The genus Aspergillus, which consists of a few hundred opportunistic mold species found in various climatic conditions, causes diseases including localized infections, fatal diseases, allergic responses, and inhaled conidia in humans. Herein, we present an overview of the most common diseases and allergic infections caused by Aspergillus species and their associated health hazards in various indoor environments worldwide.

Azole resistance in Aspergillus is emerging in European and Asian countries. As azoles are mainstay of therapy in the management of aspergillosis, azole resistance has serious implications in patient management. We report the emergence of resistance to triazoles in environmental Aspergillus fumigatus isolates in Iran. The TR34/L98H mutation was the only resistance mechanism. Overall 3.3% of the A. fumigatus isolates from hospital surroundings in Sari and Tehran had the same TR34/L98H STRAf genotype and were related to some resistant clinical and environmental TR34/L98H isolates from the Netherlands and India. It is emphasised that routine resistance surveillance studies focusing on environmental and clinical samples are warranted to yield the true prevalence of azole resistance in A. fumigatus in Iran.

In patients with preexisting lung disease, especially a cavity, Aspergillus can infect the surface of the cavity, causing chronic cavitary pulmonary aspergillosis (CCPA), and may form an aspergilloma, collectively called chronic pulmonary aspergillosis (CPA). In the present study, we assessed tuberculosis (TB) patients for CPA based on culture and serological methods. During a period of 1 year (from March 2013 to March 2014), we studied 124 patients with TB (94 with current TB and 30 with previous TB) at Masih Daneshvari Hospital in Tehran, Iran. Sputum specimens were analyzed by direct microscopic examination (DME) and fungal culture. The clinical and radiological features of all patients were recorded, to categorize the patients into CCPA and aspergilloma. All patients were screened for serum-specific IgG against A. fumigatus, by enzyme-linked immunosorbent assay (ELISA). Out of 124 patients with TB (66 male, age range: 10-91 years), 48 patients (38.7 %) exhibited residual cavities. Eighteen (14.5 %) patients had cavities with pleural thickening. A round-shaped mass lesion was detected in six patients (6.8 %). DME was positive in ten patients for septate fungal hyphae. A. fumigatus was grown from 14 samples. Fifty-five (44.3 %) cases were positive for serum-specific IgG against A. fumigatus. Of 124 patients with TB, 3 (2.4 %) met criteria for aspergilloma and 14 (11.3 %) for CCPA. CPA is a common clinical presentation in individuals with healed TB in Iran, as reported by previous studies from other countries.

Based on epidemiological studies, Aspergillus candidus has been demonstrated as an emerging fungal agent of toenail onychomycosis. Here we report a case of a toenail infection caused by A. candidus in a healthy 60-year-old woman. Based on macroscopic and microscopic characteristics of the culture as well as nucleotide sequencing of 28S region, the causative agent was identified as A. candidus.

In recent decades the incidence of Candida endocarditis has increased dramatically. Despite the application of surgery and antifungal therapy, Candida endocarditis remains a life-threatening infection with significant morbidity and mortality. We report a 37-year-old male drug abuser presenting with high fever, chest pain, loss of appetite and cardiac failure. His echocardiography revealed mobile large tricuspid valve vegetations. Fungal endocarditis was confirmed by culturing of the resected vegetation showing mixed growth of Candida albicans and Candida tropicalis, although three consecutive blood cultures were negative for Candida species. Phenotypic identification was reconfirmed by sequencing of the internal transcribed spacer (ITS rDNA) region. The patient was initially treated with intravenous fluconazole (6 mg kg "1 per day), followed by 2 weeks of intravenous amphotericin B deoxycholate (1 mg kg "1 per day). Although MICs were low for both drugs, the patient's antifungal therapy combined with valve replacement failed, and he died due to respiratory failure.