Risk factors for Pneumocystis jiroveci pneumonia (PcP) in renal transplant recipients

Risk factors for Pneumocystis jirovecii pneumonia after kidney transplantation: A systematic review and meta-analysis

BACKGROUND AND OBJECTIVE

Pneumocystis jirovecii pneumonia (PJP), an opportunistic infection, often leads to an increase in hospitalization time and mortality rates in kidney transplant (KT) recipients. However, the risk factors associated with PJP in KT recipients remain debatable. Therefore, we conducted this meta-analysis to identify risk factors for PJP, which could potentially help to reduce PJP incidence and improve outcome of KT recipients.

METHODS

We systematically retrieved relevant studies in PubMed, EMBASE, and the Cochrane Library up to November 2023. Pooled odds ratios (ORs) or mean differences (MDs) and the corresponding 95% confidence intervals (CIs) were calculated to assess the impact of potential risk factors on the occurrence of PJP.

RESULTS

27 studies including 42383 KT recipients were included. In this meta-analysis, age at transplantation (MD = 3.48; 95% CI = .56-6.41; p = .02), cytomegalovirus (CMV) infection (OR = 4.00; 95% CI = 2.53-6.32; p = .001), BK viremia (OR = 3.38; 95% CI = 1.70-6.71; p = .001), acute rejection (OR = 3.66; 95% CI = 2.44-5.49; p = .001), ABO-incompatibility (OR = 2.51; 95% CI = 1.57-4.01; p = .001), estimated glomerular filtration rate (eGFR) (MD = -14.52; 95% CI = -25.37- (-3.67); p = .009), lymphocyte count (MD = -.54; 95% CI = -.92- (-.16); p = .006) and anti-PJP prophylaxis (OR = .53; 95% CI = .28-.98; p = .04) were significantly associated with PJP occurrence.

CONCLUSION

Our findings suggest that transplantation age greater than 50 years old, CMV infection, BK viremia, acute rejection, ABO-incompatibility, decreased eGFR and lymphopenia were risk factors for PJP.

Adjunctive glucocorticoid therapy for Pneumocystis jirovecii pneumonia in solid organ transplant recipients: A multicenter cohort, 2015-2020

Solid organ transplant recipients (SOTRs) frequently receive adjunctive glucocorticoid therapy (AGT) for Pneumocystis jirovecii pneumonia (PJP). This multicenter cohort of SOTRs with PJP admitted to 20 transplant centers in Canada, the United States, Europe, and Australia, was examined for whether AGT was associated with a lower rate of all-cause intensive care unit (ICU) admission, 90-day death, or a composite outcome (ICU admission or death). Of 172 SOTRs with PJP (median [IQR] age: 60 (51.5-67.0) years; 58 female [33.7%]), the ICU admission and death rates were 43.4%, and 20.8%, respectively. AGT was not associated with a reduced risk of ICU admission (adjusted odds ratio [aOR] [95% CI]: 0.49 [0.21-1.12]), death (aOR [95% CI]: 0.80 [0.30-2.17]), or the composite outcome (aOR [95% CI]: 0.97 [0.71-1.31]) in the propensity score-adjusted analysis. AGT was not significantly associated with at least 1 unit of the respiratory portion of the Sequential Organ Failure Assessment score improvement by day 5 (12/37 [32.4%] vs 39/111 [35.1%]; P = .78). We did not observe significant associations between AGT and ICU admission or death in SOTRs with PJP. Our findings should prompt a reevaluation of routine AGT administration in posttransplant PJP treatment and highlight the need for interventional studies.

Pneumocystis jirovecii in solid organ transplant recipients: updates in epidemiology, diagnosis, treatment, and prevention

PURPOSE OF REVIEW

This review highlights the epidemiology of Pneumocystis jirovecii pneumonia in solid organ transplant recipients, advancements in the diagnostic landscape, and updates in treatment and prevention.

RECENT FINDINGS

The increasing use of immune-depleting agents in the context of solid organ transplantation has given rise to P. jirovecii pneumonia in this population. The use of prophylaxis has dramatically reduced risk of infection; however, late-onset infections occur after cessation of prophylaxis and in the setting of lymphopenia, advancing patient age, acute allograft rejection, and cytomegalovirus infection. Diagnosis requires respiratory specimens, with PCR detection of Pneumocystis replacing traditional staining methods. Quantitative PCR may be a useful adjunct to differentiate between infection and colonization. Metagenomic next-generation sequencing is gaining attention as a noninvasive diagnostic tool. Trimethoprim-sulfamethoxazole remains the drug of choice for treatment and prevention of Pneumocystis pneumonia. Novel antifungal agents are under investigation.

SUMMARY

P. jirovecii is a fungal opportunistic pathogen that remains a cause of significant morbidity and mortality in solid organ transplant recipients. Early detection and timely treatment remain the pillars of management.

CMV Infection and Lymphopenia: Warning Markers of Pneumocystis Pneumonia in Kidney Transplant Recipients

Pneumocystis pneumonia (PcP) remains life-threatening in kidney transplant recipients (KTR). Our study investigated risk factors one-year before PcP. We conducted a monocentric, case-control study including all KTR at the Dijon University Hospital (France) with a diagnosis of PcP between 2005 and 2022 (cases), and matched control KTR with no history of PcP (3 controls/case). Among all 1,135 KTR, 57 cases (5%) and 169 matched-controls were included. PcP was associated with 18% mortality. Compared to controls, cases were older, with a higher immunological risk, and CMV infection was more frequent in the year preceding the occurrence of PcP (23% vs. 4%; p < 0.001). As early as 1 year before PcP, lymphocyte counts were lower and serum creatinine levels were higher in cases, but immunosuppressive regimens were not significantly different. Multivariable analysis identified lymphocyte count, serum creatinine level, being treated by immunosuppressive therapy other than anti-rejection drugs, and CMV infection in the year preceding the time PcP as independently associated with the occurrence of PcP. PcP was associated with an increased risk of subsequent chronic rejection (27% vs. 3%; p = 0.001) and return to dialysis (20% vs. 3%; p = 0.002). The occurrence of CMV infection and a low lymphocyte count could redefine the indications for continuation or reinitiation of anti-Pneumocystis prophylaxis.

Case Report: Comprehensive Management of Pneumocystis Jiroveci Pneumonia (PJP) and Secondary Infections of Multiple-Drug Resistant Enterobacter cloacae complex and Pseudomonas aeruginosa in a Kidney Transplant Recipient with Sulfonamide Allergies

We report a case of pneumocystis jiroveci pneumonia (PJP) in a 46-year-old woman, who previously underwent kidney transplant for chronic renal failure. She did not receive PJP prophylaxis treatment for the history of sulfonamide allergies. Four months after renal transplantation, the patient had cough, chest tightness, and shortness of breath. Procalcitonin (PCT) (0.06 ng/mL) and C-reactive protein (CRP) (5.33 mg/L) were normal, but the level of 1, 3-β-D-glucan test (G test, 193.89 pg/mL) were elevated. Metagenomics next-generation sequencing (mNGS) using bronchoalveolar lavage fluid (BALF) rapidly and accurately identified P. jiroveci. Through sulfonamide desensitization and sulfamethoxazole-trimethoprim (TMP-SMX) combined with caspofungin (CAS) treatment, PJP was controlled. However, the patients' conditions were worsen for the hospital-acquired secondary pulmonary infection. A second BALF mNGS identified Enterobacter cloacae complex and Pseudomonas aeruginosa carrying carbapenem drug resistance genes, which were confirmed by subsequent culture and antimicrobial susceptibility test within 3 days. Finally, symptoms, such as chest tightness, cough, and shortness of breath, were improved and she was discharged after combined treatment with meropenem (MEM), polymyxin B (PMB), CAS, and TMP-SMX. In this case, mNGS, culture, and drug susceptibility testing were combined to monitor pathogenic microbial and adjust medication. At present, there are no case reports of mNGS use and sulfonamide desensitization in a kidney transplant recipient with sulfonamide allergies.

Unique presentation of late-onset Pneumocystis pneumonia in a pediatric kidney transplant recipient

BACKGROUND

Restrictive lung disease leading to abnormal lung function in kidney transplant recipients is commonly associated with noninfectious complications or medications used for post-transplant immunosuppression. Herein, we report an interesting case of pediatric kidney transplant recipient with weight loss and abnormal spirometry who was diagnosed to have late-onset Pneumocystis pneumonia.

CASE REPORT

A 17-year-old male patient with a history of allergic rhinitis, mild persistent asthma, and deceased donor kidney transplant, performed 18 months prior, presented for routine evaluation of his asthma to the pulmonology clinic. He was clinically asymptomatic except for a weight loss of 8 kg over 6-month period prior to presentation. Patient's spirometry was suggestive of a restrictive pattern and further investigation using a high-resolution computed tomography (HRCT) of the chest showed bilateral diffuse ground-glass reticulonodular opacities with subpleural sparing suggestive of interstitial pneumonitis. A bronchoscopy with bronchoalveolar lavage revealed organisms consistent with Pneumocystis jirovecii on gomori-methenamine-silver (GMS) staining. Beta-d-glucan testing in serum revealed a level of >500 pg/mL (normal 0-59 pg/mL) further supportive of Pneumocystis jirovecii infection. Patient was treated with a 6-week course of trimethoprim-sulfamethoxazole. His weight loss and beta-d-glucan levels improved over a course of 6 months, and he continues to be on trimethoprim-sulfamethoxazole prophylaxis.

CONCLUSION

Late-onset Pneumocystis jirovecii infection in kidney transplant recipients can have an atypical presentation. Treating physicians should consider PJP in the differential diagnosis of unexplained weight loss in pediatric kidney transplant recipients, especially those receiving a large cumulative burden of immunosuppression.

Clinical characteristics and risk factor analysis of Pneumocystis jirovecii pneumonia in patients with CKD: a machine learning-based approach

Patients with chronic kidney disease (CKD) who are being treated with immunosuppressive medications are at risk for developing Pneumocystis jirovecii pneumonia (PCP). We attempted to characterize the clinical aspects of PCP in CKD patients in order to alert high-risk patients with bad prognosis. A retrospective study of CKD patients was conducted from June 2018 to June 2022. Based on PCP diagnostic criteria, these patients were divided into PCP and non-PCP groups. Using univariate and multivariate logistic regression analysis, risk indicators were evaluated, and nomogram and decision tree were developed. Of the CKD patients screened for Pneumocystis carinii nucleic acid, 1512 were included. Two-hundred forty four (16.14%) were diagnosed with PCP. Of the PCP, 88.5% was receiving glucocorticoid (GC) therapy, of which 66.3% received more than 0.5 mg/kg GC. Multivariate analysis showed that membranous nephropathy (OR 2.35, 95% CI 1.45-3.80), immunosuppressive therapy (OR 1.94, 95% CI 1.06-3.69), and ground glass opacity of CT scanning (OR 1.71, 95% CI 1.10-2.65) were associated with increased risk of Pneumocystis carinii infection. The AUC of nomogram based on logistics regression was 0.78 (0.75-0.81). The mortality in patients with PCP was 32.40%. Univariate analysis and decision tree showed that pulmonary insufficiency (PO₂: OR 0.98, 95% CI 0.96-1.00), elevated APTT (OR 1.07, 95% CI 1.04-1.11), and reduced hemoglobin (OR 0.97, 95% CI 0.96-0.98) were associated with poor prognosis. PCP is not rare in CKD patients, particularly in those treated with immunosuppressive therapy. Considering the high mortality of the cases, further studies on the prevention and management of these patients are needed.

Comparison of early and late Pneumocystis jirovecii Pneumonia in kidney transplant patients: the Korean Organ Transplantation Registry (KOTRY) Study

Late Pneumocystis jirovecii pneumonia (PJP) is not rare in the era of universal prophylaxis after kidney transplantation. We aimed to determine the nationwide status of PJP prophylaxis in Korea and compare the incidence, risk factors, and outcomes of early and late PJP using data from the Korean Organ Transplantation Registry (KOTRY), a nationwide Korean transplant cohort. We conducted a retrospective analysis using data of 4,839 kidney transplant patients from KOTRY between 2014 and 2018, excluding patients who received multi-organ transplantation or were under 18 years old. Cox regression analysis was performed to determine risk factors for early and late PJP. A total of 50 patients developed PJP. The number of patients who developed PJP was same between onset before 6 months and onsets after 6 months. There were no differences in the rate, duration, or dose of PJP prophylaxis between early and late PJP. Desensitization, higher tacrolimus dose at discharge, and acute rejection were associated with early PJP. In late PJP, old age as well as acute rejection were significant risk factors. In conclusion late PJP is as common and risky as early PJP and requires individualized risk-based prophylaxis, such as prolonged prophylaxis for old patients with a history of rejection.

Characterization and associated risk factors of Pneumocystis Jirovecii Pneumonia in patients with AIRD: A retrospective study

OBJECTIVES

To explore clinical features of autoimmune inflammatory rheumatic disease (AIRD) patients with Pneumocystis jirovecii pneumonia (PJP) and identify potential risk factors and prognostic factors.

METHODS

AIRD patients who had respiratory symptoms and underwent Pneumocystis jirovecii detection were identified from the database in our department from November 2018 to October 2020. These patients were categorized into PJP and non-PJP groups according to the diagnostic criteria of PJP. Univariate and multivariate analysis were conducted.

RESULTS

173 patients were enrolled and 46 of them had laboratory confirmed PJP. Glucocorticoid (GC) increased the risk of PJP in a dose-dependent manner. In addition, shorter duration of immunosuppressive therapy (IST), combination therapy with CsA, and chronic pulmonary comorbidities were also strongly associated with a higher risk of PJP. Combination of IgM and IgA could well identify AIRD patients with PJP from other AIRD patients with respiratory symptoms, with the optimal cutoff value of -0.96 g/L. 7 of 46 AIRD patients with PJP died (15.2%). Higher level of serum LDH, dyspnea, ARDS, and the presence of extensive ground glass opacity (GGO) in radiologic examinations were more common in deceased patients.

CONCLUSIONS

AIRD patients with high-dose GC treatment, recent initiation of IST, combination therapy with CsA, and history of chronic pulmonary diseases were associated with greater risks of PJP infection. PJP patients with a higher level of serum LDH, dyspnea, moderate and severe ARDS, and the presence of extensive GGO in radiologic examinations had poorer prognosis.

TRIAL REGISTRATION

Chinese Clinical Trial Register; https://www.chictr.org.cn/; ChiCTR2100044095.

Efficacy of Low-Dose Trimethoprim/Sulfamethoxazole for the Treatment of Pneumocystis jirovecii Pneumonia in Deceased Donor Kidney Recipients

Background

Trimethoprim/sulfamethoxazole (TMP-SMX) is considered the first-choice treatment for Pneumocystis jirovecii pneumonia (PJP) in recipients of solid organ transplantation. However, this treatment is associated with various severe adverse events that might not be tolerable for some renal transplant recipients, and the optimal dose remains elusive. The present study assessed the efficacy of low-dose TMP-SMX in recipients of a deceased donor kidney.

Methods

A total of 37 adult deceased donor kidney recipients who suffered PJP between January 2015 and June 2020 were included. The survival rates of the patients and grafts, the rate of invasive ventilation, and adverse events, including gastrointestinal discomfort, hematologic side effects, hyperkalemia, and renal function impairments, were assessed.

Results

The patient and graft survival rates were both 100%. Two patients (5.4%) required invasive ventilation. Eight patients (21.6%) reported gastrointestinal discomfort, but none required dose reduction or discontinued treatment. The frequencies of hematologic side effects, hyperkalemia and impaired kidney function were 5.4% (2/37), 2.7% (1/37), and 2.7% (1/37), respectively.

Conclusion

Optimization of TMP-SMX dose may reduce the risk of adverse events without compromising efficacy for the treatment of PJP in deceased donor kidney recipients.

Characteristics and risk factors for Pneumocystis jirovecii pneumonia in patients with idiopathic membranous nephropathy

Pneumocystis jirovecii pneumonia (PCP) is a life-threatening opportunistic infection in idiopathic membranous nephropathy (IMN) patients, who are treated with immunosuppressive drugs. However, the risk factors of infection and their prognosis are rarely investigated. We aimed to characterize the clinical manifestations of PCP in patients with IMN, and to understand their risk factors, so that we can provide early warnings to patients with high risk and potential poor prognosis. We conducted a retrospective observational study of IMN patients in a referral center in China, from Jan 2012 to Dec 2018. Clinical and laboratory data were collected separately at the time of IMN and PCP diagnosis. Patients with PCP were matched to those without by gender and age at a ratio of 1:4. The risk factors and prognostic factors were determined by univariate and multivariate logistic regression analysis. A total of 879 patients with IMN were included, with a median follow-up of 267 (interquartile range (IQR) 64,842) days. In total, 26 (2.96%) of them were diagnosed with PCP. The infection rate increased to 3.87% among patients who received corticosteroids, and it further increased to 5.49% in those received over 0.5mg/kg prednisone. Univariate analysis indicated that initial usage of corticosteroids, use of cyclophosphamide, reduced estimated glomerular filtration rate (eGFR), and higher 24-h proteinuria were related to the PCP susceptibility. Multivariate analysis revealed that corticosteroid treatment and reduced eGFR increased the risk of the Pneumocystis jirovecii infection. The case fatality rate of the PCP patients was 23.08%, and increased to 75% among patients requiring invasive ventilation. Univariate analysis indicated that pulmonary insufficiency, invasive ventilation, decreased eGFR, and increased lactate dehydrogenase at presentation were linked to poor prognosis. PCP is not rare in patients with IMN, especially those on corticosteroids, and presented with decreased eGFR. Considering the high case fatality rate, further studies are in need for prevention and management of these patients.

The Changing Landscape of Pneumocystis Jiroveci Infection in Kidney Transplant Recipients: Single-Center Experience of Late-Onset Pneumocystis Pneumonia

BACKGROUND

Pneumocystis jiroveci pneumonia (PCP) is a life-threatening pulmonary infection after kidney transplantation (KTx). Its onset in the current era of modern immunosuppression and of routine use of universal PCP prophylaxis seems to differ from its onset in previous decades in terms of late onset with subtle clinical presentation, indicating a need for increased vigilance.

METHODS

We retrospectively studied all KTx recipients from our center who underwent bronchoscopy and bronchoalveolar lavage (BAL) between 2009 and 2018. Of these, all cases with confirmed PCP any time after the first post-KTx year were included in the analysis.

RESULTS

Among 60 patients with KTx who had undergone bronchoscopy and BAL, 12 cases with late-onset PCP were identified. PCP appeared late at a median of 10.8 (interquartile range, 2.4-15.8) years after transplantation. Patients' mean age was 59 years, and all were receiving stable low-dose immunosuppression. Most of the patients (67%) had received PCP prophylaxis after KTx. Five out of 12 patients (42%) had concomitant cytomegalovirus (CMV) reactivation at the time of PCP. In almost all cases, clinical presentation was mild. Treatment consisted of trimethoprim-sulfamethoxazole (TMP-SMX) and intravenous corticosteroid administration, and concomitant immunosuppression was temporarily reduced or withdrawn. Outcome was generally good. None of the patients developed respiratory insufficiency or required mechanical ventilation. One patient died as a result of sepsis, and 3 more with preexisting advanced chronic kidney disease subsequently lost their grafts.

CONCLUSION

Renal transplant recipients are at risk of late-onset PCP, even at a steady state of low-dose maintenance immunosuppression. Because of its subtle clinical presentation, high suspicion of the disease is warranted. Its early recognition and proper management are essential for a successful outcome.

Pulmonary infections after renal transplantation: a prospective study from a tropical country

Pulmonary infection is a leading cause of morbidity and mortality in renal transplant recipients. In a prospective study, we characterized their epidemiology in a tropical country with high infectious disease burden. Adult renal transplant recipients presenting with pulmonary infections from 2015 to 2017 were evaluated using a specific diagnostic algorithm. 102 pulmonary infections occurred in 88 patients. 32.3% infections presented in the first year, 31.4% between 1 and 5, and 36.3% beyond 5 years after transplantation. Microbiological diagnosis was established in 69.6%, and 102 microorganisms were identified. Bacterial infection (29.4%) was most common followed by tuberculosis (23.5%), fungal (20.6%), Pneumocystis jiroveci (10.8%), viral (8.8%), and nocardial (6.9%) infections. Tuberculosis(TB) and bacterial infections presented throughout the post-transplant period, while Pneumocystis (72.7%), cytomegalovirus (87.5%) and nocardia (85.7%) predominantly presented after >12 months. Fungal infections had a bimodal presentation, between 2 and 6 months (33.3%) and after 12 months (66.7%). Four patients had multi-drug resistant(MDR) TB. In 16.7% cases, plain radiograph was normal and infection was diagnosed by a computed tomography imaging. Mortality due to pulmonary infections was 22.7%. On multivariate Cox regression analysis, use of ATG (HR-2.39, 95% CI: 1.20-4.78, P = 0.013), fungal infection (HR-2.14, 95% CI: 1.19-3.84, P = 0.011) and need for mechanical ventilation (9.68, 95% CI: 1.34-69.82, P = 0.024) were significant predictors of mortality in our patients. To conclude, community-acquired and endemic pulmonary infections predominate with no specific timeline and opportunistic infections usually present late. Nocardiosis and MDR-TB are emerging challenges.

The risk factor analysis and treatment experience in pneumocystis jirovecii pneumonia after kidney transplantation

BACKGROUND

Pneumocystis jirovecii pneumonia (PJP) is an opportunistic infection among solid organ transplantation. The occurrence of PJP is dangerous and fatal if there is no early identification and sufficient treatment.

OBJECTIVE

The aim of this study was to evaluate the risk factors and provide appropriate strategies of prophylaxis and treatment for PJP after kidney transplantation in our centre.

PATIENTS/METHODS

From January 2009 to December 2018, a total of 167 kidney transplantation recipients with pneumonia were enrolled, including 47 PJP patients as PJP group and 120 non-PJP patients as control group. The clinical characteristics of the two groups were analysed retrospectively.

RESULTS

Multivariate analysis showed that high total dosage of ATG [OR, 2.03; 95% CI, 1.12-3.68] and cytomegalovirus (CMV) infection were independent risk factors for PJP. Trimethoprim-sulfamethoxazole (TMP-SMX) (1.44 g q6h)-based treatment was used for 2 weeks, and its dosage and course were adjusted according to the therapeutic effect and side effects. Forty-five cases were recovered after 3 months of follow-up, and two patients died of respiratory failure. TMP-SMX (0.48 g/day) prophylaxis was used for 3-6 months and prolonged to 7-8 months after treatment for acute rejection, which reduced the incidence of PJP compared with those without prophylaxis.

CONCLUSION

Our study suggests that the high total dosage of ATG and CMV infection indicate the increased risk of PJP. The strategies of prophylaxis and treatment for PJP after kidney transplantation in our centre were effective.

A Comprehensive Evaluation of Risk Factors for Pneumocystis Jirovecii Pneumonia in Adult Solid Organ Transplant Recipients: a Systematic Review and Meta-Analysis

BACKGROUND

There is no consensus guidance on when to reinitiate Pneumocystis jirovecii pneumonia (PJP) prophylaxis in solid organ transplant (SOT) recipients at increased risk. The 2019 American Society of Transplantation Infectious Diseases Community of Practice (AST IDCOP) guidelines suggested to continue or reinstitute PJP prophylaxis in those receiving intensified immunosuppression for graft rejection, CMV infection, higher dose of corticosteroids, or prolonged neutropenia.

METHODS

A literature search was conducted evaluating all literature from existence through April 22, 2020 using MEDLINE and EMBASE. (PROSPERO: CRD42019134204) RESULTS:: A total of 30 studies with 413 276 SOT recipients were included. The following factors were associated with PJP development: acute rejection (pooled odds ratio (pOR) = 2.35 (1.69, 3.26), study heterogeneity index (I)= 23.4%), cytomegalovirus (CMV)-related illnesses (pOR = 3.14 (2.30, 4.29), I=48%), absolute lymphocyte count < 500 cells/mm (pOR = 6.29[3.56, 11.13], I 0%), BK-related diseases (pOR = 2.59[1.22, 5.49], I 0%), HLA mismatch ≥ 3 (pOR = 1.83 [1.06, 3.17], I= 0%), rituximab use (pOR =3.03 (1.82, 5.04); I =0%) and polyclonal antibodies use for rejection (pOR = 3.92 [1.87, 8.19], I= 0%). On the other hand, sex, CMV mismatch, interleukin-2 inhibitors, corticosteroids for rejection, and plasmapheresis were not associated with developing PJP.

CONCLUSION

PJP prophylaxis should be considered in SOT recipients with lymphopenia, BK-related infections and rituximab exposure in addition to the previously mentioned risk factors in the AST IDCOP guidelines.

Single-Center Retrospective Analysis of Prophylaxis and Treatment of Pneumocystis carinii Pneumonia in Patients with Renal Dysfunction After Renal Transplantation

BACKGROUND Pneumocystis carinii is an opportunistic pathogen that can cause severe lung infections after renal transplantation. Trimethoprim-sulfamethoxazole (TMP-SMX) has been recognized as a first-line treatment for chemoprophylaxis of Pneumocystis carinii pneumonia (PCP). This study aimed to establish a personalized chemoprophylaxis prescription specifically for those recipients with renal insufficiency. MATERIAL AND METHODS This retrospective study included 68 patients with confirmed PCP after renal transplantation. Patients were divided into 2 groups: an abnormal renal function (ARF) group (creatinine ≥1.5 ng/dl; n=37) and a normal renal function (NRF) group (creatinine <1.5 ng/dl; n=31). Clinical characteristics and prognosis of PCP in both groups were compared and analyzed. RESULTS Patients in the ARF group had more prophylaxis after transplantation (15 [40.5%] vs. 2 [6.5%], p=0.047), had more biopsy-proven rejections (10 [27%] vs. 1 [3.2%], p=0.008), and had lower lymphocyte counts (0.6 [05-0.9] vs. 1.1 [0.7-1.6], p<0.01). Renal function after treatment was obviously improved in the ARF group, which had a significant decrease rate in creatinine (-13.2% [-22~4.8%] vs. -4.4% [-12.6~20.9%], p=0.043). CONCLUSIONS PCP prophylaxis regimens for recipients after renal transplantation are still needed regardless of whether the renal functions were normal or abnormal, especially for recipients with persistent lymphopenia or rejection after transplantation.

Severe hypercalcemia preceding a diagnosis of Pneumocystis jirovecii pneumonia in a liver transplant recipient

Background

Incidence of the opportunistic infection Pneumocystis jirovecii pneumonia (PJP) in solid organ transplant patients ranges from 5 to 15% with a mortality of up to 38%.

Case presentation

We present a liver transplant recipient who developed hypoxemic respiratory failure related to PJP soon after treatment for allograft rejection. His presentation was preceded by severe hypercalcemia of 14.6 mg/dL and an ionized calcium of 1.7 mmol/L which remained elevated despite usual medical management and eventually required renal replacement therapy. As approximately 5% of PJP cases have granulomas, here we review the role of pulmonary macrophages and inflammatory cytokines in the pathophysiology of granuloma-mediated hypercalcemia. We also discuss the interpretation of our patient’s laboratory studies, response to medical therapy, and clinical risk factors which predisposed him to PJP.

Conclusions

It is important for clinicians to consider PJP as an etiology of granulomatous pneumonia and non-parathyroid hormone mediated hypercalcemia in chronically immunosuppressed organ transplant recipients for timely diagnosis and management.

Lessons learned from a pneumocystis pneumonia outbreak at a Scottish renal transplant centre

BACKGROUND

Pneumocystis pneumonia (PCP) is an opportunistic infection occurring in renal transplant patients. Over a 14-month period an increase in PCP cases was identified among our renal transplant cohort.

AIM

The outbreak population was studied to identify potential risk factors for the development of PCP.

METHODS

A retrospective analysis of hospital records was carried out, with each case being matched with two case-linked controls. Information was collected on patient demographics, laboratory tests, and hospital visits pre and post development of infection.

FINDINGS

No patients were receiving PCP prophylaxis at the time of infection and mean time from transplantation to developing PCP was 4.7 years (range: 0.51-14.5). The PCP group had a significantly lower mean estimated glomerular filtration rate than the control group (29.3 mL/min/1.73 m² vs 70 mL/min^-1 (P = 0.0007)). Three patients were treated for active cytomegalovirus (CMV) infection prior to PCP diagnosis and two had active CMV at the time of diagnosis compared to none in the control group (P = 0.001). Those who developed PCP were more likely to have shared a hospital visit with another patient who went on to develop PCP; 37% of clinic visits vs 19% (P = 0.014).

CONCLUSION

This study highlights the ongoing risk of opportunistic infection several years after transplantation and adds weight to potential person-to-person Pneumocystis jirovecii transmission. Risk factors have been identified which may highlight those most at risk, enabling targeted rather than blanket long-term PCP prophylaxis.

Prevalence and genotyping of Pneumocystis jirovecii in renal transplant recipients-preliminary report

Pneumocystis jirovecii is an opportunistic fungus occurring in human lungs. The group at highest risk consists of HIV-infected and non-HIV-infected immunosuppressed individuals. In these patients, P. jirovecii infection may lead to Pneumocystis pneumonia; it may, however, persist also in an asymptomatic form. This study aimed to determine the prevalence of P. jirovecii and potential risk factors for infection in a group of renal transplant recipients and to characterize the genetic diversity of this fungus in the studied population. Sputum specimens from 72 patients were tested for presence of P. jirovecii using immunofluorescence microscopy, as well as nested PCR targeting the mtLSU rRNA gene. Genotyping involving analysis of four loci—mtLSU rRNA, CYB, DHPS, and SOD—was used to characterize the diversity of the detected organisms. Pneumocystis DNA was detected in eight (11.11%) patients. It has been shown that low eosinophil count and dual immunosuppressive treatment combining prednisone and calcineurin inhibitors are potential risk factors for colonization. Analysis of genotype distribution showed an association of the wild-type genotype of mtLSU rRNA with lower average age of patients and shorter time after kidney transplantation. Furthermore, CYB 2 genotype was detected only in patients with the ongoing prophylaxis regimen. In conclusion, renal transplant recipients are at risk of Pneumocystis colonization even a long time after transplantation. The present preliminary study identifies specific polymorphisms that appear to be correlated with certain patient characteristics and highlights the need for deeper investigation of these associations in renal transplant recipients.

Pneumocystis jirovecii pneumonia in solid organ transplant recipients: a descriptive analysis for the Swiss Transplant Cohort

BACKGROUND

Descriptive data on Pneumocystis jirovecii pneumonia (PJP) in solid organ transplant recipients (SOTr) in the era of routine Pneumocystis-prophylaxis are lacking.

METHODS

All adult SOTr between 2008 and 2016 were included. PJP was diagnosed based on consensus guidelines. Early-onset PJP was defined as PJP within the first-year-post-transplant.

RESULTS

41/2842 SOTr (1.4%) developed PJP (incidence rate: 0.01/1000 person-days) at a mean of 493-days post-transplant: 21 (51.2%) early vs 20 (48.8%) late-onset PJP. 2465 (86.7%) SOTr received Pneumocystis-prophylaxis for a mean 316 days. PJP incidence was 0.001% and 0.003% (log-rank < 0.001) in SOTr with and without Pneumocystis-prophylaxis, respectively. PJP was an early event in 10/12 (83.3%) SOTr who did not receive Pneumocystis-prophylaxis and developed PJP, compared to those patients who received prophylaxis (11/29, 37.9%; P-value: 0.008). Among late-onset PJP patients, most cases (13/20, 65%) were observed during the 2nd year post-transplant. Age ≥65 years (OR: 2.4, P-value: 0.03) and CMV infection during the first 6 months post-SOT (OR: 2.5, P-value: 0.006) were significant PJP predictors, while Pneumocystis-prophylaxis was protective for PJP (OR: 0.3, P-value: 0.006) in the overall population. Most patients (35, 85.4%) were treated with trimethoprim-sulfamethoxazole for a mean 20.6 days. 1-year mortality was 14.6%.

CONCLUSIONS

In the Pneumocystis-prophylaxis-era, PJP remains a rare post-transplant complication. Most cases occurred post-PJP-prophylaxis-discontinuation, particularly during the second-year-post-transplant. Additional research may help identify indications for Pneumocystis-prophylaxis prolongation.

Genetic diversity of Pneumocystis jirovecii from a cluster of cases of pneumonia in renal transplant patients: Cross-sectional study

Pneumocystis jirovecii can cause severe potentially life-threatening pneumonia (PCP) in kidney transplant patients. Prophylaxis of patients against PCP in this setting is usually performed during 6 months after transplantation. The aim of this study is to describe the molecular epidemiology of a cluster of PCP in renal transplant recipients in Brazil. Renal transplant patients who developed PCP between May and December 2011 had their formalin-fixed paraffin-embedded (FFPE) lung biopsy samples analysed. Pneumocystis jirovecii 23S mitochondrial large subunit of ribosomal RNA (23S mtLSU-rRNA), 26S rRNA, and dihydropteroate synthase (DHPS) genes were amplified by polymerase chain reaction (PCR), sequenced, and analysed for genetic variation. During the study period, 17 patients developed PCP (only four infections were documented within the first year after transplantation) and six (35.3%) died. Thirty FFPE samples from 11 patients, including one external control HIV-infected patient, had fungal DNA successfully extracted for further amplification and sequencing for all three genes. A total of five genotypes were identified among the 10 infected patients. Of note, four patients were infected by more than one genotype and seven patients were infected by the same genotype. DNA extracted from FFPE samples can be used for genotyping; this approach allowed us to demonstrate that multiple P. jirovecii strains were responsible for this cluster, and one genotype was found infecting seven patients. The knowledge of the causative agents of PCP may help to develop new initiatives for control and prevention of PCP among patients undergoing renal transplant and improve routine PCP prophylaxis.

Cytomegalovirus infection and graft rejection as risk factors for pneumocystis pneumonia in solid organ transplant recipients: A systematic review and meta-analysis

A growing number of publications have reported the outbreaks of post-transplant pneumocystis pneumonia (PJP). In most studies, the onset of PJP was beyond 6-12 months of prophylaxis. Cytomegalovirus (CMV) infection and allograft rejection have been repeatedly reported as probable risk factors for post-transplant PJP. In this systematic review and meta-analysis, we determined the pooled effect estimates of these 2 variables as risk factors. Data sources included PUBMED, MEDLINE-OVID, EMBASE-OVID, Cochrane Library, Networked Digital Library of Theses and Dissertations, World Health Organization, and Web of Science. We excluded publications related to hematopoietic stem cell transplantation (HSCT) or Human Immunodeficiency Virus (HIV) patients. Eventually, 15 studies remained for the final stage of screening. Cytomegalovirus infection (OR: 3.30, CI 95%: 2.07-5.26, I² : 57%, P = 0.006) and allograft rejection (OR:2.36, CI95%: 1.54-3.62, I2: 45.5%, P = 0.05) significantly increased the risk of post-transplant PJP. Extended prophylaxis targeting recipients with allograft rejection or CMV infection may reduce the risk of PJP.

Prophylaxis and treatment of Pneumocystis Jirovecii pneumonia after solid organ transplantation

Pneumocystis jirovecii pneumonia (PJP) is an opportunistic infection diagnosed in immunocompromized patients. After solid organ transplantation, early infection has decreased as a result of effective prophylaxis, but late infections and even outbreaks caused by interpatient transmission of pneumocystis by air are present in the SOT community. Different risk factors for PJP have been described and several indications for PJP prophylaxis have to be considered by clinicians in patients even years after transplantation. Diagnosis of PJP is confirmed by microscopy and immunofluorescence staining of bronchial fluid but PCR as well as serum ß-D-Glucan analysis have become increasingly valuable diagnostic tools. Treatment of choice is Trimethoprim/sulfamethoxazole and early treatment improves prognosis. However, mortality of PJP in solid organ transplant patients is still high and many aspects including the optimal management of immunosuppression during PJP treatment require further investigations.

Hypercalcaemia preceding diagnosis of Pneumocystis jirovecii pneumonia in renal transplant recipients

BACKGROUND

The overall incidence of Pneumocystis jirovecii pneumonia (PJP) in solid organ transplant recipients is 5-15%. A timely diagnosis of PJP is difficult and relies on imaging and detection of the organism.

METHODS

We present a case series of four patients displaying hypercalcaemia with an eventual diagnosis of PJP and document the management of the outbreak with a multidisciplinary team approach. We discuss the underlying pathophysiology and previous reports of hypercalcaemia preceding a diagnosis of PJP. We also reviewed the evidence concerning PJP diagnosis and treatment.

RESULTS

Within our renal transplant cohort, four patients presented within 7 months with hypercalcaemia followed by an eventual diagnosis of PJP. We measured their corrected calcium, parathyroid hormone (PTH), 1,25-dihydroxycholecalciferol [1,25-(OH)2D3] and 25-hydroxycholecalciferol [25(OH)D] levels at admission and following treatment of PJP. All four patients diagnosed with PJP were 4-20 years post-transplantation. Three of the four patients demonstrated PTH-independent hypercalcaemia (corrected calcium >3.0 mmol/L). The presence of high 1,25(OH)2D3 and low 25(OH)D levels suggest negation of the negative feedback mechanism possibly due to an extrarenal source; in this case, the alveolar macrophages. All four patients had resolution of their hypercalcaemia after treatment of PJP.

CONCLUSIONS

Given the outbreak of PJP in our renal transplant cohort, and based on previous experience from other units nationally, we implemented cohort-wide prophylaxis with trimethoprim-sulphamethoxazole for 12 months in consultation with our local infectious diseases unit. Within this period there have been no further local cases of PJP.

Prophylactic effect of trimethoprim-sulfamethoxazole for pneumocystis pneumonia in patients with rheumatic diseases exposed to prolonged high-dose glucocorticoids

Objectives

To investigate the efficacy and safety of trimethoprim/sulfamethoxazole (TMP-SMX) as primary prophylaxis for pneumocystis pneumonia (PCP) in patients with rheumatic diseases receiving high-dose steroids.

Methods

The study included 1522 treatment episodes with prolonged (≥4 weeks) high-dose (≥30 mg/day prednisone) steroids in 1092 patients over a 12-year period. Of these, 262 treatment episodes involved TMP-SMX (prophylaxis group) while other episodes involved no prophylaxis (control group). Differences in 1-year PCP incidence and its mortality between the two groups were estimated using Cox regression. To minimise baseline imbalance, propensity score matching was performed and efficacy outcome was mainly assessed in the postmatched population (n=235 in both groups).

Results

During a total of 1474.4 person-years, 30 PCP cases occurred with a mortality rate of 36.7%. One non-fatal case occurred in the prophylaxis group. TMP-SMX significantly reduced the 1-year PCP incidence (adjusted HR=0.07(95% CI 0.01 to 0.53)) and related mortality (adjusted HR=0.08 (95% CI 0.0006 to 0.71)) in the postmatched population. The result of the same analysis performed in the whole population was consistent with that of the primary analysis. Incidence rate of adverse drug reactions (ADR) related to TMP-SMX was 21.2 (14.8–29.3)/100 person-years. Only two serious ADRs (including one Stevens-Johnson syndrome case) occurred. The number needed to treat for preventing one PCP (52 (33–124)) was lower than the number needed to harm for serious ADR (131 (55–∞)).

Conclusion

TMP-SMX prophylaxis significantly reduces the PCP incidence with a favourable safety profile in patients with rheumatic disease receiving prolonged, high-dose steroids.

Risk factors for Pneumocystis jirovecii pneumonia (PJP) in kidney transplantation recipients

Pneumocystis jirovecii pneumonia (PJP) is a potentially life-threatening infection that occurs in immunocompromised patients. The aim of this study was to evaluate risk factors for PJP in kidney transplantation recipients. We conducted a retrospective analysis of patient data from 500 consecutive kidney transplants performed at Severance Hospital between April 2011 and April 2014. Eighteen kidney transplantation recipients (3.6%) were diagnosed with PJP. In the univariate analysis, acute graft rejection, CMV infection, use of medication for diabetes mellitus, and lowest lymphocyte count were associated with PJP. Recipients who experienced acute graft rejection (odds ratio [OR] 11.81, 95% confidence interval [CI] 3.06–45.57, P < 0.001) or developed CMV infection (OR 5.42, 95% CI 1.69–17.39, P = 0.005) had high odds of PJP in multivariate analysis. In the acute graft rejection subgroup, patients treated with anti-thymocyte globulin (ATG) had significantly higher odds of PJP (OR 5.25, 95% CI 1.01–27.36, P = 0.006) than those who were not. Our data suggest that acute graft rejection and CMV infection may be risk factors for PJP in kidney transplant patients. The use of ATG for acute graft rejection may increase the risk of PJP.

Sex differences in transplantation

Sex plays a role in the incidence and progression of a wide variety of diseases and conditions related to transplantation. Additionally, a growing body of clinical and experimental evidence suggests that sex can impact the pharmacokinetics and pharmacodynamics of several commonly used immunosuppressive and anti-infective drugs in transplant recipients. A better understanding of these sex differences will facilitate advances in individualizing treatment for patients and improve outcomes of solid organ transplantation. Here, we provide a review of sex-related differences in transplantation and highlight opportunities for future research directions.

High Pneumocystis jirovecii colonization rate among haemodialysis patients

Haemodialysis patients have been found to have an increased risk of developing Pneumocystis pneumonia (PcP) compared to the control population. To the best of our knowledge, no data are available on pulmonary colonization with Pneumocystis jirovecii in haemodialysis patients; therefore, the aim of this study was to determine the prevalence of pulmonary colonization with P. jirovecii in haemodialysis patients, and to find the related risk factors. Induced sputa of 62 haemodialysis patients were investigated using quantitative polymerase chain reaction for the presence of P. jirovecii. 20.9% of the patients were colonized with P. jirovecii and 46.2% of whom had CD4 cell counts below 400/μl. There was no significant correlation between colonization and time on dialysis treatment. As haemodialysis patients seem to be at higher risk of PcP than the general population, doctors should be aware of the high rate of P. jirovecii colonization amongst them. Furthermore, colonized patients remain a potential source of transmission of P. jirovecii to other patients or to health care workers.

[Infectious diseases in immunocompromised patients]

Immunkompromittierung birgt immer ein erhöhtes Risiko für die Entwicklung infektiöser Komplikationen. Patienten nach solider Organtransplantation sind besonders gefährdet – in dieser Patientengruppe bilden Infektionen die zweithäufigste Todesursache. Prophylaxe und Impfungen sollten daher konsequent eingesetzt werden. Infektionen bei Immunsupprimierten können mit atypischen klinischen Symptomen einhergehen, was die Diagnose und Therapie für den behandelnden Arzt erschwert. Vor allem virale und opportunistische Infektionen stellen dabei eine Herausforderung dar. Umso mehr ist eine Überwachung der Patienten hinsichtlich Infektionserkrankungen notwendig, um frühzeitig die erforderlichen Maßnahmen einleiten zu können.

Underlying renal insufficiency: the pivotal risk factor for Pneumocystis jirovecii pneumonia in immunosuppressed patients with non-transplant glomerular disease

PURPOSES

Data on PCP in patients with glomerular disease are rare. The aim of this study was to assess the predictors of PCP development, the risk factors for mortality and the incidence of acute kidney injury (AKI) when high-dose trimethoprim-sulphamethoxazole (TMP-SMX) was used in patients with non-transplant glomerular disease.

METHODS

Forty-seven patients with PCP, as confirmed by positive results for Pneumocystis jirovecii DNA or Pneumocystis jirovecii cysts tested by a methenamine silver stain between January 1, 2003, and December 30, 2012, were retrospectively investigated. The baseline characteristics of glomerular disease, clinical findings of PCP and renal parameters after treatment were collected. Predictors for PCP development and risk factors for mortality were determined using a multivariate logistic regression analysis.

RESULTS

All PCP patients exclusively received immunosuppressants. Baseline renal insufficiency [estimated glomerular filtration rate (eGFR) <60 mL/min·1.73 m²] was present in 87.23 % of patients. The overall mortality rate was 29.79 %. A pulmonary coinfection and the need for mechanical ventilation were independently associated with PCP mortality. A lower eGFR, lower serum albumin level and a higher percentage of global glomerulosclerosis were independent predictors of PCP in patients with IgA nephropathy receiving immunosuppressants. AKI occurred in 60.47 % of patients who received TMP-SMX. After treatment cessation, 93.75 % of surviving patients showed a recovery of renal function to baseline values.

CONCLUSIONS

PCP is a fatal complication in patients with glomerular disease, and the use of immunosuppressants may be a basic risk factor for this infection. Underlying renal insufficiency and high renal pathology chronicity are the key risk factors for PCP in IgA nephropathy. TMP-SMX therapy remains an ideal choice because of high treatment response and frequently reversible kidney injury.

Vaccine-Induced Immunogenicity and Protection Against Pneumocystis Pneumonia in a Nonhuman Primate Model of HIV and Pneumocystis Coinfection

BACKGROUND

The ubiquitous opportunistic pathogen Pneumocystis jirovecii causes pneumonia in immunocompromised individuals, including human immunodeficiency virus (HIV)-infected individuals, and pulmonary colonization with P. jirovecii is believed to be a cofactor in the development of chronic obstructive pulmonary disease. There is no vaccine for P. jirovecii; however, most adults are seropositive, indicating natural immune priming to this pathogen. We have shown that humoral response to a recombinant subunit of the P. jirovecii protease kexin (KEX1) correlates with protection from P. jirovecii colonization and pneumonia.

METHODS

Here we evaluated the immunogenicity and protective capacity of the recombinant KEX1 peptide vaccine in a preclinical, nonhuman primate model of HIV-induced immunosuppression and Pneumocystis coinfection.

RESULTS

Immunization with KEX1 induced a robust humoral response remained at protective levels despite chronic simian immunodeficiency virus/HIV-induced immunosuppression. KEX1-immunized macaques were protected from Pneumocystis pneumonia, compared with mock-immunized animals (P= .047), following immunosuppression and subsequent natural, airborne exposure to Pneumocystis

CONCLUSIONS

These data support the concept that stimulation of preexisting immunological memory to Pneumocystis with a recombinant KEX1 vaccine prior to immunosuppression induces durable memory responses and protection in the context of chronic, complex immunosuppression.

Pneumocystis pneumonia outbreak among renal transplant recipients at a North American transplant center: Risk factors and implications for infection control

BACKGROUND

Pneumocystis pneumonia is a severe opportunistic fungal infection. Outbreaks among renal transplant recipients have been reported in Europe and Japan, but never in North America.

METHODS

We conducted a retrospective case-control study among adult renal transplant recipients at a Canadian center, using a 3:1 matching scheme. Ten cases and 30 controls were matched based on initial transplantation date, and all patients received prophylaxis with trimethoprim-sulfamethoxazole for 1 year posttransplantation.

RESULTS

The median time between transplantation and infection was 10.2 years, and all patients survived. Compared with controls, case patients had statistically lower estimated glomerular filtration rate (29.3 mL/min vs 66.3 mL/min; P = .028) and lymphopenia (0.51 × 10(9)/L vs 1.25 × 10(9)/L; P = .002). Transmission mapping revealed significant overlap in the clinic and laboratory visits among case vs control patients (P = .0002). One hundred percent of patients (4 out of 4) successfully genotyped had the same strain of Pneumocystis jirovecii.

CONCLUSIONS

Our study demonstrated an outbreak of pneumocystis more than 10 years following initial transplantation, despite using recommended initial prophylaxis. We identified low estimated glomerular filtration rate and lymphopenia as risk factors for infection. Overlapping ambulatory care visits were identified as important potential sources of infection transmission, suggesting that institutions should re-evaluate policy and infrastructure strategies to interrupt transmission of respiratory pathogens.

Immunosuppressant dose reduction and long-term rejection risk in renal transplant recipients with severe bacterial pneumonia

INTRODUCTION

Due to lifelong immunosuppression, renal transplant recipients (RTRs) are at risk of infectious complications such as pneumonia. Severe pneumonia results in respiratory failure and is life‑threatening. We aimed to examine the influence of immunosuppressant dose reduction on RTRs with bacterial pneumonia and respiratory failure.

METHODS

From January 2001 to January 2011, 33 of 1,146 RTRs at a single centre developed bacterial pneumonia with respiratory failure. All patients were treated using mechanical ventilation and aggressive therapies in the intensive care unit.

RESULTS

Average time from kidney transplantation to pneumonia with respiratory failure was 6.8 years. In-hospital mortality rate was 45.5% despite intensive care and aggressive therapies. Logistic regression analysis indicated that a high serum creatinine level at the time of admission to the intensive care unit (odds ratio 1.77 per mg/dL, 95% confidence interval 1.01-3.09; p = 0.045) was a mortality determinant. Out of the 33 patients, immunosuppressive agents were reduced in 17 (51.5%). We found that although immunosuppressant dose reduction tended to improve in-hospital mortality, this was not statistically significant. Nevertheless, during a mean follow-up period of two years, none of the survivors (n = 18) developed acute rejection or allograft necrosis.

CONCLUSION

In RTRs with bacterial pneumonia and respiratory failure, higher serum creatinine levels were a mortality determinant. Although temporary immunosuppressant dose reduction might not reduce mortality, it was associated with a minimal risk of acute rejection during the two-year follow-up. Our results suggest that early immunosuppressant reduction in RTRs with severe pneumonia of indeterminate microbiology may be safe even when pathogens are bacterial in nature.

Management of Pneumocystis jirovecii Pneumonia in Kidney Transplantation to Prevent Further Outbreak

The outbreak of Pneumocystis jirovecii pneumonia (PJP) among kidney transplant recipients is emerging worldwide. It is important to control nosocomial PJP infection. A delay in diagnosis and treatment increases the number of reservoir patients and the number of cases of respiratory failure and death. Owing to the large number of kidney transplant recipients compared to other types of organ transplantation, there are greater opportunities for them to share the same time and space. Although the use of trimethoprim-sulfamethoxazole (TMP-SMX) as first choice in PJP prophylaxis is valuable for PJP that develops from infections by trophic forms, it cannot prevent or clear colonization, in which cysts are dominant. Colonization of P. jirovecii is cleared by macrophages. While recent immunosuppressive therapies have decreased the rate of rejection, over-suppressed macrophages caused by the higher levels of immunosuppression may decrease the eradication rate of colonization. Once a PJP cluster enters these populations, which are gathered in one place and uniformly undergoing immunosuppressive therapy for kidney transplantation, an outbreak can occur easily. Quick actions for PJP patients, other recipients, and medical staff of transplant centers are required. In future, lifelong prophylaxis may be required even in kidney transplant recipients.

Pneumocystis Pneumonia in Solid-Organ Transplant Recipients

Pneumocystis pneumonia (PCP) is well known and described in AIDS patients. Due to the increasing use of cytotoxic and immunosuppressive therapies, the incidence of this infection has dramatically increased in the last years in patients with other predisposing immunodeficiencies and remains an important cause of morbidity and mortality in solid-organ transplant (SOT) recipients. PCP in HIV-negative patients, such as SOT patients, harbors some specificity compared to AIDS patients, which could change the medical management of these patients. This article summarizes the current knowledge on the epidemiology, risk factors, clinical manifestations, diagnoses, prevention, and treatment of Pneumocystis pneumonia in solid-organ transplant recipients, with a particular focus on the changes caused by the use of post-transplantation prophylaxis.

Molecular detection of Pneumocystis jirovecii using polymerase chain reaction in immunocompromised patients with pulmonary disorders in northeast of Iran

Background and Purpose:

Pneumocystis pneumonia, caused by Pneumocystis jirovecii, is a fatal disease threatening patients with AIDS or immunosuppression. Assessment of colonization in these patients is of great significance, since it can lead to severe pulmonary disorders. Considering the scarcity of published reports on Pneumocystis jirovecii isolates from patients in Mashhad, Iran, we aimed to evaluate pneumocystis colonization in individuals with different pulmonary disorders.

Materials and Methods:

We used nested polymerase chain reaction (PCR) method to amplify mitochondrial large subunit-ribosomal ribonucleic acid (mtLSU-rRNA) gene in 60 bronchoalveolar lavage (BAL) samples, obtained from patients, referring to the Department of Internal Medicine (Pulmonary Diseases Section) at Imam Reza Hospital, affiliated to Mashhad University of Medical Sciences, Mashhad, Iran.

Results:

DNA of Pneumocystis jirovecii was detected in 10 out of 60 BAL samples (16.66%) via nested PCR method.

Conclusion:

According to the present findings, the colonization rate of Pneumocystis jirovecii was similar to the rates reported in other similar studies in Iran.

Pneumocystis pneumonia (PCP) and Pneumocystis jirovecii carriage in renal transplantation patients: a single-centre experience

BACKGROUND

The Pneumocystis pneumonia is an increasing problem in transplanted patients: up to 25% suffer from Pneumocystis pneumonia, occurring during the first 6 months after transplantation.

METHODS

From 2001 to 2009, we investigated 21 patients with pneumonia after renal transplantation for the presence of Pneumocystis jirovecii. The laboratory diagnosis was established by Grocott and Giemsa staining methods and Pneumocystis-specific mitochondrial transcribed large subunit nested polymerase chain reaction (PCR). The PCR was also used for the differentiation of Pneumocystis pneumonia from Pneumocystis carriage.

RESULTS

Of 21 patients, 7 had a Pneumocystis pneumonia, 6 were Pneumocystis carriers and 8 patients were negative. Four out of seven Pneumocystis pneumonia patients and two out of six patients with Pneumocystis carriage had a delayed graft function. An acute cytomegalovirus infection after transplantation was not detectable in the patients with Pneumocystis pneumonia, but in three patients with Pneumocystis carriage.

CONCLUSIONS

Pneumocystis pneumonia was present in 33.3% of transplanted patients with suspected pneumonia. An association between acute rejection or co-infections and Pneumocystis pneumonia or carriage in patients after renal transplantation cannot be excluded. In three out of seven Pneumocystis pneumonia patients, an overlapping of hospitalisation times and an onset of Pneumocystis pneumonia 6 months after transplantation was found. Thus, person-to-person transmission seems probable in these cases.

Pneumocystis jirovecii pneumonia in patients with end-stage renal disease: a comparison with the general population

BACKGROUND

Data on occurrence and risk factors for pneumocystis pneumonia (PCP) in patients with end-stage renal disease (ESRD) are sparse.

METHODS

This was a nationwide population-based study assessing occurrence and risk factors for PCP among patients with ESRD and population controls over a 21-year period (1/1 1990 to 31/12 2010). Using Danish registry data, first-time diagnoses of PCP were identified.

RESULTS

We identified 13 296 adult patients with ESRD and 244 255 controls, yielding 63 560 and 2 223 660 person-years of follow-up (PYFU), respectively. Fifty-eight first-time diagnoses of PCP were recorded in the ESRD group. Forty-six episodes occurred among renal transplant recipients (RTx) and 12 among haemodialysis patients (HD), yielding incidence rates of 181 (136-242) and 43.1 (24.5-75.9) per 100 000 PYFU. Compared to population controls, we found incidence rate-ratios of 125.9 (78.4-204) among RTx and 29.9 (14.1-59.7) among HD patients. Risk factors for PCP in RTx were age 50-65 years, age > 65 years, diabetes, polycystic kidney disease and hypertensive kidney disease/nephrosclerosis with an IRR of 2.22 (1.14-4.31), 3.12 (1.35-7.21), 3.44 (1.16-10.2), 4.25 (1.55-11.7) and 3.87 (1.49-10.0), respectively, and more than 36 months of dialysis before transplantation with an IRR of 1.99 (1.03-3.84). Among RTx the risk of PCP was highest during the first 6 months post-transplantation and increased from the beginning (IR1990-94 = 111 (46.3-267) per 100 000 PYFU) towards the end of the study period (IR2005-10 = 299 (203-439)).

CONCLUSION

The PCP risk is substantial in RTx within the first 6 months of transplantation, emphasizing the potential benefit of prophylactic treatment in the early post-transplant period. Importantly, we identified subgroups within the RTx group that require more attention.

Is newer safer? Adverse events associated with first-line therapies for ANCA-associated vasculitis and lupus nephritis

Clinical outcomes in ANCA-associated vasculitis (AAV) and lupus nephritis have improved greatly with treatment regimens containing high-dose glucocorticoids and cyclophosphamide. However, with the use of these medications come significant adverse events, most notably infections, cytopenias, malignancies, and reproductive abnormalities. Multiple recent randomized controlled trials in AAV and lupus nephritis have compared cyclophosphamide-based regimens with agents such as rituximab, mycophenolate mofetil, and azathioprine, with the hope of providing better clinical outcomes with improved safety profiles. Although some of these newer regimens are now considered first-line treatments of these diseases, their adverse event profiles have been disappointingly similar to those of cyclophosphamide-based protocols. Physicians and patients should consider the adverse event profiles generated by these trials in the context of their extensive use in other patient populations, as well as available measures to prevent such events, when choosing the ideal regimen for an individual patient.

Increasing Pneumocystis pneumonia, England, UK, 2000-2010

After an increase in the number of reported cases of Pneumocystis jirovecii pneumonia in England, we investigated data from 2000-2010 to verify the increase. We analyzed national databases for microbiological and clinical diagnoses of P. jirovecii pneumonia and associated deaths. We found that laboratory-confirmed cases in England had increased an average of 7% per year and that death certifications and hospital admissions also increased. Hospital admissions indicated increased P. jirovecii pneumonia diagnoses among patients not infected with HIV, particularly among those who had received a transplant or had a hematologic malignancy. A new risk was identified: preexisting lung disease. Infection rates among HIV-positive adults decreased. The results confirm that diagnoses of potentially preventable P. jirovecii pneumonia among persons outside the known risk group of persons with HIV infection have increased. This finding warrants further characterization of risk groups and a review of P. jirovecii pneumonia prevention strategies.

No recurrence of Pneumocystis jirovecii Pneumonia after solid organ transplantation regardless of secondary prophylaxis

There are no data on the efficacy of secondary prophylaxis against Pneumocystis pneumonia after solid organ transplantation. Therefore, we investigated the rate of recurrence of Pneumocystis pneumonia after solid organ transplantation in a retrospective cohort study. Between 2005 and 2011, a total of 41 recipients recovered from Pneumocystis pneumonia. Of these, 22 (53.7%) received secondary prophylaxis. None of the 41 recipients experienced recurrence of Pneumocystis pneumonia during the follow-up, regardless of secondary prophylaxis.