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Microbiology Spectrum Apr 2022The genus Nocardia includes ubiquitous environmental saprophytes and the most frequently isolated aerobic actinomycete human pathogen responsible for localized or...
The genus Nocardia includes ubiquitous environmental saprophytes and the most frequently isolated aerobic actinomycete human pathogen responsible for localized or disseminated infection. Herein, the species distribution and antimicrobial susceptibility profiles of 441 nonrepetitive Nocardia strains are reported, collected from 21 provinces/cities in China over 13 years (from 2009 to 2021). These isolates were identified to species level by mass spectrometry or targeted DNA sequencing. The susceptibility profiles of Nocardia species for 15 antibiotics were determined by the broth microdilution method. Among these Nocardia isolates, Nocardia farcinica was the most commonly isolated species (39.9%, 176 of 441), followed by Nocardia cyriacigeorgica (28.6%, 126), Nocardia abscessus (6.6%, 29), and Nocardia otitidiscaviarum (5.9%, 26). Furthermore, 361 Nocardia strains (81.9%) were collected from lower respiratory tract (sputum, lung tissue, and bronchoalveolar lavage fluid), 50 (11.3%) were collected from skin and soft tissues, 9 were collected from blood, 9 were collected from eye, 4 were collected from cerebrospinal fluid and brain abscesses, and 2 were collected from pleural effusion. All of the Nocardia strains were susceptible to linezolid, followed by amikacin (99.3%) and trimethoprim-sulfamethoxazole (TMP-SMX) (99.1%). The antibiotic resistance profiles of other antibiotics varied tremendously among different Nocardia species. This demonstrated that accurate species identification and/or antibiotic susceptibility testing should be performed before the usage of these antibiotics. In summary, this is the largest study on the species and antibiotic resistance profiles of the genus Nocardia circulating in China, and our data will contribute to a better understanding of clinical nocardiosis. The genus Nocardia has the potential to cause nocardiosis, which might be underrecognized and underdiagnosed. Herein, the demographical features of 441 nonrepetitive nocardiosis cases and species distribution of their Nocardia strains in China, 2009 to 2021, are summarized. The susceptibility profiles for 15 antibiotics against all of the above Nocardia strains were also determined by the broth microdilution method. To date, this is the largest study on the genus Nocardia contributing to nocardiosis in China. Our study will be helpful for understanding the species diversity of Nocardia isolates distributed in China and for decision-making in the context of nocardiosis diagnosis and treatment.
Topics: Anti-Bacterial Agents; Base Sequence; Drug Resistance, Bacterial; Humans; Nocardia; Nocardia Infections
PubMed: 35234511
DOI: 10.1128/spectrum.01560-21 -
Ear, Nose, & Throat Journal Dec 2022Nocardia is regarded as an opportunistic pathogen primarily affecting the respiratory system, whereas is the species of the Nocardia family that is most frequently...
Nocardia is regarded as an opportunistic pathogen primarily affecting the respiratory system, whereas is the species of the Nocardia family that is most frequently blamed for central nervous system impairment. The authors present the first case of mastoiditis caused by , accompanied by intracranial complications. An immunocompetent 74-year-old woman who reported a three-week left ear discharge and a two-week facial nerve palsy was referred to our department. MRI revealed mastoiditis and epidural abscess. The bacterial cultures obtained during the surgical management of the patient confirmed the presence of . Targeted antibiotic therapy was subsequently administrated, gradually resulting in favourable outcomes. Nocardia species provoke a disseminated infection that emerges not only among the immunosuppressed individuals but can also affect the healthy population. The nonspecific clinical manifestations in addition to the difficulties identifying the pathogen, remain obstacles to a punctual diagnosis. However, the combination of surgical debridement and antibiotic treatment with trimethoprim and sulfamethoxazole is considered the most appropriate management, leading to propitious results.
PubMed: 36453208
DOI: 10.1177/01455613221139400 -
Ear, Nose, & Throat Journal Mar 2023usually infects people with impaired immune status and usually manifests in the lungs. Otomastoiditis caused by Nocardia infection is extremely rare, with only 4 cases...
usually infects people with impaired immune status and usually manifests in the lungs. Otomastoiditis caused by Nocardia infection is extremely rare, with only 4 cases reported to date. This report describes a case of otomastoid infection in an immunocompetent patient. The case was a 10-month-old immunocompetent infant who presented with an approximately 3-month history of right ear discharge for which treatment with various antibiotics had not resulted in significant improvement. Multiple cultures of secretions and pathologic examination failed to identify the causative organism. The patient then underwent right mastoidectomy. Finally, metagenomic next-generation sequencing identified the pathogen to be . The patient was infection-free at the 6-month follow-up but had developed labyrinthitis ossificans. Otomastoid Nocardia infection has characteristic clinical features, namely, formation of a large amount of granulation tissue and coexistence of bone destruction and new bone formation. Traditionally, Nocardia is challenging to diagnose. Metagenomic next-generation sequencing of lesions is helpful. Complete local debridement and free drainage are key to treatment.
PubMed: 36941739
DOI: 10.1177/01455613231165166 -
Frontiers in Immunology 2022Males are generally more susceptible to infection than females, with a male-to-female ratio of 2 and higher clinical disease. 17β-Estradiol has been implicated in...
Males are generally more susceptible to infection than females, with a male-to-female ratio of 2 and higher clinical disease. 17β-Estradiol has been implicated in affecting the sex-based gap by inhibiting the growth of in experiments, but the underlying mechanisms have not yet been fully clarified. In the present study, however, we report increased severity in IFM 10152-infected female mice compared with male mice with increased mortality, elevated lung bacterial loads and an exaggerated pulmonary inflammatory response, which was mimicked in ovariectomized female mice supplemented with E2. Similarly, the overwhelming increase in bacterial loads was also evident in E2-treated host cells, which were associated with downregulating the phosphorylation level of the MAPK pathway by binding the estrogen receptor. We conclude that although there are more clinical cases of infection in males, estrogen promotes the survival of the bacteria, which leads to aggravated inflammation in females. Our data emphasize the need to include and separately analyze both sexes in future studies of to understand the sex differences in immune responses and disease pathogenesis.
Topics: Animals; Estradiol; Estrogens; Female; Male; Mice; Nocardia; Nocardia Infections
PubMed: 35309304
DOI: 10.3389/fimmu.2022.858609 -
Journal of Neurosurgery. Case Lessons Oct 2022Pituitary abscess is a rare clinical entity, typically precipitated by Staphylococcus, Pseudomonas, or Aspergillus infection. Although Nocardia species-associated...
BACKGROUND
Pituitary abscess is a rare clinical entity, typically precipitated by Staphylococcus, Pseudomonas, or Aspergillus infection. Although Nocardia species-associated central nervous system abscesses have been documented in immunocompromised patients, no case of Nocardia pituitary abscesses has been previously reported.
OBSERVATIONS
A 44-year-old man presented with hemoptysis and was found to have a cavitary right lung nodule, which was presumed histoplasmosis, prompting antifungal treatment. Several months later, he developed panhypopituitarism. Magnetic resonance imaging identified a pituitary mass, which subsequently underwent transsphenoidal endoscopic biopsy. Infectious workup was negative, and the patient was discharged on intravenous ertapenem therapy. Over several months, he developed progressive headaches, and updated imaging confirmed interval enlargement of the mass with new cavernous sinus invasion. He underwent repeat endoscopic biopsy, which yielded positive cultures for Nocardia farcinica and prompted successful treatment with trimethoprim-sulfamethoxazole and linezolid.
LESSONS
The current study highlights a previously unreported clinical entity, the first pituitary abscess attributable to Nocardia sp. or N. farcinica, which arose in a young, immunocompetent individual. Although rare, atypical infections represent an important component in the differential diagnosis for sellar mass lesions.
PubMed: 36317239
DOI: 10.3171/CASE22266 -
IDCases 2022An 84-year-old female with severe liver cirrhosis due to hepatitis C presented with a progressive bulging of the anterior chest wall for two weeks. On examination, 7 cm...
An 84-year-old female with severe liver cirrhosis due to hepatitis C presented with a progressive bulging of the anterior chest wall for two weeks. On examination, 7 cm × 7 cm × 5 cm large subcutaneous mass was on the anterior chest wall and contrast enhanced computed tomography of the chest demonstrated loculated empyema with extension through the chest wall, into the anterior with rib destruction. Microscopic appearance of the abscess revealed filamentous branching rods, and eventually Nocardia farcinica was identified using Matrix-Assisted Laser Desorption Ionization-Time of Flight. The patient was successfully treated with trimethoprim/sulfamethoxazole and subcutaneous debridement. In general, Mycobacterium tuberculosis and Actinomyces spp. are the most common causative pathogens of empyema necessitans, and cases of Nocardia spp. are rarely seen. Clinicians should pay attention to the possibility of nocardial empyema necessitans in immunocompromised patients.
PubMed: 35795529
DOI: 10.1016/j.idcr.2022.e01545 -
The New Microbiologica Feb 2023In this paper, we have described cases of nocardiosis that occurred in our hospital and examined the literature on other nocardiosis cases recorded in Italy. We have... (Review)
Review
In this paper, we have described cases of nocardiosis that occurred in our hospital and examined the literature on other nocardiosis cases recorded in Italy. We have collected the clinical details of our recent cases and described them in full. Regarding the older cases in our hospital and the Italian cases present in the literature, we noted the clinical data, the Nocardia species involved, and the antimicrobial susceptibility reported. The survey was carried out on PubMed. The first of our cases is an elderly woman with compromised health who had a lung and bloodstream infection. A second case is a middle-aged man who developed an infection in the thigh. A third patient is a middle-aged man on immunosuppressive therapy who developed a cerebral abscess. Our review shows that patients are usually immunocompromised, with an average age of 60 years, and more frequently males. The most affected organs are the lungs and the brain, and the most reported species is Nocardia farcinica. Antimicrobial susceptibility tests show good efficacy of linezolid, cotrimoxazole and amikacin. We conclude that, if a Nocardia infection is suspected, the most likely species to be considered in Italy is N. farcinica. In addition, if empirical therapy is needed, we suggest relying on linezolid, cotrimoxazole or amikacin.
Topics: Aged; Male; Middle Aged; Female; Humans; Amikacin; Linezolid; Trimethoprim, Sulfamethoxazole Drug Combination; Nocardia Infections; Italy; Anti-Infective Agents
PubMed: 36853822
DOI: No ID Found -
Journal of Ophthalmic Inflammation and... Jun 2021A case report of post-traumatic exogenous endophthalmitis caused by Nocardia farcinica, including treatment procedures, microbiology examination, and systemic...
A case report of post-traumatic exogenous endophthalmitis caused by Nocardia farcinica, including treatment procedures, microbiology examination, and systemic medications. A 23-year-old male suffered a penetrating corneal injury that was treated with sutures. On the thirteenth day after the final suture was removed, an anterior uveitis developed and progressed to whitish, plump, nodular, and tufted exudates within the anterior chamber over the next 10 days; this led to an indication for intraocular surgery. Anterior chamber lavage and resection of solid fibrinous exudates (using a vitrectomy knife) for a complete microbiological examination were performed. Nocardia farcinica was identified. Systemic medications were chosen according to sensitivity, and a fixed combination of sulfamethoxazole 400 mg/trimethoprim 80 mg was administered long-term (months). In this case, accurate, early detection of an atypical infectious agent and determination of its sensitivity to antibiotic treatment enabled effective treatment that achieved the best functional and anatomical results under the circumstances.
PubMed: 34059965
DOI: 10.1186/s12348-021-00245-3 -
Journal of Medical Microbiology Dec 2020Accurate identification of species remains a challenge due to the complexities of taxonomy and insufficient discriminatory power of traditional techniques. We report...
Accurate identification of species remains a challenge due to the complexities of taxonomy and insufficient discriminatory power of traditional techniques. We report the development of a molecular technique that utilizes real-time PCR-based high-resolution melting (HRM) analysis for differentiation of the most common species. Based on a novel intergenic region sequence, , and were clearly distinguished from one another by HRM analysis. The limit of detection of the HRM assay for purified spp. DNA was at least 10 fg. No false positives were observed for specificity testing of 20 non-target clinical samples. In comparison to established matrix-assisted laser desorption/ionization-time of flight MS, the HRM assay improved the identification of . Additionally, all the products of PCR were verified by direct sequencing. In conclusion, the developed molecular assay allows simultaneous detection and differentiation of , and with high sensitivity and specificity.
Topics: DNA, Bacterial; Genetic Loci; Molecular Typing; Nocardia; Nucleic Acid Denaturation; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
PubMed: 32478652
DOI: 10.1099/jmm.0.001205 -
Frontiers in Medicine 2022Brain abscesses caused by are rare and difficult to diagnose. Conventional methods for diagnosing Nocardia species include blood culture, microscopy, and tissue slice,...
BACKGROUND
Brain abscesses caused by are rare and difficult to diagnose. Conventional methods for diagnosing Nocardia species include blood culture, microscopy, and tissue slice, but the performance is not satisfied. We report a case of brain abscess due to diagnosed by metagenomic next-generation sequencing (mNGS).
CASE PRESENTATION
We report a case of a 58-year-old man with brain abscess caused by . The patient had a history of pemphigus and required long-term methylprednisolone administration. No pathogen was detected in blood culture, cerebrospinal fluid (CSF) culture, and fast-acid staining. mNGS identified in the CSF. The symptoms and signs of the patient were significantly improved after changing the antibiotics accordingly to sensitive antibiotics.
CONCLUSION
Metagenomic next-generation sequencing (mNGS) is helpful for early diagnosis and subsequent treatment of -associated meningitis and encephalitis, avoiding brain surgery. Early and accurate diagnosis and prompt antibiotic treatment reduced its mortality.
PubMed: 35252247
DOI: 10.3389/fmed.2022.803554