Pulmonary nocardiosis with bloodstream infection diagnosed by metagenomic next-generation sequencing in a kidney transplant recipient:A case report

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.

Pulmonary nocardiosis due to Nocardia otitidiscaviarum in an immunocompetent host-A rare case report

Nocardiosis is a localized or disseminated infection caused by soil-borne aerobic actinomycetes. Pulmonary nocardiosis is a rare infection mostly occurring in immunocompromised patients.We reported a case of 36 year old immunocompetent non-smoker female patient with no premorbid illness who presented with fever,cough with scanty sputum,hemoptysis,left sided chest pain and exertional dyspnea for two weeks.There was no past history of tuberculosis,diabetes mellitus or steroid therapy.Chest X-ray showed homogenous peripherally based opacity in the left upper zone.Bronchoscopy was done and brushing sent for culture,which showed colonies with features of Nocardia species after 48 hours.Further phenotypic characterization revealed it to be Nocardia otitidiscaviarum.Patient was treated with cotrimaxazole for six months after which complete recovery was evidenced symptomatically and radiologically.We report this case to emphasize the fact that among the Nocardia species,Nocardia otitidiscaviarum as causative agent of pulmonary disease is rarely reported even in immunocompromised individuals.

Pulmonary alveolar proteinosis complicated with nocardiosis: A case report and review of the literature

BACKGROUND Pulmonary alveolar proteinosis(PAP)is a pulmonary syndrome wherein large volumes of phospholipid and protein-rich surfactants accumulate within the alveoli.PAP forms include primary(auto-immune PAP),secondary,and congenital.Nocardiosis is a form of suppurative disease induced upon infection with bacteria of the Nocardia genus.Clinically,cases of PAP complicated with Nocardia infections are rare,regardless of form.Unfortunately,as such,they are easily overlooked or misdiagnosed.We describe,here,the case of a patient suffering from simultaneous primary PAP and nocardiosis.CASE SUMMARY A 45-year-old Chinese man,without history of relevant disease,was admitted to our hospital on August 8,2018 to address complaints of activity-related respiratory exertion and cough lasting over 6 mo.Lung computed tomography(CT)revealed diffuse bilateral lung infiltration with local consolidation in the middle right lung lobe.Subsequent transbronchial lung biopsy and CT-guided lung biopsy led to a diagnosis of primary PAP(granulocyte-macrophage colonystimulating factor antibody-positive)complicated with nocardiosis(periodic acid-Schiff-positive).After a 6 mo course of anti-infective treatment(sulfamethoxazole),the lesion was completely absorbed,such that only fibrous foci remained,and the patient exhibited significant symptom improvement.Followup also showed improvement in pulmonary function and the CT imaging findings of PAP.No whole-lung lavage has been conducted to date.This case highlights that active anti-nocardia treatment may effectively improve the symptoms and alleviate PAP in patients with PAP and nocardia,possibly reducing the need for whole-lung lavage.CONCLUSION When evaluating patients presenting with PAP and pulmonary infections, thepotential for nocardiosis should be considered.

Disseminated nocardiosis due to Nocardia otitidiscaviarum:A case report and literature review

Rationale: Disseminated nocardiosis due to Nocardia otitidiscaviarum is rarely reported in immunocompetent hosts.Patient concerns: A 59 year old male patient complained of painful soft tissue swellings and fever for two days.Diagnosis: Disseminated nocardiosis due to Nocardia otitidiscaviarum. Interventions: Initial antimicrobial therapy with imipenem and trimethoprim/sulfamethoxazole was switched to 6 weeks of trimethoprim/sulfamethoxazole, linezolid and tigecycline after sensitivity test results were available. Thereafter, the patient was switched to maintenance trimethoprim/sulfamethoxazole and moxifloxacin. Prednisolone was gradually tapered.Outcomes: Soft tissue swelling and pain disappeared and the patient was discharged uneventfully.Lessons: Disseminated nocardiosis due to Nocardia otitidiscaviarum should be suspected in immunocompetent hosts with risk factors such as medication with prednisolone. Early identification of the causative species and susceptibility results is crucial given the diverse resistance patterns amongst various Nocardia species.

Successful treatment of disseminated nocardiosis diagnosed by metagenomic next-generation sequencing:A case report and review of literature

BACKGROUND Nocardia paucivorans is an infrequently found bacterium with the potential to cause severe infection,with a predilection for the central nervous system,both in immunocompromised and immunocompetent individuals.Rapid etiological diagnosis of nocardiosis can facilitate timely and rational antimicrobial treatment.Metagenomic next-generation sequencing(m NGS)can improve the rate and reduce the turnaround time for the detection of Nocardia.CASE SUMMARY A 49-year-old man was admitted to hospital with cough and hemoptysis.Imaging revealed pulmonary consolidation as well as multiple brain lesions.Nocardia asiatica and Nocardia beijingensis were rapidly detected by m NGS of bronchoalveolar lavage fluid(BALF)while bacterial culture of BALF and pathological biopsy of lung tissue were negative.In early stages,he was treated with trimethoprim-sulfamethoxazole(TMP-SMZ)and linezolid by individual dose adjustment based on serum concentrations and the adverse effects of thrombocytopenia and leukopenia.The treatment was then replaced by TMP-SMZ and ceftriaxone or minocycline.He was treated with 8 mo of parenteral and/or oral antibiotics,and obvious clinical improvement was achieved with resolution of pulmonary and brain lesions on repeat imaging.CONCLUSION m NGS provided fast and precise pathogen detection of Nocardia.In disseminated nocardiosis,linezolid is an important alternative that can give a better outcome with the monitoring of linezolid serum concentrations and platelet count.

Nocardiosis with diffuse involvement of the pleura:A case report

BACKGROUND Nocardiosis is an uncommon infection that usually occurs in immunocompromised patients,and the pulmonary system is the most common site.We report an uncommon case of nocardiosis with diffuse involvement of the pleura,which presented as multiple localized nodular or hillock lesions on computed tomography(CT)with local chest wall infiltration.CASE SUMMARY A 54-year-old woman was referred to our hospital due to cough and fever for 20 d.She had a history of nephrotic syndrome for 7 mo and was given prednisone(60 mg/d)6 mo previously.The hormone was then gradually reduced to the current dose of 25 mg/d.Chest CT showed many nodular or hillock lesions in the right pleura,mediastinum,and interlobar fissure areas.On the lower layer,one lesion infiltrated the chest wall.She was treated with piperacillin sodium and sulbactam sodium,but the therapeutic effect was not good.In this regard,ultrasound-guided local infiltration anesthesia was further conducted for perihepatic hydrops drainage to improve diagnostic accuracy.Puncture fluid culture isolated Nocardia species,confirming the diagnosis of nocardiosis.Subtype Nocardia farcinica was identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry.Antibiotic treatment was switched to trimethoprim/sulfamethoxazole and imipenem.After 8 d of treatment,the patient was discharged from the hospital with improved condition,and she has been recurrence-free for 2 years.CONCLUSION This report illustrates that nocardiosis should be suspected when clinicians encounter patients who are immunocompromised and have diffuse involvement of the pleura.

Primary lymphocutaneous nocardiosis associated with gardening: A case series

Most cases of nocardiosis are seen in immunocompromised patients. Primary lymphocutaneous is a relatively uncommon presentation of this disease that may also occurs in normal hosts. Diagnosing this infection requires a high index of suspicion since cultures can take several days to exhibit growth. The microbiology laboratory must therefore be notified about cases in which this pathogen is suspected. We report four cases of primary lymphocutaneous norcardiosis. Of particular interest is the association of three of these cases with gardening.

A Novel Case of Pulmonary Nocardiosis with Secondary Hemophagocytic Lymphohistiocytosis

Pulmonary nocardiosis is an opportunistic infection,especially in immunocompromised patients.Hemophagocytic lymphohistiocytosis （HLH） is a rare but potentially fatal disease.We report a case of pulmonary nocardiosis with secondary HLH.

Nocardia infections among immunomodulated inflammatory bowel disease patients:A review

Human nocardiosis,caused by Nocardia spp.,an ubiquitous soil-borne bacteria,is a rare granulomatous disease close related to immune dysfunctions.Clinically can occur as an acute life-threatening disease,with lung,brain and skin being commonly affected.The infection was classically diagnosed in HIV infected persons,organ transplanted recipients and long term corticosteroid treated patients.Currently the widespread use of immunomodulators and immunossupressors in the treatment of inflammatory diseases changed this scenario.Our purpose is to review all published cases of nocardiosis in immunomodulated patients due to inflammatory diseases and describe clinical and laboratory findings.We reviewed the literature concerning human cases of nocardiosis published between 1980 and 2014 in peer reviewed journals.Eleven cases of nocardiosis associated with anti-tumor necrosis factor(TNF) prescription(9 related with infliximab and 2 with adalimumab) were identified; 7 patients had inflammatory bowel disease(IBD),4 had rheumatological conditions; nocardia infection presented as cutaneous involvement in 3 patients,lung disease in 4 patients,hepatic in one and disseminated disease in 3 patients.From the 10 cases described in IBD patients 7 were associated with anti-TNF and 3 with steroids and azathioprine.In conclusion,nocardiosis requires high levels of clinical suspicion and experience of laboratory staff,in order to establish a timely diagnosis and by doing so avoid worst outcomes.Treatment for long periods tailored by the susceptibility of the isolated species whenever possible is essential.The safety of restarting immunomodulators or anti-TNF after the disease or the value of prophylaxis with cotrimoxazole is still debated.

Diversity and frequency of Nocardia spp.in the soil of Isfahan province,Iran

Objective:To isolate and identify Nocardiaspp. from soil in different regions of Isfahan province in the center of Iran.Methods:This study was conducted in 32 districts(16 cities and 16 villages)in Isfahan province during two years. A total of 800 soil samples from these regions were studied by using kanamycin. The isolated Nocardiaspecies were examined by gram and acid-fast staining and were identified biochemically and morphologically. The frequency and distribution of Nocardia spp. were determined in relation to different factors such as soil pH and temperate climate.Results:From 153(19.1%)Nocardiaisolates identified,Nocardia asteroids(N. asteroids)complex(45.5%) andNocardia brasiliensis(N. brasiliensis)(24.7%) were the most frequently isolated species, followed by Nocardia otitidiscaviarum (2.2%),Nocardiopsis dassonvillei,Actinom adura actinomadura(each 1.7%) and Nocardia transvalensis(1.1%) and also unknown spp.(23.0%). In this study, most species(54.4%) of Nocardia, especially N. asteroides complex were isolated fromsoils with pH: 7.01-8, whereas in pH: 8.01-9 more N. brasiliensis was isolated. The most Nocardia spp. was detected from regions with semi-nomadic and temperate climate(41.1%).Conclusions:N. asteroids complex is more prevalent in Isfahan province and soil can be a potential source of nocardiosis infections. It is to be considering that climate and soil pH are involved in the frequency and diversity of aerobic Actinomy cetes.

Nocardial brain abscess in an immunocompetent patient and review of literature

Background:Nocardial brain abscesses are associated with significant morbidity and mortality rates.The optimal management remains unclear.Case presentation:We report a case of 49-year-old woman presented with dizziness,progressive headache for 3 days,accompanied with left arm twitched for twice.The patient underwent a right parietal craniotomy for resection of the lesion.Gross total resection of the lesion was achieved.There were no new neurological deficits post-operatively,and no lesions was demonstrated on Gd-enhanced MRI images at six months follow-up.Conclusions:After review of the literature and experience learned from our case,we suggest that craniotomy and surgical resection of the lesions,instead of aspiration,is a safe,efficacious treatment for the patient with nocardial brain abscesses.Long-term chemotherapy and follow-up is mandatory in all cases.