Diagnostic significance ofAspergillusspecies isolated from respiratory samples in an adult pneumology ward

Abstract

Although the diagnostic significance of isolating Aspergillus spp. from respiratory cultures has been studied in immunocompromised hosts with invasive pulmonary aspergillosis (IPA), little is known of such infections in immunocompetent patients with other forms of aspergillosis. In this study of adult pneumology ward patients, we examined the association between Aspergillus spp. and disease prevalence. Laboratory records from April 1998 to March 2009 were reviewed to identify patients with Aspergillus spp. in respiratory samples. Correlations between the isolated species and clinical characteristics of patients were evaluated. During the study period, 165 Aspergillus spp. isolates were detected in the respiratory cultures of 139 patients. Of these patients, 62 (45%) were colonized with Aspergillus spp. and displayed no clinical symptoms of aspergillosis, while 77 (55%) had a form of pulmonary aspergillosis, characterized as either chronic necrotizing pulmonary aspergillosis (CNPA) (48%), aspergilloma (29%), IPA (13%), or allergic bronchopulmonary aspergillosis (ABPA) (10%). The dominant species were Aspergillus fumigatus (41%), A. niger (32%), and A. versicolor (12%). A. fumigatus was most commonly isolated in patients with IPA, aspergilloma, and CNPA, whereas A. niger was the dominant species in colonized patients and those with ABPA. Isolation of an Aspergillus spp. from respiratory samples does not confirm it as the etiologic pathogen because airway colonization by Aspergillus spp. is a common feature in several chronic lung diseases. Repeated isolation of the identical Aspergillus species and detection of anti-Aspergillus antibodies and/or Aspergillus antigens in sera are needed to determine the isolate represents the etiologic agent of disease.

Epidemiological study of Aspergillosis in chickens and human contacts in chicken farms at Kalyoubia Governorate

“…This substantiated what has been reported by (12) 27.5%, (6) 22% and (22) 29% but it is higher than that obtained by (23) 4.8% and lower than recorded by (24) 45%. This discrepancy may be due to massive population growth and urban development which increased the prevalence of fungal infections in certain areas and putting more people at risk (25).…”

Evaluation of the Aspergillus Western Blot IgG Kit for Diagnosis of Chronic Aspergillosis

“…colonization remains a matter of debate. In line with this hypothesis, it has been demonstrated that persistent colonization can induce an antibody response, and according to some authors, this seroconversion should prompt the reinforcement of patient monitoring and/or the start of antifungal therapy (20)(21)(22). The primary interest of including colonized patients in this evaluation is that they are typically those in whom Aspergillus serology is performed.…”

Molecular and Nonmolecular Diagnostic Methods for Invasive Fungal Infections

“…Therefore, repeated isolation of the same Aspergillus spp. or alternative diagnostic tests for invasive aspergillosis should be sought to accurately interpret a positive finding, especially in the absence of host factors (42). However, in the case of critically ill patients, an Aspergillus sp.-positive culture result portends a poor prognosis irrespective of colonization or active infection (43).…”