A retrospective clinical research of relapsed organizing pneumonia

Forensic application of three interstitial pneumonia markers: search for new pneumonia markers in dead bodies

In forensic cases, detailed identification of pneumonia is important. Our objective was to statistically determine the applicability of three interstitial lung disease (ILD) markers for forensic diagnosis using serum collected from dead bodies with various postmortem intervals (PMIs). We retrospectively analyzed the levels of postmortem serum Krebs von den Lungen-6 (KL-6) and pulmonary surfactant-associated proteins A and D (SP-A and SP-D) using 221 samples obtained during forensic autopsy at our facility from 2019 to 2023. We evaluated the diagnostic efficacy of ILD markers for various pneumonias against the pathological diagnosis, and examined the assessment of the severity of ILD. When comparing the ILD group with bacterial pneumonia (BP) versus the control group, there was a significant increase in KL-6 in the ILD group. When comparing the severe ILD (SILD) group with the mild ILD (MILD) group, there was a significant increase in KL-6 and SP-D in the SILD group. The optimal cutoff values for differentiating SILD were 607.0 U/mL for KL-6, 55.5 ng/mL for SP-A, and 160.0 ng/mL for SP-D, and the sensitivity/specificity (%) of KL-6, SP-A, and SP-D for SILD were 84.1/95.2, 55.6/85.7, and 66.7/74.6, respectively. This is the first study to examine KL-6 in postmortem serum in forensic medicine. By analyzing dead bodies with various PMIs, our results confirmed statistically that postmortem serum KL-6 specifically detects ILD, postmortem serum SP-A has high sensitivity to lung injury, and postmortem serum SP-D is potentially useful in assessing the severity of ILD.

Clinical Characteristics and Predictors of the Recurrence of Organizing Pneumonia Associated With Rheumatoid Arthritis

OBJECTIVE

To clarify the clinical characteristics of organizing pneumonia (OP) in rheumatoid arthritis (RA; RA-OP) and the association of OP development with RA exacerbation, and to identify OP recurrence predictors.

METHODS

Data from 33 patients with RA-OP admitted to our hospital were retrospectively analyzed (2006-2016).

RESULTS

RA onset preceded OP onset in 82% of patients, whereas OP onset preceded (OP-preceding) or co-occurred with RA in 9% of patients each. Median age at first OP onset was 64.0 years, and the period from RA onset to first OP onset was 5.5 years. At OP onset, 42% of events exhibited unilateral involvement and 76% had normal Krebs von den Lungen-6. RA disease control remained optimal in 52% of events and was exacerbated in 18% of events. Ten patients (30%) experienced OP recurrence with an interval of 13.0 months between events, and the first OP recurrence rate was 127/1000 person-years. Compared with nonrecurrent cases (n = 14), recurrent cases (n = 10) showed lower age at first OP onset (59.5 vs 67.1 yrs; P = 0.04) and a shorter period from RA onset to first OP onset (6.4 vs 14.2 yrs; P = 0.047); moreover, these cases included a higher number of OP-preceding patients (30% vs 0%; P = 0.03) and ever smokers (80% vs 36%; P = 0.03). OP-preceding patients showed shorter median recurrence-free survival time (15 vs 136 months; P = 0.01) and higher recurrence risk (hazard ratio 5.45; P = 0.02).

CONCLUSION

RA-OP showed a high recurrence rate and was not associated with RA exacerbation. Four RA-OP recurrence predictors were identified.

Minimal effective dose of maintenance steroid therapy for relapse of cryptogenic organizing pneumonia

BACKGROUND

Long-term maintenance steroid therapy (MST) is frequently required for repeated relapses of cryptogenic organizing pneumonia (COP); however, the optimal minimal dose has not been clarified. Therefore, this study evaluated the minimal MST dose required to prevent repeated relapses and identify relapse predictors.

METHODS

We retrospectively reviewed the medical records of patients with steroid-treated COP and compared background factors between the non-relapse and relapse groups. We also reviewed the treatment course in the relapse group and determined the minimal effective steroid dose based on the MST dose at relapse events and the current relapse prevention dose.

RESULTS

In total, 48 patients were identified, including 27 (56%) in the non-relapse group and 21 (44%) in the relapse group. Receiver operating characteristic curve analysis identified prednisolone at 5 mg/day as the optimal cut-off value in the relapse group. Relapse-free time in patients with relapsed COP was significantly longer in the MST dose ≥5 mg/day group than in the <5 mg/day group (log-rank P = 0.003; hazard ratio, 0.19; 95% confidence interval [CI], 0.04-0.60). Multivariate logistic regression analysis demonstrated that a high eosinophil percentage and CD4/CD8 ratio in bronchoalveolar lavage fluid (BALF) were predictors of relapse (odds ratio [OR], 1.12; 95% CI, 1.02-1.23; P = 0.008 and OR, 3.87; 95% CI, 1.29-11.6; P = 0.008, respectively).

CONCLUSIONS

Our results indicate that 5 mg/day of prednisolone may be the minimal effective dose for preventing repeated relapses, and a high BALF eosinophil percentage and CD4/CD8 ratio are independent predictors of relapse.

Clinical features of relapsed connective tissue disease-associated organizing pneumonia

BACKGROUND

Organizing pneumonia (OP) is recognized as a nonspecific lung injury response characterized histopathologically by the presence of intra-alveolar buds of granulation tissue. Most OP patients show excellent responses to corticosteroids, but relapse is frequently seen when corticosteroids are tapered or discontinued. Although several factors associated with relapse have been reported in cryptogenic OP (COP), the clinical features and risk factors associated with relapse in connective tissue disease-associated OP (CTD-OP) have yet to be fully understood.

METHODS

We retrospectively reviewed data on 47 CTD-OP patients. We investigated the frequency of relapse and compared the clinical data between CTD-OP with and without relapse to clarify the risk factors for relapse.

RESULTS

Eleven (23.4%) CTD-OP patients had relapses of OP during the study. In the multivariate analysis, no CTD treatment at OP diagnosis [O.R. 11.920, p = 0.012] and partial remission after steroid treatment [O.R. 35.944, p = 0.045] were independent risk factors for relapse. Among rheumatoid arthritis-associated OP (RA-OP) patients, partial remission after steroid treatment [O.R. 16.151, p = 0.047] and age at OP diagnosis [O.R. 0.899, p = 0.045] were independent risk factors for relapse. Most of the relapsed OP patients who were on no medication at OP diagnosis later developed CTD.

CONCLUSION

CTD-OP patients with residual disease on HRCT after treatment and who had OP diagnosis preceding CTD diagnosis were more likely to have an OP relapse. During the clinical course of relapsed OP patients, it is necessary to pay attention to the onset of CTD.

Extracorporeal Membrane Oxygenation for Secondary Organizing Pneumonia after Severe SARS-CoV-2 Infection: A Case Report

(Background) COVID-19 is caused by SARS-CoV-2 infection and may result in unfavorable outcomes. A recent large-scale study showed that treatment with dexamethasone leads to favorable outcomes in patients with severe COVID-19, and the use of extracorporeal membrane oxygenation (ECMO) has also been shown to improve outcomes. Recently, secondary organizing pneumonia (SOP) has been reported after SARS-CoV-2 infection, but the diagnostic and treatment strategies are still unclear. (Case presentation) Here, we report a patient with severe COVID-19 who developed SOP even after the use of dexamethasone, for whom the introduction of ECMO on the 19th day after hospitalization led to a favorable outcome. (Conclusions) Life-threatening SOP may evolve even after the use of dexamethasone, and the late-phase introduction of ECMO may save such patients with COVID-19.

Rapidly progressive organizing pneumonia associated with COVID-19

We report a case of clinically diagnosed secondary organizing pneumonia (SOP) associated with coronavirus disease 2019 (COVID-19). A 70-year-old woman who had been diagnosed with COVID-19 was admitted to Hokkaido University Hospital. Although her fever, cough, dyspnea, and serum C-reactive protein levels improved, she developed rapidly progressive respiratory failure and computed tomography revealed the development of bilateral lung consolidation. Her dyspnea was relieved, and her oxygenation levels and radiological findings improved after commencing corticosteroid treatment. Blood biomarkers for interstitial lung disease, Krebs von den Lungen-6 (KL-6) and surfactant protein D (SP-D), showed different responses during the clinical course of her disease. Evaluation of serial changes in levels of KL-6 and SP-D may help diagnose and monitor COVID-19-associated organizing pneumonia (OP). Clinicians should be aware that SOP can develop in response to COVID-19 and that these patients may benefit from the use of steroids.

Seroradiologic prognostic evaluation of acute exacerbation in patients with idiopathic interstitial pneumonia: a retrospective observational study

Background

We previously reported that high-resolution computed tomography (HRCT) patterns and certain serum marker levels can predict survival in patients with acute exacerbation (AE) of idiopathic pulmonary fibrosis (IPF) and in those with idiopathic interstitial pneumonias (IIPs). The utility of serum marker changes before and during AE has not been previously evaluated. This study aimed to clarify whether changes in serum marker levels could improve the prognostic significance of HRCT patterns in patients with AE-IIPs.

Methods

Seventy-seven patients (60 males, 17 females) with AE-IIP diagnosed between 2004 and 2016 and whose serum Krebs von den Lungen (KL)-6 and surfactant protein (SP)-D levels were measured before and at the onset of AE were enrolled in this study. The HRCT pattern of each patient was classified as diffuse, multifocal, or peripheral. We examined the prognostic significance of the HRCT pattern, increased serum marker levels, and a combination of these parameters using Cox proportional hazard regression analysis.

Results

Fifty-three patients had IPF and 24 had non-IPF IIP. A serum KL-6 level that was increased compared with the level in the stable state (ΔKL-6/ST-KL-6: ≤0.211) was a significantly poor prognostic factor in patients with a multifocal pattern. Multivariate Cox analysis identified long-term oxygen therapy, a partial oxygen tension/fraction of inspired oxygen ratio ≤200 Torr, and an elevated SP-D level during a stable state to be significantly poor prognostic factors in all patients. A diffuse HRCT pattern was not a significant prognostic factor in an AE-IIP in multivariate analysis after adjustment; however, a multifocal pattern accompanying a ΔKL-6/ST-KL-6 ≤0.211 or a diffuse pattern was a significantly poor prognostic factor than a peripheral pattern or a multifocal pattern with ΔKL-6/ST-KL-6 >0.211.

Conclusions

Combining the HRCT pattern and the ΔKL-6/ST-KL-6 value can improve our ability to predict the survival of AE-IIP patients.