1128/JCM.02182-16
DO - 10.1128/JCM.02182-16
M3 - Article
C2 - 28100601
AN - SCOPUS:85016205963
SN - 0095-1137
VL - 55
SP - 1122
EP - 1130
JO - Journal of clinical microbiology
JF - Journal of clinical microbiology
IS - 4
ER -