Increasing Pneumocystis pneumonia, England, UK, 2000-2010

High prevalence of pneumocystis pneumonia in interstitial lung disease: a retrospective study

BACKGROUND

Interstitial lung disease (ILD) is a new risk category for pneumocystis pneumonia (PCP) with a high mortality rate. The definite diagnostic criteria of PCP in ILD patients have not been established until now. The aims of this study were to identify potential risk factors of PCP in patients with ILD, and to evaluate the performance of metagenomic next-generation sequencing (mNGS), CD4 + T cell count, (1-3)-β-D-Glucan (BG) and lactate dehydrogenase (LDH) in the diagnosis of PCP in ILD patients.

METHODS

This is a retrospective, single-center, case-control study. ILD patients who underwent mNGS from December 2018 to December 2022 were included in the study. Based on the diagnosis criteria of PCP, these patients were divided into PCP-ILD and non-PCP-ILD groups. The potential risk factors for PCP occurrence in ILD patients were analysed via logistic regression. The diagnostic efficacy of mNGS was compared with serological biomarkers.

RESULTS

92 patients with ILD were enrolled, 31 of which had a definite PCP and were assigned to the PCP-ILD group while 61 were to the non-PCP-ILD group. The infection rate of PJ in ILD patients was 33.7% (31/92). The history of glucocorticoid therapy, CD4 + T cell count, BG level and traction bronchiectasis on HRCT were associated with PCP occurrence in ILD patients. LDH level did not reach statistical significance in the logistic regression analysis. mNGS was confirmed as the most accurate test for PCP diagnosis in ILD patients.

CONCLUSION

ILD is a new risk group of PCP with high PCP prevalence. Clinicians should pay close attention to the occurrence of PCP in ILD patients who possess the risk factors of previous glucocorticoid therapy, decreased CD4 + T cell count, increased BG level and absence of traction bronchiectasis on HRCT. mNGS showed the most excellent performance for PCP diagnosis in ILD patients. Peripheral blood CD4 + T cell count and BG level are alternative diagnostic methods for PCP in ILD patients. However, the diagnostic value of serum LDH level was limited in ILD patients.

Pneumocystis pneumonia in French intensive care units in 2013-2019: mortality and immunocompromised conditions

PURPOSE

The recent epidemiology of Pneumocystis pneumonia (PCP) requiring intensive care unit (ICU) admission and the associated spectrum of immunocompromising conditions are poorly described.

METHODS

We analyzed all adult PCP cases admitted to French ICUs via the French medical database system (PMSI), over the period from 2013 to 2019.

RESULTS

French ICUs admitted a total of 4055 adult patients with PCP. Among all hospitalized PCP cases, the proportion requiring ICU admission increased from 17.8 in 2014 to 21.3% in 2019 (P < 0.001). The incidence of severe PCP rose from 0.85 in 2013 to 1.32/100,000 adult inhabitants in 2019 (P < 0.0001), primarily due to the proportion of HIV-negative patients that increased from 60.6% to 74.4% (P < 0.0001). Meanwhile, the annual number of severe PCP cases among patients with HIV infection remained stable over the years. In-hospital mortality of severe PCP cases was 28.5% in patients with HIV infection and 49.7% in patients without. Multivariable logistic analysis showed that patients with HIV infection had a lower adjusted risk of death than patients without HIV infection (Odds Ratio [OR]: 0.30, 95% confidence interval [95CI]: 0.17-0.55). Comorbidities or conditions strongly associated with hospital mortality included the patient's age, Simplified Acute Physiologic Score II, congestive heart failure, coagulopathy, solid organ cancer, and cirrhosis. A vast array of autoimmune inflammatory diseases affected 19.9% of HIV-negative patients.

CONCLUSIONS

The number of PCP cases requiring ICU admission in France has risen sharply. While the yearly count of severe PCP cases in HIV-infected patients has remained steady, this rise predominantly affects cancer patients, with a recent surge observed in patients with autoimmune inflammatory diseases, affecting one in five individuals.

MiR-150 levels are related to in-hospital mortality in non-HIV Pneumocystis pneumonia patients

Pneumocystis pneumonia (PCP) is a common opportunistic infection that occurs in immunocompromised patients. Compared with HIV patients, PCP in non-HIV patients tends to follow up a more urgent course and poorer prognosis. Therefore, markers that could predict survival of PCP patients in non-HIV population are of great value. MiRNA-150 has been widely studied in many diseases since it has been identified as a vital regulator of immune cell differentiation and activation. We thus conduct this study aiming to evaluate the prognostic value of miR-150 level in non-HIV PCP. First, the expression levels of miR-150 were compared between PCP patients and healthy volunteers. The miR-150 levels in immune cells were also detected in PCP mouse models. Then the prognostic value of miR-150 was further assessed in another PCP population (n = 72). The expression levels of miR-150 were measured by reverse transcription real-time PCR (RT-PCR) technique. Our data demonstrated significantly decreased miR-150 expression levels in PCP patients and mouse models compared to controls. The miR-150 levels also decreased in various immune cells of PCP mouse models. With a cut-off value of 3.48, the area under the curve, sensitivity, specificity of miR-150 to predicate PCP mortality were 0.845, 68.2% and 96.0%, respectively. In conclusion, miR-150 expression value might serve as a potential biomarker to identify PCP patients at high risk of death.

Dynamic changes in serum (1-3)-β-D-glucan caused by intravenous immunoglobulin infusion: A prospective study

PURPOSE

The purpose of this study was to investigate the dynamic changes in serum (1-3)-β-D-glucan (BDG) caused by intravenous immunoglobulins (IVIG) infusion in adults.

METHODS

This study included patients who received IVIG infusion from October 2021 to October 2022 during hospitalization. We randomly examined two IVIG samples for every patient. Serum samples were collected at nine time points: before (Tpre), immediately (T1-0), 6h (T1-1) and 12h (T1-2) later on the first day; immediately (T2-0) and six hours later (T2-1) on the second day during IVIG infusion, and within three days after IVIG infusion (Ta1, Ta2, and Ta3, respectively). The Friedman test was used for statistical analysis.

RESULTS

A total of 159 serum BDG from 19 patients were included in the analysis. The BDG content of IVIG ranged from 249 pg/ml to 4812 pg/ml. Patients had significantly elevated serum BDG on T1-0 (176 (113, 291) pg/ml, p = 0.002) and Ta1 (310 (199, 470) pg/ml, p < 0.001), compared with Tpre (41 (38, 65) pg/ml). The increments of serum BDG (ΔBDG) were associated with BDG concentration of IVIG (Spearman r = 0.59, p = 0.02). Individuals with abnormal renal function indexes showed higher serum ΔBDG values at Ta1 (403 (207, 484) pg/ml) than patients with normal renal function (172 (85, 316) pg/ml, p = 0.036).

CONCLUSION

Patients who received IVIG had significantly higher serum BDG values. Elevated BDG levels correlate with BDG content of IVIG and abnormal renal function indexes.

The epidemiology of fungal infections in transplant patients

Transplant patients, including solid-organ transplant (SOT) and hematopoietic stem cell transplant (HSCT) recipients, are exposed to various types of complications, particularly rejection. To prevent these outcomes, transplant recipients commonly receive long-term immunosuppressive regimens that in turn make them more susceptible to a wide array of infectious diseases, notably those caused by opportunistic pathogens. Among these, invasive fungal infections (IFIs) remain a major cause of mortality and morbidity in both SOT and HSCT recipients. Despite the continuing improvement in early diagnostics and treatments of IFIs, the management of these infections in transplant patients is still complicated. Here, we provide an overview concerning the most recent trends in the epidemiology of IFIs in SOT and HSCT recipients by describing the prominent yeasts and molds species involved, the timing of post-transplant IFIs and the risk factors associated with their occurrence in these particularly weak populations. We also give special emphasis into basic research advances in the field that recently suggested a role of the global and long-term prophylactic regimen in orchestrating various biological disturbances in the organism and conditioning the emergence of the most adapted fungal strains to the particular physiological profiles of transplant patients.

Slicing through the challenge of maintaining Pneumocystis in the laboratory

Pneumocystis jirovecii is a major fungal pathogen of humans that causes life-threatening lung infections in immunocompromised individuals. Despite its huge global impact upon human health, our understanding of the pathobiology of this deadly fungus remains extremely limited, largely because it is not yet possible to cultivate Pneumocystis in vitro, independently of the host. However, a recent paper by Munyonho et al. offers a major step forward (F. T. Munyonho, R. D. Clark, D. Lin, M. S. Khatun, et al., 2023, mBio 15:e01464-23, https://doi.org/10.1128/mbio.01464-23). They show that it is possible to maintain both the trophozoite and cyst forms of the mouse pathogen, Pneumocystis murina, in precision-cut lung slices for several weeks. Furthermore, they demonstrate that this offers the exciting opportunity to examine potential virulence factors such as possible biofilm formation as well as antifungal drug responses in the lung.

CD40 Expression by B cells is Required for Optimal Immunity to Murine Pneumocystis Infection

CD40-CD40L interactions are critical for controlling Pneumocystis infection. However, which CD40-expressing cell populations are important for this interaction have not been well-defined. We used a cohousing mouse model of Pneumocystis infection, combined with flow cytometry and qPCR, to examine the ability of different populations of cells from C57BL/6 mice to reconstitute immunity in CD40 knockout (KO) mice. Unfractionated splenocytes, as well as purified B cells, were able to control Pneumocystis infection, while B cell depleted splenocytes and unstimulated bone-marrow derived dendritic cells (BMDCs) were unable to control infection in CD40 KO mice. Pneumocystis antigen-pulsed BMDCs showed early, but limited, control of infection. Consistent with recent studies that have suggested a role for antigen presentation by B cells, using cells from immunized animals, B cells were able to present Pneumocystis antigens to induce proliferation of T cells. Thus, CD40 expression by B cells appears necessary for robust immunity to Pneumocystis.

The Development and Evaluation of a Prediction Model for Kidney Transplant-Based Pneumocystis carinii Pneumonia Patients Based on Hematological Indicators

BACKGROUND

This study aimed to develop a simple predictive model for early identification of the risk of adverse outcomes in kidney transplant-associated Pneumocystis carinii pneumonia (PCP) patients.

METHODS

This study encompassed 103 patients diagnosed with PCP, who received treatment at our hospital between 2018 and 2023. Among these participants, 20 were categorized as suffering from severe PCP, and, regrettably, 13 among them succumbed. Through the application of machine learning techniques and multivariate logistic regression analysis, two pivotal variables were discerned and subsequently integrated into a nomogram. The efficacy of the model was assessed via receiver operating characteristic (ROC) curves and calibration curves. Additionally, decision curve analysis (DCA) and a clinical impact curve (CIC) were employed to evaluate the clinical utility of the model. The Kaplan-Meier (KM) survival curves were utilized to ascertain the model's aptitude for risk stratification.

RESULTS

Hematological markers, namely Procalcitonin (PCT) and C-reactive protein (CRP)-to-albumin ratio (CAR), were identified through machine learning and multivariate logistic regression. These variables were subsequently utilized to formulate a predictive model, presented in the form of a nomogram. The ROC curve exhibited commendable predictive accuracy in both internal validation (AUC = 0.861) and external validation (AUC = 0.896). Within a specific threshold probability range, both DCA and CIC demonstrated notable performance. Moreover, the KM survival curve further substantiated the nomogram's efficacy in risk stratification.

CONCLUSIONS

Based on hematological parameters, especially CAR and PCT, a simple nomogram was established to stratify prognostic risk in patients with renal transplant-related PCP.

Pneumocystis jirovecii Pneumonia in a Patient With Localized Mycosis Fungoides Not Receiving Immunosuppressive Treatment

Pneumocystis jirovecii pneumonia (PCP) is the most common opportunistic infection in patients with human immunodeficiency virus (HIV), but it may develop in patients without HIV, whose immune system is suppressed by anticancer or immunosuppressive agents even when indicating normal counts of CD4+ T cells. Mycosis fungoides (MF) is a primary cutaneous T-cell lymphoma, which is believed not to cause immunosuppressive conditions unless it develops leukosis or metastasis or is treated with anticancer drugs or systemic immunosuppressants. Here, we report a case of PCP in a patient with localized MF not receiving immunosuppressive treatment. The patient, a woman in her 70s, presented with persistent dyspnea. High-resolution computed tomography (HRCT) showed diffuse ground-glass opacities in both lungs. Bronchoalveolar lavage fluid was positive for P. jirovecii. Moreover, the cytomegalovirus antigenemia test was positive, whereas tests for anti-HIV and antihuman T-cell lymphotropic virus antibodies were negative. The patient was treated with trimethoprim-sulfamethoxazole, prednisolone, and ganciclovir, which gradually improved the symptoms and diminished diffuse ground-glass opacities on HRCT. This case exemplifies a rare presentation of PCP with mild MF that was not treated with chemotherapy or immunosuppressants. The possible mechanisms for the development of PCP are discussed.

Low-Dose vs Conventional-Dose Trimethoprim-Sulfamethoxazole Treatment for Pneumocystis Pneumonia in Patients Not Infected With HIV: A Multicenter, Retrospective Observational Cohort Study

BACKGROUND

Trimethoprim-sulfamethoxazole (TMP-SMX) is an effective treatment for Pneumocystis jirovecii pneumonia (PCP) in immunocompromised patients with and without HIV infection; however, a high incidence of adverse events has been observed. Low-dose TMP-SMX is a potentially effective treatment with fewer adverse events; however, evidence is limited.

RESEARCH QUESTION

What is the efficacy and safety of low-dose TMP-SMX for non-HIV PCP compared with conventional-dose TMP-SMX after adjusting for patient background characteristics?

STUDY DESIGN AND METHODS

In this multicenter retrospective cohort study, we included patients diagnosed with non-HIV PCP and treated with TMP-SMX between June 2006 and March 2021 at three institutions. The patients were classified into low-dose (TMP < 12.5 mg/kg/d) and conventional-dose (TMP 12.5-20 mg/kg/d) groups. The primary end point was 30-day mortality, and the secondary end points were 180-day mortality, adverse events grade 3 or higher per the Common Terminology Criteria for Adverse Events v5.0, and initial treatment completion rates. Background characteristics were adjusted using the overlap weighting method with propensity scores.

RESULTS

Fifty-five patients in the low-dose group and 81 in the conventional-dose group were evaluated. In the overall cohort, the average age was 70.7 years, and the proportion of women was 55.1%. The average dose of TMP-SMX was 8.71 mg/kg/d in the low-dose group and 17.78 mg/kg/d in the conventional-dose group. There was no significant difference in 30-day mortality (6.7% vs 18.4%, respectively; P = .080) or 180-day mortality (14.6% vs 26.1%, respectively; P = .141) after adjusting for patient background characteristics. The incidence of adverse events, especially nausea and hyponatremia, was significantly lower in the low-dose group (29.8% vs 59.0%, respectively; P = .005). The initial treatment completion rates were 43.3% and 29.6% in the low-dose and conventional-dose groups (P = .158), respectively.

INTERPRETATION

Survival was similar between the low-dose and conventional-dose TMP-SMX groups, and low-dose TMP-SMX was associated with reduced adverse events in patients with non-HIV PCP.

Pneumocystis jirovecii with high probability detected in bronchoalveolar lavage fluid of chemotherapy-related interstitial pneumonia in patients with lymphoma using metagenomic next-generation sequencing technology

BACKGROUND

Previous studies achieved low microbial detection rates in lymphoma patients with interstitial pneumonia (IP) after chemotherapy. However, the metagenomic next-generation sequencing (mNGS) is a comprehensive approach that is expected to improve the pathogen identification rate. Thus far, reports on the use of mNGS in lymphoma patients with chemotherapy-related IP remain scarce. In this study, we summarized the microbial detection outcomes of lymphoma patients with chemotherapy-related IP through mNGS testing of bronchoalveolar lavage fluid (BALF).

METHODS

Fifteen lymphoma patients with chemotherapy-related IP were tested for traditional laboratory microbiology, along with the mNGS of BALF. Then, the results of mNGS and traditional laboratory microbiology were compared.

RESULTS

Of the 15 enrolled patients, 11 received rituximab and 8 were administered doxorubicin hydrochloride liposome. The overall microbial yield was 93.3% (14/15) for mNGS versus 13.3% (2/15) for traditional culture methods (P ≤ 0.05). The most frequently detected pathogens were Pneumocystis jirovecii (12/15, 80%), Cytomegalovirus (4/15, 26.7%), and Epstein-Barr virus (3/15, 20%). Mixed infections were detected in 10 cases. Five patients recovered after the treatment with antibiotics alone without glucocorticoids.

CONCLUSION

Our findings obtained through mNGS testing of BALF suggested a high microbial detection rate in lymphoma patients with IP after chemotherapy. Notably, there was an especially high detection rate of Pneumocystis jirovecii. The application of mNGS in patients with chemotherapy-related IP was more sensitive.

Clinical Characteristics and Outcomes of Pneumocystis jirovecii Pneumonia in Cancer Patients From a Tertiary Care Hospital

Objective To investigate the predisposing factors, disease course, potential complications, role of primary prophylaxis, and overall outcomes of Pneumocystis jirovecii pneumonia (PJP) in cancer patients. Methods The study was conducted at Shaukat Khanum Memorial Cancer Hospital and Research Center, Lahore, Pakistan. We analyzed the medical records of cancer patients diagnosed with PJP from January 2018 to December 2022 and collected data about demographic characteristics, clinical presentation, predisposing factors, treatment, complications, and mortality rates. We used SPSS 20 (IBM Corp., Armonk, NY, USA) for data analysis. Results Out of 84 patients, 59.5% (n=50) were males and most of the patients belonged to the age group 41 to 65 years. Sixty-seven point nine percent (67.9%; n=57) of patients had underlying hematological malignancy, including three bone marrow transplant recipients while 32.2% (n=27) of patients had underlying solid organ malignancy. We also observed the use of corticosteroids, rituximab, and fludarabine as predisposing factors in 15% (n=13), 27% (n=23), and 3.7%(n=03) of patients, respectively. The most common symptoms were dyspnea (88%; n=74), followed by fever (69%; n=58) and cough (69%; n=58). The former one was more prevalent in hematological malignancy patients as compared to the solid organ tumor group (p-value 0.001). We noted respiratory failure (45.2%; n=38), ICU stay (52.38%; n=44), death (32%; n=27), and shock (10.7% n=9) as the most common PJP-related complications. Moreover, all these complications were more frequent in hematological malignancy patients. We also observed that only three patients developed PJP while on adequate primary prophylaxis for this condition. The overall all-cause one-month mortality was 32% (n=27). Conclusion Cancer patients, especially those with hematological malignancies presenting with symptoms suggestive of PJP, need careful evaluation and preemptive treatment as PJP-related mortality is higher in cancer patients. Early diagnosis and treatment in this population can be lifesaving. Moreover, all cancer patients should receive PJP prophylaxis when indicated.

Pneumocystis Pneumonia Infection Following the Initiation of Pembrolizumab Therapy for Lung Adenocarcinoma

Pneumocystis pneumonia (PCP) is an opportunistic infection that presents a ground-glass appearance in the lungs on chest radiography. Interstitial lung disease is a commonly reported adverse effect of immune checkpoint inhibitor (ICI) treatment; however, there are few reports of ICI treatment-associated PCP infection. A 77-year-old man with lung adenocarcinoma was administered pembrolizumab and hospitalized for dyspnea 2 weeks after treatment. Chest computed tomography showed bilateral ground-glass opacities in all lung lobes. PCP was therefore diagnosed, and steroids and sulfamethoxazole-trimethoprim were initiated. Following treatment, the patient's condition improved promptly. This report suggests that ICI treatment can cause PCP infection.

Risk-Benefit Analysis of Primary Prophylaxis Against Pneumocystis Jirovecii Pneumonia in Patients With Rheumatic Diseases Receiving Rituximab

OBJECTIVE

To identify a specific population of patients with rheumatic diseases receiving rituximab treatment for whom the benefit from primary prophylaxis against Pneumocystis jirovecii pneumonia (PJP) outweighs the risk of adverse events (AEs).

METHODS

This study included 818 patients treated with rituximab for rheumatic diseases, among whom 419 received prophylactic trimethoprim/sulfamethoxazole (TMP/SMX) with rituximab, while the remainder did not. Differences in 1-year PJP incidence between the groups were estimated using Cox proportional hazards regression. Risk-benefit assessment was performed in subgroups stratified according to risk factors based on the number needed to treat (NNT) to prevent 1 case of PJP and the number needed to harm (NNH) due to severe AEs. Inverse probability of treatment weighting was applied to minimize the confounding by indication.

RESULTS

During the 663.1 person-years, there were 11 PJP cases, with a mortality rate of 63.6%. Concomitant use of high-dose glucocorticoids (≥30 mg/day of prednisone or equivalent during 4 weeks after rituximab administration) was the most important risk factor. The PJP incidence (per 100 person-years) was 7.93 (95% confidence interval [95% CI] 2.91-17.25) in the subgroup receiving high-dose glucocorticoids compared with 0.40 (95% CI 0.01-2.25) in the subgroup without high-dose glucocorticoid use. Although prophylactic TMP/SMX significantly reduced the overall PJP incidence (HR 0.11 [95% CI 0.03-0.43]), the NNT to prevent 1 case of PJP (146) was higher than the NNH (86). In contrast, the NNT fell to 20 (95% CI 10.7-65.7) in patients receiving concomitant high-dose glucocorticoids.

CONCLUSION

The benefit associated with primary PJP prophylaxis outweighs the risk of severe AEs in patients with rheumatic diseases receiving rituximab and concomitant high-dose glucocorticoid treatment.

Trends in the Epidemiology of Pneumocystis Pneumonia in Immunocompromised Patients without HIV Infection

The increasing morbidity and mortality of life-threatening Pneumocystis pneumonia (PCP) in immunocompromised people poses a global concern, prompting the World Health Organization to list it as one of the 19 priority invasive fungal diseases, calling for increased research and public health action. In response to this initiative, we provide this review on the epidemiology of PCP in non-HIV patients with various immunodeficient conditions, including the use of immunosuppressive agents, cancer therapies, solid organ and stem cell transplantation, autoimmune and inflammatory diseases, inherited or primary immunodeficiencies, and COVID-19. Special attention is given to the molecular epidemiology of PCP outbreaks in solid organ transplant recipients; the risk of PCP associated with the increasing use of immunodepleting monoclonal antibodies and a wide range of genetic defects causing primary immunodeficiency; the trend of concurrent infection of PCP in COVID-19; the prevalence of colonization; and the rising evidence supporting de novo infection rather than reactivation of latent infection in the pathogenesis of PCP. Additionally, we provide a concise discussion of the varying effects of different immunodeficient conditions on distinct components of the immune system. The objective of this review is to increase awareness and knowledge of PCP in non-HIV patients, thereby improving the early identification and treatment of patients susceptible to PCP.

Efficacy of initial caspofungin plus trimethoprim/sulfamethoxazole for severe PCP in patients without human immunodeficiency virus infection

BACKGROUND

The number of pneumocystis pneumonia (PCP) cases is increasing in immunocompromised patients without human immunodeficiency virus infection (HIV), causing serious morbidity with high mortality. Trimethoprim/sulfamethoxazole (TMP/SMZ) monotherapy has limited effectiveness in the treatment of PCP. Clinical data on whether initial caspofungin plus TMP/SMZ for this disease is superior to monotherapy in non-HIV-infected patients are limited. We aimed to compare the clinical effectiveness of these regimens for severe PCP in non-HIV patients.

METHODS

A retrospective study reviewed 104 non-HIV-infected patients with confirmed PCP in the intensive care unit between January 2016 and December 2021. Eleven patients were excluded from the study because TMP/SMZ could not be used due to severe hematologic disorders or clinical data were missing. All enrolled patients were divided into three groups according to different treatment strategies: Group 1 received TMP/SMZ monotherapy, Group 2 received caspofungin combined with TMP/SMZ as first-line therapy, and Group 3 initially received TMP/SMZ monotherapy and later received caspofungin as salvage therapy. The clinical characteristics and outcomes were compared among the groups.

RESULTS

A total of 93 patients met the criteria. The overall positive response rate of anti-PCP treatment was 58.06%, and the overall 90-day all-cause mortality rate was 49.46%. The median APACHE II score was 21.44. The concurrent infection rate was 74.19%, among whom 15.05% (n = 14) of those patients had pulmonary aspergillosis, 21.05% (n = 20) had bacteremia, and 23.65% (n = 22) had CMV infections. The patients who received initial caspofungin combination with TMP/SMZ had the best positive response rate (76.74%) compared to others (p = 0.001). Furthermore, the group that received initial caspofungin combined with TMP/SMZ had a 90-day all-cause mortality rate (39.53%) that was significantly different from that of the shift group (65.51%, p = 0.024), but this rate showed no statistically significant difference compared with that in the monotherapy group (48.62%, p = 0.322). None of the patients had serious adverse events from caspofungin therapy.

CONCLUSIONS

For non-HIV-infected patients with severe PCP, initial combination therapy with caspofungin and TMP/SMZ is a promising first-line treatment option compared with TMP/SMZ monotherapy and combination therapy as salvage therapy.

Current Concepts in the Diagnosis and Management of Pneumocystis Pneumonia in Solid Organ Transplantation

Pneumocystis infection manifests predominantly as an interstitial pneumonia in immunocompromised patients. Diagnostic testing in the appropriate clinical context can be highly sensitive and specific and involves radiographic imaging, fungal biomarkers, nucleic acid amplification, histopathology, and lung fluid or tissue sampling. Trimethoprim-sulfamethoxazole remains the first-choice agent for treatment and prophylaxis. Investigation continues to promote a deeper understanding of the pathogen's ecology, epidemiology, host susceptibility, and optimal treatment and prevention strategies in solid organ transplant recipients.

Analysis of Pneumocystis Transcription Factor Evolution and Implications for Biology and Lifestyle

Pneumocystis jirovecii kills hundreds of thousands of immunocompromised patients each year. Yet many aspects of the biology of this obligate pathogen remain obscure because it is not possible to culture the fungus in vitro independently of its host. Consequently, our understanding of Pneumocystis pathobiology is heavily reliant upon bioinformatic inferences. We have exploited a powerful combination of genomic and phylogenetic approaches to examine the evolution of transcription factors in Pneumocystis species. We selected protein families (Pfam families) that correspond to transcriptional regulators and used bioinformatic approaches to compare these families in the seven Pneumocystis species that have been sequenced to date with those from other yeasts, other human and plant pathogens, and other obligate parasites. Some Pfam families of transcription factors have undergone significant reduction during their evolution in the Pneumocystis genus, and other Pfam families have been lost or appear to be in the process of being lost. Meanwhile, other transcription factor families have been retained in Pneumocystis species, and some even appear to have undergone expansion. On this basis, Pneumocystis species seem to have retained transcriptional regulators that control chromosome maintenance, ribosomal gene regulation, RNA processing and modification, and respiration. Meanwhile, regulators that promote the assimilation of alternative carbon sources, amino acid, lipid, and sterol biosynthesis, and iron sensing and homeostasis appear to have been lost. Our analyses of transcription factor retention, loss, and gain provide important insights into the biology and lifestyle of Pneumocystis. IMPORTANCE Pneumocystis jirovecii is a major fungal pathogen of humans that infects healthy individuals, colonizing the lungs of infants. In immunocompromised and transplant patients, this fungus causes life-threatening pneumonia, and these Pneumocystis infections remain among the most common and serious infections in HIV/AIDS patients. Yet we remain remarkably ignorant about the biology and epidemiology of Pneumocystis due to the inability to culture this fungus in vitro. Our analyses of transcription factor retentions, losses, and gains in sequenced Pneumocystis species provide valuable new views of their specialized biology, suggesting the retention of many metabolic and stress regulators and the loss of others that are essential in free-living fungi. Given the lack of in vitro culture methods for Pneumocystis, this powerful bioinformatic approach has advanced our understanding of the lifestyle of P. jirovecii and the nature of its dependence on the host for survival.

Rising incidence of Pneumocystis pneumonia: A population-level descriptive ecological study in England

OBJECTIVES

Pneumocystis pneumonia (PCP) is an opportunistic infection that causes significant morbidity and mortality in the immunocompromised population. This population is growing and diversifying, yet contemporary epidemiology is lacking. We investigated the population-level incidence of PCP over the past decade.

METHODS

We conducted a descriptive study of all hospital admissions in England from April 2012 to March 2022. PCP episodes, age, median length of stay, gender and episodes of other respiratory fungal infections were collected. Consumption of Trimethoprim-Sulfamethoxazole was obtained between January 2019 and May 2022.

RESULTS

The incidence of PCP increased from 2·2-4·5/100,000 population between 2012/2013 and 2019/2020 (p < 0·0001). There was a drop in 2020/2021 to 2·7/100,000 before returning to 3.9/100,000 in 2021/2022. PCP episodes rose as a proportion of all-cause admissions as well as a proportion of episodes due to other fungal infections. The proportion of PCP patients aged 75+ increased from 14% to 26%. The median length of stay was 13.5 days. Consumption of intravenous Trimethoprim-Sulfamethoxazole increased from 0.24 × 100,000 to 0.30 × 100,000 defined daily doses.

CONCLUSIONS

The incidence of PCP is rising rapidly and represents a significant burden to the healthcare system. Further study into who is at risk of PCP is needed to better determine who should be given prophylaxis.

Emerging and re-emerging fungal threats in Africa

The emergence of deadly fungal infections in Africa is primarily driven by a disproportionately high burden of human immunodeficiency virus (HIV) infections, lack of access to quality health care, and the unavailability of effective antifungal drugs. Immunocompromised people in Africa are therefore at high risk of infection from opportunistic fungal pathogens such as Cryptococcus neoformans and Pneumocystis jirovecii, which are associated with high morbidity, mortality, and related socioeconomic impacts. Other emerging fungal threats include Emergomyces spp., Histoplasma spp., Blastomyces spp., and healthcare-associated multi-drug resistant Candida auris. Socioeconomic development and the Covid-19 pandemic may influence shifts in epidemiology of invasive fungal diseases on the continent. This review discusses the epidemiology, clinical manifestations, and current management strategies available for these emerging fungal diseases in Africa. We also discuss gaps in knowledge, policy, and research to inform future efforts at managing these fungal threats.

Pneumocystis pneumonia in patients with Cushing's syndrome: A French multicenter retrospective study

OBJECTIVE

Pneumocystis pneumonia (PcP) is an opportunistic infection occurring in immunocompromised patients. Cushing's syndrome (CS) impairs the immune system, and several authors have reported PcP in patients with CS. The present study aimed to characterize PcP occurring in a CS context and its management in French tertiary centers, in order to highlight the similarities in clinical presentation and treatment according to whether prophylaxis is implemented or not.

METHODS

This was a multicenter retrospective study conducted in several French University Hospitals and Cancer Centers. Patients with PcP and confirmed CS regardless of etiology were included. We excluded patients with other known causes of acquired immunodeficiency with increased risk of PcP.

RESULTS

Twenty-five patients were included. CS etiology was neoplastic in 84.0% of cases. CS clinical presentation associated predominant catabolic signs (76.0%), hypokalemia (91.7%) and lymphopenia (89.5%). CS was intense in most patients, with mean plasma cortisol levels at diagnosis of 2.424±1.102nmol/L and urinary free cortisol>10× the upper limit of normal in 85.0%. In all patients, PcP onset followed introduction of cortisol blockers, at a median 5.5 days. Patients were treated with 1 to 3 cortisol blockers, mainly metyrapone (88%), which significatively lowered plasma cortisol levels to 667±541nmol/L at the onset of PcP (P<0.001). PcP occurred in 7 patients despite prophylaxis. Finally, 60.0% patients were admitted to intensive care, and 20.0% died of PcP.

CONCLUSION

High mortality in patients with PcP implies that clinicians should be better informed about this rare infectious complication. Prophylaxis remains controversial, requiring comparative studies.

Time to trimethoprim/sulfamethoxazole initiation among patients with rheumatic disease complicated by Pneumocystis jirovecii pneumonia: impact on 90-day mortality

BACKGROUND

Pneumocystis jirovecii pneumonia (PJP) is a life-threatening disease with increasing prevalence in patients with rheumatic disease. Trimethoprim/sulfamethoxazole (TMP/SMX) is an effective treatment for patients with rheumatic disease hospitalized for PJP. This study aimed to describe the 90-day mortality of patients with rheumatic disease complicated by PJP and investigate whether the administration of TMP/SMX after 7 days from initial symptoms correlates with 90-day mortality.

METHODS

We enrolled consecutive patients with rheumatic disease complicated with PJP in our center from August 2018 to August 2021. The participants were classified into two groups according to when TMP/SMX was initiated: early (within the first 7 days) and late (after 7 days). The primary outcome was 90-day PJP-related mortality. Multivariate cox regression and Kaplan-Meier survival analyses were conducted to identify the risk factors for mortality and examine differences in survival between early and late use of TMP/SMX.

RESULTS

Thirty-seven patients with rheumatic disease (median age 50.1 years, 24.3% male) complicated by PJP were enrolled in our study, and 15 (40.5%) patients died at or before 90 days of follow-up. The most common comorbidity was systemic lupus erythematosus (14, 37.8%), followed by inflammatory myopathy (11, 27.9%). Patients in the early group were less likely to require mechanical ventilation (8/27, 29.6% vs. 9/10, 90.0%, P = 0.002), lower doses glucocorticoids (43.2 mg/d vs. 72.2 mg/d, P = 0.039) and had lower mortality (7/27, 25.9% vs. 8/10, 80.0%, P = 0.006) than those in the late group. In the Kaplan-Meier analysis, the survivor probability of the early group was notably higher than that of the late group (P = 0.007). Multivariate cox regression analysis showed that initiation of TMP/SMX after 7 days from admission (hazard ratio [HR]: 5.9, 95% confidence interval [CI]: 1.1-30.4; P = 0.034) and a higher level of lactate dehydrogenase (LDH; HR: 6.0, 95% CI: 1.1-31.8; P = 0.035) were associated with 90-day mortality in patients with rheumatic disease complicated by PJP.

CONCLUSION

Patients with rheumatic disease complicated by PJP had poor prognoses, with mortality rates as high as 40.5%. TMP/SMX initiation after 7 days from initial symptoms and a higher level of serum LDH were significantly associated with increased 90-day mortality.

Risk of Pneumocystis jirovecii Pneumonia among Solid Organ Transplant Recipients: A Population-Based Study

Few studies have comprehensively investigated the occurrence of Pneumocystis jirovecii pneumonia (PJP) among solid organ transplant (SOT) recipients. This study investigated the risk of PJP after organ transplantation. Each patient who underwent SOT was propensity-score-matched with four non-SOT individuals in terms of sex, age, insured salary, urbanization of residence, comorbidities, and year of enrollment. When considering the 3-year follow-up, the patients who had undergone SOT were at higher risk of PJP, with the adjusted odds ratio (aOR) being 17.18 (95% confidence interval (CI): 8.80-33.53). Furthermore, SOT recipients were also at higher PJP risk than the patients without SOT at 6 months, 1 year, and 2 years, with the aOR being 22.64 (95% CI: 7.53-68.11), 26.19 (95% CI: 9.89-69.37), and 23.06 (95% CI: 10.23-51.97), respectively. Patients comorbid with HIV infection, hematological malignancies, or vasculitis were at higher risk (aOR = 59.08, 95% CI = 20.30-171.92), (aOR = 11.94, 95% CI = 5.36-26.61), and (aOR = 21.72, 95% CI = 2.41-195.81), respectively. The recipients of SOT were at higher risk of PJP, and PJP can develop at any stage after transplantation. SOT recipients comorbid with HIV, hematologic malignancies, or vasculitis were at higher PJP risk.

Development and validation of tools for predicting the risk of death and ICU admission of non-HIV-infected patients with Pneumocystis jirovecii pneumonia

Introduction

The mortality rate of non-HIV-infected Pneumocystis jirovecii pneumonia (PCP) is high. This research aimed to develop and validate two clinical tools for predicting the risk of death and intensive care unit (ICU) admission in non-HIV-infected patients with PCP to reduce mortality.

Methods

A retrospective study was conducted at Peking Union Medical College Hospital between 2012 and 2021. All proven and probable non-HIV-infected patients with PCP were included. The least absolute shrinkage and selection operator method and multivariable logistic regression analysis were used to select the high-risk prognostic parameters. In the validation, the receiver operating characteristic curve and concordance index were used to quantify the discrimination performance. Calibration curves were constructed to assess the predictive consistency compared with the actual observations. A likelihood ratio test was used to compare the tool and CURB-65 score.

Results

In total, 508 patients were enrolled in the study. The tool for predicting death included eight factors: age, chronic lung disease, respiratory rate, blood urea nitrogen (BUN), lactate dehydrogenase (LDH), cytomegalovirus infection, shock, and invasive mechanical ventilation. The tool for predicting ICU admission composed of the following factors: respiratory rate, dyspnea, lung moist rales, LDH, BUN, C-reactive protein/albumin ratio, and pleural effusion. In external validation, the two clinical models performed well, showing good AUCs (0.915 and 0.880) and fit calibration plots. Compared with the CURB-65 score, our tool was more informative and had a higher predictive ability (AUC: 0.880 vs. 0.557) for predicting the risk of ICU admission.

Conclusion

In conclusion, we developed and validated tools to predict death and ICU admission risks of non-HIV patients with PCP. Based on the information from the tools, clinicians can tailor appropriate therapy plans and use appropriate monitoring levels for high-risk patients, eventually reducing the mortality of those with PCP.

Metagenomic next-generation sequencing in diagnosing Pneumocystis jirovecii pneumonia: A case report

It remains a huge challenge for clinicians to diagnose Pneumocystis jirovecii pneumonia (PJP) by a conventional method, which leads to delay in diagnosing PJP, accounting for higher mortality in patients with rheumatoid arthritis (RA). A 69-year-old woman, who suffered from RA for years, developed acute respiratory failure. The computed tomography scan showed diffused effusion and ground glass opacity in both lungs, which could not be differentiated from interstitial pneumonia. Metagenomic next-generation sequencing (mNGS) revealed P. jirovecii in both serum and bronchoalveolar lavage fluid with reads per million (RPM) of 17 and 437, while other diagnostic tests did not detect any pathogenic microorganism. The results were verified by quantitative polymerase chain reaction (mtSSU region) against the same samples. The DNA RPM of P. jirovecii declined notably after treatment with trimethoprim/sulfamethoxazole. The patient was discharged without treatment and finally passed away. This case fully highlights the sensitivity of mNGS in early diagnosis of PJP, which is of great significance for prognosis and treatment. Nonetheless, the clinical application of mNGS is worth further standardization and normalization.

Prognostic implication of bronchoalveolar lavage fluid analysis in patients with Pneumocystis jirovecii pneumonia without human immunodeficiency virus infection

Background

The prognostic value of bronchoalveolar lavage (BAL) fluid analysis in non-human immunodeficiency virus (HIV)-infected patients with Pneumocystis jirovecii pneumonia (PJP) has not been well elucidated. We aimed to investigate the prognostic implication of BAL fluid analysis in non-HIV patients with PJP.

Methods

The data of 178 non-HIV patients diagnosed with PJP based on the results of the polymerase chain reaction assay of BAL fluid specimens between April 2018 and December 2020 were retrospectively reviewed. The clinical characteristics, laboratory findings, and BAL fluid analysis results of patients who died within 90 days after hospital admission were compared.

Results

Twenty patients (11.2%) died within 90 days from admission. The neutrophil count in BAL fluid was significantly higher (median 22.0%, interquartile range [IQR] 2.0–46.0% vs. median 6.0%, IQR 2.0–18.0%, P = 0.044), while the lymphocyte count was significantly lower (median 24.0%, IQR 7.0–37.0% vs. median 41.0%, IQR 22.5–60.5%, P = 0.001) in the non-survivor group compared with that in the survivor group. In the multivariate analysis, the C-reactive protein level (odds ratio [OR] 1.093, 95% confidence interval [CI] 1.020–1.170, P = 0.011) and a BAL fluid lymphocyte count of ≤ 30% (OR 3.353, 95% CI 1.101–10.216, P = 0.033) were independently associated with mortality after adjusting for albumin and lactate dehydrogenase levels.

Conclusion

A low lymphocyte count in BAL fluid may be a predictor of mortality in non-HIV patients with PJP.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12890-022-02041-8.

Evolving epidemiology of pneumocystis pneumonia: Findings from a longitudinal population-based study and a retrospective multi-center study in Germany

Background

Pneumocystis pneumonia (PCP) is a life-threatening opportunistic infectious disease of immunocompromised patients. Its incidence has decreased worldwide in the past, but data concerning its recent epidemiology are lacking.

Methods

We retrospectively analyzed all German inpatient cases from January 1, 2014 to December 31, 2019, to describe the recent epidemiology, incidence, clinical course, mortality and underlying diseases of PCP. Simultaneously, we conducted a retrospective multi-center study at two German university hospitals, and analyzed PCP cases treated there to gain deeper insights on the basis of primary patient data.

Findings

The incidence of PCP significantly increased from 2·3 to 2·6 per 100,000 population from 2014 to 2019 (1,857 to 2,172 cases, +17·0%, p < 0·0001), as well as PCP-related deaths (516 to 615 cases, +19·2%, p = 0·011). The spectrum of underlying diseases changed: Risk groups with established chemoprophylaxis for PCP based on international guidelines (HIV, hematologic malignancies, and transplantation) showed a significant decrease in PCP cases and deaths. Others, especially those with solid malignancies, and autoimmune and pulmonary diseases showed a significant increase in case numbers and deaths. Data from the retrospective multi-center study added information regarding prophylaxis and diagnostics of PCP.

Interpretation

The incidence of PCP has reversed its trend, showing a significant increase in mortality on population level. Patients who were not previously considered in prophylactic measures are increasingly affected by PCP. This development deserves further investigation, and additional comprehensive guidelines for the use of chemoprophylaxis in new risk groups are needed.

Funding

Department of Nephrology and Hypertension, University Hospital Schleswig-Holstein, Kiel.

Pneumocystis jirovecii pneumonia in patients with previously untreated acute myeloid leukaemia

BACKGROUND

Several studies in immunocompromised patients, such as those with HIV infection, undergoing cancer chemotherapy or organ transplant, have led to the development of guidelines on the use of prophylaxis to prevent Pneumocystis jirovecii pneumonia (PJP), in these specific conditions. Instead, since the association between PJP and acute myeloid leukaemia (AML) is not clearly defined, the role of prophylaxis in patients with AML is not yet established.

METHODS

We retrospectively analysed 251 consecutive patients with newly diagnosed non-M3-AML, admitted at the Hematology Unit of University Tor Vergata in Rome, during the period 2010-2020. The aim of the study was to evaluate the incidence of PJP among AML patients during their first hospital admission, and to identify subjects at a high risk to develop PJP.

RESULTS

Among 251 consecutive patients with non-M3-AML, 67 bronchoalveolar lavages (BAL) were performed. PJP was proven in 11/67 (16.7%) subjects undergoing BAL (11 males, median age 71 years), with an incidence of 4.3%. The most common reason for BAL execution were radiological findings such as ground-glass opacities (6/11, 55%) and atypical patterns like consolidations and nodules (5/11, 45%). One patient died because of PJP after 11 days of trimethoprim/sulfamethoxazole therapy. In multivariate analysis older age and smoking habit were independent factors significantly associated with PJP (p = .021 and 0.017 respectively).

CONCLUSION

We conclude that PJP infection is not uncommon among patients with AML. If intensive chemotherapy is planned, physicians should be aware of this risk and prophylaxis should be considered, particularly in older patients.

Beta-D-Glucan in Patients with Haematological Malignancies

(1-3)-beta-D-glucan (BDG) is an almost panfungal marker (absent in zygomycetes and most cryptococci), which can be successfully used in screening and diagnostic testing in patients with haematological malignancies if its advantages and limitations are known. The aim of this review is to report the data, particularly from the last 5 years, on the use of BDG in haematological population. Published data report mainly on the performance of the Fungitell™ assay, although several others are currently available, and they vary in method and cut-off of positivity. The sensitivity of BDG for invasive fungal disease (IFD) in haematology patients seems lower than in other populations, possibly because of the type of IFD (lower sensitivity was found in case of aspergillosis compared to candidiasis and pneumocystosis) or the use of prophylaxis. The specificity of the test can be improved by using two consecutive positive assays and avoiding testing in the case of the concomitant presence of factors associated with false positive results. BDG should be used in combination with clinical assessment and other diagnostic tests, both radiological and mycological, to provide maximum information. Good performance of BDG in cerebrospinal fluid (CSF) has been reported. BDG is a useful diagnostic method in haematology patients, particularly for pneumocystosis or initial diagnosis of invasive fungal infections.

No Change of Pneumocystis jirovecii Pneumonia after the COVID-19 Pandemic: Multicenter Time-Series Analyses

Consolidated infection control measures imposed by the government and hospitals during COVID-19 pandemic resulted in a sharp decline of respiratory viruses. Based on the issue of whether Pneumocystis jirovecii could be transmitted by airborne and acquired from the environment, we assessed changes in P. jirovecii pneumonia (PCP) cases in a hospital setting before and after COVID-19. We retrospectively collected data of PCP-confirmed inpatients aged ≥18 years (N = 2922) in four university-affiliated hospitals between January 2015 and June 2021. The index and intervention dates were defined as the first time of P. jirovecii diagnosis and January 2020, respectively. We predicted PCP cases for post-COVID-19 and obtained the difference (residuals) between forecasted and observed cases using the autoregressive integrated moving average (ARIMA) and the Bayesian structural time-series (BSTS) models. Overall, the average of observed PCP cases per month in each year were 36.1 and 47.3 for pre- and post-COVID-19, respectively. The estimate for residuals in the ARIMA model was not significantly different in the total PCP-confirmed inpatients (7.4%, p = 0.765). The forecasted PCP cases by the BSTS model were not significantly different from the observed cases in the post-COVID-19 (−0.6%, 95% credible interval; −9.6~9.1%, p = 0.450). The unprecedented strict non-pharmacological interventions did not affect PCP cases.

Primary prophylaxis for Pneumocystis jirovecii pneumonia in patients receiving rituximab

BACKGROUND

Although previous studies suggested that rituximab increases the risk of Pneumocystis jirovecii pneumonia (PJP), it is uncertain whether its primary prophylaxis for PJP is justified.

RESEARCH QUESTION

Does the benefit of primary prophylaxis for PJP in patients receiving rituximab treatment outweigh the potential risk of the prophylaxis?

STUDY DESIGN AND METHODS

This retrospective study included 3524 patients (hematologic diseases=2500; rheumatic diseases=559; pre/post-solid organ transplantation=465) first exposed to rituximab between 2002 and 2018 in a tertiary referral center in South Korea. Patients were classified into a control group (n=2523) and a prophylaxis group (n=1001) according to the administration of prophylactic TMP-SMX during the first 28 days after the start of rituximab (intention-to-treat analysis). In addition, exposure to TMP-SMX was examined as a time-varying variable (time-varying analysis). Primary outcome was the prophylactic effect of TMP-SMX on the 1-year incidence of PJP. Inverse probability of treatment weights was applied to minimize the baseline imbalance. Secondary outcome included the incidence of adverse drug reactions (ADRs) related to TMP-SMX.

RESULTS

Over 2759.9 person-years, 92 PJP infections occurred, with a mortality rate of 27.2%. The prophylaxis group showed a significantly lower incidence of PJP (adjusted sub-distribution hazard ratio (aSHR), 0.20 [95% CI, 0.10-0.42]) than the control group. This result was consistent with the results of time-varying analysis, in which only one PJP infection occurred during TMP-SMX administration (aSHR, 0.01 [0.003-0.16]). The incidence of adverse drug reactions (ADRs) related to TMP-SMX was 18.1 (14.6-22.2)/100 person-years, and most were of mild-to-moderate severity. Based on ten severe ADRs, the number needed to harm was 101 (61.9-261.1), whereas the number needed to prevent one PJP infection was 32 (24.8-39.4).

INTERPRETATION

TMP-SMX prophylaxis significantly reduces PJP incidence with a tolerable safety profile in patients receiving rituximab treatment.

A Microbial World: Could Metagenomic Next-Generation Sequencing Be Involved in Acute Respiratory Failure?

Background

The usefulness of metagenomic next-generation sequencing (mNGS) in identifying pathogens is being investigated. We aimed to compare the power of microbial identification between mNGS and various methods in patients with acute respiratory failure.

Methods

We reviewed 130 patients with respiratory failure, and 184 specimens including blood, bronchoalveolar lavage fluid (BALF), sputum, pleural effusion, ascitic fluid, and urine were tested by mNGS and conventional methods (culture, PCR). We also enrolled 13 patients to evaluate the power of mNGS and pathogen targets NGS (ptNGS) in microbial identifications. Clinical features and microbes detected were analyzed.

Results

mNGS outperformed the conventional method in the positive detection rate of Mycobacterium tuberculosis (MTB) (OR, ∞; 95% CI, 1–∞; P < 0.05), bacteria (OR, 3.7; 95% CI, 2.4–5.8; P < 0.0001), fungi (OR, 4.37; 95% CI, 2.7–7.2; P < 0.0001), mycoplasma (OR, 10.5; 95% CI, 31.8–115; P = 0.005), and virus (OR, ∞; 95% CI, 180.7–∞; P < 0.0001). We showed that 20 patients (28 samples) were detected with Pneumocystis jirovecii (P. jirovecii) by mNGS, but not by the conventional method, and most of those patients were immunocompromised. Read numbers of Klebsiella pneumoniae (K. pneumoniae), Acinetobacter baumannii (A. baumannii), Pseudomonas aeruginosa (P. aeruginosa), P. jirovecii, cytomegalovirus (CMV), and Herpes simplex virus 1 (HSV1) in BALF were higher than those in other sample types, and the read number of Candida albicans (C. albicans) in blood was higher than that in BALF. We found that orotracheal intubation and type 2 diabetes mellitus (T2DM) were associated with a higher detection rate of bacteria and virus by mNGS, immunosuppression was associated with a higher detection rate of fungi and virus by mNGS, and inflammatory markers were associated with mNGS-positive detection rate of bacteria. In addition, we observed preliminary results of ptNGS.

Conclusion

mNGS outperformed the conventional method in the detection of MTB, bacteria, fungi, mycoplasma, and virus. Orotracheal intubation, T2DM, immunosuppression, and inflammatory markers were associated with a higher detection rate of bacteria, fungi, and virus by mNGS. In addition, ptNGS results were consistent with the detection of abundant bacteria, fungi, and mycoplasma in our specimens.

UK paediatric oncology Pneumocystis jirovecii pneumonia surveillance study

BACKGROUND

Pneumocystis jirovecii pneumonia (PJP) is a serious infective complication of immunosuppressive therapy. There are insufficient data concerning the incidence or mortality rate in children undergoing treatment for malignancies and how these may be influenced by prophylaxis.

OBJECTIVE

Prospective collection of clinical information for all suspected and proven cases of PJP in children with cancer in the UK and Ireland.

DESIGN

A surveillance survey was undertaken using a key contact at each paediatric oncology Principle Treatment Centre (PTC).

MAIN OUTCOME MEASURES

To describe the mortality, outcomes and use of prophylaxis in this at-risk group.

RESULTS

The study confirms that PJP is rare, with only 32 cases detected in the UK over a 2-year period reported from all 20 PTCs. No deaths were directly attributed to PJP, in contrast to previously reported high mortality rates. Breakthrough infection may occur despite prescription of ostensibly adequate prophylaxis with co-trimoxazole; 11 such cases were identified. Six infections occurred in patients for whom prophylaxis was not thought to be indicated. Two infections occurred in patients for whom prophylaxis was specifically omitted due to concerns about potential bone marrow suppression or delayed engraftment.

CONCLUSION

PJP in children treated for malignant disease is rare. Breakthrough infection despite prophylaxis with co-trimoxazole may represent pathogen resistance or non-compliance. Further consideration of the use of PJP prophylaxis during acute myeloid leukaemia and non-Hodgkin's lymphoma treatment is warranted, alongside appraisal of the clinical implications of the possible marrow suppressive effects of co-trimoxazole and its interactions with methotrexate.

Reducing the Risk of Death From Pneumocystis jirovecii Pneumonia After Radical Radiation Therapy to the Lung

AIMS

Lung cancer is the leading cause of cancer death. Radiotherapy given in the curative setting is associated with a 3% risk of death from Pneumocystis jirovecii pneumonia (PJP). Prolonged courses of high-dose steroids also increase the risk of PJP. International guidelines recommend the use of chemoprophylaxis with trimethoprim-sulfamethoxazole for patients at high risk. We assessed the effect of an intervention designed to reduce the impact of PJP.

MATERIALS AND METHODS

Prophylaxis guidelines were introduced in 2016. Case records of patients treated with radical radiotherapy were examined for the periods 2014 to 2015 (pre-intervention) and 2017 to 2018 (post-intervention). In total, 247 patients were treated pre-intervention and 334 post-intervention.

RESULTS

Freedom from PJP death at 1 year was 96% before intervention and 99% after (hazard ratio 0.3, 95% confidence interval 0.1-0.9, P = 0.029). Although the rate of use of chemoprophylaxis according to the guideline rose from 1% to 13% (P = 0.003), the use of high-dose steroids also fell from 35% to 16% (P < 0.00001).

CONCLUSIONS

Reducing radiotherapy-associated infections is an important component of radical treatment in lung cancer. Highlighting chemoprophylaxis guidelines reduced the death rate from PJP, with an associated more judicious use of steroids. Advocating prophylaxis in patients with lymphocyte count <0.6 × 109/l is the next intervention to be studied.

Epidemiological and clinical characteristics of immunocompromised patients infected with Pneumocystis jirovecii in a twelve-year retrospective study from Norway

Background

Pneumocystis pneumonia (PCP) severely menaces modern chemotherapy and immunosuppression. Detailed description of the epidemiology of Pneumocystis jirovecii today is needed to identify candidates for PCP-prophylaxis.

Methods

We performed a 12-year retrospective study of patients with P. jirovecii detected by polymerase chain reaction in Central Norway. In total, 297 patients were included. Comprehensive biological, clinical and epidemiological data were abstracted from patients’ medical records. Regional incidence rates and testing trends were also assessed.

Results

From 2007 to 2017 we found a 3.3-fold increase in testing for P. jirovecii accompanied by a 1.8-fold increase in positive results. Simultaneously, regional incidence rates doubled from 5.0 cases per 100,000 person years to 10.8. A majority of the study population had predisposing conditions other than human immunodeficiency virus (HIV). Hematological (36.0%) and solid cancers (25.3%) dominated. Preceding corticosteroids were a common denominator for 72.1%. Most patients (74.4%) presented with at least two cardinal symptoms; cough, dyspnea or fever. Main clinical findings were hypoxia, cytopenias and radiological features consistent with PCP. A total of 88 (29.6%) patients required intensive care and 121 (40.7%) suffered at least one complication. In-hospital mortality was 21.5%. Three patients (1.0%) had received prophylaxis.

Conclusions

P. jirovecii is re-emerging; likely due to increasing immunosuppressants use. This opportunistic pathogen threatens the life of heterogenous non-HIV immunosuppressed populations currently at growth. Corticosteroids seem to be a major risk factor. A strategy to increase prophylaxis is called for.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-021-06144-1.

Rapid and precise diagnosis of pneumonia coinfected by Pneumocystis jirovecii and Aspergillus fumigatus assisted by next-generation sequencing in a patient with systemic lupus erythematosus: a case report

Background

Pneumocystis jirovecii and Aspergillus fumigatus, are opportunistic pathogenic fungus that has a major impact on mortality in patients with systemic lupus erythematosus. With the potential to invade multiple organs, early and accurate diagnosis is essential to the survival of SLE patients, establishing an early diagnosis of the infection, especially coinfection by Pneumocystis jirovecii and Aspergillus fumigatus, still remains a great challenge.

Case presentation

In this case, we reported that the application of next -generation sequencing in diagnosing Pneumocystis jirovecii and Aspergillus fumigatus coinfection in a Chinese girl with systemic lupus erythematosus (SLE). Voriconazole was used to treat pulmonary aspergillosis, besides sulfamethoxazole and trimethoprim (SMZ-TMP), and caspofungin acetate to treat Pneumocystis jirovecii infection for 6 days. On Day 10 of admission, her chest radiograph displayed obvious absorption of bilateral lung inflammation though the circumstance of repeated fever had not improved. Unfortunately, the patient discharged from the hospital since the financial burden, and during the follow-up, it was documented the patient died within one week after discharge.

Conclusions

This successful application of the next generation sequencing assisting the rapid diagnosis of Pneumocystis jirovecii and Aspergillus fumigatus coinfection provides a new perspective in the clinical approach against the systematic fungi infections and highlights the potential of this technique in rapid etiological diagnosis.

Risk Factors of Mortality From Pneumocystis Pneumonia in Non-HIV Patients: A Meta-Analysis

Background: We performed a meta-analysis to systematically review the risk factors of mortality from non-HIV-related Pneumocystis pneumonia (PcP) and provide the theoretical basis for managing non-HIV-related PcP.

Methods: PubMed, Embase, Web of Science, the Cochrane Library and CNKI databases were searched. A meta-analysis of the risk factors of mortality from non-HIV-related PcP was conducted.

Results: A total of 19 studies and 1,310 subjects were retrieved and included in the meta-analysis, including 485 and 825 patients in the non-survivor and survivor groups, respectively. In the primary analysis, age, concomitant with other pulmonary diseases at diagnosis of PcP, solid tumors, cytomegalovirus(CMV) co-infection, lactate dehydrogenase (LDH), lymphocyte count, invasive ventilation during hospitalization, and pneumothorax were associated with mortality from non-HIV-related PcP, whereas sex, albumin, PcP prophylaxis, use of corticosteroids after admission, and time from onset of symptoms to treatment were not associated with mortality from non-HIV-related PcP.

Conclusions: The mortality rate of non-HIV-infected patients with PcP was still high. Age, concomitant with other pulmonary diseases at diagnosis of PcP, solid tumors, CMV co-infection, LDH, lymphocyte count, invasive ventilation during hospitalization, and pneumothorax were risk factors of mortality from non-HIV-related PcP. Improved knowledge of prognostic factors is crucial to guide early treatment.

Six-month risk of Pneumocystis pneumonia following acute cellular rejection: A case-control study in solid organ transplant recipients

BACKGROUND

Solid organ transplant (SOT) recipients are at risk of Pneumocystis pneumonia (PCP). PCP is associated with significant morbidity and mortality. The effect of acute T cell-mediated rejection (TCMR) on post-transplant PCP has not been determined yet.

METHODS

In this case-control study, we estimated the risk of PCP following acute TCMR during a lookback period of 180 days. We also determined the effects of contributing factors such as CMV infection.

RESULTS

We compared 15 SOT (8 kidney, 4 heart, 2 liver, and 1 kidney-pancreas) recipients with PCP with 60 matched recipients who did not develop PCP (control group) during the study period (December 2013 to February 2016). PCP occurred after a complete course of prophylaxis (ie, late-onset PCP) in 60% of patients. Patients with PCP frequently required intensive care unit (ICU) admission (73.3%). Post-transplant PCP was associated with considerable allograft loss (53.4%) and mortality (26.7%). In the 6-month lookback period, acute TCMR (OR: 13.1, 95% CI: 3.2, 53.2), and CMV infection (OR: 15.1,95% CI: 4.0, 53.2.1) were significantly associated with post-transplant PCP.

CONCLUSIONS

Post-transplant PCP is associated with substantial risk of ICU admission, allograft failure, and mortality. Anti-Pneumocystis prophylaxis for at least 6 months following acute TCMR may reduce the risk.

Risk factors associated with increased discontinuation rate of trimethoprim-sulfamethoxazole used as a primary prophylaxis for Pneumocystis pneumonia: A retrospective cohort study

BACKGROUND

The use of trimethoprim-sulfamethoxazole (TMP-SMX) for Pneumocystis pneumonia (PcP) prophylaxis is often discontinued owing to adverse drug reactions. Half-dosage of TMP-SMX (40/200 mg daily) is considered more tolerable than the conventional dosage (80/400 mg daily). However, patient background characteristics that are associated with the discontinuation of TMP-SMX prophylaxis and suitable for reduced dosage remain unclear. In this study, we aimed to identify the risk factors for the discontinuation of and efficacy of different doses of TMP-SMX prophylaxis in patients with creatinine clearance higher than 30 mL/min.

METHODS

We retrospectively evaluated 318 immunocompromised non-human immunodeficiency virus (HIV)-infected patients (194 men and 124 women; median age, 68.5 [interquartile range, 59-75] years) who underwent TMP-SMX therapy as a primary PcP prophylaxis between July 2014 and August 2019. The patients were segregated into two groups on the basis of dosage: single-strength (SS; n = 244) and half-strength (HS; n = 74) groups. We evaluated PcP occurrence, TMP-SMX discontinuation rate, and discontinuation-related risk factors in these groups.

RESULTS

PcP did not occur in either group. The univariate and multivariate Cox proportional hazards models revealed that the SS dosage and renal function (e.g. serum creatinine and creatinine clearance) were independently associated with prophylaxis discontinuation. At 24 weeks, the HS group presented significantly lower discontinuation rates than the SS group (P = 0.019, log-rank test). In the SS group, patients with mild renal impairment (e.g. serum creatinine ≥0.78 mg/dL or creatinine clearance ≤64.26 mL/min) presented significantly higher TMP-SMX discontinuation rates than those without such an impairment (P < 0.05, log-rank test with Bonferroni correction). This difference was not significant in the HS group.

CONCLUSION

Mild renal impairment might increase the risk of discontinuation of conventional TMP-SMX prophylaxis. In patients with a mild renal impairment, the HS dosage may improve tolerability while maintaining prophylactic efficacy.

Long-read sequencing based clinical metagenomics for the detection and confirmation of Pneumocystis jirovecii directly from clinical specimens: A paradigm shift in mycological diagnostics

The advent of next generation sequencing technologies has enabled the characterization of the genetic content of entire communities of organisms, including those in clinical specimens, without prior culturing. The MinION from Oxford Nanopore Technologies offers real-time, direct sequencing of long DNA fragments directly from clinical samples. The aim of this study was to assess the ability of unbiased, genome-wide, long-read, shotgun sequencing using MinION to identify Pneumocystis jirovecii directly from respiratory tract specimens and to characterize the associated mycobiome. Pneumocystis pneumonia (PCP) is a life-threatening fungal disease caused by P. jirovecii. Currently, the diagnosis of PCP relies on direct microscopic or real-time quantitative polymerase chain reaction (PCR) examination of respiratory tract specimens, as P. jirovecii cannot be cultured readily in vitro. P. jirovecii DNA was detected in bronchoalveolar lavage (BAL) and induced sputum (IS) samples from three patients with confirmed PCP. Other fungi present in the associated mycobiome included known human pathogens (Aspergillus, Cryptococcus, Pichia) as well as commensal species (Candida, Malassezia, Bipolaris). We have established optimized sample preparation conditions for the generation of high-quality data, curated databases, and data analysis tools, which are key to the application of long-read MinION sequencing leading to a fundamental new approach in fungal diagnostics.

Diagnostic evaluation of serum (1, 3)-β-d-glucan levels using the Fungitec G-Test MK kit for Pneumocystis jirovecii pneumonia (PCP) in non-HIV patients

Pneumocystis jirovecii pneumonia (PCP) is an opportunistic and life-threatening pulmonary infection with an increasing prevalence among individuals who are human immunodeficiency virus (HIV)-negative. Evidence regarding diagnostic testing of PCP in this patient population is insufficient. We evaluated the performance of serum (1, 3)-β-d-glucan (BDG) using the Fungitec G-test MK kit for diagnosing PCP in non-HIV patients. We retrospectively analyzed data from 219 non-HIV adult patients who underwent bronchoscopy and were tested for P. jirovecii DNA by PCR using lavage samples from the lower respiratory tract. Fifty PCP patients and 125 non-PCP patients were included. The most common underlying diseases were malignancies and systemic autoimmune diseases. Using the serum BDG Fungitec G-test MK test to diagnose PCP, the area under the receiver operating characteristic curve (AUC) was 0.924, whereas the modified cut-off value of 36.6 pg/mL had a sensitivity and specificity of 92.0% and 84.8%, respectively. The AUC for patients with systemic autoimmune diseases was 0.873, and the accuracy of serum BDG test declined when using methotrexate (MTX). In conclusion, the serum BDG test was useful for diagnosing PCP in non-HIV patients; however, the results should be carefully interpreted in case of MTX administration.

LAY SUMMARY

The Fungitec G-test MK kit for measuring serum (1, 3)-β-d-glucan (BDG) levels had a sufficient diagnostic performance for Pneumocystis jirovecii pneumonia (PCP) in human immunodeficiency virus-negative patients. However, the results should be carefully interpreted in case of MTX administration.

Blood urea nitrogen-to-serum albumin ratio and A-DROP are useful in assessing the severity of Pneumocystis pneumonia in patients without human immunodeficiency virus infection

INTRODUCTION

There is an increasing incidence of Pneumocystis pneumonia (PcP) among individuals without human immunodeficiency virus (HIV) infection (non-HIV PcP). However, prognostic factors for patients with non-HIV PcP have not been identified. Moreover, A-DROP (for classifying the severity of community-acquired pneumonia) or the blood urea nitrogen-to-serum albumin ratio (BUN/Alb), which is reported to be a predictor of mortality of community-acquired pneumonia, has not been established as an efficient prognostic factor in patients with non-HIV PcP. In this study, we analyzed the prognostic factors for non-HIV PcP and evaluated the prognostic ability of A-DROP and the BUN/Alb ratio.

METHODS

This retrospective study involved a chart review of the medical records of 102 patients diagnosed with non-HIV PcP between January 2003 and May 2019 at five medical facilities.

RESULTS

Overall, 102 patients were involved in this study. The 30-day mortality rate for non-HIV PcP was 20.5% in this study population. Compared with survivors, non-survivors had significantly lower serum albumin levels and significantly higher age, corticosteroid dosage at the PcP onset, alveolar-arterial oxygen gradient, A-DROP score, lactate dehydrogenase levels, blood urea nitrogen levels, and BUN/Alb ratio. Multivariate analysis showed that a high BUN/Alb ratio at treatment initiation was significantly associated with 30-day mortality risk. The receiver operating characteristic curves showed that A-DROP score had the highest prognostic ability in estimating 30-day mortality.

CONCLUSIONS

In patients with non-HIV PcP, a high BUN/Alb ratio is an independent prognostic predictor of mortality risk, and A-DROP is useful for classifying the severity.

Pneumocystis jirovecii Pneumonia in Children with Hematological Malignancies: Diagnosis and Approaches to Management

Pneumocystis jirovecii pneumonia (PJP) is an opportunistic infection that mostly affects children with suppressed cellular immunity. PJP was the most common cause of infectious death in children with acute lymphoblastic leukemia prior to the inclusion of cotrimoxazole prophylaxis as part of the standard medical care in the late 1980s. Children with acute leukemia, lymphomas, and those undergoing hematopoietic stem cell transplantation, especially allogeneic transplantation, are also at high risk of PJP. Persistent lymphopenia, graft versus host disease, poor immune reconstitution, and lengthy use of corticosteroids are significant risk factors for PJP. Active infection may be due to reactivation of latent infection or recent acquisition from environmental exposure. Intense hypoxemia and impaired diffusing capacity of the lungs are hallmarks of PJP, while computerized tomography of the lungs is the diagnostic technique of choice. Immunofluorescence testing with monoclonal antibodies followed by fluorescent microscopy and polymerase chain reaction testing of respiratory specimens have emerged as the best diagnostic methods. Measurement of (1-3)-β-D-glucan in the serum has a high negative predictive value in ruling out PJP. Oral cotrimoxazole is effective for prophylaxis, but in intolerant patients, intravenous and aerosolized pentamidine, dapsone, and atovaquone are effective alternatives. Ιntravenous cotrimoxazole is the treatment of choice, but PJP has a high mortality even with appropriate therapy.

Pneumocystis jirovecii pneumonia in diffuse large B-cell Lymphoma treated with R-CHOP

BACKGROUND

The aim of this study was to estimate the incidence of and risk factors for Pneumocystis pneumonia (PCP) infection in diffuse large B-cell lymphoma (DLBCL) patients treated with rituximab plus cyclophosphamide, doxorubicin, vincristine and prednisone (R-CHOP).

METHODS

The medical records of 739 DLBCL patients who received R-CHOP between May 2004 and January 2019 were retrospectively evaluated. Patients were divided into two groups: those who received primary PCP prophylaxis (prophylaxis group) and those who did not (control group). The incidence rate of PCP in each group was calculated, and risk factors for PCP were evaluated in the control group.

RESULTS

Baseline characteristics were significantly different between the two groups. Compared to the 602 patients who did not receive prophylaxis, the prophylaxis group (n = 137) had poor prognostic factors of older age, high lactate dehydrogenase (LDH) levels, advanced Ann Arbour stage, and high International Prognostic Index (IPI) risk scores. None of the patients receiving PCP prophylaxis developed PCP, while the incidence of PCP in the control group was 8.1% (definite cases 5.5% and probable cases 2.7%). Out of the 49 patients who developed PCP, 10 patients (20.4%) were admitted to the intensive care unit, and the PCP-related death rate was 16.3% (8/49).

CONCLUSION

This study showed that PCP prophylaxis is highly effective against PCP infection and may help guide prevention of PCP during R-CHOP treatment in DLBCL patients.

Long-lasting cluster of nosocomial pneumonia with a single Pneumocystis jirovecii genotype involving different organ allograft recipients

Pneumocystis pneumonia (PCP) outbreaks may occur in solid organ transplant (SOT) patients. Transmissibility of Pneumocystis jirovecii among SOT and non-SOT patients has not been investigated. Ten SOT (ie, 4 heart, 4 kidney, 2 liver allograft recipients) and 11 non-SOT (ie, 7 HIV-infected, 3 hematologic malignancies, and 1 stem cell transplant) patients with PCP were admitted to London Health Sciences Center (LHSC) from October 2014 to August 2016. We investigated the course of illness and outcome of PCP in SOT and non-SOT patients. Post-transplant PCP was frequently an acute-onset disease (90% vs. 18.2%, p = .01) requiring ICU admission (70% vs. 20%, p = .03) and hemodialysis (60% vs. 0, p = .003). Mortality was more frequent in SOT patients (40% vs. 18.1%, p = .36). Multilocus sequence typing (MLST) demonstrated circulation of a single genotype of P. jirovecii among SOT patients. However, 8 different genotypes were detected from non-SOT patients. Reinstitution of prophylaxis successfully controlled post-transplant cluster until end of observation period in October 2019. No transmission was detected from non-SOT patients to SOT recipients. Detection of a single P. jirovecii genotype from all SOT recipients highlights the likelihood of nosocomial transmission. No source control method is recommended by current guidelines. Improvement of preventive strategies is required.

Metagenomic Next-Generation Sequencing in Diagnosis of a Case of Pneumocystis jirovecii Pneumonia in a Kidney Transplant Recipient and Literature Review

Background

Despite the increasing incidences of Pneumocystis jirovecii pneumonia (PCP) in renal transplant recipients, diagnosis of PCP remains challenging due to its nonspecific clinical presentation and the inadequate performance of conventional diagnostic methods. There is a need for novel diagnostic methods.

Case Presentation

A 27-year-old woman developed acute pneumonia 4 months after renal transplantation. Blood tests revealed a low CD4 count, a normal 1,3-beta-D-glucan level and other changes typical of inflammatory responses. Chest imaging showed bilateral diffuse infiltrates. Microscopic examination of stained sputum and bronchoalveolar lavage fluid (BALF) smear specimens did not find Pneumocystis organisms. There was also no evidence for other pathogens known to cause pneumonia in various antibody and culture tests. Direct metagenomic next-generation sequencing (mNGS) analysis of a BALF specimen identified a large number of P. jirovecii reads, allowing to confirm the diagnosis of PCP. Following treatment with trimethoprim-sulfamethoxazole for two weeks, the patient was cured and discharged.

Conclusion

This case report supports the value of mNGS in diagnosing PCP, highlights the inadequate sensitivity of conventional diagnostic methods for PCP, and calls for the need to add PCP prophylaxis to the current Diagnosis and Treatment Guideline of Invasive Fungal Infections in Solid Organ Transplant Recipients in China.

Recent epidemiology of Pneumocystis pneumonia in Japan

OBJECTIVES

The objective of this study was to describe the recent epidemiology of Pneumocystis pneumonia (PCP) in Japan using a nationwide database.

METHODS

We extracted data of inpatients with PCP from the Diagnostic Procedure Combination database, a national inpatient database in Japan, from January 2010 to December 2016.

RESULTS

During the study period, 4293 PCP patients were identified, including 4073 adults and 220 children. In adults, the most common comorbidity was hematologic malignancy (31%), followed by diabetes mellitus (30%), rheumatic/collagen diseases (26%), and solid organ tumors (18%). In children, there were few patients with rheumatic diseases (5%) or diabetes mellitus (2%), but immunodeficiency (without human immunodeficiency virus) was more common (28%). Few biological products were used for adult and pediatric patients; CD20 inhibitors, TNF-α inhibitors, interleukin receptor inhibitors, and CTLA-4 inhibitor were used for 8.6% and 2.4%, 1.3% and 0%, 1.2% and 4.7%, and 0.2% and 0% of adult and pediatric patients, respectively. Based on data stratified by bed count, the annual numbers of PCP patients in Japan were estimated as 2221 adults and 123 pediatric patients. The mortality was higher in adults (27%) than in pediatric patients (21%) (P = 0.041).

CONCLUSIONS

The underlying disease and mortality were apparently different between adult and pediatric PCP patients.

Possible Diagnostic Delays and Missed Prevention Opportunities in Pneumocystis Pneumonia Patients Without HIV: Analysis of Commercial Insurance Claims Data-United States, 2011-2015

Background

Pneumocystis pneumonia (PCP) is a life-threatening but treatable and preventable fungal infection in immunocompromised persons. Previous studies suggest that persons without HIV who develop PCP (PCPHIV-) experience more acute, severe illness than persons with HIV who develop PCP (PCPHIV+). We analyzed health insurance claims data to compare demographics, underlying conditions, symptoms, and prescriptions for PCPHIV+ and PCPHIV-.

Methods

We used the IBM MarketScan Research Databases to identify patients diagnosed with PCP during 2011-2015. We analyzed claims 1 year before to 3 months after diagnosis to compare PCPHIV+ and PCPHIV-.

Results

Among 3938 patients, 70.4% were PCPHIV-. Compared with PCPHIV+, PCPHIV- were more likely to be older (median, 60 vs 45 years; P < .0001), female (51.5% vs 20.2%; P < .0001), hypoxemic (13.5% vs 7.1%; P < .0001), and to die within 90 days (6.6% vs 4.2%; P < .0001). The most common underlying conditions among PCPHIV- included chronic pulmonary diseases (54.6%), solid tumors (35.1%), hematologic malignancies (20.1%), and rheumatologic conditions (14.0%). The median time between the first visit for PCP-related symptoms and PCP diagnosis was longer for PCPHIV- than PCPHIV+ (25 vs 16 days; P < .0001). In the 3 months before PCP diagnosis, PCPHIV- were less likely to have an outpatient prescription for PCP prophylaxis than PCPHIV+ (6.9% vs 10.6%; P = .0001).

Conclusions

PCPHIV- may experience a prolonged illness course and diagnostic delays compared with PCPHIV+. Clinicians should maintain a high index of suspicion for PCP in immunocompromised patients with compatible symptoms, regardless of HIV status.