Pneumocystis jirovecii pneumonia in pediatric patients: an analysis of 15 confirmed consecutive cases during 14 years

Clinical Characteristics and Prognosis of the Modified Probable Pneumocystis jirovecii Pneumonia in Korean Children, 2001-2021

There are few data about Pneumocystis jirovecii pneumonia (PCP) in children, particularly in developed countries. This study investigated the clinical characteristics and prognosis of the clinical PCP in non-HIV-infected Korean children. Children with positive results for the staining and/or polymerase chain reaction (PCR) for P. jirovecii between 2001 and 2021 were identified. Patients were grouped into clinical PCP, which comprised proven and modified probable cases, and non-PCP groups. Modified probable PCP (mp-PCP) indicate the case which P. jirovecii was detected by conventional PCR rather than real-time PCR test. The differences in demographic and clinical characteristics were analyzed between the groups. A total of 110 pneumonia cases with positive results for P. jirovecii PCR and/or stain were identified from 107 children. Of these, 28.2% were classified as non-PCP, 12.7% of proven PCP, and 59.1% of mp-PCP. Compared with the non-PCP group, the mp-PCP group had a significantly higher rate of solid organ transplantation (3.2% vs. 24.6%), fever (58.1% vs. 76.9%), tachypnea (25.8% vs. 66.2%), dyspnea (48.4% vs. 83.1%), desaturation (48.4% vs. 80.0%), and bilateral ground-glass opacity on chest radiograph (19.4% vs. 73.8%). However, when the mp-PCP group was compared with the proven PCP group, there was no statistically significant difference. For children with clinical PCP, age under 5 years of age (odds ratio [OR] 10.7), hospital-onset (OR 6.9), and desaturation as initial symptom (OR 63.5) were significant risk factors for death in multivariable analysis. Modified probable PCP might reliably reflect true PCP in terms of patient's demographic, clinical features, treatment response, and prognosis. Immunocompromised children with hospital-onset pneumonia who are younger than 5 years of age and have desaturation would be more cautiously and aggressively managed for survival through the screening for P. jirovecii by conventional PCR on appropriate lower respiratory specimens.

Modelling the Cost-Effectiveness and Budget Impact of a Newborn Screening Program for Spinal Muscular Atrophy and Severe Combined Immunodeficiency

Spinal muscular atrophy (SMA) and severe combined immunodeficiency (SCID) are rare, inherited genetic disorders with severe mortality and morbidity. The benefits of early diagnosis and initiation of treatment are now increasingly recognized, with the most benefits in patients treated prior to symptom onset. The aim of the economic evaluation was to investigate the costs and outcomes associated with the introduction of universal newborn screening (NBS) for SCID and SMA, by generating measures of cost-effectiveness and budget impact. A stepwise approach to the cost-effectiveness analyses by decision analytical models nested with Markov simulations for SMA and SCID were conducted from the government perspective. Over a 60-year time horizon, screening every newborn in the population and treating diagnosed SCID by early hematopoietic stem cell transplantation and SMA by gene therapy, would result in 95 QALYs gained per 100,000 newborns, and result in cost savings of USD 8.6 million. Sensitivity analysis indicates 97% of simulated results are considered cost-effective against commonly used willingness-to-pay thresholds. The introduction of combined NBS for SCID and SMA is good value for money from the long-term clinical and economic perspectives, representing a cost saving to governments in the long-term, as well as improving and saving lives.

Economic Evaluation of Newborn Screening for Severe Combined Immunodeficiency

Evidence on the cost-effectiveness of newborn screening (NBS) for severe combined immunodeficiency (SCID) in the Australian policy context is lacking. In this study, a pilot population-based screening program in Australia was used to model the cost-effectiveness of NBS for SCID from the government perspective. Markov cohort simulations were nested within a decision analytic model to compare the costs and quality-adjusted life-years (QALYs) over a time horizon of 5 and 60 years for two strategies: (1) NBS for SCID and treat with early hematopoietic stem cell transplantation (HSCT); (2) no NBS for SCID and treat with late HSCT. Incremental costs were compared to incremental QALYs to calculate the incremental cost-effectiveness ratios (ICER). Sensitivity analyses were performed to assess the model uncertainty and identify key parameters impacting on the ICER. In the long-term over 60 years, universal NBS for SCID would gain 10 QALYs at a cost of US $0.3 million, resulting in an ICER of US$33,600/QALY. Probabilistic sensitivity analysis showed that more than half of the simulated ICERs were considered cost-effective against the common willingness-to-pay threshold of A$50,000/QALY (US$35,000/QALY). In the Australian context, screening for SCID should be introduced into the current NBS program from both clinical and economic perspectives.

Clinical-epidemiological characteristics of Pneumocystis jirovecii pneumonia in a tertiary hospital in Spain

INTRODUCTION

HIV infection was the main risk of suffering Pneumocystis jirovecii pneumonia (PJP). The clinical-epidemiological characteristics of PJP have currently changed, with there being few studies on this.

METHODS

A retrospective observational study was carried out on paediatric patients diagnosed with PJP over a 17 year period in a third level hospital in Spain.

RESULTS

A total of 23 patients were included, of whom 7/23 (47.8%) suffered a haematological disease, 5/23 (21.7%) a primary immunodeficiency, and 4/23 (17.4%) an HIV infection. Prophylaxis with trimethoprim-sulfamethoxazole (TMP-SMX) was received by 11/23 (47.8%) patients. All were treated with TMP-SMX and 18/23 (78.3%) with systemic glucocorticoids. There were six (26.1%) deaths, of which one of them (16.7%) suffered an HIV infection. A higher mortality was seen in the non-HIV patients with greater leucocytosis, greater CO2 retention, and a higher heart rate at onset, differences not observed in HIV patients. No differences were found in mortality in relation to the predisposing factor, use of pTMP-SMX, or treatment with glucocorticoids.

CONCLUSIONS

Paediatric patients with haematological cancers are currently the main risk group of developing PJP in this age group. No differences were found in mortality between patients with or without HIV infection as predisposing factor. The mortality among non-HIV patients was higher in those that had greater leucocytosis, greater CO2 retention, and increased heart rate at onset. A better prognosis was not seen in patients that received prophylaxis with TMP-SMX prior to the development of the PJP, or in those that received glucocorticoids as part of the treatment.

Twice weekly prophylaxis with trimethoprim/sulfamethoxazole for Pneumocystis jirovecii pneumonia in pediatric oncology patients

Current recommendations for prophylaxis of Pneumocystis jirovecii pneumonia in oncology patients include administration of trimethoprim/sulfamethoxazole (TMP/SMX) three times weekly or the same total weekly dose given daily. The primary objective of this study was to evaluate the efficacy of two consecutive days per week of TMP/SMX for prevention of Pneumocystis jirovecii pneumonia (PJP) in pediatric oncology patients. A retrospective cohort, single-center analysis was conducted in oncology patients 21 years and younger who received TMP/SMX for PJP prophylaxis between February 1, 2013 and July 31, 2017. Changes to the prophylaxis regimen were documented and analyzed. A total of 322 patients received TMP/SMX on two consecutive days per week for PJP prevention, of whom four had confirmed PJP (1.3%). Neutropenia was the most common reason for switching to alternative prophylaxis therapy (11.5%). Two consecutive prophylaxis days with TMP/SMX may be insufficient to prevent PJP in children with hematologic malignancies. Neutropenia remains a barrier for TMP/SMX use for PJP prophylaxis. Further studies to compare PJP incidence in children receiving alternative prophylaxis regimens should be considered.

Pneumocystis jirovecii pneumonia in children. A retrospective study in a single center over three decades

INTRODUCTION

Pneumocystis jirovecii pneumonia (PJP) is a life-threatening condition in immunocompromised children. Our aim is to analyze the epidemiologic and clinical characteristics of PJP cases in our setting, describing the prognosis and related risk factors.

METHODS

Retrospective study including all pediatric patients (≤18 years) with PJP admitted to our hospital (January 1989-December 2016). Case definition: patient with acute pneumonitis and P.jirovecii detection in bronchoalveolar lavage or tracheal aspirate using methenamine silver or direct antibody fluorescence staining, or Real-Time Polymerase Chain Reaction.

RESULTS

Twenty-five cases (0.9 cases/year) were identified. Median age was 2.2 years (interquartile range: 0.5-12.3), 64% were male, and 12% were receiving appropriate antimicrobial prophylaxis. Cytomegalovirus coinfection was detected in 26% cases. The most common underlying diseases were primary immunodeficiencies (36%) and 16% were human immunodeficiency virus (HIV)-infected children. Eighteen were admitted to the pediatric intensive care unit (PICU) and overall 30-day mortality was 20% (31.25% in HIV non-infected vs 0% in HIV-infected patients; OR: 0.33, 95% CI: 0.02-7.24, p=0.55). Clinical outcome was worse in girls and those patients requiring adjuvant steroid therapy. HIV non-infected patients, higher initial LDH, younger age and shorter time elapsed between diagnosis of PJP and the underlying disease were identified as risk factors to be admitted to the PICU (p=0.05, p=0.026, p=0.04 and p=0.001 respectively).

CONCLUSION

Accompanying the widespread use of combined antiretroviral therapy, PJP has been diagnosed almost exclusively in HIV non-infected children at our institution. Moreover, significant higher morbidity rates associated with PJP are seen in this group of patients.

Pneumocystis jiroveci pneumonia in Taiwan from 2014 to 2017: Clinical manifestations and outcomes between pediatric and adult patients

BACKGROUND

Pneumocystis jiroveci pneumonia (PJP) is a severe and lethal opportunistic infection in the immunocompromised patients. As the increasing usage of immunosuppressants, the incidence of non-HIV related PJP has increased in recent years. Still, there is little research regarding children with PJP. The aim of this study is to understand PJP more among pediatric population.

METHODS

We reviewed the medical records of the patients with PJP in National Taiwan University Hospital from 2014 to 2017. Diagnosis was made if the patient met all of the criteria: presence of relevant pulmonary symptoms and signs, pulmonary infiltrates on images, detection of Pneumocystis jiroveci from respiratory specimens via polymerase chain reaction (PCR), and received antibiotics for PJP.

RESULTS

Twenty children and 132 adults were enrolled in this study. The most common underlying diseases among children included malignancy (40%), post-transplantation (30%), and primary immunodeficiency (20%). The major underlying diseases in adults included malignancy (36%), HIV with acquired immunodeficiency syndrome (AIDS) (31%), and autoimmune diseases (24%). There is no significant difference in the clinical manifestations, mortality, and complication between children and adults, but children tended to have less chance of using alternative antibiotics, methylprednisolone and inhaled nitric oxide (NO). The chance of concomitant cytomegalovirus disease was also significantly lower in pediatric patients.

CONCLUSION

No significant difference was found in the clinical manifestations, mortality, and complication between children and adults, but children tended to have lesser chance of using alternative antibiotics, methylprednisolone and inhaled NO. The chance of associated cytomegalovirus (CMV) disease was also significantly lower in children.