Iranian Journal of Medical Microbiology

Numerous challenges are often addressed during the practical phases of various studies, focusing on isolation and identification of filamentous bacteria such as Nocardia spp. as well as assessing their drug resistance patterns. Based on practical experience the authors have observed, this has greatly helped the authors in minimizing difficulties and tackling problems during research processes.
Nocardia spp. are filamentous bacteria with ecological importance and clinical implications that are characterized by their unique morphologies and pathogenic potentials. These bacteria are primarily recognized for their partially acid-fast characteristics due to the presence of mycolic acids (MA) in their cell wall (CW) (1). Nocardiosis is a chronic infection caused by various species of Nocardia, which can manifest as pulmonary, cutaneous, cerebral and disseminated forms. These conditions primarily affect individuals with compromised immune systems (2). As previously stated, identification of filamentous bacteria, particularly species such as Nocardia, presents several challenges in laboratory settings. These difficulties originate from distinctive characteristics of filamentous bacteria and their particular growth needs, broad-spectrum drug resistance patterns, slow growth rates, and oxygen requirements as well as limitations of the current assessment methods (3).