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Background The rare occurrence of cryptococcosis caused by Cryptococcus gattii sensu lato (C. gattii s.l.) leads to the difficulties in studying the molecular epidemiology of this globally emerging disease. Objectives To establish the molecular epidemiological profile of C. gattii s.l. in Taiwan, and understand the genetic relationship between locally endemic and global isolates. Methods A nationwide survey on environmental C. gattii s.l. in Taiwan was conducted from 2017 to 2019. The geographic distribution and molecular epidemiology based on multilocus sequence typing (MLST) data of the environmental isolates were compared with 18 previously collected clinical isolates. Phylogenetic analysis was performed to elucidate the genetic relationship between the global isolates and the isolates endemic to Taiwan. Results From a total of 622 environmental samples, 104 (16.7%) were positive for C. gattii s.l.. Seven sequence types were identified among the environmental isolates. The genetic population structure showed that the environmental and clinical isolates were closely linked by sequence types and geographical locations. Phylogenetic analysis revealed the association between the C. gattii s.l. isolates in Taiwan and those from South America and South Asia. The recombination test suggested that, in Taiwan, the C. gattii sensu stricto (C. gattii s.s). isolates undergo clonal reproduction and sexual recombination, whereas C. deuterogattii isolates were clonal. Conclusions The molecular epidemiology of environmental C. gattii s.l. isolates is closely linked to the clinical isolates. Phylogenetic analysis of the environmental isolates provides an insight into the mechanisms underlying reproduction and dispersal of C. gattii s.l. in Taiwan.

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FDG PET/CT imaging has been used in various medical fields, including neoplastic and infectious diseases, for a long time. We reported a 62-year-old man with fever, chronic cough, arthralgia of the left side of the hip, and body weight loss. Chest radiograph showed increased infiltration in both upper lungs, and the acid-fast stain of sputum was positive. Whole-body PET/CT scan revealed a lesion with intense FDG uptake in the joint of the side left of the hip. Osteoarthritis of the hip was initially impressed by an orthopedist. However, tuberculous arthritis was subsequently confirmed by deep pus culture.

Pseudomonas stutzeri (P. stutzeri) is a Gram-negative, non-fermenting rod. It is a rare pathogen; therefore, its isolation is often associated with colonization or contamination. We herein describe the first reported case of necrotizing pneumonia caused by P. stutzeri in a non-HIV infected patient with previously undiagnosed pulmonary tuberculosis. The isolate was found to be antibiotic resistant, which led to the failure of the initial treatment. This case highlights the unique presentation of necrotizing pneumonia caused by P. stutzeri and the importance of emerging antimicrobial resistance in P. stutzeri.

Summary Cryptococcosis is an opportunistic infection caused by the Cryptococcus species complex. An outbreak of cryptococcosis caused by Cryptococcus gattii (AFLP6/VGII) in North America has indicated the need for studies of this organism and its environmental niche. Difficulties in isolating the Cryptococcus spp. because of the overgrowth of filamentous fungi onto culture media and its low fungal population size under natural conditions limit studies of these pathogenic yeasts. We designed a selective medium that inhibits the growth of environmental filamentous fungi but does not inhibit that of Cryptococcus cells. After enrichment in acidified YPD media and inoculation onto selective media, Cryptococcus cells in brown‐coloured colonies were isolated from environmental materials. This two‐step method is useful for isolating environmental members of the Cryptococcus species complex, which is essential for further studies involving diversity and the microbe–environment relationship of this yeast.

Meningitis caused by Cryptococcus tetragattii fungus is rare and has been found in specific geographic regions. We report a case of meningitis caused by C. tetragattii (molecular type VGIV) in an immunocompetent patient in Taiwan. The patient had traveled to Egypt and was positive for granulocyte-macrophage colony-stimulating factor autoantibody.

Colletotrichum gloeosporioides species complex (CGSC) is the major pathogen causing strawberry anthracnose in Taiwan. Benzimidazoles and strobilurins are common fungicides used to control strawberry anthracnose. A total of 108 CGSC isolates were collected from five major strawberry-producing areas in Taiwan. The half-maximal effective concentration (EC 50 ) values of most CGSC isolates for benomyl (59 isolates), carbendazim (70 isolates), and thiabendazole (63 isolates) were higher than 500 µg a.i./mL. Strobilurin tests showed that the EC 50 values of most CGSC isolates for azoxystrobin (66 isolates), kresoxim-methyl (42 isolates), and trifloxystrobin (56 isolates) were higher than 500 µg a.i./mL. However, most CGSC isolates were sensitive to pyraclostrobin at 100 µg a.i./mL. Fungicide tests indicated that CGSC isolates show multi-resistance to benzimidazoles and strobilurins. Benzimidazole-resistant isolates were associated with a point mutation in codon 198 of the β-tubulin gene, and strobilurin-resistant isolates did not correspond with mutation in the cyt b gene or alternative oxidase activity.