Incidence, etiology, and outcome of hospital-acquired pneumonia in patients with acute exacerbation of fibrotic idiopathic interstitial pneumonia

BACKGROUND

Acute exacerbations (AEs) of fibrotic idiopathic interstitial pneumonia (fIIP) that require hospitalization occur in some patients. During hospitalization, these patients can develop hospital-acquired pneumonia (HAP), a common hospital-acquired infection with a high mortality rate. However, the characteristics of HAP in AE-fIIP remain unknown. The purpose of this study was to determine the incidence, causative pathogens, and outcomes of HAP in patients with AE-fIIP.

METHODS

The medical records of consecutive patients who were hospitalized with AE-fIIP from January 2008 to December 2019 were analyzed for the incidence, causative pathogen, and survival of HAP. The records of patients with an obvious infection-triggered AE were excluded from analysis.

RESULTS

There were 128 patients with AE-fIIP (89 with idiopathic pulmonary fibrosis [IPF] and 39 with non-IPF fIIP) who were hospitalized a total of 155 times (111 with IPF and 44 with non-IPF fIIP). HAP occurred in 49 patients (40 with IPF and 9 with non-IPF fIIP). The incidence and the in-hospital mortality rates of HAP in patients with AE-fIIP were high, at 32.2% and 48.9%, respectively. Corynebacterium spp. was the most common causative pathogen, which was followed by human cytomegalovirus (HCMV).

CONCLUSIONS

The incidence and the in-hospital mortality rates of HAP in patients with AE-fIIP are high. To improve their survival, patients with fIIP who had AEs and HAP should receive prompt empirical treatment for possible infections with Corynebacterium spp. and testing for HCMV.

Survival and acute exacerbation for patients with idiopathic pulmonary fibrosis (IPF) or non-IPF idiopathic interstitial pneumonias: 5-year follow-up analysis of a prospective multi-institutional patient registry

OBJECTIVE

Few prospective cohort studies with relatively large numbers of patients with non-idiopathic pulmonary fibrosis (non-IPF) of idiopathic interstitial pneumonia (IIP) have been described. We aimed to assess disease progression and cause of death for patients with non-IPF IIPs or IPF under real-life conditions.

METHODS

Data were analysed for a prospective multi-institutional cohort of 528 IIP patients enrolled in Japan between September 2013 and April 2016. Diagnosis of IPF versus non-IPF IIPs was based on central multidisciplinary discussion, and follow-up surveillance was performed for up to 5 years after patient registration. Survival and acute exacerbation (AE) were assessed.

RESULTS

IPF was the most common diagnosis (58.0%), followed by unclassifiable IIPs (35.8%) and others (6.2%). The 5-year survival rate for non-IPF IIP and IPF groups was 72.8% and 53.7%, respectively, with chronic respiratory failure being the primary cause of death in both groups. AE was the second most common cause of death for both non-IPF IIP (24.1%) and IPF (23.5%) patients. The cumulative incidence of AE did not differ significantly between the two groups (p=0.36), with a 1-year incidence rate of 7.4% and 9.0% in non-IPF IIP and IPF patients, respectively. We found that 30.2% and 39.4% of non-IPF IIP and IPF patients, respectively, who experienced AE died within 3 months after an AE event, whereas 55.8% and 66.7% of such patients, respectively, died within 5 years after registration.

CONCLUSION

Closer monitoring of disease progression and palliative care interventions after AE are important for non-IPF IIP patients as well as for IPF patients.

[CLINICAL EFFICACY OF SUSTAINED HIGH-EFFICACY DAILY DIAFILTRATION USING A MEDIATOR-ADSORBING MEMBRANE AND DIRECT HEMOPERFUSION WITH A POLYMYXIN B-IMMOBILIZED FIBER COLUMN IN TREATING ACUTE EXACERBATION OF IDIOPATHIC INTERSTITIAL PNEUMONIAS]

OBJECTIVES

The aim of this study is to investigate the clinical outcomes of patients with steroid-resistant acute exacerbation of idiopathic interstitial pneumonias treated with blood purification therapy comprising direct hemoperfusion using a polymyxin B-immobilized fiber column (PMX-DHP) and sustained high-efficacy daily diafiltration using a mediator-adsorbing membrane (SHEDD-fA).

METHODS

The clinical outcomes and respiratory function were retrospectively compared between 6 patients who underwent blood purification therapy (blood purification group) and 15 patients (control group) who blood purification therapy.

RESULTS

The patients in the blood purification group showed a higher PaO2/FiO2 ratio than those in the control group. Twenty-eight days (83%; 5/6 vs. 20%; 3/15) and ninety days (67%; 4/6 vs. 6.7%; 1/15) survival rates were also higher in the blood purification group. The blood purification group also showed a better 90-day survival curve (Hazard ratio=0.260) compared to the control group.

CONCLUSIONS

In conclusion, combination blood purification therapy comprising PMX-DHP and SHEDD-fA may be used to treat acute exacerbation of idiopathic interstitial pneumonias.

[Idiopathic interstitial pneumonias]

Idiopathic interstitial pneumonias represent approximately 30% of all interstitial lung diseases. The new classification of idiopathic interstitial pneumonias published in 2013 distinguishes 6 major entities, including chronic fibrosing forms (idiopathic pulmonary fibrosis and nonspecific interstitial pneumonia), acute/subacute forms (cryptogenic organizing pneumonia and acute interstitial pneumonia) and smoking-related disorders (respiratory bronchiolitis interstitial lung disease and desquamative interstitial pneumonia). Pleuroparenchymal fibroelastosis is individualized as a new rare clinco-pathologic entity. For cases not fitting any specific clinic- pathological category, a pragmatic classification based on disease behavior is proposed.

Prognostic factors in interstitial lung disease associated with primary Sjögren's syndrome: a retrospective analysis of 33 pathologically-proven cases

INTRODUCTION

Interstitial lung disease associated with primary Sjögren's syndrome (pSS-ILD) shows several patterns such as nonspecific interstitial pneumonia (NSIP) and usual interstitial pneumonia (UIP). Although UIP is a well-recognized prognostic determinant in idiopathic interstitial pneumonias, whether this is also the case in pSS-ILD is unclear. The objectives of this study were to evaluate the prognostic effect of UIP, and to identify the prognostic factors in pSS-ILD.

METHODS

A retrospective review of medical records identified 33 consecutive patients with pathologically-proven pSS-ILD. Each patient was classified into each ILD pattern by multidisciplinary analysis. Baseline clinical-radiologic-pathologic characteristics and survival rates were compared between the ILD patterns. Finally, the prognostic factors in pSS-ILD were assessed by univariate and subsequent multivariate analyses using Cox's proportional hazards regression model.

RESULTS

pSS-ILD patients were diagnosed with NSIP (n = 22) or UIP (n = 11). The median follow-up period was 110 months, and five-year survival rate was 87.3% in the total patient population. The prognosis of the UIP patients was not significantly different from that of the NSIP patients (NSIP to UIP, hazard ratio [HR]: 0.77, 95% confidence interval [CI]: 0.18-3.36, P = 0.73). Multivariate analysis identified PaCO2 (HR: 1.68 per 1 Torr increase, 95% CI: 1.24-2.28, P < 0.01), extent of reticular abnormality on high-resolution CT (HR: 4.17 per 1-grade increment, 95% CI: 1.18-14.73, P = 0.03), and severity of fibroblastic foci (HR: 9.26 per 1-grade increment, 95% CI: 1.74-49.35, P < 0.01) as prognostic factors in pSS-ILD.

CONCLUSIONS

UIP in pSS-ILD was not related to poorer prognosis than NSIP. Assessment of detailed clinical-radiologic-pathologic findings is more important than distinguishing UIP to evaluate prognosis in this disease.

Invasive mechanical ventilation in patients with fibrosing interstitial pneumonia

OBJECTIVE

The prognosis of patients with idiopathic pulmonary fibrosis or fibrosing idiopathic nonspecific interstitial pneumonia undergoing invasive mechanical ventilation (MV) for acute respiratory failure is known to be poor. The issue of life support in these patients needs to be reconsidered in light of changes during the past decade in ventilator settings and in the management of acute exacerbation. We therefore aimed to reassess the prognosis of such patients.

METHODS

We retrospectively assessed the outcomes of all medical patients with idiopathic pulmonary fibrosis or fibrosing idiopathic nonspecific interstitial pneumonia who required invasive MV in 3 university hospitals in the Paris area from January 2002 to April 2009.

RESULTS

In total, 27 patients (mean age, 66 ± 12.8 years) required invasive MV in the intensive care unit: 8 (30%) were successfully weaned from MV, and 6 and 4 were discharged from the intensive care unit and the hospital, respectively. Survivals for patients who did not undergo lung transplant were 22%, 3.7%, and 3.7%, at 30 days, 6 months, and 12 months, respectively.

CONCLUSIONS

We confirm that use of invasive MV for acute respiratory failure in patients with idiopathic pulmonary fibrosis or fibrosing idiopathic nonspecific interstitial pneumonia is associated with a high mortality; however, a subset of patients may be discharged alive from the intensive care unit and hospital, providing an opportunity to consider lung transplant in case of eligibility. Our results suggest that invasive MV should not be systematically denied to these patients but discussed on a case-by-case basis.

Polymyxin B-immobilized fiber column (PMX) treatment for idiopathic pulmonary fibrosis with acute exacerbation: a multicenter retrospective analysis

OBJECTIVE

The prognosis of idiopathic pulmonary fibrosis (IPF) patients with acute exacerbation (AE) is reported to be extremely poor. Several clinical studies suggest that direct hemoperfusion with polymyxin B-immobilized fiber (PMX) may have beneficial effects on AE in patients with interstitial pneumonia (IP). The aim of this multicenter retrospective analysis was to investigate whether PMX treatment could provide improvement of oxygenation and survival benefits in IPF patients with AE.

METHODS

We conducted a retrospective study of 160 IP patients (including 73 IPF) with AE treated by PMX at 18 institutions in Japan. PMX treatment was carried out twice. The total hemoperfusion time of PMX treatment was, on average, 12 hours. Data concerning oxygenation on PMX treatment and survival after AE were collected and analyzed.

RESULTS

In IPF patients with AE, arterial oxygen tension (PaO(2))/inspiratory oxygen fraction (FiO(2)), (P/F) ratio was significantly improved at the end of the 2nd treatment with PMX (173.9 ± 105.4 to 195.2 ± 106.8 Torr, p=0.003). White blood cell count was significantly reduced at the end of the 2nd treatment (13,330 ± 7,002 to 9,426 ± 5,188 /mm(3), p<0.001). These clinical changes were also observed on analysis of all 160 IP patients with AE. The one- and three-month survival rates of IPF patients after AE were 70.1% and 34.4%, respectively.

CONCLUSION

PMX treatment may improve oxygenation and survival in IPF patients with AE. Prospective, controlled trials of PMX treatment for IPF with AE are warranted to verify this potential benefit.

[Successful treatment with intensive immunosuppressive therapy and mechanical ventilation for idiopathic pneumonia syndrome following allogeneic bone marrow transplantation]

A 45-year-old man with acute myelogenous leukemia (WHO classification, AML with multilineage dysplasia) received allogeneic bone marrow transplantation from an HLA-identical brother in first remission. He became febrile on day 7, and pulmonary failure and multi-organ failure developed subsequently, requiring mechanical ventilation. Chest X-ray and CT scan demonstrated diffuse interstitial shadows, suggesting the development of idiopathic pneumonia syndrome. Administration of methylprednisolone and tacrolimus was effective, but respiratory failure exacerbated along with a decrease in the dose of steroids. Lung biopsy revealed organizing pneumonia with CMV pneumonia. Methylprednisolone and mycophenolate mofetil were instituted, which led to an improvement of lung injury. Intensive immunosuppressive therapy with mechanical ventilation should be considered for the treatment of idiopathic pneumonia syndrome after allogeneic bone marrow transplantation.

Idiopathic interstitial pneumonias: progress in classification, diagnosis, pathogenesis and management

The idiopathic interstitial pneumonias are a heterogeneous group of poorly understood diseases with often devastating consequences for those afflicted. Subclassification of the idiopathic interstitial pneumonia based on clinical-radiological-pathological criteria has highlighted important pathogenic, therapeutic and prognostic implications. The most critical distinction is the presence of usual interstitial pneumonia, the histopathological pattern seen in idiopathic pulmonary fibrosis. Idiopathic pulmonary fibrosis has a worse response to therapy and prognosis. New insight into the pathophysiology of usual interstitial pneumonia suggests a distinctly fibroproliferative process, and antifibrotic therapies show promise. While the clinical and radiographic diagnosis of idiopathic interstitial pneumonias can be made confidently in some cases, many patients require surgical lung biopsy to determine their underlying histopathology. A structured, clinical-radiological-pathological approach to the diagnosis of the idiopathic interstitial pneumonias, with particular attention to the identification of idiopathic pulmonary fibrosis, insures proper therapy, enhances prognostication, and allows for further investigation of therapies aimed at distinct pathophysiology.