Pneumocystis jirovecii colonization rates in healthy patients are unclear. Previously published studies suggest that the fungus could play a role in the physiopathology and progression of chronic respiratory diseases.

Identification of dermatophytes is usually performed through morphological analyses. However, it may be hindered due to the discovery of new species and complexes and, with some isolates, by the absence of fructification. Matrix-assisted laser desorption/ionisation-time-of-flight mass spectrometry (MALDI-TOF MS) seems to be an option for improving identification.

We present the case of a twenty six year-old woman with rheumatoid arthritis, treated with certolizumab. She sought medical attention due to cough, fever and night sweats. X-ray exam showed a miliary pneumonia. She was treated for tuberculosis and 50days later she presented with aphasia. Magnetic nuclear resonance revealed brain lesions. Histoplasma capsulatum PCR test and urinary antigen were positive, so an antifungal treatment with voriconazole was started. Visual adverse effects forced to change the antifungal schedule in both the length of treatment and the antifungal drug. With this measure the patient progressed favorably. The test of urinary Histoplasma capsulatum antigen and PCR amplification were key to make a diagnosis and also for a follow-up.

The genus Microthecium contains 31 species worldwide distributed. Most of them are saprobic on soil and plant debris, but a few have been reported as mycoparasites on hypocrealean fungi. By contrast, this genus has never been reported as phytopathogenic, nor endophytic.

The clinical significance of the filamentous basidiomycetes isolated from clinical samples is not always clear. Thus, these fungi have been considered environmental contaminants traditionally.

Aspergillus flavus and Aspergillus fumigatus are commonly involved in fungal endophthalmitis. However, other less pathogenic species of the genus are also causal agents of opportunistic infections. Aspergillus hiratsukae, a species within Aspergillus section Fumigati, is an uncommon fungus responsible for a few infectious cases worldwide.

Paracoccidioidomycosis is an endemic mycosis caused by members of the Paracoccidioides genus. Brazil remains the focus area and, to a lesser extent, the disease has been reported from Argentina, Colombia and Venezuela.

Candida bloodstream infection (CBSI) is a growing problem among patients with cancer.

Early diagnosis of candidemia is critical for the correct management and treatment of patients.

Aspergillus fumigatus is a ubiquitous opportunistic pathogen. This fungus can acquire resistance to azole antifungals due to different mutations in the cyp51A gene. Azole resistance has been observed in several continents and appears to be a globally distributed phenomenon. Specific mutations in cyp51A that lead to azole resistance, such as the TR34/L98H modification, have been reported.

Pneumocystis carinii is an opportunistic fungal pathogen that may cause pneumonia and lead to pulmonary fibrosis.

Scedosporium species are considered emerging pathogens causing illness in immunocompetent and immunocompromised hosts.

Candida species are frequently isolated from the oral cavity of patients with cystic fibrosis. However, the information on the role of Candida in cystic fibrosis is scarce.

Post-traumatic Fusarium infection is rare. Arterial occlusive disease, a common vascular disorder in the elderly, often leads to ischemic necrosis of the lower extremities, which in turn increases the likelihood of secondary infections. Those secondary infections can be caused by bacteria, virus, or fungi.

Fungal endocarditis is a low-frequency disease with a challenging diagnosis, as it can be mistaken with bacterial endocarditis. Fungal endocarditis causes higher mortality rates in immunocompromised patients. In the clinical practice, the endocarditis caused by fungi represents up to 10% of all infectious endocarditis cases and has a mortality rate of nearly 50%.

Immune checkpoint inhibitors (ICIs) are a promising new treatment for different types of cancer. The infectious complications in patients taking ICIs are rare.

Fungemia due to uncommon fungi and secondary to multiple risk factors has become an emergent health problem, particularly in oncology patients.

Paracoccidioidomycosis is a neglected tropical disease caused by fungi of the genus Paracoccidioides. A wide range of symptoms is related to the disease; however, lungs and skin are the sites predominantly affected. The disease is mostly seen in people living in rural areas in Latin America.

Neoscytalidiumdimidiatum is an opportunistic dematiaceous fungus belonging to the class Dothideomycetes.

Scedosporiasis is an emerging mycosis that has gained importance in recent years due to its worldwide prevalence. It is caused by species of the Scedosporium apiospermum complex. These species can cause opportunistic infections in immunocompromised patients and, occasionally, in immunocompetent patients as well. The high intrinsic antifungal resistance make these infections difficult to manage.