Pneumocystis carinii pneumonia

Throughout the epidemic, Pneumocystis carinii pneumonia (PCP) has been the most common AIDS-defining opportunistic infection in the United States. With the widespread use of highly active antiretroviral therapy (HAART) and prophylaxis in patients known to be at risk, the incidence of PCP in patients with AIDS has declined dramatically. However, it is still seen regularly in patients with previously undiagnosed human immunodeficiency virus (HIV) infection, those who do not comply with prophylactic medications, and in occasional cases of failure of prophylaxis. Despite many years of study, our understanding of the biology, ecology, and pathogenesis of PCP is inadequate. Clinically, PCP in AIDS tends to be a less acute and milder illness than PCP in other types of immunocompromised hosts. Although the radiograph typically shows bilateral diffuse granular opacities, many other patterns are seen. Trimethoprim-sulfamethoxazole is the preferred drug for treating and preventing PCP, but toxicity limits its use. The choice of treatment is influenced by the severity of illness and relative toxicities of antipneumocystis agents. Adjunctive corticosteroid therapy is recommended for patients with moderate or severe disease. The success of HAART has prompted investigators to question whether prophylaxis against PCP and other opportunistic infections is necessary in patients who respond with a rise in CD4 lymphocyte counts and suppression of HIV replication.     

Purified capsular polysaccharide-induced immunity to Staphylococcus aureus infection

In this study, we determined that immunization with capsular polysaccharide from Staphylococcus aureus could protect mice against nonlethal infections induced by encapsulated staphylococci. We immunized mice with either formalin-killed bacteria or purified capsular polysaccharide (PCP) and challenged them with one of three related S. aureus strains that varied in capsule size. Quantitative cultures of blood and kidney from the animals were performed to evaluate protection. Immunization with whole bacteria protected mice against infection with the homologous strain. Mice immunized with PCP were protected when challenged intravenously with either a highly encapsulated S. aureus strain or a microencapsulated mutant but not with an unencapsulated mutant. Protection correlated with capsular antibody levels in the immunized animals. Immunity to staphylococcal infection could be passively transferred to naive animals by using immune serum. These experiments suggest that the S. aureus capsular polysaccharide merits further study as a potential vaccine candidate for preventing staphylococcal infection.     

浙贝母素乙治疗大鼠卡氏肺孢子虫肺炎的实验研究

目的探讨浙贝母素乙注射液对大鼠卡氏肺孢子虫肺炎（PCP）的治疗作用,寻找杀灭或抑制卡氏肺孢子虫繁殖的药物,以提高包括艾滋病病人在内的免疫功能低下患者的生存质量。方法选择健康SD大鼠用地塞米松皮下注射,连续8周,每周2次,建立大鼠PCP模型;腹腔内注射不同剂量的浙贝母素乙注射液,连续5d,同时设有感染对照组和正常对照组。停药2周后杀鼠取肺,观察浙贝母素乙对大鼠肺内卡氏肺孢子虫发育的影响,肺组织印片检查包囊,肺组织病理切片染色观察组织变化。结果注射浙贝母素乙液注射组大鼠的肺组织印片包囊数量较治疗前明显减少,肺组织炎症反应明显好转。结论中药浙贝母素乙注射液对肺孢子虫在肺内发育有明显的抑制作用,有望用于PCP的治疗。     

Risk factors of Pneumocystis jeroveci pneumonia in patients with systemic lupus erythematosus

Pneumocystis jeroveci pneumonia (PCP) is an opportunistic infection which occurs mostly in the immune-deficiency host. Although PCP infected systemic lupus erythematosus (SLE) patient carries poor outcome, no standard guideline for prevention has been established. The aim of our study is to identify the risk factors which will indicate the PCP prophylaxis in SLE. This is a case control study. A search of Ramathibodi hospital's medical records between January 1994 and March 2004, demonstrates 15 cases of SLE with PCP infection. Clinical and laboratory data of these patients were compared to those of 60 matched patients suffering from SLE but no PCP infection. Compared to SLE without PCP, those with PCP infection have significantly higher activity index by MEX-SLEDAI (13.6 +/- 5.83 vs. 6.73 +/- 3.22) or more renal involvement (86 vs. 11.6%, P < 0.01), higher mean cumulative dose of steroid (49 +/- 29 vs. 20 +/- 8 mg/d, P < 0.01), but lower lymphocyte count (520 +/- 226 vs. 1420 +/- 382 cells/mm(3), P < 0.01). Interestingly, in all cases, a marked reduction in lymphocyte count (710 +/- 377 cells/mm(3)) is observed before the onset of PCP infection. The estimated CD4+ count is also found to be lower in the PCP group (156 +/- 5 vs. 276 +/- 8 cells/mm(3)). Our study revealed that PCP infected SLE patients had higher disease activity, higher dose of prednisolone treatment, more likelihood of renal involvement, and lower lymphocyte count as well as lower CD4+ count than those with no PCP infection. These data should be helpful in selecting SLE patients who need PCP prophylaxis.     

Pneumocystis carinii pneumonia among patients with neoplastic disease.

Pneumocystis carinii pneumonia (PCP) emerged in the 1980s as the most common opportunistic infection among patients with the acquired immunodeficiency syndrome (AIDS). Because of this, the presentation and clinical course of PCP has become well-known to many physicians. However, PCP continues to occur among patients not infected with the human immunodeficiency virus, generally those who receive immunosuppressive therapy as treatment for neoplastic disease. A review from Memorial Sloan-Kettering Cancer has shown that a new group of patients, those receiving corticosteroid therapy for brain neoplasm, are also at risk for the development of PCP and should receive PCP prophylaxis. Previously defined patient groups--people with acute lymphocytic leukemia or allogeneic bone marrow transplantation--also should continue to receive prophylaxis. In addition, the clinical course and outcome of patients with neoplastic disease who develop PCP may differ from those with AIDS and PCP: the disease may be much more fulminant among patients with neoplastic disease, and the mortality rate much higher, approaching 50% in the Memorial Sloan-Kettering Cancer Center series. Wider use of prophylaxis should decrease the frequency of this disease, whereas prompt initiation of therapy in patients with a compatible syndrome should help to improve mortality rates.     

Failure of prophylaxis against PCP in patients with HIV infection

Since the end of the 1980s, primary anti-Pneumocystis carinii pneumonia (PCP) prophylaxis has become a fundamental part of the global AIDS control strategy in industrialized countries. The widespread adoption of anti-PCP chemoprophylaxis has been a key element in prolonging the survival of patients with AIDS. There is general agreement on the need to begin chemoprophylaxis when individual CD4+ cell counts drop below the value of 200/microL. However, PCP still develops in up to 27% of susceptible HIV-infected patients despite regular prophylaxis intake. Failure of chemoprophylaxis may depend on different factors. The choice of the regimen and the patient's compliance to it have been the first variables to be identified, whereas the importance of the residual cellular immune function as complementary protective mechanism against PCP has emerged in subsequent clinical studies. Albeit of limited general concern, issues such as P. carinii drug resistance and defective drug absorption may play some role in prophylaxis failure in selected patients. Regarding the epidemiology of primary and recurrent episodes of PCP, recent studies based on genetic fingerprinting techniques revealed that interhuman transmission of the organism could be more relevant than so far expected, thus raising some concern of the possibility of nosocomial spread among susceptible individuals. The downgrading tendency of immune competence in HIV infection and the related increasing risk of developing PCP make it possible to envisage a two-step chemoprophylactic strategy, with the most effective compound, cotrimoxazole, to be reserved for the last and most risky disease stage, when immune response no longer provides any support for preventing the development of PCP.     

Pneumocystis pneumonia in HIV-1-infected patients

Pneumocystis pneumonia (PCP) is an opportunistic disease that mainly affects patients with a deficiency of cell-mediated immunity, especially acquired immunodeficiency syndrome (AIDS). The incidence of PCP in these patients has declined substantially owing to the widespread use of antiretroviral therapy and PCP prophylaxis. However, PCP is still a major AIDS-related opportunistic infection, particularly in patients with advanced immunosuppression in whom human immunodeficiency virus type 1 (HIV-1) infection remains undiagnosed or untreated. The clinical manifestations, diagnosis, treatment, and prevention of PCP in patients with HIV-1 infection are addressed in this review.     

外周血宏基因组二代测序对肺孢子菌肺炎的诊断价值

目的:研究探讨外周血宏基因组二代测序技术(mNGS)在免疫抑制剂治疗的肾脏疾病患者合并肺孢子菌肺炎(PCP)的诊断价值。方法:选取肾脏疾病接受免疫抑制治疗后合并弥漫性肺部感染、临床拟诊为PCP的患者37例作为观察组,另选取25例临床确诊为其他病原导致肺部感染的患者作为对照。使用mNGS检测患者外周血中的病原种类和序列,评价mNGS对PCP的检测效能,比较mNGS与传统临床诊断PCP方法(真菌G联合乳酸脱氢酶检测)的效能差异。结果:观察组患者送检外周血样本37份,其中35份mNGS检出耶氏肺孢子菌(PJ)序列,敏感度94.59%,特异度100%;31例患者为混合型感染,27例检出病毒序列(19例为巨细胞病毒),8例合并细菌感染。对照组25份血标本PJ序列均为阴性。真菌G联合乳酸脱氢酶检测的敏感度89.19%,特异度56.0%;mNGS的特异度显著高于真菌G联合乳酸脱氢酶检测。结论:mNGS较传统诊断PCP的方法有明显优势,可同时检出混合感染的病原,对免疫抑制合并肺部感染的诊断有重要意义。     

Risk factors for community-acquired pneumonia among persons infected with human immunodeficiency virus

Two hundred eleven adults with human immunodeficiency virus (HIV) infection hospitalized for community-acquired pneumonia, including Pneumocystis carinii pneumonia (PCP; patients), and 192 matched HIV-infected hospitalized patients without pneumonia (controls) were interviewed to determine risk factors for pneumonia. Multivariate logistic regression showed that patients were less likely than controls to have used trimethoprim-sulfamethoxazole (TMP-SMZ) prophylaxis (odds ratio [OR], 0.22; 95% confidence interval [CI], 0.12-0.41) and more likely to have been hospitalized previously with pneumonia (OR, 6.25; CI, 3.40-11.5). Patients were also more likely than controls to have gardened (OR, 2.24; CI, 1.00-5.02) and to have camped or hiked (OR, 4.95; CI, 1.31-18.7), but stratified analysis by etiologic agent showed this association only for PCP. These findings reconfirm the efficacy of TMP-SMZ in preventing community-acquired pneumonia. In addition, hospitalization for pneumonia might represent a missed opportunity to encourage HIV-infected patients to enter into regular medical care and to adhere to prescribed antiretroviral and prophylaxis medications.     

S-adenosylmethionine levels in the diagnosis of Pneumocystis carinii pneumonia in patients with HIV infection.

BACKGROUND: S-adenosylmethionine (AdoMet) is a key molecule involved in methylation reactions and polyamine synthesis. Pneumocystis carinii are unable to synthesize this molecule and have been shown to scavenge this metabolic intermediate from the plasma of rats during active infection. A prior study involving humans strongly suggested that low levels of plasma AdoMet are sensitive and specific indicators of acute infection. METHODS: From March 2004 through January 2006, we collected plasma AdoMet levels from patients with human immunodeficiency virus (HIV) infection and either confirmed Pneumocystis carinii pneumonia (PCP), confirmed pulmonary tuberculosis, or confirmed bacterial pneumonia. We compared levels in patients with PCP with those in patients with other diseases and also monitored changes in levels during treatment of PCP. RESULTS: Initial AdoMet levels were significantly lower in patients with PCP, and there was no overlap between the groups. Among patients with PCP, levels of AdoMet increased with successful treatment. CONCLUSIONS: Measurement of plasma AdoMet levels in patients with HIV infection who have pulmonary infections can identify those with PCP.     

Pneumocystis prophylaxis and survival in patients with advanced human immunodeficiency virus infection treated with zidovudine. The Zidovudine Epidemiology Group.

BACKGROUND--Pneumocystis carinii pneumonia (PCP) is a major cause of morbidity and mortality in persons with advanced human immunodeficiency virus (HIV) infection. We assessed the impact of prophylaxis for PCP on survival in patients with advanced HIV disease who were treated with zidovudine. METHODS--A cohort of 1048 patients with prior PCP (N = 437), another acquired immunodeficiency syndrome-defining diagnosis (N = 168) or acquired immunodeficiency syndrome-related complex (N = 443) and with less than 0.250 x 10(9)/L CD4 cells initiated zidovudine treatment between April 1987 and April 1988. They were then followed up for 24 months. Morbidity and mortality outcomes were assessed every 2 months. A time-dependent, Cox proportional hazards model was used to identify factors associated with new episodes of PCP and with survival. RESULTS--Three hundred thirty-six patients (32%) developed PCP after beginning treatment with zidovudine, with a 24-month actuarial rate of 41%. Patients with prior PCP were more likely to develop PCP during follow up (40%) than those without a history of PCP at entry (27% with PCP at follow-up). Other factors associated with developing PCP were baseline acquired immunodeficiency syndrome vs acquired immunodeficiency syndrome-related complex, and dose interruptions of zidovudine. Thirty-six (17%) of 210 patients who received trimethoprim-sulfamethoxazole prophylaxis developed PCP vs 299 (36%) of 838 who never received trimethoprim-sulfamethoxazole (odds ratio, 0.48). One hundred seven (22%) of 483 patients who ever received aerosol pentamidine prophylaxis developed PCP vs 228 (40%) of 565 who did not receive aerosol pentamidine (odds ratio, 0.55). In a time-dependent Cox proportional hazards analysis, trimethoprim-sulfamethoxazole (relative hazard, 0.21; 95% confidence interval [CI], 0.11 to 0.4) and aerosol pentamidine prophylaxis (relative hazard, 0.25; 95% CI, 0.16 to 0.39) were associated with decreased risk of PCP. Pneumocystis carinii pneumonia during follow-up was strongly associated with death when controlling for other factors (odds ratio, 1.8). For all patients, aerosol pentamidine prophylaxis was associated with a reduced risk of death during follow-up (relative hazard, 0.59; 95% CI, 0.44 to 0.78), while trimethoprim-sulfamethoxazole showed a weaker association (relative hazard, 0.74; 95% CI, 0.54 to 1.1). However, there was a significantly reduced risk of death overall for patients who consistently used trimethoprim-sulfamethoxazole (relative hazard, 0.55; 95% CI, 0.35 to 0.88) or aerosol pentamidine (relative hazard, 0.57; 95% CI, 0.42 to 0.77) and this was most pronounced in patients with a baseline history of PCP. DISCUSSION AND CONCLUSIONS--Pneumocystis carinii pneumonia was common in advanced HIV infection treated with zidovudine. Prophylaxis with trimethoprim-sulfamethoxazole and aerosol pentamidine both were associated with a decreased likelihood of PCP, and consistent use of each was associated with improved survival. Prophylaxis for PCP is associated with prolonged survival for patients with advanced HIV disease.     

HIV-1 seropositive hemophilia A complicated by disseminated intravascular coagulation syndrome and acute pancreatitis during treatment of Pneumocystis carinii pneumonia]

Pneumocystis carinii pneumonia (PCP) is a major opportunistic infection in acquired immunodeficiency syndrome (AIDS) and is treated with co-trimoxazole, pentamidine and others. The severe adverse reactions, including bone marrow suppression, by these therapeutic agents often preclude their continued use. A 14-year-old male HIV-positive hemophilia A patient, who was complicated by disseminated intravascular coagulation syndrome (DIC) following acute pancreatitis during treatment for PCP, was treated with proteinase inhibitors and anticoagulant agents. He was improved and discharged. As pentamidine may cause pancreatitis and develop DIC, it is important that pancreatic enzymes should be carefully followed when this agent administrated. In this case, granulocyte colony-stimulating factor and erythropoietin were effective for the bone marrow suppression, suggesting that importance of these agents for the prophylaxis of other secondary infections during the treatment.     

Pneumocystis jirovecii pneumonia 13 years post renal transplant following a recurrent cytomegalovirus infection

Pneumocystis jirovecii (formerly Pneumocystis carinii) pneumonia (PCP) is a rare but serious infection that usually occurs within a year after solid organ transplantation. PCP may occur after 1 year post transplantation, but the rate is reported to be very low. Studies have shown an association between cytomegalovirus (CMV) infection in solid organ transplant patients and an increased risk of opportunistic infection. This increased risk is thought to be a result of the immunomodulatory effects of the CMV infection. We present a case of PCP infection occurring 13 years after a renal transplantation. This occurred following a recurrent CMV infection while the patient was on low‐dose immunosuppressants.     

Sources of disseminated Mycobacterium avium infection in AIDS

OBJECTIVES: To identify the sources of disseminated Mycobacterium avium complex (MAC) infection in AIDS. METHODS: HIV positive subjects with CD4 counts <100/mm(3) in Atlanta, Boston, New Hampshire and Finland were entered in a prospective cohort study. Subjects were interviewed about potential MAC exposures, had phlebotomy performed for determination of antibody to mycobacterial lipoarabinomannin and for culture. Patient-directed water samples were collected from places of residence, work and recreation. Patients were followed for the development of disseminated MAC. Univariate and multivariate risk factors for MAC were analyzed. RESULTS: Disseminated MAC was identified in 31 (9%) subjects. Significant risks in univariate analysis included prior Pneumocystis carinii pneumonia (PCP) (hazard ratio 1.821), consumption of spring water (4.909), consumption of raw seafood (34.3), gastrointestinal endoscopy (2.894), and showering outside the home (0.388). PCP, showering and endoscopy remained significant in a Cox proportional hazards model. There was no association between M. avium colonization of home water and risk of MAC. In patients with CD4<25, median OD antibody levels to lipoarabinomannin at baseline were 0.054 among patients who did not develop MAC and 0.021 among patients who did develop MAC (P=0.077). CONCLUSIONS: MAC infection results from diverse and likely undetectable environmental and nosocomial exposures. Mycobacterial infection before HIV infection may confer protection against disseminated MAC in advanced AIDS.     

Unusual presentation of pneumocystis pneumonia in an immunocompetent patient diagnosed by open lung biopsy

Pneumocystis pneumonia (PCP) is the most common opportunistic infection in acquired immune deficiency syndrome (AIDS) patients. It is a fungal infection with Pneumocystis jiroveci which can be isolated from bronchoalveolar lavage of healthy subjects. The infection occurs mainly in HIV patients; with CD4 lymphocyte count drop to less than 200 cells/μL. PCP has been reported in non-HIV patients with other risk factors such as immunosuppressive medications, malignancies, and other inflammatory conditions. PCP has been rarely reported in immunocompetent subjects. However, in most of these patients, PCP occurred after a period of acute illness with bacterial pneumonia and antibiotic therapy. In this report, we describe a case of PCP in an immunocompetent patient with nonreactive HIV and no immunosuppressive risk factors. The patient had large pulmonary nodules discovered incidentally on chest film as preoperative evaluation for hip surgery. Bronchoalveolar lavage, transbronchial biopsies (TBB), and computed tomography (CT) guided needle biopsy were all negative for P. jiroveci. PCP diagnosis was made after open lung biopsy and wedge resection. To our knowledge, this is the first case of PCP in immunocompetent patient with negative BAL, TBB and CT guided biopsy. The diagnosis of PCP required open lung biopsy and the patient recovered without complications.     

Real-time PCR is more specific than conventional PCR for induced sputum diagnosis of Pneumocystis pneumonia in immunocompromised patients without HIV infection

Background and objective:   The diagnosis of Pneumocystis pneumonia (PCP) is based on microscopic examination of respiratory specimens. PCP patients without AIDS have a lower burden of P. jiroveci than those with AIDS, which leads to difficulty in detecting the organisms. Although conventional PCR (c-PCR) has been used to detect the DNA, it is frequently positive in patients with colonization. Real-time PCR (r-PCR), a method to detect the DNA quantitatively, might be helpful in distinguishing between infection and colonization. We investigated the utility of real-time PCR in the diagnosis of PCP in non-AIDS patients.
Methods:   Induced sputum samples obtained from 86 non-HIV immunocompromized patients with clinical symptoms of pulmonary infection were evaluated for the presence of Pneumocystis jiroveci -specific DNA using c-PCR and r-PCR. The diagnosis of PCP was confirmed by typical clinical and radiological findings and response to treatment.
Results:   Of the 86 patients, 17 were diagnosed as having PCP. Twenty-eight samples were positive for c-PCR, but the false-positive rate was high (46.4%). Sensitivity, specificity and positive predictive values (PPV) of c-PCR were 88.2%, 81.2% and 53.6%, respectively. Concentrations of the DNA detected by r-PCR were significantly higher in PCP patients than in non-PCP patients. Using 30 copies per tube as a cut-off value for the diagnosis of PCP, the sensitivity (82.4%) of r-PCR was almost equal to c-PCR. Notably, its specificity and PPV were higher than c-PCR (98.6% and 93.3%, respectively).
Conclusions:   r-PCR on induced sputum is more useful for diagnosing PCP than c-PCR in non-HIV immunocompromized patients, especially in terms of distinguishing between colonization and infection.     

双氢青蒿素对卡氏肺孢子虫肺炎大鼠脾细胞凋亡的影响

目的　检测双氢青蒿素对卡氏肺孢子虫肺炎 (PCP)大鼠脾细胞凋亡的影响。方法　以醋酸可的松皮下注射Wis tar大鼠建立PCP动物模型 ,用 60mg/kg双氢青蒿素治疗实验大鼠 ,杀鼠取肺 ,用胶原酶消化法分离其脾细胞 ,用PI和TUNEL染色法检测其凋亡 ,同时设有感染组和正常大鼠对照组。结果　感染组和治疗组大鼠脾细胞凋亡率显著高于正常对照组 ,治疗组大鼠脾细胞凋亡率明显低于感染组。结论　卡氏肺孢子虫感染引起大鼠脾细胞发生凋亡 ,而双氢青蒿素治疗后PCP大鼠脾细胞凋亡降低     

肺孢子菌肺炎药物治疗策略及新药靶点研究进展

肺孢子菌肺炎（Pneumocystis pneumonia,PCP）是免疫功能低下患者严重的机会性感染疾病。目前临床治疗肺孢子菌肺炎常用的一线、二线药物因副作用及特定人群耐受力差等原因而应用受限,亟需开发新药并寻找新的治疗方法以改善PCP患者的预后。本文综述了近些年PCP的药物治疗策略及新的药物靶点研究进展,包括抗真菌药物、免疫调节剂的潜在应用等,以期为PCP的临床治疗提供新的参考。     

Results and complications of fiber bronchoscopy in HIV positive patients

Fibreoptic bronchoscopy is an established diagnostic procedure for HIV-associated pulmonary infections. We retrospectively evaluated the diagnostic effectivity and safety of fibreoptic bronchoscopy with bronchoalveolar lavage (BAL) and transbronchial biopsy (TBB) in 153 patients with late-stage HIV infection and clinical signs of pulmonary infection or abnormal chest radiograph. Bronchoscopy leads to diagnosis in 82.4% and changed therapy in 54%. 45 patients (30%) were found to have pneumocystis carinii pneumonia (PCP), the most common bronchoscopic finding, followed by bacterial lung disease (29.3%). BAL had a sensitivity of 78% for PCP. Diagnostic yield of BAL for PCP was higher in patients without previous treatment (positive results in 82%) with regard to PCP independend of the prior treatment. Serious complication occurred in 22 cases (pneumothorax: 6 (3.9%), bleeding: 12 (7.8%), hypoxaemia: 4 (2.6%)). High serum levels of lactate dehydrogenase (LDH) correlated with pulmonary complications like pneumothorax. Age, sex and kind of pulmonary infection did not influence complication rates. 6 (3.9%) episodes of spontaneous pneumothorax occurred in the further course, 3 of them concurrently with PCP or prior history of PCP. We conclude that fibreoptic bronchoscopy is of great value for diagnosing pulmonary infection in HIV-seropositive patients. TBB provides incremental diagnostic information not available from BAL, especially in patients pretreated with cotrimoxazol or pentamidin. For that reason we believe that TBB should be performed in these patients.     

Outcome of Pneumocystis jirovecii pneumonia diagnosed by polymerase chain reaction in patients without human immunodeficiency virus infection

Background and objective: Pneumonia caused by Pneumocystis jirovecii (PCP) in patients without human immunodeficiency virus (HIV) infection is associated with high mortality. The diagnosis of PCP at our institution is based on detection of DNA using a polymerase chain reaction (PCR) assay. The aim of this study was to describe the clinical manifestations, outcomes and factors associated with mortality due to PCP, as diagnosed by PCR, in patients without HIV infection. Methods: Over a 6‐year period, all HIV‐negative immunocompromised patients suspected of having an opportunistic pulmonary infection underwent diagnostic bronchoscopy. A multigene PCR assay that detects Pneumocystis jirovecii DNA was used for the diagnosis of PCP. Patients were considered to have PCP if they had underlying immunodeficiency, compatible signs and symptoms, abnormal radiological findings, and Pneumocystis jirovecii DNA was detected in a bronchoalveolar lavage fluid sample. Data was collected retrospectively. Results: PCP was diagnosed in 58 patients. The underlying conditions included haematological malignancies (60.3%), solid tumours (17.2%) and immunosuppressive treatment (22.4%). The most common clinical features in patients with PCP were fever (94.6%), dyspnoea (67.2%) and cough (36.2%). The overall in‐hospital mortality was 17.2% (10/58). Mortality was associated with co‐infections, high lactate dehydrogenase levels, female gender, and higher pneumonia severity index and acute physiology and chronic health evaluation III scores. Conclusions: In this study, the mortality of HIV‐negative patients with PCP was low compared with previous reports. We hypothesize that this finding resulted from the increased sensitivity of a PCR‐based assay, as compared with traditional methods, for the diagnosis of PCP in HIV‐negative patients.