Pneumocystis pneumonia in stage IIIA lung adenocarcinoma with immune-related acute kidney injury and thoracic radiotherapy:A case report

BACKGROUND Immune checkpoint inhibitors(ICIs)are therapeutic agents for advanced and metastatic non-small cell lung cancer(NSCLC)with high clinical antitumor efficacy.However,immune-related adverse events occur in 20%of these patients and often requiring treatment with immunosuppressive agents,such as corticosteroids.Consequently,this may increase the risk of patients to opportunistic infections.Pneumocystis jirovecii pneumonia(PJP),a rare but serious opportunistic infection typically observed in patients with human immunodeficiency virus,can also occur in cancer patients undergoing long-term glucocorticoid treatment.CASE SUMMARY We report a case of a 56-year-old male with squamous NSCLC treated with triplimab combined with paclitaxel,carboplatin,and radical thoracic radiation therapy.Following this regimen,he developed acute kidney injury(AKI)with elevated creatinine levels.After concurrent radical chemoradiotherapy ended,he developed a grade 3 immune-related AKI.High-dose corticosteroids were administered to treat AKI,and renal function gradually recovered.Corticosteroids were reduced to a dose of 10 mg prednisone equivalent daily eight weeks later;however,he developed severe pneumonia with spontaneous pneumothorax.Next-generation sequencing of the bronchoscopic lavage revealed PJP co-infection with herpes simplex virus 1 and cytomegalovirus.The inflammation was more severe in areas exposed to radiation.Piperacillin-tazobactam,acyclovir,sulfamethoxazole,and trimethoprim were used to control the infection.The patient recovered,and immunotherapy was terminated.CONCLUSION PJP is rare but can occur in patients with ICI adverse events and should be differentiated from tumor progression or immune-related adverse events.Thoracic radiation may increase risk,necessitating careful monitoring and prevention.

Next-generation sequencing technology for the diagnosis of Pneumocystis pneumonia in an immunocompetent female:A case report

BACKGROUND Pneumocystis pneumonia(PCP)is a serious fungal infection usually seen in patients with human immunodeficiency virus,and it is more frequently found and has a high fatality rate in immunocompromised people.Surprisingly,it rarely occurs in immunocompetent patients.However,the clinical diagnosis of this pathogen is made more difficult by the difficulty of obtaining accurate microbiological evidence with routine tests.This case reports a PCP patient with normal immune function who was diagnosed through next-generation sequencing(NGS).CASE SUMMARY A 23-year-old female who had no special disease in the past was admitted to the hospital with a persistent fever and cough.Based on the initial examination results,the patient was diagnosed with bipulmonary pneumonia,and empirical broad-spectrum antibiotic therapy was administered.However,due to the undetermined etiology,the patient's condition continued to worsen.She was transferred to the intensive care unit because of acute respiratory failure.After the diagnosis of Pneumocystis jirovecii infection through NGS in bronchoalveolar lavage fluid and treatment with trimethoprim/sulfamethoxazole and caspofungin,the patient gradually recovered and had a good prognosis.CONCLUSION This case emphasizes that,for patients with normal immune function the possibility of PCP infection,although rare,cannot be ignored.NGS plays an important role in the diagnosis of refractory interstitial pneumonia and acute respiratory failure.

Do inhaled corticosteroids increase the risk of Pneumocystis pneumonia in people with lung cancer?

Pneumocystis pneumonia(PCP) is a life-threatening infection in immunocompromised patients. It is relatively uncommon in patients with lung cancer. We report a case of PCP in a 59-year-old man with a past medical history of chronic obstructive pulmonary disease treated with formoterol and a moderate daily dose of inhaled budesonide. He had also advanced stage non-small lung cancer treated with concurrent chemo-radiation with a cisplatin-etoposide containing regimen. The diagnosis of PCP was suspected based on the context of rapidly increasing dyspnea, lymphopenia and the imaging findings. Polymerase chain reaction testing on an induced sputum specimen was positive for Pneumocystis jirovecii. The patient was treated with oral trimethoprim-sulfamethoxazole and systemic corticotherapy and had showed clinical and radiological improvement. Six months after the PCP diagnosis, he developed a malignant pleural effusion and expired on hospice care. Through this case, we remind the importance of screening for PCP in lung cancer patients under chemotherapeutic regimens and with increasing dyspnea. In addition, we alert to the fact that long-term inhaled corticosteroids may be a risk factor for PCP in patients with lung cancer. Despite intensive treatment, the mortality of PCP remains high, hence the importance of chemoprophylaxis should be considered.

Treatment of Pneumocystis jirovecii pneumonia in non-human immunodeficiency virus-infected patients using a combination of trimethoprim-sulfamethoxazole and caspofungin

BACKGROUND Pneumocystis jirovecii pneumonia(PJP)is an infectious disease common in immunocompromised hosts.However,the currently,the clinical characteristics of non-HIV patients with PJP infection have not been fully elucidated.AIM To explore efficacy of trimethoprim–sulfamethoxazole(TMP-SMX)and caspofungin for treatment of non-human immunodeficiency virus(HIV)-infected PJP patients.METHODS A retrospective study enrolled 22 patients with non-HIV-infected PJP treated with TMP-SMX and caspofungin from 2019 to 2021.Clinical manifestations,treatment and prognosis of the patients were analyzed.RESULTS Five patients presented with comorbidity of autoimmune diseases,seven with lung cancer,four with lymphoma,two with organ transplantation and four with membranous nephropathy associated with use of immunosuppressive agents.The main clinical manifestations of patients were fever,dry cough,and progressive dyspnea.All patients presented with acute onset and respiratory failure.The most common imaging manifestation was ground glass opacity around the hilar,mainly in the upper lobe.All patients were diagnosed using next-generation sequencing,and were treated with a combination of TMP-SMX and caspofungin.Among them,17 patients received short-term adjuvant glucocorticoid therapy.All patients recovered well and were discharged from hospital.CONCLUSION Non-HIV-infected PJP have rapid disease progression,high risk of respiratory failure,and high mortality.Combination of TMP-SMX and caspofungin can effectively treat severe non-HIVinfected PJP patients with respiratory failure.

Lack of Response in Severe Pneumocystis Pneumonia to Combined Caspofungin and Clindamycin Treatment: a Case Report

PNEUMOCYSTIS pneumonia (PCP) is among the most common opportunistic infections in patients with acquired immune deficiency syndrome (AIDS).Although trimethoprim-sulfamethoxazole (TMP-SMX) is the first line therapy for that condition given its efficacy,approximately one third of patients experienced dose-limiting toxicity.1 For cases of severe to moderate PCP,if TMP-SMX treatment fails or is contraindicated,primaquine combined with clindamycin or intravenous pentamidine is recommended as second line therapy.2 However,both primaquine and pentamidine are associated with severe adverse reactions and often unavailable at hospitals in China.3 As a result,other treatment options have been explored.

Pneumocystis jiroveci pneumonia after total hip arthroplasty in a dermatomyositis patient:A case report

BACKGROUND Pneumocystis jiroveci pneumonia(PJP)is a serious opportunistic infection that occurs mostly in patients with immunodeficiency and long-term immunosuppressive therapy.In non-human immunodeficiency virus-infected patients,the most important risk factor for PJP is the use of glucocorticoids in combination with other immunosuppressive treatments.The management of glucocorticoids during the perioperative period in patients with dermatomyositis requires special care.CASE SUMMARY We report a case of PJP in the perioperative period.A 61-year-old woman with a history of anti-melanoma differentiation-associated gene 5(MDA5)-positive dermatomyositis and interstitial pneumonia was administered with long-term oral methylprednisolone and cyclosporine.The patient underwent right total hip arthroplasty in the orthopaedic department for bilateral osteonecrosis of the femoral head.She was given intravenous drip hydrocortisone before anesthesia and on the first day after surgery and resumed oral methylprednisolone on the second postoperative day.On the fifth day after surgery,the patient suddenly developed dyspnea.The computed tomography scan showed diffuse grid shadows and ground glass shadows in both lungs.Polymerase chain reaction testing of bronchoalveolar lavage fluid was positive for Pneumocystis jiroveci.The patient was eventually diagnosed with PJP and was administered with oral trimethoprim-sulfamethoxazole.At the 6-mo review,there was no recurrence or progression.CONCLUSION Continued perioperative glucocorticoid use in patients with anti-MDA5-positive dermatomyositis may increase the risk of PJP.

Analysis of 8 chronic kidney disease patients complicated with Pneumocystis carinii pneumonia

Objective To study the clinical characteristics and outcome of Pneumocystis carinii pneumonia(PCP) in patients with chronic kidney diseases.Methods Clinical data of 8 cases of chronic kidney diseases complicated with PCP(excluding renal transplant patients) were examined retrospectively.Results The most common presenting symptoms at admission were fever(100%),cough without or with a little sputum(87.5%),and exertional dyspnea(75%).Beside these,they complained of chest tightness,fatigue,sweating and chills.Six patients(75%) presented with hypoxemia were diagnosed with type 1 respiratory failure during the course of illness.The most common CT feature was bilateral patchy areas of ground-glass opacities.Five patients had peripheral blood lymphocyte count less than 1 ×109/L.Four patients had CD4 cell count less than 200/mm3.Serum LDH level was elevated in 5 patients(582±222.55).Among the 8 patients,2 patients died within 20 days of PCP diagnosis.Conclusion Pneumocystis carinii pneumonia is an opportunistic and serious complication in chronic kidney disease patients treated with immunosuppressants.The disease progression is fast and patients with respiratory failure have a high mortality rate.Early diagnosis and appropriate treatment are important for better prognosis.

Clinical Analysis of 15 Cases of Non-Hodgkin Lymphoma Complicated with Pneumocystis carinii Pneumonia Treated with R-CHOP Regimen

Objective:To investigate the clinical features of R-CHOP regimen in the treatment of non-Hodgkin^lymphoma with Pneumocystis carinii pneumonia(PCP)in order to improve the understanding of PCP and the side effects of Rituxan.Methods:A retrospective analysis of 90 patients with non-Hodgkin’s lymphoma treated with R-CHOP chemotherapy in our hospital from November 2015 to November 2020,of which 15(16.7%)patients,combined with PCP clinical data,including clinical symptoms,physical signs,chest imaging examination and treatment data were used for to analysis and summarization.Results:The clinical features of R-CHOP chemotherapy combined with PCP were fever,cough,and sputum.Some patients had fewer clinical symptoms.Common imaging manifestations were double lung membrane glass shadow,patchy shadow,and flocculent shadow.It can occur in all clinical stages,and the incidence of late stage is high,and there is no clear correlation with bone marrow suppression.Pneumocystis was found in 2 cases of sputum,and the rest of the patients were clinically diagnosed.The main therapeutic drugs are sulfamethoxazole(8/15),compound sulfamethoxazole(6/15),clindamycin(1/15,sulfa drug allergy),and adrenal cortex hormones(4/15).Fourteen cases were cured and 1 case died.Conclusion:The incidence of R-CHOP in advanced non-Hodgkin^lymphoma of PCP is high.Patients with clinical use of R-CHOP chemotherapy will encounter fever,cough,chest computed tomography(CT)film glass shadow,and diffuse patch shadow.Patients should be alert to the possibility of PCP and take sulfonamides as soon as possible for medical treatment.

Metagenomic next-generation sequencing for the diagnosis of Pneumocystis jirovecii pneumonia after allogeneic hematopoietic stem cell transplantation

Objective To investigate the value of metagenomic next-generation sequencing (mNGS) in the diagnosis of Pneumocystis jirovecii pneumonia (PJP) in patients undergoing allogeneic hematopoietic stem cell transplantation (allo-HSCT).Methods The data of 98patients with suspected pulmonary infection after alloHSCT who underwent pathogen detection from bronchoalveolar lavage fluid between June 2016 and August 2023 at Nanfang Hospital were analyzed.

Metagenomic next-generation sequencing for pneumocystis jirovecii pneumonia in patients with connective tissue disease

Background:Accurate diagnosis of Pneumocystis jirovecii pneumonia(PJP)is challenging,and the delayed diagnosis of PJP is associated with high mortality in patients with connective tissue disease(CTD).Metagenomic next-generation sequencing(mNGS)technology facilitates etiological diagnosis of various infectious diseases,with promising application in diagnosing PJP.This study aimed to investigate the value of mNGS using bronchoalveolar lavage fluid(BALF)for diagnosing PJP infection.Methods:Data from 55 patients with CTD and suspected pulmonary infection was retrospectively collected and analysed.A PJP group and non-PJP group were formed.The clinical manifestations,laboratory test results,treatment methods,and outcomes were summarized.BALF mNGS results were compared with traditional pathogen tests(TPT)and serum 1,3-beta-D-glucan(BDG)testing.Results:The mean age of PJP patients was 54 years,and 59%(10/17)of the patients were female.A significant difference was found between the average daily dose of prednisone administered to the PJP group and non-PJP group(25 mg vs.16 mg,P<0.001).The PJP group had a significantly higher incidence of dyspnoea(88%[15/17]vs.16%[6/38],P<0.001)and elevated serum BDG level(167.73 vs.30.67 pg/mL,P<0.001).BALF mNGS was more sensitive than both TPT(100%[95%confidence interval{CI}:77.1%-100%]vs.11.8%[95%CI:2.1%-37.7%],P<0.001)and serum BDG(100%[95%CI:77.1%-100%]vs.85.7%[95%CI:42%-99.2%],P<0.001).BALF mNGS was more specific than serum BDG(89.5%[95%CI:74.3%-96.6%]vs.46.7%[95%CI:22.3%-72.6%],P=0.493).Co-infection with cytomegalovirus(CMV)was more common in the PJP patients than in the non-PJP patients(59%[10/17]vs.11%[4/38],respectively,P<0.001).Conclusion:BALF mNGS technology is highly effective for diagnosing PJP in patients with CTD and identifying co-infections.

Clinical characteristics and CT findings of Pneumocystis Jirovecii pneumonia in 46 cases with hematological diseases

Objective To summarize the original CT features of Pneumocystis Jirovecii pneumonia in patients with hematological diseases.Methods A retrospective analysis was carried out in 46 patients with proven pneumocystis pneumonia(PJP) in the Hospital of Hematology,Chinese Academy of Medical Sciences between January 2014 and December 2021.

A 60-Year-Male Post Corneal Transplantation with Acute Pneumonia

Pneumonia is a common complication in organ transplantation patients. Multiple respiratory pathogens such as bacteria, viruses and fungi are potentially coexisted. A 60-year-old male with left eye post corneal transplantation developed acute severe pneumonia caused by Pneumocystis jiroveci (PJP) coinfection with Nocardia spp. and Cytomegalovirus (CMV). He was hospitalized due to acute respiratory failure. Chest radiographs and chest Computed Tomography (CT) revealed extensive ground-glass opacities. PJP was diagnosed from Bronchoalveolar Lavage Fluid (BALF). The pneumonia was persistent despite of receiving intravenous cotrimoxazole. Tracheal aspirate showed faint gram-positive filamentous beaded branching organisms. Consequently Nocardia spp. was proven. Intravenous cotrimoxazole was continued and intravenous imipenem was added. After a course of dual antibiotics, pneumonia was gradually improved. A week after, he developed the worsened acute respiratory failure. The bronchoscopy was performed. The new pathogens were not detected from BALF microbiology. The BALF cytology was unremarkable. PJP was detected by Polymerase Chain Reaction (PCR) from BALF. CMV antigenemia was detected from BALF and blood. Intravenous ganciclovir was given. This report describes PJP coinfected with Nocardia spp. and CMV in post corneal transplantation patient suffering from severe pneumonia. Multiple respiratory pathogens are common among transplantation patients representing host immunosuppression and inadequate antimicorbial prophylaxis.

Diferences and similarities of high-resolution computed tomography features between pneumocystis pneumonia and cytomegalovirus pneumonia in AIDS patients

Background:Accurately diferentiating pneumocystis from cytomegalovirus pneumonia is crucial for correct therapy selection in AIDS patients.Hence,the goal of this study was to compare the computerized tomography(CT)features of pneumocystis pneumonia and cytomegalovirus pneumonia in AIDS patients and identify clinical hallmarks to accurately distinguish these two pathologies.Methods:A total of 112 AIDS patients(78 with pneumocystis pneumonia and 34 cytomegalovirus pneumonia)at Beijing Ditan Hospital from January 2017 to May 2019 were included in this study.Two experienced chest radiologists retrospectively reviewed CT images for 17 features including ground-glass opacity,consolidation,nodules,and halo sign.Binary logistic regression analyses were conducted to identify the signifcant parameters that distinguished pneumocystis pneumonia from cytomegalovirus pneumonia.Correlations were analyzed by Pearson or Spearman correlation analyses.Result were considered signifcant if P<0.05.Results:The presence of consolidation,halo signs,and nodules(all P<0.05)were signifcantly more frequent in patients with cytomegalovirus pneumonia than in those with pneumocystis pneumonia.Small nodules(32.5%in cytomegalovirus pneumonia,6.41%in pneumocystis pneumonia,P<0.001)without perilymphatic distribution were particularly common in patients with cytomegalovirus pneumonia.Large nodules were not found in any of patients with cytomegalovirus pneumonia.The presence of ground-glass opacity,reticulation,and bronchial wall thickening(all P>0.05)were common in both groups.Conclusions:Analysis of consolidation,nodules,and halo signs may contribute to the diferential diagnosis of pneumocystis pneumonia or cytomegalovirus pneumonia.However,some CT features considered typical in one or other diseases appear with similar frequency in both cohorts of AIDS patients.CT features are potentially useful for the diferential diagnosis of pneumocystis pneumonia and cytomegalovirus pneumonia in AIDS patients.

Alteration of surfactant proteins A and D in bronchoalveolar lavage fluid of pneumocystis carinii pneumonia

Objective To understand the interaction between surfactant proteins and pneumocystis carinii pneumonia (PCP),and the impact of corticosteriods on surfactant proteins.Methods We established rat models of PCP and bacterial pneumonia induced by subcutaneous injection of 25mg cortisone acetate.At 8- 12 wk,the bronchoalveolar lavage fluid(BALF)of rats was collected.Total nucleated cells of BALF were counted and differentiated,and the concentrations of surfactant protein A(SP-A)and surfactant protein D(SP-D)were measured by immunoblotting assay.The rats were divided into three immunosuppressive groups and a normal control group.Group I,normal control(n = 6),consisted of healthy SD rats;group Ⅱ,negative control(n = 6),consisted of rats with cortisone acetate injection for over 8 wk without lung infection;group Ⅲ,bacterial pneumonia(n = 11),rats were injected with cortisone acetate over 8 wk that resulted in bacterial pneumonia without other pathogens isolated;and group Ⅳ,PCP(n = 14),rats with injected cortisone acetate for 8 - 12 wk and developed PCP without other pathogens isolated.Results Our results indicated that the total cell count in BALF in the negative control group was lower than that in the normal control group(P ＜ 0.001).During PCP infection,the total cell count and the percentage of polymorphonuclearcytes(PMNs)in BALF were significantly increased(P ＜ 0.01),but were lower than those in the bacterial pneumonia group.The concentration of SP-A of BALF in PCP(45.1 ± 22.1 μg/ml)was significantly increased in comparison with that in the negative control(16.2 ± 9.9 μg/ml,P ＜ 0.05)and bacterial pneumonia groups(6.2 ± 5.6 μg/ml,P ＜ 0.001).We also found that the relative content of SP-D was significantly higher in PCP(24249 ±4780 grey values)than that in the negative control (13 384 ± 2887 grey values,P ＜ 0.001)and that in bacterial pneumonia(11 989 ± 2750 grey values,P＜0.001).SP-A and SP-D were also higher in the moderate to heavy group of PCP than those seen in the mild group(P ＜ 0.01,P ＜ 0.001).SP-A and SP-D were higher in the negative control group than those in the normal control group,but there was no significant difference between the 2 groups.Conclusion These results suggest that the concentrations of SP-A and SP-D in BALF are increased by pneumocystis carinii specific stimulation,but the alteration is not related to the corticosteriod usage.

Relationship between Radiological Stages and Prognoses of Pneumocystis Pneumonia in Non-AIDS Immunocompromised Patients

Background： Although radiological features ofpneumocystis pneumonia （PCP） in non-Acquired Immune Deficiency Syndrome （AIDS） immunocompromised patients have been reported by other authors, there were no studies on the radiological stages of PCP previously. This study aimed to elucidate the radiological stages and prognoses of PCP in non-AIDS immunocompromised patients. Methods： Retrospective analysis ofradiological manifestations and prognoses of 105 non-AIDS PCP immunocompromised patients from August 2009 to April 2016 was conducted. Chest radiograph was divided into three stages： early stage （normal or nearly normal chest radiograph）, mid stage （bilateral pulmonary infiltrates）, and late stage （bilateral pulmonary consolidations）; chest high-resolution computed tomography （HRCT） was also divided into three stages： early stage （bilateral diffuse ground-glass opacity [GGO]）, mid stage （bilateral diffuse GGO and patchy consolidations）, and late stage （bilateral diffuse consolidations）. Results： The case fatality rate （CFR） of all patients was 34.3% （36/105）, all of them took routine chest X-ray （CXR）, and 84 underwent chest CT examinations. According to the CXR most near the beginning ofanti-PCP therapy, 18 cases were at early stage and CFR was 0 （0/18, P 〈 0.01）, 50 cases were at mid stage and CFR was 28.0% （14/50, P〉 0.05）, and 37 cases were at late stage and CFR was 59.5% （22/37, P 〈 0.01）. According to the chest HRCT most near the beginning ofanti-PCP therapy, 40 cases were at early stage and CFR was 20.0% （8/40, P 〉 0.05）, 34 cases were at mid stage and CFR was 47.1% （l 6/34, P 〉 0.05）, and 10 cases were at late stage and CFR was 80.0% （8/10, P 〈 0.05）; barotrauma, including pneumothorax, pneumomediastinum, and pneumohypoderma, was found in 18 cases and the CFR was 77.8% （14/18, P 〈 0.01）. Conclusions： Based on the radiological manifestations, the course of PCP in non-A1DS immunocompromised patients can be divided into three stages： early stage, mid stage, and late stage. The prognoses of patients treated at early stage are good, and those at late stage are poor. Furthermore, the CFR of patients with barotrauma is high.

Caspofungin in salvage treatment of severe pneumocystis pneumonia： case report and literature review

Pneumocystis pneumonia （PCP） is one of the most critical and life-threatening infections in immunocompromised patients with AIDS （especially CD4^＋ T cell less than 0.2×10^9/L）, hematological malignancies, organ transplantation or connective tissue diseases. It is caused by a fungus called Pneumocystis jiroveci （P. jiroveci, formerly called P carinii）.

A clinical comparative study of polymerase chain reaction assay for diagnosis of pneumocystis pneumonia in non-AIDS patients

Background Pneumocystis jirovecii pneumonia （PCP） is one of the most common and fatal infections in non-AIDS immunocompromised patients, which is difficult to diagnose by traditional morphologic methods. This study evaluated polymerase chain reaction （PCR） assays of Pneumocystis jirovecii mitochondrial large subunits ribosomal RNA in sputum and bronchioalveolar lavage fluid （BALF） for diagnosing PCP. Methods Sputum and BALF specimens from two groups were collected： one group （PCP group） included 20 patients definitely diagnosed of PCP by Gomori methenamine silver （GMS） stains of BALF; the other group （non-PCP group） included 40 patients. Each specimen was examined by GMS stains and PCR assays. Results GMS stains of BALF in PCP group were 100% positive （20/20）, GMS stains of sputum in PCP group were 35% positive （7/20）; GMS stains of BALF in non-PCP group were 100% negative （40/40）, GMS stains of sputum in non-PCP group were 100% negative （40/40）. PCR assays of BALF in PCP group were 100% positive （20/20）, PCR assays of sputum in PCP group were 100% positive （20/20）; PCR assays of BALF in non-PCP group were 100% negative （40/40）, PCR assays of sputum in non-PCP group were 100% negative （40/40）. Sensitivity and specificity of PCR assays of sputum and BALF were both 100%; positive and negative predictive values were also both 100%. Conclusion The diagnostic value of PCR assays of Pneumocystisjirovecii mitochondrial large subunits ribosomal RNA on sputum and BALF for pneumocystis pneumonia are both high and equivalent.

Use of real-time polymerase chain reaction for the diagnosis of Pneumocystis pneumonia in immunocompromised patients： a meta-analysis

Background The diagnosis of Pneumocystis pneumonia （PCP） in immunocompromised patients is still challenging today due to the absence of an in vitro culture system and the low diagnostic accuracy of microscopic examinations. Herein, we performed a meta-analysis to evaluate the accuracy of real-time polymerase chain reaction （PCR） in the diagnosis of PCP. Methods We searched Web of Knowledge and Medline from 1990 to May 2010 for studies reporting diagnostic accuracy data regarding the use of real-time PCR in the diagnosis of PCP in immunocompromised patients. Results Ten individual studies were included. Overall, the sensitivity of real-time PCR was 97% （95% CI： 93%-99%）; the specificity was 94% （95% CI： 90%-96%）. The area under the HSROC curve （95% CO for real-time PCR was 0.99 （0.97-0.99）. In a subgroup analysis regarding studies involving HIV patients among the study population, the sensitivity and specificity were 97% （95% CI： 93%-99%） and 93% （95% CI： 89%-96%）, respectively. Regarding studies using Bronchoalveolar lavage （BAL） samples only： sensitivity =98% （95% CI： 94%-99%）; specificity =93% （95% CI： 89%- 96%）, respectively. Regarding studies using microscopy as a reference standard： sensitivity =97% （95% CI： 92%-99%）; specificity =93% （95% CI： 88%-96%）. However, high between-study statistical heterogeneity was observed in all analyses. Conclusions Real-time PCR has a good diagnostic accuracy and may provide a useful adjunctive tool for the diagnosis of PCP in immunocompromised patients. Further studies are needed in order to identify any differences in the diagnostic performance of real-time PCR in HIV and non-HIV immunocompromised patients.

Clinical parameters and outcomes of Pneumocystis jiroveci pneumonia in non-HIV/AIDS patients

Pneumocystis jiroveci pneumonia （PCP） is one of the most serious and potentially fatal infectionsencountered in immonosuppressed patients. It remains the most common cause of pulmonary morbidity and mortality in patients infected with human immunodeficiency virus （HIV）.

Metagenomic next-generation sequencing for the diagnosis of Pneumocystis jirovecii pneumonia in solid organ transplant recipients

To the Editor:Pneumocystis jirovecii(P.jirovecii)pneumonia(PJP)is an opportunistic infection that usually occurs in immunosuppressed patients.Solid organ transplant(SOT)recipients have a high incidence of PJP due to the use of immunosuppressive therapy.In recent years,metagenomic next-generation sequencing(mNGS)has been increasingly used in the diagnosis of infectious diseases.Herein,we report ten cases of PJP diagnosed by mNGS and compare the diagnostic value of mNGS with that of conventional laboratory methods.