Long-distance population dispersal leaves its characteristic signature in genomes, namely, reduced diversity and increased linkage between genetic markers. This signature enables historical patterns of range expansion to be traced. Herein, we use microsatellite loci from the human pathogen Coccidioides immitis to show that genetic diversity in this fungus is geographically partitioned throughout North America. In contrast, analyses of South American C. immitis show that this population is genetically depauperate and was founded from a single North American population centered in Texas. Variances of allele distributions show that South American C. immitis have undergone rapid population growth, consistent with an epidemic increase in postcolonization population size. Herein, we estimate the introduction into South America to have occurred within the last 9,000 -140,000 years. This range increase parallels that of Homo sapiens. Because of known associations between Amerindians and this fungus, we suggest that the colonization of South America by C. immitis represents a relatively recent and rapid codispersal of a host and its pathogen.

In this group of patients, subgingival colonization of some yeasts, especially C. albicans, was associated with the severity of CP.

Both immunoreactive proteins and B-cell epitopes of C. gattii genotype VGII that were potentially targeted by a host humoral response were identified. Considering the evolutionary relevance of the identified proteins, we may speculate that they could be used as the initial targets for recombinant protein and peptide synthesis aimed at the development of immunodiagnostic tools for cryptococcosis.

The aim of this study was to describe the CT scan abnormalities in 15 patients with acute pulmonary coccidioidomycosis. Retrospective analysis of chest CT scans from 15 patients with acute pulmonary coccidioidomycosis was performed. The final diagnosis included the finding of Coccidioides immitis in mycology and/or histopathology, complemented by serology. Two radiologists evaluated the CT scans to study the type, size, profusion and localization of the findings. The final decisions were defined by consensus. CT scans showed multiple bilateral nodules in 13 patients and solitary nodules associated with consolidation in 2 cases. The nodules had ill-defined contours, ranging from 0.5 cm to 3.0 cm in diameter, which were predominant in the lower lobes in 11 cases. Cavitation of nodules was observed in 13 cases and coalescence in 7. Nodule-associated abnormalities were found in 13 cases, comprising interlobular septal thickening (n = 7) and consolidations (n = 6). Other abnormalities included lymph node enlargement (n = 6) and small pleural effusion (n = 2). In conclusion, the main CT finding in patients with acute coccidioidomycosis was that of multiple nodules (0.5-3.0 cm) at the lungs bases; a significant proportion of the remaining cases also showed other abnormalities. A diagnosis of coccidioidomycosis must be considered in patients with multiple lung nodules that are either in, or have recently been transported to, areas of endemic mycosis.

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