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Background: Nocardiosis, a rare but serious infection caused by Grampositive, aerobic actinomycetes, primarily affects immunocompromised individuals. This report highlights an uncommon case of pulmonary nocardiosis in an immunocompetent patient leading to acute hypoxic respiratory failure. Case Presentation: A 45-year-old male gardener with no significant past medical history presented with acute dyspnea, pleuritic chest pain, fever, night sweats, and weight loss. Physical examination revealed respiratory distress and hypoxia. Imaging showed bilateral alveolar infiltrates and cavitary lesions. Sputum analysis identified Gram-positive branching filamentous bacteria, and Nocardia species were cultured. HIV test was negative. Management: The patient was admitted to the ICU and treated with high-flow oxygen therapy and empirical antibiotics (trimethoprim-sulfamethoxazole [TMP-SMX] and meropenem). Upon culture results, TMP-SMX was continued, and meropenem was discontinued. The patient showed significant improvement and was discharged on oral TMP-SMX for a six-month course. Discussion: This case underscores the importance of considering pulmonary nocardiosis in acute respiratory failure, even in immunocompetent patients. Early diagnosis and appropriate treatment are crucial for favorable outcomes. Conclusion: Pulmonary nocardiosis can cause severe respiratory symptoms in otherwise healthy individuals. Prompt recognition and treatment are essential to manage this potentially life-threatening condition effectively. [ABSTRACT FROM AUTHOR]

Background: Nocardiosis, a rare but serious infection caused by Gram-positive, aerobic actinomycetes, primarily affects immunocompromised individuals. This report highlights an uncommon case of pulmonary nocardiosis in an immunocompetent patient leading to acute hypoxic respiratory failure. Case Presentation: A 45-year-old male gardener with no significant past medical history presented with acute dyspnea, pleuritic chest pain, fever, night sweats, and weight loss. Physical examination revealed respiratory distress and hypoxia. Imaging showed bilateral alveolar infiltrates and cavitary lesions. Sputum analysis identified Gram-positive branching filamentous bacteria, and Nocardia species were cultured. HIV test was negative. Management: The patient was admitted to the ICU and treated with high-flow oxygen therapy and empirical antibiotics (trimethoprim-sulfamethoxazole [TMP-SMX] and meropenem). Upon culture results, TMP-SMX was continued, and meropenem was discontinued. The patient showed significant improvement and was discharged on oral TMP-SMX for a six-month course. Discussion: This case underscores the importance of considering pulmonary nocardiosis in acute respiratory failure, even in immunocompetent patients. Early diagnosis and appropriate treatment are crucial for favorable outcomes. Conclusion: Pulmonary nocardiosis can cause severe respiratory symptoms in otherwise healthy individuals. Prompt recognition and treatment are essential to manage this potentially life-threatening condition effectively.

Abstract The purpose of the present study was to evaluate the in vitro activity of tedizolid against several clinically significant species of Nocardia by comparing with that of linezolid. A total of 286 isolates of Nocardia species, including 236 clinical isolates recovered from patients in Japan and 50 strains (43 species) purchased from NITE Biological Resource Center, were studied. Antimicrobial susceptibility testing was performed using the broth microdilution method. For the 286 Nocardia isolates, the minimal inhibitory concentration (MIC)50 and MIC90 values of tedizolid were 0.25 and 0.5 μg/ml, and those of linezolid were 2 and 2 μg/ml, respectively. The distribution of the linezolid/tedizolid ratios (MICs of linezolid/MICs of tedizolid) showed that tedizolid had four- to eight-fold higher activity than linezolid in 96.1% (275/286) of Nocardia isolates. Both the tedizolid and linezolid MIC90 values for Nocardia brasiliensis were two-fold higher than those for the other Nocardia species. Both tedizolid and linezolid had low MIC values, 0.25–1 μg/ml and 0.5–4 μg/ml, respectively, even against nine isolates (five species) that were resistant to trimethoprim/sulfamethoxazole. One Nocardia sputorum isolate showed reduced susceptibility to tedizolid (4 μg/ml). Bioinformatics analysis suggests different resistance mechanisms than the oxazolidinone resistance seen in enterococci and staphylococci.

Pulmonary nocardiosis is a rare infectious disorder mainly affecting immunocompromised patients. It may remain cryptic which gradually progresses in its course. Our patient was a 37 years old immunocompetent female who presented with radiological picture of left upper lobe opacification. She was treated with empirical anti tuberculosis treatment outside, no radiological improvement seen. After she reported here, she was evaluated with bronchoscopy with biopsy and bronchial wash culture showed Nocardia species. She was managed with trimethoprim-sulphamethoxazole and amikacin with regular follow up for 6 months. She had radiological resolution and clinical improvement after 4 months of treatment. Hence we made the diagnosis of this rare infection in immunocompetent individual and successfully treated her, which was mistreated as pulmonary tuberculosis elsewhere.

Mycobacterium avium complex pulmonary disease (MAC‐PD) is sometimes accompanied by co‐infection with other pathogenic microorganisms such as Pseudomonas aeruginosa and Haemophilus influenzae. However, co‐infection with Nocardia spp. has been rarely reported. We report on a patient diagnosed as having co‐infection with Nocardia after treatment for MAC‐PD, which was successfully treated using trimethoprim‐sulfamethoxazole (TMP‐SMX). A 74‐year‐old woman with MAC‐PD was admitted to our hospital to undergo re‐examination for pathogenic microorganisms because chest computed tomography (CT) findings did not improve after treatment for MAC‐PD. She underwent bronchoscopy and Nocardia spp. was detected from bronchoalveolar lavage fluid culture. Chest CT findings improved after 6 months of treatment using TMP‐SMX. Co‐infection with other pathogenic microorganisms should be considered when chest CT findings worsen after adequate treatment of MAC‐PD. Chest CT findings of Nocardia pulmonary disease in immunocompetent patients can mimic those of MAC‐PD and should therefore be differentiated one from the other. [ABSTRACT FROM AUTHOR]

Abstract Mycobacterium avium complex pulmonary disease (MAC‐PD) is sometimes accompanied by co‐infection with other pathogenic microorganisms such as Pseudomonas aeruginosa and Haemophilus influenzae. However, co‐infection with Nocardia spp. has been rarely reported. We report on a patient diagnosed as having co‐infection with Nocardia after treatment for MAC‐PD, which was successfully treated using trimethoprim‐sulfamethoxazole (TMP‐SMX). A 74‐year‐old woman with MAC‐PD was admitted to our hospital to undergo re‐examination for pathogenic microorganisms because chest computed tomography (CT) findings did not improve after treatment for MAC‐PD. She underwent bronchoscopy and Nocardia spp. was detected from bronchoalveolar lavage fluid culture. Chest CT findings improved after 6 months of treatment using TMP‐SMX. Co‐infection with other pathogenic microorganisms should be considered when chest CT findings worsen after adequate treatment of MAC‐PD. Chest CT findings of Nocardia pulmonary disease in immunocompetent patients can mimic those of MAC‐PD and should therefore be differentiated one from the other.

Background This study aimed to present the clinical and radiological characteristics and the outcomes of patients with Nocardia infection of the central nervous system (CNS). Methodology We conducted a retrospective review of patients aged 18 and older admitted between August 1998 and November 2018 with culture-proven nocardiosis and CNS involvement. Results Out of 110 patients with nocardiosis, 14 (12.7%) patients had CNS involvement. The median age was 54.5 (27, 86) years, and 12 (85.7%) patients were male. Overall, 12 (85.7%) patients were immunosuppressed on high doses of glucocorticoids; seven (50%) patients were solid organ transplant recipients. Only eight (57.1%) patients had neurological symptoms at presentation, and the rest were diagnosed with CNS involvement after imaging surveillance. Three distinct radiologic patterns were identified, namely, single or multiple abscesses, focal cerebritis, and small, septic embolic infarcts. All isolates of Nocardia were susceptible to trimethoprim/sulfamethoxazole and amikacin, with susceptibility to linezolid and carbapenems being 90.9% and 79.5%, respectively. Despite receiving antibiotic therapy, six (42.8%) patients died, most of them within weeks of initial admission. All surviving patients underwent prolonged antimicrobial therapy until the resolution of MRI abnormalities. All solid organ transplant recipients recovered. Conclusions Nocardia CNS infection was a rare condition, even among a large, immunosuppressed patient population. CNS imaging surveillance is paramount for immunosuppressed patients with nocardiosis, as CNS involvement influences the choice and duration of therapy. Nocardia antibiotic susceptibility varied widely between strains and the empiric therapy should consist of multiple classes of antimicrobials with CNS penetration. Mortality was high, but all solid organ transplant recipients recovered., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2024, Chirila et al.)

The aim was to record the distribution and susceptibility of Nocardia species in New Zealand. Local and referred isolates were identified by an evolving approach over the study period including conventional phenotypic methods, susceptibility profiles, matrix-assisted laser desorption ionisation-time of flight mass spectrometry (MALDI-TOF) and molecular sequencing. Isolates previously identified as a Nocardia sp. or part of the N. asteroides complex were reidentified by MALDI-TOF and/or molecular methods. Antimicrobial susceptibility to eight antibiotics was performed by standard microbroth dilution. The site of isolation, susceptibility profiles and species distribution were analysed. A total of 383 isolates were tested: N. brasiliensis 23 (6%), N. cyriacigeorgica 42 (11%), N. farcinica 41 (11%), N. nova complex 226 (59%), and 51 (13%) other species/complexes. The respiratory tract was the most common site of infection (244, 64%), with skin and soft tissue the second most common site (104, 27%). All 23 N. brasiliensis isolates were from skin and soft tissue specimens. Almost all isolates (≥98%) were susceptible to amikacin, linezolid and trimethoprim-sulfamethoxazole; 35% and 77% were resistant to clarithromycin and quinolones, respectively. The expected susceptibility profiles of the four common species and complex were observed for most agent-organism parings. Multi-drug resistance was uncommon (3.4%). The spectrum of Nocardia species in New Zealand is similar to overseas reports and our most common group is the N. nova complex. While amikacin, linezolid and trimethoprim-sulfamethoxazole remain good empiric treatment choices, other agents should have their activity confirmed before use., (Copyright © 2023 Royal College of Pathologists of Australasia. Published by Elsevier B.V. All rights reserved.)

This study aimed to isolate and enumerate Nocardiae from the examined raw milk samples. 240 random milk samples were collected from cows, buffaloes, sheep and goats from different localities in Assiut city- Egypt. The incidences of Nocardia spp. were 47.8, 43.3, 53.3 and 66.7% with average counts of 3.8 x104, 4.5x104, 1.4x104 and 7.6x103/CFUmL of the examined samples, respectively. Pathogenicity of the isolates was also studied. N. otitidiscavarium and N. brasiliensis caused sudden death of rats while, N. farcinica and N. carnea strains were non pathogenic. Other species caused several lesions. It was concluded from the study that, Nocardia species are existed in retailed and fresh milk of different farm animals. Most of the isolated strains were highly pathogenic to rats. Consequently, preventive measures should be taken to protect consumers from being infected. [Vet. World 2011; 4(5.000): 201-204]

Twenty-two cases of nocardial infections were diagnosed in our city between 1977- 1998. All patients whose clinical specimens showed Nocardia spp. at Gram stain, which were further confirmed by culture, were selected to be included in the study. Data from patients who were cured were compared with those from patients who died by statistical tests using EPIINFO version 6.04 software. Six isolates were identified as Nocardia asteroides complex, one as Nocardia asteroides sensu stricto and other as Nocardia brasiliensis. We had 17 cases of lung nocardiosis, being one out of them also a systemic disease. Other four cases of systemic nocardiosis were diagnosed: nocardial brain abscesses (one); nocardiosis of the jejunum (one); multiple cutaneous abscesses (one); and a case of infective nocardial endocarditis of prosthetic aortic valve. One patient had a mycetoma by N. brasiliensis. Fifteen (68.2%) out of 22 patients were immunosuppressed, being most (93.3%) by high-doses corticotherapy. Mortality by nocardial infection was 41%; mortality of systemic nocardiosis was 60%. Nocardiosis has a bad prognosis in immunosuppressed patients and also in non-immunosuppressed patients if the diagnosis is delayed. We propose that the delay in diagnosis should be examined in larger series to document its influence in the prognosis of the disease.São apresentados 22 casos de infecção por Nocardia species entre 1977 e 1998, apresentando-se seu quadro clínico e evolução. Todos os pacientes cujos espécimes clínicos mostraram microorganismos sugestivos de Nocardia spp. à coloração de Gram, confirmados posteriormente por cultura, foram incluídos no estudo. Os dados dos pacientes que obtiveram cura foram comparados com aqueles dos pacientes que foram a óbito pelo programa EPIINFO versão 6.04; nível de significância menor que 5% foi considerado estatisticamente significativo. Foram obtidos 22 casos de infecção por Nocardia spp.: seis isolamentos identificados como Nocardia asteroides complex, um como Nocardia asteroides sensu stricto e outro como Nocardia brasiliensis, enquanto os restantes foram identificados como Nocardia spp. Tivemos 17 casos de nocardiose pulmonar (um com disseminação). Tivemos outros quatro casos de nocardiose sistêmica: múltiplos abscessos cerebrais (um); endocardite infecciosa de prótese valvular aórtica (um); nocardiose de intestino delgado (um); abscessos cutâneos múltiplos por Nocardia spp (um). Um paciente apresentou micetoma por Nocardia brasiliensis. Imunossupressão esteve presente em 15 pacientes (68,2%), predominantemente por corticoterapia (93,3%). Nossa mortalidade foi 41%; a mortalidade dos pacientes com nocardiose sistêmica foi de 60%. A nocardiose tem pior prognóstico em pacientes imunossuprimidos e em pacientes com nocardiose sistêmica.

The soil-borne pathogen Nocardia spp. causes severe cutaneous, pulmonary and central nervous system infections. Against them, co-trimoxazole (SXT) constitutes the mainstay of antimicrobial therapy. However, some Nocardia strains show resistance to SXT, but the underlying genetic basis is unknown. We investigated the presence of genetic resistance determinants and class 1-3 integrons in 76 SXT-resistant Nocardia strains by PCR and sequencing. By E-test, these clinical strains showed SXT MICs of ≥32:608 mg/L (ratio of 1:19 for trimethoprim: sulfamethoxazole). They belonged to 12 species, being the main representatives N. farcinica (32%), followed by N. flavorosea (6.5%), N. nova (11.8%), N. carnea (10.5%), N. transvalensis (10.5%) and Nocardia spp. (6.5%). The prevalence of resistance genes in the SXT-resistant strains was as follows: sul1 and sul2 93.4% and 78.9% respectively, dfrA(S1) 14.7%, blaTEM-1 and blaZ 2.6% and 2.6% respectively, VIM-2 1.3%, aph(3´)-IIIa 40.8%, ermA, ermB, mefA and msrD 2.6%, 77.6%, 14.4%, and 5.2% respectively, and tet(O), tet(M), and tet(L) 48.6%, 25.0% and 3.9% respectively. Detected amino acid changes in GyrA were not related to fluoroquinolone resistance, but probably linked to species polymorphism. Class 1 and 3 integrons were found in 93.42% and 56.57% strains, respectively. Class 2 integrons and sul3 genes were not detected. Other mechanisms, different than dfrA(S1), dfrD, dfrF, dfrG and dfrK, could explain the strong trimethoprim resistance shown by the other 64 strains. For first time, resistance determinants commonly found in clinically important bacteria were detected in Nocardia spp. sul1, sul2, erm(B) and tet(O) were the most prevalent in the SXT-resistant strains. The similarity in their resistome could be due to a common genetic platform, in which these determinants are co-transferred

The soil-borne pathogen Nocardia sp. causes severe cutaneous, pulmonary, and central nervous system infections. Against them, co-trimoxazole (SXT) constitutes the mainstay of antimicrobial therapy. However, some Nocardia strains show resistance to SXT, but the underlying genetic basis is unknown. We investigated the presence of genetic resistance determinants and class 1-3 integrons in 76 SXT-resistant Nocardia strains by PCR and sequencing. By E test, these clinical strains showed SXT minimum inhibitory concentrations of ≥32:608 mg/L (ratio of 1:19 for trimethoprim: sulfamethoxazole). They belonged to 12 species, being the main representatives Nocardia farcinica (32%), followed by N. flavorosea (6.5%), N. nova (11.8%), N. carnea (10.5%), N. transvalensis (10.5%), and Nocardia sp. (6.5%). The prevalence of resistance genes in the SXT-resistant strains was as follows: sul1 and sul2 93.4 and 78.9%, respectively, dfrA(S1) 14.7%, blaTEM-1 and blaZ 2.6 and 2.6%, respectively, VIM-2 1.3%, aph(3')-IIIa 40.8%, ermA, ermB, mefA, and msrD 2.6, 77.6, 14.4, and 5.2%, respectively, and tet(O), tet(M), and tet(L) 48.6, 25.0, and 3.9%, respectively. Detected amino acid changes in GyrA were not related to fluoroquinolone resistance, but probably linked to species polymorphism. Class 1 and 3 integrons were found in 93.42 and 56.57% strains, respectively. Class 2 integrons and sul3 genes were not detected. Other mechanisms, different than dfrA(S1), dfrD, dfrF, dfrG, and dfrK, could explain the strong trimethoprim resistance shown by the other 64 strains. For first time, resistance determinants commonly found in clinically important bacteria were detected in Nocardia sp. sul1, sul2, erm(B), and tet(O) were the most prevalent in the SXT-resistant strains. The similarity in their resistome could be due to a common genetic platform, in which these determinants are co-transferred. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Medical Mycology / Journal de Mycologie Médicale is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study aimed to isolate and enumerate Nocardiae from the examined raw milk samples. 240 random milk samples were collected from cows, buffaloes, sheep and goats from different localities in Assiut city- Egypt. The incidences of Nocardia spp. were 47.8, 43.3, 53.3 and 66.7%with average counts of 3.8 x104, 4.5x104, 1.4x104 and 7.6x103/CFUmL of the examined samples, respectively. Pathogenicity of the isolates was also studied. N. otitidiscavarium and N. brasiliensis caused sudden death of rats while,N. farcinica and N. carnea strains were non pathogenic. Other species caused several lesions. It was concluded from the study that,Nocardia species are existed in retailed and fresh milk of different farm animals. Most of the isolated strains were highly pathogenic to rats. Consequently, preventive measures should be taken to protect consumers from being infected. [ABSTRACT FROM AUTHOR]

Copyright of Archivos de Bronconeumología (English Edition) is the property of Sociedad Espanola de Neumologia y Cirugia Toracica (SEPAR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Five aerobic actinomycete strains isolated from patients in Japan were assigned provisionally to the genus Nocardia based on morphological and physiological characteristics. The five strains, IFM 10481, IFM 0668, IFM 0901, IFM 0583 and IFM 0342, were not classified into any Nocardia species reported as infectious agents in Japan. Therefore, they were studied further to determine their specific taxonomic positions. Detailed chemotaxonomic and physiologic characterization and 16S rDNA sequence data of the five strains showed that they belonged to respective species of Nocardia carnea, N. elegans, N. paucivorans, N. puris and N. takedensis. This is the first isolation report of these five Nocardia species from patients in Japan. [ABSTRACT FROM AUTHOR]

Abstract: The phytoestrogen daidzein was metabolized by Nocardia species NRRL 5646 to give two metabolites obtained by hydroxylation and methylation. These metabolites were spectrally characterized as 7-methoxy-4′-hydroxyisoflavone (isoformononetin) and 7,8-dimethoxy-4′-hydroxyisoflavone. Mortierella isabellina ATCC 38063 was able to metabolize daidzein to the unusual metabolite daidzein-4′-rhamnopyranoside. [Copyright &y& Elsevier]