An immunosuppressed patient with systemic vasculitis suffering from cerebral abscesses due to Nocardia farcinica identified by 16S rRNA gene universal PCR

Nocardiaspp. are Gram-positive, partially or vari-ably acid-fastfilamentous, branching rods of aerobicactinomycetes [1]. The most common primary site forinfection in man is the respiratory tract [1,2]. Brainabscess is the most common clinical manifestationof central nervous system (CNS) infection [1]. Themajority of the patients affected have underlyingchronic diseases or suffer from endogenous or drug-induced immunosuppression [2,3], but the pathogencan also infect persons without any risk factors [2].However, the course of the infection tends to be moresevere and prolonged in immunocompromised hoststhan in patients with normal cell-mediated immunity[4]. The symptoms of brain abscessesare often non-specific and include the classic triad of fever, headacheand focal neurological deficiency [2,3]. It is importantto establish the appropriate microbial diagnosis, as thelist of potential microbial invaders among immuno-suppressed patients, especially in transplant recipients,is large and antibiotic therapy differs [3]. The diagnos-tic work-up should include active diagnostic investiga-tions for uncommon pathogens, such as radiologicalimaging, measurement of arabinitol in the urine,bronchoscopy in combination with bronchoalveolarlavage, biopsy and histological examinations, sputumexaminations, culturing for bacteria, fungi and viralagents in body fluids, serological tests and microscopy,including acid-faststaining for opportunistic patho-gens. Crypyococcus neoformans, Listeria monocyto-genes, Aspergillus fumigatus, conventional bacteria,viral agents, Nocardia, Mycobacterium tuberculosis, MucoraceaeandToxoplasma gondii havebeenreportedto cause CNS infections in immunocompromisedpatients [3]. Nocardial cultures often demonstrategrowth too late to be clinically useful or are discardedtoo early to allow growth of Nocardia[2].It is thus important to prolong the incubation periodfor up to 3 weeks or more, and to use specially designedgrowth media to allow the growth of uncommonpathogens [1]. A new technique for fast and reliablediagnoses of CNS infections and uncommon patho-gens such as Nocardiaspp. has been needed for a longtime [2].