BACKGROUND Infections by non-tuberculous mycobacteria(NTM)have become more common in recent years.Mycobacterium canariasense(M.canariasense)was first reported as an opportunistic pathogen in 2004,but there have been v...BACKGROUND Infections by non-tuberculous mycobacteria(NTM)have become more common in recent years.Mycobacterium canariasense(M.canariasense)was first reported as an opportunistic pathogen in 2004,but there have been very few case reports since then.Nocardia is a genus of aerobic and Gram-positive bacilli,and these species are also opportunistic pathogens and in the Mycobacteriales order.Conventional methods for diagnosis of NTM are inefficient.Metagenomic next-generation sequencing(mNGS)can rapidly detect many pathogenic microorganisms,even rare species.Most NTM and Nocardia infections occur in immunocompromised patients with atypical clinical symptoms.There are no previous reports of infection by M.canariasense and Nocardia farcinica(N.farcinica),especially in immunocompetent patients.This case report describes an immunocompetent 52-year-old woman who had overlapping infections of M.canariasense,N.farcinica,and Candida parapsilosis(C.parapsilosis)based on mNGS.CASE SUMMARY A 52-year-old woman presented with a productive cough and chest pain for 2 wk,and recurrent episodes of moderate-grade fever for 1 wk.She received antibiotics for 1 wk at a local hospital,and experienced defervescence,but the productive cough and chest pain persisted.We collected samples of a lung lesion and alveolar lavage fluid for mNGS.The lung tissue was positive for M.canariasense,N.farcinica,and C.parapsilosis,and the alveolar lavage fluid was positive for M.canariasense.The diagnosis was pneumonia,and application of appropriate antibiotic therapy cured the patient.CONCLUSION Etiological diagnosis is critical for patients with infectious diseases.mNGS can identify rare and novel pathogens,and does not require a priori knowledge.展开更多
Bacterial keratitis is an infection of the cornea.This kind of infection can progress quickly and if left untreated,it can eventually cause complete blindness.While Staphylococcus aureus and Pseudomonas aeruginosa are...Bacterial keratitis is an infection of the cornea.This kind of infection can progress quickly and if left untreated,it can eventually cause complete blindness.While Staphylococcus aureus and Pseudomonas aeruginosa are most commonly responsible for this type of infection in the United States,Nocardia spp.is rarely encountered.Here we describe an interesting case of Nocardia farcinica keratitis in a 31-year-old male patient having an extended wear of contact lenses.The patient presented at the emergency department with irritation,foreign body sensation,redness,and pain of his left eye.Nocardia farcinica was isolated from a corneal scraping specimen,and determined by sequencing a region of 16S rRNA gene.The patient had antimicrobial therapy with good improvement.We highlight the important role of Nocardia farcinica in causing keratitis,and its accurate and timely diagnosis is needed to avoid poor visual outcomes.展开更多
BACKGROUND Pulmonary nocardiosis is difficult to diagnose by culture and other conventional testing,and is often associated with lethal disseminated infections.This difficulty poses a great challenge to the timeliness...BACKGROUND Pulmonary nocardiosis is difficult to diagnose by culture and other conventional testing,and is often associated with lethal disseminated infections.This difficulty poses a great challenge to the timeliness and accuracy of clinical detection,especially in susceptible immunosuppressed individuals.Metagenomic nextgeneration sequencing(mNGS)has transformed the conventional diagnosis pattern by providing a rapid and precise method to assess all microorganisms in a sample.CASE SUMMARY A 45-year-old male was hospitalized for cough,chest tightness and fatigue for 3 consecutive days.He had received a kidney transplant 42 d prior to admission.No pathogens were detected at admission.Chest computed tomography showed nodules,streak shadows and fiber lesions in both lung lobes as well as right pleural effusion.Pulmonary tuberculosis with pleural effusion was highly suspected based on the symptoms,imaging and residence in a high tuberculosisburden area.However,anti-tuberculosis treatment was ineffective,showing no improvement in computed tomography imaging.Pleural effusion and blood samples were subsequently sent for mNGS.The results indicated Nocardia farcinica as the major pathogen.After switching to sulphamethoxazole combined with minocycline for antinocardiosis treatment,the patient gradually improved and was finally discharged.CONCLUSION A case of pulmonary nocardiosis with an accompanying bloodstream infection was diagnosed and promptly treated before the dissemination of the infection.This report emphasizes the value of mNGS in the diagnosis of nocardiosis.mNGS may be an effective method for facilitating early diagnosis and prompt treatment in infectious diseases,which overcomes the shortcomings of conventional testing.展开更多
目的探讨肺鼻疽奴卡菌病合并多发脑脓肿的病原学特点,为临床诊疗该类疾病提供依据。方法分析患者的临床资料、影像学检查、诊疗经过和实验室对病原菌的分离鉴定、药敏试验和16S r RNA序列测定并复习相关文献。结果该患者有长期服用糖皮...目的探讨肺鼻疽奴卡菌病合并多发脑脓肿的病原学特点,为临床诊疗该类疾病提供依据。方法分析患者的临床资料、影像学检查、诊疗经过和实验室对病原菌的分离鉴定、药敏试验和16S r RNA序列测定并复习相关文献。结果该患者有长期服用糖皮质激素史,临床表现为发热、咳嗽等,实验室检测白细胞、中性粒细胞、C-反应蛋白升高;痰培养2 d后有细菌生长,菌落白色粗糙、有皱褶,革兰染色镜检为串珠状或分枝状革兰阳性杆菌,1%硫酸弱抗酸染色及抗酸染色均阴性;分离菌经细菌自动化鉴定仪鉴定未出结果,质谱和16S r RNA测序鉴定为鼻疽奴卡菌。药敏结果显示阿米卡星、环丙沙星、亚胺培南、左氧氟沙星、利奈唑胺和米诺环素敏感,复方新诺明、头孢曲松、氨苄西林和红霉素耐药。肺部影像学显示,双肺多发斑片状阴影、结节,后发展为空洞,脑CT示多发脑脓肿。应用复方磺胺甲噁唑和头孢曲松联合治疗后肺部空洞吸收好转,经外科手术引流及脓肿切除后患者病情稳定,回当地治疗。结论分子学方法鉴定鼻疽奴卡菌快速、准确,早期病原诊断是治疗奴卡菌病的关键,治疗应以磺胺类为主的联合治疗、早期、足量、足疗程。展开更多
基金Supported by The Guangxi TCM Suitable Technology Development and Promotion Project,No.GZSY20-20.
文摘BACKGROUND Infections by non-tuberculous mycobacteria(NTM)have become more common in recent years.Mycobacterium canariasense(M.canariasense)was first reported as an opportunistic pathogen in 2004,but there have been very few case reports since then.Nocardia is a genus of aerobic and Gram-positive bacilli,and these species are also opportunistic pathogens and in the Mycobacteriales order.Conventional methods for diagnosis of NTM are inefficient.Metagenomic next-generation sequencing(mNGS)can rapidly detect many pathogenic microorganisms,even rare species.Most NTM and Nocardia infections occur in immunocompromised patients with atypical clinical symptoms.There are no previous reports of infection by M.canariasense and Nocardia farcinica(N.farcinica),especially in immunocompetent patients.This case report describes an immunocompetent 52-year-old woman who had overlapping infections of M.canariasense,N.farcinica,and Candida parapsilosis(C.parapsilosis)based on mNGS.CASE SUMMARY A 52-year-old woman presented with a productive cough and chest pain for 2 wk,and recurrent episodes of moderate-grade fever for 1 wk.She received antibiotics for 1 wk at a local hospital,and experienced defervescence,but the productive cough and chest pain persisted.We collected samples of a lung lesion and alveolar lavage fluid for mNGS.The lung tissue was positive for M.canariasense,N.farcinica,and C.parapsilosis,and the alveolar lavage fluid was positive for M.canariasense.The diagnosis was pneumonia,and application of appropriate antibiotic therapy cured the patient.CONCLUSION Etiological diagnosis is critical for patients with infectious diseases.mNGS can identify rare and novel pathogens,and does not require a priori knowledge.
文摘Bacterial keratitis is an infection of the cornea.This kind of infection can progress quickly and if left untreated,it can eventually cause complete blindness.While Staphylococcus aureus and Pseudomonas aeruginosa are most commonly responsible for this type of infection in the United States,Nocardia spp.is rarely encountered.Here we describe an interesting case of Nocardia farcinica keratitis in a 31-year-old male patient having an extended wear of contact lenses.The patient presented at the emergency department with irritation,foreign body sensation,redness,and pain of his left eye.Nocardia farcinica was isolated from a corneal scraping specimen,and determined by sequencing a region of 16S rRNA gene.The patient had antimicrobial therapy with good improvement.We highlight the important role of Nocardia farcinica in causing keratitis,and its accurate and timely diagnosis is needed to avoid poor visual outcomes.
文摘BACKGROUND Pulmonary nocardiosis is difficult to diagnose by culture and other conventional testing,and is often associated with lethal disseminated infections.This difficulty poses a great challenge to the timeliness and accuracy of clinical detection,especially in susceptible immunosuppressed individuals.Metagenomic nextgeneration sequencing(mNGS)has transformed the conventional diagnosis pattern by providing a rapid and precise method to assess all microorganisms in a sample.CASE SUMMARY A 45-year-old male was hospitalized for cough,chest tightness and fatigue for 3 consecutive days.He had received a kidney transplant 42 d prior to admission.No pathogens were detected at admission.Chest computed tomography showed nodules,streak shadows and fiber lesions in both lung lobes as well as right pleural effusion.Pulmonary tuberculosis with pleural effusion was highly suspected based on the symptoms,imaging and residence in a high tuberculosisburden area.However,anti-tuberculosis treatment was ineffective,showing no improvement in computed tomography imaging.Pleural effusion and blood samples were subsequently sent for mNGS.The results indicated Nocardia farcinica as the major pathogen.After switching to sulphamethoxazole combined with minocycline for antinocardiosis treatment,the patient gradually improved and was finally discharged.CONCLUSION A case of pulmonary nocardiosis with an accompanying bloodstream infection was diagnosed and promptly treated before the dissemination of the infection.This report emphasizes the value of mNGS in the diagnosis of nocardiosis.mNGS may be an effective method for facilitating early diagnosis and prompt treatment in infectious diseases,which overcomes the shortcomings of conventional testing.
文摘目的探讨肺鼻疽奴卡菌病合并多发脑脓肿的病原学特点,为临床诊疗该类疾病提供依据。方法分析患者的临床资料、影像学检查、诊疗经过和实验室对病原菌的分离鉴定、药敏试验和16S r RNA序列测定并复习相关文献。结果该患者有长期服用糖皮质激素史,临床表现为发热、咳嗽等,实验室检测白细胞、中性粒细胞、C-反应蛋白升高;痰培养2 d后有细菌生长,菌落白色粗糙、有皱褶,革兰染色镜检为串珠状或分枝状革兰阳性杆菌,1%硫酸弱抗酸染色及抗酸染色均阴性;分离菌经细菌自动化鉴定仪鉴定未出结果,质谱和16S r RNA测序鉴定为鼻疽奴卡菌。药敏结果显示阿米卡星、环丙沙星、亚胺培南、左氧氟沙星、利奈唑胺和米诺环素敏感,复方新诺明、头孢曲松、氨苄西林和红霉素耐药。肺部影像学显示,双肺多发斑片状阴影、结节,后发展为空洞,脑CT示多发脑脓肿。应用复方磺胺甲噁唑和头孢曲松联合治疗后肺部空洞吸收好转,经外科手术引流及脓肿切除后患者病情稳定,回当地治疗。结论分子学方法鉴定鼻疽奴卡菌快速、准确,早期病原诊断是治疗奴卡菌病的关键,治疗应以磺胺类为主的联合治疗、早期、足量、足疗程。
