Sir,
Recently, we published a case report entitled, “Nocardial brain abscess in a patient with pulmonary alveolar proteinosis.”[1] Pulmonary alveolar proteinosis, a disease of alveolar accumulation of phospholipoproteinaceous material, has been associated with nocardial brain abscess.[2]
Authors of the present letter reviewed the letter conducted by Fatahi-Bafghi entitled as “Phenotypic and molecular identification of nocardia in brain abscess.”[3] Nocardia is a filamentous bacteria, branched Gram-positive Bacilli, aerobic, and partially acid-fast, and its diagnosis depends on staining and culture.[4] In this case, microscopic study of the brain abscess specimen revealed, long branching, filamentous, Gram-positive elements, suggestive of Nocardia. This agent was acid-fast positive, an important clue, which helped us to differentiate Nocardia from Actinomyces. This identification of Nocardia was further confirmed according to its typical and characteristic culture.
In the paper by Fatahi-Bafghi the author noticed that “phenotypic and molecular methods are necessary for accurate identification in species level of Nocardia;” however, traditional phenotypic characterization of this species is labor intensive, time-consuming and leads to misidentification; hence, the molecular methods are widely used for diagnosis, especially gene sequencing, particularly in identification of Nocardia asteroids and farcinia species, and have proven to be faster and more sensitive.[4,5] With the new molecular analyses, conventional methods are being replaced, and in our case, the laboratory identified the asteroides species with this method.
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References
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