Pulmonary Infection Secondary to Chrysosporium zonatum in an Immunocompetent Man

Voriconazole treatment of pulmonary mycosis caused by Chrysosporium zonatum after treatment for pulmonary tuberculosis

Chrysosporium zonatum is a soil-dwelling fungus that rarely causes pulmonary infections, and a small number of cases have been reported to date. A 74-year-old man, who had previously been treated for tuberculosis, presented with symptoms of low-grade fever, anorexia, cough, and bloody sputum. Chest computed tomography (CT) showed a thick-walled cavitary lesion in the right upper lobe, in which there was a suspected mycotic mass. Initially, the patient was suspected to have chronic aspergillosis due to positive serum anti-Aspergillus antibodies. However, bronchoscopic culture revealed the growth of C. zonatum. Symptoms and imaging findings improved with administration of voriconazole for 18 months. Infection by C. zonatum is very rare and is difficult to differentiate from aspergillosis by clinical features. Clinicians should be aware of the possibility of coinfection with C. zonatum and Aspergillus sp. Voriconazole may be an effective treatment option.

The Interaction of Human Pathogenic Fungi With C-Type Lectin Receptors

Fungi, usually present as commensals, are a major cause of opportunistic infections in immunocompromised patients. Such infections, if not diagnosed or treated properly, can prove fatal. However, in most cases healthy individuals are able to avert the fungal attacks by mounting proper antifungal immune responses. Among the pattern recognition receptors (PRRs), C-type lectin receptors (CLRs) are the major players in antifungal immunity. CLRs can recognize carbohydrate ligands, such as β-glucans and mannans, which are mainly found on fungal cell surfaces. They induce proinflammatory immune reactions, including phagocytosis, oxidative burst, cytokine, and chemokine production from innate effector cells, as well as activation of adaptive immunity via Th17 responses. CLRs such as Dectin-1, Dectin-2, Mincle, mannose receptor (MR), and DC-SIGN can recognize many disease-causing fungi and also collaborate with each other as well as other PRRs in mounting a fungi-specific immune response. Mutations in these receptors affect the host response and have been linked to a higher risk in contracting fungal infections. This review focuses on how CLRs on various immune cells orchestrate the antifungal response and on the contribution of single nucleotide polymorphisms in these receptors toward the risk of developing such infections.