Central nervous system nocardiosis in a 54-year-old man with lateral ventricular choroid plexitis and diffused meningitis: A case report.

INTRODUCTION: Nocardiosis is an unusual infection caused by aerobic gram-positive bacteria in the genus Nocardia. Infections resulting from Nocardia species are frequent in immunosuppressive patients. Weakened immune systems caused by human immunodeficiency virus infection, diabetes, cancer, and other conditions such as chronic lung disease, renal failure, etc, are the main risk factors for nocardiosis. Central nervous system (CNS) nocardiosis has been reported to represent ~2% of all and to be present in 15% to 50% of patients with systemic infection. The patient in our case had an isolated CNS nocardiosis caused by Nocardia terpenica infection, a rare reclassified Nocardia pathogen of CNS nocardiosis. CASE: We here present a 54-year-old Chinese male with a fever and headache for 15 days who showed positive meningeal irritation signs. Magnetic resonance imaging showed the right trigone of the lateral ventricular choroid plexitis and diffused leptomeningeal meningitis involving the bilateral cerebral hemisphere, cerebellar hemisphere, and brain stem. The patient was quickly diagnosed with CNS Nocardia infection by next-generation sequencing within 48 hours after admission. Meanwhile, the diagnosis was validated by Nocardia-positive staining in cerebral spinal fluid culturing. The patient was given trimethoprim-sulfamethoxazole, and his symptoms recovered after 3 days. CONCLUSIONS: In this case, the clinical, radiological, and microbiological findings highlight the importance of suspecting Nocardia as the potential pathogen in patients with central nervous system inflammation of doubted immune incompetence. In addition, next-generation sequencing as an effective test is also highly recommended for suspicious CNS infection patients to perform a rapid diagnosis and treatment.

A Presentation of Disseminated Nocardia Paucivorans Infection: A Case Report.

Nocardia paucivorans is a rarely cultured bacteria most commonly found in immunocompromised hosts, and rarely, may result in dissemination across multiple organ systems. Infection and subsequent clinical manifestations are often vague and nonspecific, making timely diagnosis difficult. Due to the infrequency of N. paucivorans infection, no consensus treatment has yet been established. We report a case of an immunocompromised patient with disseminated nocardiosis with infective endocarditis and other extrapulmonary involvement.

Multiple brain abscesses caused by Nocardia farcinica infection after hand injury: A case report and literature review.

RATIONALE: Nocardia infection is commonly regarded as an opportunistic pulmonary pathogen affecting debilitated or immunocompromised individuals. Brain abscesses caused by Nocardia farcinica are rare and pose a diagnostic challenge. Traditional diagnostic techniques for identifying Nocardia species, such as blood culture, microscopy, and pathology, have shown inadequate performance. In the reported case, we applied metagenomic next-generation sequencing (mNGS) to diagnose a case of brain abscess due to N. farcinica. PATIENT CONCERNS: A 66-year-old female developed a brain abscess after sustaining a hand injury. The patient exhibited a gradual change in personality and experienced tremors in her right upper limb for a duration of 1 month. DIAGNOSES: The pathogen responsible for the multiple brain abscesses was identified in the cerebrospinal fluid as N. farcinica through mNGS. INTERVENTIONS: Antibiotic treatment included trimethoprim-sulfamethoxazole, linezolid, amikacin, meropenem, and moxifloxacin. OUTCOMES: The patient's symptoms and signs improved significantly after administration of antibiotics to which the pathogen is known to be sensitive. After 5 months of follow-up, magnetic resonance imaging of the head showed that the abscess was basically cured. The patient lived a normal life with no adverse drug reactions. LESSONS: Nocardia brain infection is characterized by an insidious onset and lacks distinctive clinical and imaging features. mNGS was advantageous for the timely identification and management of Nocardia-associated brain abscess in the present case and obviated the need for invasive brain surgery. Expeditious and precise diagnosis coupled with prompt antibiotic therapy can significantly reduce the mortality rate associated with this condition.

Extensive mycetoma in forearm, chest and neck due to Nocardia mexicana.

INTRODUCTION: Mycetoma is a chronic granulomatous inflammatory disease of the subcutaneous tissue, which affects deep structures and bone. Most cases of actinomycetoma are caused by members of the genus Nocardia. CASE PRESENTATION: Here we report the case of a 43-year-old male who presented a disseminated mycetoma on the forearm, chest and neck, characterized by enlarged and erythematous lesions through which seropurulent material drains, and numerous atrophic scars. Molecular identification was performed by 16S gene amplification and sequencing. Nocardia mexicana was identified with 100% identity. Trimethoprim-sulfamethoxazole, diaminodiphenyl sulfone and amikacin was a successful treatment after 6 months. CONCLUSIONS: Nocardia mexicana is a rare organism that causes mycetoma. We report a case of extensive mycetoma on the forearm with spread to the neck and thorax associated with manipulation of the mouth of a calf.

[Systemic disseminated nocardiosis in a patient with normal immune function: a case report].

Nocardiosis, characterized by poor prognosis and high mortality, is a local or systemic suppurative or granulomatous disease caused by Nocardia that is common in immunosuppressed individuals but rare in populations with normal immune function. This paper described one case of Nocardia gipuzkoensis disseminated infection in a patient with normal immune function by outlining the process of treatment, conducting literature review and by outlining the clinical characteristics, diagnostic criteria and standardized treatments of nocardia disease, in the hope of providing reference for subsequent treatment of rare Nocardia subspecies infections.

Antibacterial activity of Nocardia spp. and Streptomyces sp. on multidrug-resistant pathogens causing neonatal sepsis.

Neonatal sepsis leads to severe morbidity and occasionally death among neonates within the first week following birth, particularly in low- and middle-income countries. Empirical therapy includes antibiotics recommended by WHO. However, these have been ineffective against antimicrobial multidrug-resistant bacterial strains such as Klebsiella spp, Escherichia coli, and Staphylococcus aureus species. To counter this problem, new molecules and alternative sources of compounds with antibacterial activity are sought as options. Actinobacteria, particularly pathogenic strains, have revealed a biotechnological potential still underexplored. This study aimed to determine the presence of biosynthetic gene clusters and the antimicrobial activity of actinobacterial strains isolated from clinical cases against multidrug-resistant bacteria implicated in neonatal sepsis. In total, 15 strains isolated from clinical cases of actinomycetoma were used. PCR screening for the PKS-I, PKS-II, NRPS-I, and NRPS-II biosynthetic systems determined their secondary metabolite-producing potential. The strains were subsequently assayed for antimicrobial activity by the perpendicular cross streak method against Escherichia fergusonii Sec 23, Klebsiella pneumoniae subsp. pneumoniae H1064, Klebsiella variicola H776, Klebsiella oxytoca H793, and Klebsiella pneumoniae subsp. ozaenae H7595, previously classified as multidrug-resistant. Finally, the strains were identified by 16S rRNA gene sequence analysis. It was found that 100% of the actinobacteria had biosynthetic systems. The most frequent biosynthetic system was NRPS-I (100%), and the most frequent combination was NRPS-I and PKS-II (27%). All 15 strains showed antimicrobial activity. The strain with the highest antimicrobial activity was Streptomyces albus 94.1572, as it inhibited the growth of the five multidrug-resistant bacteria evaluated.

Weathering the storm: diagnosis and treatment of a life-threatening disseminated Nocardia otitidiscaviarum infection.

Nocardiosis demonstrates a temporal categorization that includes acute, subacute, and chronic stages alongside distinct typical localizations such as pulmonary, cutaneous, and disseminated forms. Disseminated nocardiosis, commonly caused by Nocardia asteroides, N. brasiliensis, and N. farcinica, continues to result in substantial morbidity and mortality. Herein, we report a life-threatening disseminated nocardiosis caused by Nocardia otitidiscaviarum in a patient with minimal change disease. This study emphasizes the difficulty in the diagnosis and treatment of unknown infections in clinical settings and highlights the important role played by laboratories in solving infectious diseases caused by rare pathogens.

Nocardia implantans sp. nov. isolated from a patient with pulmonary infection.

TwoGram-stain-positive and rod-shaped actinomycetes (strains CDC186T and CDC192) were isolated from sputum samples of a patient in Chongqing, PR China, and were investigated to determine their taxonomic status. The results of phylogenetic analysis based on the 16S rRNA gene indicated that CDC186T and CDC192 represented members of the genus Nocardia, and the sequence similarity with Nocardia beijingensis DSM 44636T was the highest, at 99.71 and 99.78 %, respectively. The DNA G+C content of both CDC186T and CDC192 was 69.1 %. Genomic diversity analysis revealed that the average nucleotide identity and in silico DNA‒DNA hybridisation values between the two novel strains and closely related species were significantly below the thresholds of 95-96 and 70 %, respectively, but these values between the two novel strains were 99.96 and 99.90 %, respectively. The phylogenetic relationship based on the dapb1 gene and the single-copy core genes further indicated that the two novel strains were clustered in separate branch adjacent to N. beijingensis DSM 44636T. Growth occurred within the ranges of 20-42 °C, pH 6.0-9.0 and NaCl concentrations of 0.5-4.5 % (w/v). The major fatty acids of CDC186T and CDC192 were C16 : 0 and C18 : 0 10-methyl [tuberculostearic acid (TBSA)]. The predominant respiratory menaquinone was MK-9. The polar lipid profile contained diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol mannoside, one unidentified glycolipid, one unidentified phospholipid and one unidentified phosphoglycolipid. All the genomes of the studied strains were annotated with virulence factor (VF)-associated genes homologous to those of Mycobacterium tuberculosis, and the results of susceptibility testing indicated that CDC186T and CDC192 were resistant to amoxicillin-clavulanic acid and tigecycline. On the basis of chemotaxonomic characteristics and the results of phylogenetic analyses, strains CDC186T and CDC192 represent a novel species within the genus Nocardia, for which the name Nocardia implantans sp. nov. is proposed. The type strain is CDC186T (=GDMCC 4.206T= JCM 34959T).

Nocardia brasiliensis Pyomyositis in an Immunocompetent Patient Following Gardening Activity.

Nocardia pyomyositis in immunocompetent patients is a rare occurrence. The diagnosis may be missed or delayed with the risk of progressive infection and suboptimal or inappropriate treatment. We present the case of a 48-year-old immunocompetent firefighter diagnosed with pyomyositis caused by Nocardia brasiliensis acquired by direct skin inoculation from gardening activity. The patient developed a painful swelling on his right forearm that rapidly progressed proximally and deeper into the underlying muscle layer. Ultrasound imaging of his right forearm showed a 7-mm subcutaneous fluid collection with surrounding edema. Microbiologic analysis of the draining pus was confirmed to be N brasiliensis by Matrix-Assisted Laser Desorption/Ionization Time-of-Flight (MALDI-TOF) Mass Spectrometry. After incision and drainage deep to the muscle layer to evacuate the abscess and a few ineffective antibiotic options, the patient was treated with intravenous ceftriaxone and oral linezolid for 6 weeks. He was then de-escalated to oral moxifloxacin for an additional 4 months to complete a total antibiotic treatment duration of 6 months. The wound healed satisfactorily and was completely closed by the fourth month of antibiotic therapy. Six months after discontinuation of antibiotics, the patient continued to do well with complete resolution of the infection. In this article, we discussed the risk factors for Nocardia in immunocompetent settings, the occupational risks for Nocardia in our index patient, and the challenges encountered with diagnosis and treatment. Nocardia should be included in the differential diagnosis of cutaneous infections, particularly if there is no improvement of "cellulitis" with traditional antimicrobial regimens and the infection extends into the deeper muscle tissues.

Fatal Nocardia paucivorans Lower Respiratory Tract Infection in a Tuberculosis Suspect Who Worked as Gold Miner.

Nocardiosis is an opportunistic infection that affects both immunocompromised as well as immunocompetent patients. The main infections occur as soft tissue and lung infections although they might disseminate to various organs. This is a case study aimed to reflect the severity of the disease and the patient's risk factors associated with the infection. A sputum sample was collected from tuberculosis (TB) suspects for culture. Nocardia-like colonies were isolated, purified, and sent to BGI Company (Hongkong, China). Standard forward sequencing of 16S rRNA was done by ABI Genetic Analyzer (Applied Biosystems). Sequence alignment and nucleotide basic local alignment search tool (BLAST) were done using National Center for Bioinformatics (NCBI) Nucleotide BLAST. Biochemical identification to the colonies was done using an automation system (BD Phoenix™) to confirm the identification. Nocardia paucivorans was identified from the TB suspect. Risk factors were identified as extensive contact to dust, absence of primary care units with complete facilities, and old age. Since the infection of the lungs caused by Nocardia might be similar to pulmonary TB, this case report highlights the importance of accurate diagnosis and identification procedures to differentiate between the two.

Disseminated nocardiosis presenting as a superinfected thyroglossal duct cyst in a patient with diabetes.

We introduce the case of a male patient in his 60s who was admitted to our emergency department with a persisting sore throat for the last 3 weeks and dysphagia. Fibre-endoscopic evaluation revealed an asymmetry at the base of the tongue. In combination with elevated white cell count and C reactive protein, a computerized tomography showed a superinfected thyroglossal duct cyst. Intravenous antibiotics were initiated, and the patient was taken to the operating room for cervicotomy. The microbiological swab taken intraoperatively detected Nocardia paucivorans Additional imaging revealed disseminated nocardiosis with cerebral and pulmonary manifestations.The patient was treated with oral trimethoprim/sulfamethoxazole and, over time, showed complete remission of central nervous system lesions and improvement of pulmonary involvement. Following this, the treatment was stopped 8 months after the initial diagnosis. In this report, we discuss treatment standards and outcomes of nocardiosis based on our management strategies of our patient.

Fever of unknown origin revealing testicular nocardiosis: a case report and literature review.

BACKGROUND: Nocardia is an ubiquitous soil organism. As an opportunistic pathogen, inhalation and skin inoculation are the most common routes of infection. Lungs and skin are the most frequent sites of nocardiosis. Testis is a highly unusual location for nocardiosis. CASE PRESENTATION: We report the case of an immunocompromised 75-year-old-man admitted for fever of unknown origin. He presented with skin lesions after gardening and was first suspected of Mediterranean spotted fever, but he did not respond to doxycycline. Then, physical examination revealed new left scrotal swelling that was compatible with a diagnosis of epididymo-orchitis. The patient's condition did not improve despite empirical antibiotic treatment with the onset of necrotic scrotal abscesses requiring surgery. Nocardia brasiliensis yielded from the removed testis culture. High-dose trimethoprim-sulfamethoxazole and ceftriaxone were started. Multiple micro-abscesses were found in the brain and spinal cord on imaging studies. After 6 weeks of dual antibiotic therapy for disseminated nocardiosis, slight regression of the brain abscesses was observed. The patient was discharged after a 6-month course of antibiotics and remained relapse-free at that time of writing these lines. Trimethoprim-sulfamethoxazole alone is meant to be pursued for 6 months thereafter. We undertook a literature review on previously reported cases of genitourinary and urological nocardiosis; to date, only 36 cases have been published with predominately involvement of kidney, prostate and testis. CONCLUSIONS: To the best of our knowledge, this is the first case of Nocardia brasiliensis simultaneously infecting skin, testis, brain and spinal cord in an immunocompromised patient. Knowledge on uncommon forms of nocardiosis remains scarce. This case report highlights the difficulty of diagnosing atypical nocardiosis and the importance of prompt bacteriological sampling in case of empirical antibiotics failure.

Disseminated nocardiosis caused by Nocardia otitidiscaviarum-A case report.

In this article we report a case of disseminated nocardiosis caused by Nocardia otitidiscaviarum in an immunocompetent patient with chronic obstructive pulmonary disease (COPD) who complained of a cough, followed by skin and intracranial lesions. On metagenomic next-generation sequencing (mNGS) technology of respiratory samples (bronchoalveolar lavage fluid, BALF) Nocardia otitidiscaviarum was identified. The patient was treated with therapy combined with a low dose of TMP-SMX and imipenem cilastatin sodium and had a favorable outcome. The timely diagnosis of Nocardia with the help of mNGS technology and early rational treatment of TMP-SMX can help improve the prognosis.

Comparison of clinical outcomes of pulmonary nocardiosis between AIDS and non-AIDS patients.

BACKGROUND: Nocardia species can affect both immunocompetent and immunocompromised people. METHOD: This retrospective study, from 2009 to 2022, aims to compare the survival analyses of pulmonary nocardiosis in AIDS and non-AIDS patients in northeastern Thailand. RESULTS: A total of 215 culture-confirmed cases of pulmonary nocardiosis: 97 with AIDS and 118 without AIDS. The median CD4 count of AIDS patients was 11 cells/µL (range: 1-198), and 33% had concurrent opportunistic infections. 63.6% of 118 non-AIDS patients received immunosuppressive medications, 28.8% had comorbidities, and 7.6% had no coexisting conditions. Disseminated nocardiosis and pleural effusion were more prevalent among AIDS patients, whereas non-AIDS patients revealed more shock and respiratory failure. One hundred-fifty patients underwent brain imaging; 15 (10%) had brain abscesses. Patients with pulmonary nocardiosis have overall 30-day and 1-year mortality rates of 38.5% (95% CI: 32.3%, 45.4%) and 52.1% (95% CI: 45.6%, 58.9%), respectively. The Cox survival analysis showed that AIDS patients with disseminated nocardiosis had a 7.93-fold (95% CI: 2.61-24.02, p < 0.001) increased risk of death within 30 days compared to non-AIDS patients when considering variables such as age, Charlson comorbidity index, concurrent opportunistic infections, duration of illness, shock, respiratory failure, multi-lobar pneumonia, lung abscesses, and combination antibiotic therapy. While AIDS and pulmonary nocardiosis had a tendency to die within 30 days (2.09 (95% CI, 0.74-5.87, p = 0.162)). CONCLUSION: AIDS with pulmonary nocardiosis, particularly disseminated disease, is a serious opportunistic infection. Early diagnosis and empiric treatment with a multidrug regimen may be the most appropriate approach in a resource-limited setting.

Biodegradation and antimicrobial capability-induced heavy metal resistance of the marine-derived actinomycetes Nocardia harenae JJB5 and Amycolatopsis marina JJB11.

Currently, heavy metal-resistant (HMR) marine actinomycetes have attracted much attention worldwide due to their unique capabilities. In this study, 27 marine-derived actinomycetes were isolated from coastal beaches in the Arabian Gulf of Al-Jubail in Saudi Arabia and screened for resistance to 100 mg/L of the heavy metals Cd2+, Cr6+, Cu2+, Fe2+, Pb2+, and Ni2+ using different assay techniques. Six isolates were selected as HMRs, of which two isolates, JJB5 and JJB11, exhibited the highest maximum tolerance concentrations (200- > 300 mg/L). Both isolates were the highest among six-HMR screened for their biodegradation potential of plastics low-density polyethylene, polystyrene, and polyvinyl chloride, recording the highest weight loss (15 ± 1.22 - 65 ± 1.2%) in their thin films. They also showed the highest biodegradability of the pesticides acetamiprid, chlordane, hexachlorocyclohexane, indoxacarb and lindane, indicating promising removal capacities (95.70-100%) for acetamiprid and indoxacarb using HPLC analysis. Additionally, the cell-free filtrate (CFF) of both isolates displayed the highest antimicrobial activity among the six-HMR screened against a variety of microbial test strains, recording the highest inhibition zone diameters (13.76 ± 0.66 - 26.0 ± 1.13 mm). GC‒MS analyses of the ethyl acetate extract of their CFFs revealed the presence of diverse chemical compounds with a multitude of remarkable biological activities. Based on their spore morphology and wall-chemotype, they were assigned to the nocardioform-actinomycetes. Furthermore, their phenotypic characteristics, together with 16S rRNA gene sequencing (OR121525-OR121526), revealed them as Nocardia harenae JJB5 and Amycolatopsis marina JJB11. Our results suggest that marine HMR actinomycetes are promising candidates for various biotechnological applications.

A rare case of primary cutaneous Nocardia vinacea in an immunocompetent patient: A case report and a review of the literature.

The nocardiae are a complex group of bacteria belonging to the aerobic saprophytes actinomycetes. Although nocardiosis typically occurs in immunocompromised patients, infection may occasionally develop in immunocompetent patients as well. Here we describe a rare case of primary cutaneous nocardiosis due to Nocardia vinacea in an immunocompetent 79-year-old patient. Since cutaneous nocardiosis presents variably and mimics other cutaneous infections, acid-fast and Gram stainings on clinical samples are significant to obtain a rapid and presumptive diagnosis.

Nocardia keratitis after small incision lenticule extraction (SMILE).

We report the case of a female patient in her late 20s who visited the clinic with concerns about poor vision, redness, watering and a burning sensation in her left eye 2 weeks after undergoing a small incision lenticule extraction. She had no history of systemic illness or immunosuppressed status. On slit lamp examination, she was found to have corneal stromal infiltrates in the interface at multiple locations. Given the clinical diagnosis of microbial keratitis, corneal scraping of the interface infiltrate was performed and sent for microbiological examination revealing gram-positive, thin, beaded filaments that were acid-fast positive and later identified by growth in culture media as Nocardia species. This case was managed successfully with the use of topical amikacin and systemic trimethoprim-sulfamethoxazole with complete resolution of infection.

Risk factors for Nocardia infection among allogeneic hematopoietic cell transplant recipients: A case-control study of the Infectious Diseases Working Party of the European Society for Blood and Marrow Transplantation.

OBJECTIVES: Nocardiosis is a rare but life-threatening infection after hematopoietic cell transplantation (HCT). We aimed at identifying risk factors for nocardiosis after allogeneic HCT and clarifying the effect of trimethoprim-sulfamethoxazole prophylaxis on its occurrence. METHODS: We performed a retrospective multicenter case-control study of patients diagnosed with nocardiosis after allogeneic HCT between January 2000 and December 2018. For each case, two controls were matched by center, transplant date, and age group. Multivariable analysis was conducted using conditional logistic regression to identify potential risk factors for nocardiosis. Kaplan-Meier survival curves of cases and controls were compared using log-rank tests. RESULTS: Sixty-four cases and 128 controls were included. Nocardiosis occurred at a median of 9 months after allogeneic HCT (interquartile range: 5-18). After adjustment for potential confounders in a multivariable model, Nocardia infection was associated with tacrolimus use (adjusted odds ratio [aOR] 9.9, 95 % confidence interval [95 % CI]: 1.6-62.7), lymphocyte count < 500/µL (aOR 8.9, 95 % CI: 2.3-34.7), male sex (aOR 8.1, 95 % CI: 2.1-31.5), recent use of systemic corticosteroids (aOR 7.9, 95 % CI: 2.2-28.2), and recent CMV infection (aOR 4.3, 95 % CI: 1.2-15.9). Conversely, use of trimethoprim-sulfamethoxazole prophylaxis was associated with a significantly decreased risk of nocardiosis (aOR 0.2, 95 % CI: 0.1-0.8). HCT recipients who developed nocardiosis had a significantly decreased survival, as compared with controls (12-month survival: 58 % and 90 %, respectively; p < 0.0001). CONCLUSIONS: We identified six factors independently associated with the occurrence of nocardiosis among allogeneic HCT recipients. In particular, trimethoprim-sulfamethoxazole prophylaxis was found to protect against nocardiosis.

Comparative pathogenicity of Nocardia seriolae in Nile tilapia (Oreochromis niloticus), milkfish (Chanos chanos) and Asian seabass (Lates calcarifer).

Nocardiosis, caused by Nocardia seriolae, has been a prominent disease in Southeast Asian aquaculture in the last three decades. This granulomatous disease reported in various fish species is responsible for significant economic losses. This study investigated the pathogenicity of N. seriolae in three cultured species in Taiwan: Nile tilapia (omnivore), milkfish (herbivore) and Asian seabass (carnivore). Administration of an infective dose of 1 × 106 CFU/ fish in tilapia, seabass and milkfish demonstrated mortalities of 100%, 90% and 75%, respectively. Additionally, clinical signs namely, granuloma and lesions displayed varying intensities between the groups and pathological scores. Polymerase chain reaction (PCR) amplification specific for N. seriolae was confirmed to be positive (432 bp) using NS1/NG1 primers. Post-mortem lesions revealed the absence of granulomas in tilapia and milkfish and their presence in the seabass. Interestingly, the gut in tilapia showed an influx of eosinophils suggesting its role during the acute stages of infection. However, post-challenge, surviving milkfish exhibited granulomatous formations, while surviving seabass progressed toward healing and tissue repair within sampled tissues. Overall, in conclusion, these results demonstrate the versatility in the immunological ability of individual Perciformes to contain this pathogen as a crucial factor that influences its degree of susceptibility.