-
The Brazilian Journal of Infectious... 2023Nocardiosis is a rare bacterial infection caused by Nocardia spp. However, an increasing incidence has been described whereby data about epidemiology and prognosis are... (Review)
Review
INTRODUCTION
Nocardiosis is a rare bacterial infection caused by Nocardia spp. However, an increasing incidence has been described whereby data about epidemiology and prognosis are essential.
METHODS
A retrospective descriptive study was conducted among patients with positive Nocardia spp. culture, from January 2019 to January 2023, at a Terciary Hospital in Portugal.
RESULTS
Nocardiosis was considered in 18 cases with a median age of 63.8-years-old. At least one immunosuppressive cause was identified in 70% of patients. Five patients had Disseminated Nocardiosis (DN). The lung was the most common site of clinical disease (77.8%) and Nocardia was most commonly identified in respiratory tract samples. The most frequently isolated species were Nocardia nova/africana (n = 7) followed by Nocardia cyriacigeorgica (n = 3) and Nocardia pseudobrasiliensis (n = 3). The majority of the patients (94.4%) received antibiotic therapy, of whom as many as 55.6% were treated with monotherapy. The most frequently prescribed antibiotic was trimethoprim-sulfamethoxazole. Selected antimicrobial agents were generally effective, with linezolid and cotrimoxazole (100% Susceptibility [S]) and amikacin (94% S) having the most activity against Nocardia species. The median (IQR) duration of treatment was 24.2 (1‒51.4) weeks for DN; The overall one-year case fatality was 33.3% (n = 6) and was higher in the DN (66.7%). No recurrence was observed.
CONCLUSION
Nocardiosis is an emerging infectious disease with a poor prognosis, particularly in DN. This review offers essential epidemiological insights and underscores the importance of gaining a better understanding of the microbiology of nocardiosis. Such knowledge can lead to the optimization of antimicrobial therapy and, when necessary, guide appropriate surgical interventions to prevent unfavorable outcomes.
Topics: Humans; Middle Aged; Retrospective Studies; Nocardia; Nocardia Infections; Anti-Bacterial Agents; Trimethoprim, Sulfamethoxazole Drug Combination; Anti-Infective Agents
PubMed: 37802128
DOI: 10.1016/j.bjid.2023.102806 -
International Journal of Systematic and... Oct 2020The taxonomic positions of two novel aerobic, Gram-stain-positive Actinobacteria, designated RB20 and RB56, were determined using a polyphasic approach. Both were...
The taxonomic positions of two novel aerobic, Gram-stain-positive Actinobacteria, designated RB20 and RB56, were determined using a polyphasic approach. Both were isolated from the fungus-farming termite . Results of 16S rRNA gene sequence analysis revealed that both strains are members of the genus with the closest phylogenetic neighbours JCM12860 (98.9 %) and DSM44481 (98.5 %) for RB20 and DSM 44801 (98.3 %), DSM 44290 (98.3 %) and JCM 19832 (98.2 %) for RB56. Digital DNA-DNA hybridization (DDH) between RB20 and JCM12860 and DSM 44481 resulted in similarity values of 33.9 and 22.0 %, respectively. DDH between RB56 and DSM44801 and DSM44290 showed similarity values of 20.7 and 22.3 %, respectively. In addition, wet-lab DDH between RB56 and JCM19832 resulted in 10.2 % (14.5 %) similarity. Both strains showed morphological and chemotaxonomic features typical for the genus , such as the presence of -diaminopimelic acid (Apm) within the cell wall, arabinose and galactose as major sugar components within whole cell-wall hydrolysates, the presence of mycolic acids and major phospholipids (diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol), and the predominant menaquinone MK-8 (H, ω-cyclo). The main fatty acids for both strains were hexadecanoic acid (C), 10-methyloctadecanoic acid (10-methyl C) and -9-octadecenoic acid (C ω9). We propose two novel species within the genus : sp. nov. with the type strain RB20 (=VKM Ac-2841=NRRL B65541) and sp. nov. with the type strain RB56 (=VKM Ac-2842=NRRL B65542).
Topics: Animals; Bacterial Typing Techniques; Base Composition; DNA, Bacterial; Diaminopimelic Acid; Fatty Acids; Gastrointestinal Microbiome; Isoptera; Nocardia; Phospholipids; Phylogeny; RNA, Ribosomal, 16S; South Africa; Vitamin K 2
PubMed: 32815801
DOI: 10.1099/ijsem.0.004398 -
Antimicrobial Agents and Chemotherapy Feb 2022species cause a broad spectrum of infections, especially in immunocompromised patients. Given its relative rarity, data on the prognosis and distribution of nocardiosis...
species cause a broad spectrum of infections, especially in immunocompromised patients. Given its relative rarity, data on the prognosis and distribution of nocardiosis from a large cohort are scarce. The present study aimed to scrutinize the clinical features and outcomes of nocardiosis in Japan, including 1-year mortality and microbiological data. The present multicentric, retrospective cohort study enrolled patients aged ≥18 years with nocardiosis diagnosed between January 2010 and December 2017 and recorded their clinical and microbiological characteristics. Factors associated with 1-year mortality were also determined using Cox proportional hazard analysis. In total, 317 patients were identified at 89 hospitals. Almost half (155/317, 48.9%) were receiving immunosuppressive agents, and 51 had disseminated nocardiosis (51/317, 16.1%). The 1-year all-cause mortality rate was 29.4% (80/272; lost to follow-up, = 45). The most frequently isolated species was Nocardia farcinica (79/317, 24.9%) followed by the Nocardia nova complex (61/317, 19.2%). Selected antimicrobial agents were generally effective, with linezolid (100% susceptibility [S]) and amikacin (94% S) having the most activity against species. In Cox proportional hazard analysis, factors independently associated with 1-year mortality were a Charlson comorbidity index score of ≥5 (adjusted hazard ratio [aHR], 3.61; 95% confidence interval [CI], 1.95 to 6.71, 0.001) and disseminated nocardiosis (aHR, 1.79; 95%CI, 1.01 to 3.18, 0.047). The presence of advanced comorbidities and disseminated infection, rather than variations in antimicrobial therapy or species, was independently associated with 1-year mortality.
Topics: Adolescent; Adult; Anti-Bacterial Agents; Cohort Studies; Humans; Japan; Nocardia; Nocardia Infections; Retrospective Studies
PubMed: 34902263
DOI: 10.1128/AAC.01890-21 -
Scientific Reports Aug 2021The aims of the present study were to profile the antimicrobial susceptibility patterns of a diverse range of Nocardia species isolated in Japan, and to determine the...
The aims of the present study were to profile the antimicrobial susceptibility patterns of a diverse range of Nocardia species isolated in Japan, and to determine the ability of matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) for species/complex identification. Identification of 153 clinical isolates was performed by full-length 16S rRNA gene sequencing as a reference method to evaluate the usefulness of MALDI-TOF MS identification. Antimicrobial susceptibility testing (AST) for 14 antibiotics was performed using the broth microdilution method against 146 of the isolates. Among the total 153 clinical isolates, Nocardia farcinica complex (25%) was the most common species, followed by Nocardia cyriacigeorgica (18%), Nocardia brasiliensis (9%), Nocardia nova (8%), and Nocardia otitidiscaviarum (7%). Among 150 isolates identified to the species/complex level by 16S rRNA gene sequencing, MALDI-TOF MS with the use of a supplemental Nocardia library (JMLD library ver.ML01) correctly identified 97.3% (n = 146) to the species/complex level and 1.3% (n = 2) to the genus level. Among the 146 Nocardia isolates that underwent AST, the susceptibilities were 100% to linezolid, 96% to amikacin, 94% to trimethoprim-sulfamethoxazole, and 76% to imipenem. None of the trimethoprim-sulfamethoxazole-resistant isolates carried either plasmid-mediated sulfonamide-resistant genes (sul1, sul2) or trimethoprim-resistant genes (dfrA).
Topics: Drug Resistance, Bacterial; Genes, Bacterial; Humans; Japan; Nocardia; Plasmids; RNA, Bacterial; RNA, Ribosomal, 16S
PubMed: 34408177
DOI: 10.1038/s41598-021-95870-2 -
JMM Case Reports Feb 2019complex has been associated with infections in both immunocompetent and immunocompromised patients. Infection can be localized or disseminated, affecting skin and soft...
INTRODUCTION
complex has been associated with infections in both immunocompetent and immunocompromised patients. Infection can be localized or disseminated, affecting skin and soft tissues, the respiratory system, bones and joints, the circulatory system and especially the central nervous system. Ocular infections such as keratitis, scleritis, conjunctivitis, dacryocystitis, orbital cellulitis and endophthalmitis due to spp. are infrequently reported, and usually described after penetrating corneal trauma or ocular contact with plants and soils.
CASE PRESENTATION
An immunocompetent male presented with a history of penetrating ocular trauma that had evolved to infectious endophthalmitis, which was refractory to different antibiotic treatments. No micro-organisms were isolated from repeated conjunctival smear and corneal scraping cultures between the ocular trauma (August 2014) and the endophthalmitis diagnosis (November 2015). After this period, was isolated in aqueous humour aspirate. Treatment was adjusted and clinical improvement was obtained after an adequate microbiological procedure, including an optimal sampling and an antimicrobial-susceptibility testing report.
CONCLUSION
identification to the species level and performance of antimicrobial-susceptibility tests are both essential tools for treatment adjustment and clinical improvement.
PubMed: 30886723
DOI: 10.1099/jmmcr.0.005175 -
Drug Discoveries & Therapeutics May 2021Nocardia is a ubiquitous environmental microbe that causes nocardiosis against immunosuppressed and immunocompromised hosts. The assay system for the quantitative... (Comparative Study)
Comparative Study
Nocardia is a ubiquitous environmental microbe that causes nocardiosis against immunosuppressed and immunocompromised hosts. The assay system for the quantitative evaluation of virulence of Nocardia sp. or therapeutic effectiveness of antimicrobials for treatment of nocardiosis is not established so far. In this study, we established an infection model of Nocardia sp. using silkworm as an alternative animal model. We found that all tested Nocardia sp. such as Nocardia asiatica, Nocardia elegans, Nocardia exalbida, Nocardia farcinica, and Nocardia nova killed silkworm and their killing ability were different by species. N. farcinica showed higher pathogenicity among tested strain, similar to the mouse model as previously reported. In addition, we found that antimicrobials such as amikacin and minocycline showed therapeutic effectiveness in silkworms infected with N. farcinica, and we could determine effective doses 50 (ED₅₀) values. These results suggest that silkworm is a useful alternative animal to evaluate the pathogenicity of Nocardia pathogen and the therapeutic effects of antimicrobials against Nocardia sp. in a quantitative manner.
Topics: Animals; Anti-Bacterial Agents; Bombyx; Dose-Response Relationship, Drug; Humans; Immunocompromised Host; Japan; Mice; Models, Animal; Nocardia; Nocardia Infections; Treatment Outcome; Virulence
PubMed: 33952779
DOI: 10.5582/ddt.2021.01035 -
Antimicrobial Agents and Chemotherapy Jul 2018spp. are Gram-positive opportunistic pathogens that affect largely immunocompromised patients, leading to serious pulmonary or systemic infections. Combination therapy...
spp. are Gram-positive opportunistic pathogens that affect largely immunocompromised patients, leading to serious pulmonary or systemic infections. Combination therapy using the folate biosynthesis pathway inhibitors trimethoprim (TMP) and sulfamethoxazole (SMX) is commonly used as an antimicrobial therapy. Not surprisingly, as antibiotic therapies for nocardiosis can extend for many months, resistance to TMP-SMX has emerged. Using experimental evolution, we surveyed the genetic basis of adaptation to TMP-SMX across 8 strains of and 2 strains of By employing both continuous experimental evolution to provide longitudinal information on the order of changes and characterization of resistant endpoint isolates, we observe changes that are consistent with modifications of two enzymes of the folate biosynthesis pathway: dihydrofolate reductase (DHFR) and dihydropteroate synthase (DHPS) (FolP), with the mutations often being clustered near the active site of the enzymes. While changes to DHFR and DHPS might be expected, we also noted that mutations in a previously undescribed homolog of DHPS (DHPS2 or FolP2) that was annotated as being "nonfunctional" were also sufficient to generate TMP-SMX resistance, which serves as a cautionary tale for the use of automated annotation by investigators and for the future discovery of drugs against this genus. Additionally, overlapped glucosyl-3-phosphoglycerate synthase. Remarkably, an adaptive frameshift mutation within the overlapping region resulted in a new in-frame fusion to the downstream gene to produce a potentially new bifunctional enzyme. How a single potentially bifunctional DHPS2 enzyme might confer resistance is unclear. However, it highlights the unexpected ways in which adaptive evolution finds novel solutions for selection.
Topics: Amino Acid Sequence; Anti-Bacterial Agents; Base Sequence; Dihydropteroate Synthase; Drug Resistance, Multiple, Bacterial; Frameshift Mutation; Glucosyltransferases; High-Throughput Nucleotide Sequencing; Humans; Longitudinal Studies; Microbial Sensitivity Tests; Nocardia; Nocardia Infections; Tetrahydrofolate Dehydrogenase; Trimethoprim Resistance; Trimethoprim, Sulfamethoxazole Drug Combination
PubMed: 29686152
DOI: 10.1128/AAC.00364-18 -
BMC Infectious Diseases Feb 2023Disseminated nocardiosis is a very rare disease. By now only few cases of meningitis and spondylodiscitis have been reported. To our knowledge, this is the first case of...
BACKGROUND
Disseminated nocardiosis is a very rare disease. By now only few cases of meningitis and spondylodiscitis have been reported. To our knowledge, this is the first case of meningitis caused by Nocardia nova.
CASE PRESENTATION
We report on a case of bacteraemia, meningitis and spondylodiscitis caused by N. nova in an immunocompetent patient. We describe the long, difficult path to diagnosis, which took two months, including all diagnostic pitfalls. After nocardiosis was diagnosed, intravenous antibiotic therapy with ceftriaxone, later switched to imipenem/cilastatin and amikacin, led to rapid clinical improvement. Intravenous therapy was followed by oral consolidation with co-trimoxazole for 9 months without any relapse within 4 years.
CONCLUSIONS
Establishing a diagnosis of nocardiosis is a precondition for successful antibiotic therapy. This requires close communication between clinicians and laboratory staff about the suspicion of nocardiosis, than leading to prolonged cultures and specific laboratory methods, e.g. identification by 16S rDNA PCR.
Topics: Humans; Discitis; Nocardia; Nocardia Infections; Anti-Bacterial Agents; Meningitis
PubMed: 36823551
DOI: 10.1186/s12879-023-08067-5 -
A case report on mixed pulmonary infection of , and based on metagenomic next-generation sequencing.Frontiers in Public Health 2022Pulmonary infection is one of the common complications of long-term use of glucocorticoids. Severe infections not only increase the length of hospital stay and treatment...
BACKGROUND
Pulmonary infection is one of the common complications of long-term use of glucocorticoids. Severe infections not only increase the length of hospital stay and treatment costs but also cause progression or recurrence of the primary disease.
CASE DESCRIPTION
Herein, we reported a case of mixed pulmonary infection secondary to glucocorticoid use. Rare pathogens such as , and cytomegalovirus were detected by metagenomic next-generation sequencing (mNGS) of bronchoalveolar lavage fluid and lung puncture tissue. Combining the results of conventional pathogen detection and clinical symptoms, the patient was diagnosed with mixed pulmonary infection by multiple pathogens. After timely targeted medication, the patient was finally discharged with a good prognosis.
CONCLUSION
To our knowledge, this is the first case report on mixed pulmonary infection with pathogens including , and human cytomegalovirus. As a new clinical diagnostic method, mNGS has great advantages in diagnosis of diseases such as mixed infections.
Topics: Aspergillus fumigatus; Coinfection; Glucocorticoids; High-Throughput Nucleotide Sequencing; Humans; Lung; Mycobacterium tuberculosis; Nocardia; Pneumonia
PubMed: 36148364
DOI: 10.3389/fpubh.2022.927338 -
Revista Chilena de Infectologia :... Jun 2020Nocardiosis is a localized or systemic infection that mainly affects immunocompromised patients, with pulmonary localization being the most frequent site. The...
Nocardiosis is a localized or systemic infection that mainly affects immunocompromised patients, with pulmonary localization being the most frequent site. The transmission comes mainly from the inhalation of spores or by direct inoculation into the skin and ocular mucosa. More than 90 species of nocardia are described, of which more than half are recognized as pathogens in humans. The best known species of medical importance are Nocardia farcinica, Nocardia abscessus, Nocardia nova y Nocardia brasiliensis. In Chile, there have been published cases of Nocardia asteroides and Nocardia farcinica infections. Nocardia cyriacigeorgica is considered an emerging species, there being no cases previously described in our country. We present a clinical case of pulmonary nocardiosis in an acquired immunodeficiency syndrome (AIDS) patient.
Topics: Acquired Immunodeficiency Syndrome; Chile; Humans; Nocardia; Nocardia Infections
PubMed: 32853327
DOI: 10.4067/s0716-10182020000300322