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Updated: Aug 31, 2025
Imaging Features of Systemic Sclerosis-Associated Interstitial Lung Disease
Published on: June 16, 2020
Characteristics and Prognosis of Microscopic Polyangiitis Patients with Diffuse Alveolar Hemorrhage and Interstitial
Yu Gu1, Ting Zhang1, Min Peng1
1Department of Respiratory and Critical Care Medicine, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences ＆ Peking Union Medical College, Beijing 100037, China.
Abstract:
Objective To evaluate the clinical characteristics and prognostic predictors of patients with diffuse alveolar hemorrhage (DAH) and/or interstitial lung disease (ILD) secondary to microscopic polyangiitis (MPA) in a Chinese general hospital. Methods We retrospectively reviewed the medical records of MPA patients admitted to internal medicine departments between the year 2002 and 2012. The patients were divided into the ILD, DAH, DAH combined with ILD (DAHILD), and no pulmonary involvement (NPI) groups according to pulmonary involvement patterns. The clinical characteristics at diagnosis were analyzed. The risk factors associated with short-term death and long-term death were identified with Logistic regression and Cox analysis.Results Of 193 newly diagnosed MPA patients, 181 patients were enrolled in the research, of which 19 had DAH alone, 96 had ILD alone, 18 had DAH and DAH concurrently, and 48 had NPI. The median of serum creatine level in the DAH group was 449 μmol/L, significantly higher than that in the ILD group (123 μmol/L, Nemenyi = -35.215, P = 0.045) and DAHILD group (359 μmol/L, Nemenyi = -43.609, P = 0.007). The median follow-up time was 67 (range: 1-199) months. Patients in the ILD group were older than those in the DAH group (median: 69 years vs. 57 years, Nemenyi = 43.853, P= 0.005). The patients with both DAH and ILD had combined features of the two subtypes, and the highest mortality (72.2% at the end of follow-up). The elevated white blood cell count was a risk factor for short-term death (OR = 1.103, 95%CI: 1.008-1.207, P = 0.032 for one month; OR = 1.103, 95%CI: 1.026-1.186, P = 0.008 for one year). Old age (HR= 1.044, 95%CI: 1.023-1.066, P < 0.001), cardiovascular system involvement (HR = 2.093, 95%CI: 1.195-3.665, P = 0.010), poor renal function (HR = 1.001, 95%CI: 1.000-1.002, P = 0.032) were risk factors for long-term death. Pulmonary infections (38/54) were the leading causes of death, especially for the patients with ILD. Besides, 49 patients suffered from pulmonary infections in the first year after diagnosis. Conclusions MPA patients who presented with different pulmonary involvement patterns have completely different clinical features. These subtypes probably have different pathogenesis and should be studied separately.
Insights
Microscopic polyangiitis (MPA) patients with diffuse alveolar hemorrhage (DAH) and interstitial lung disease (ILD) show distinct clinical features and prognoses. DAHILD patients face the highest mortality, highlighting the need for subtype-specific research.
Area of Science:
- Pulmonary Medicine
- Rheumatology
- Clinical Research
Background:
- Microscopic polyangiitis (MPA) can manifest with diverse pulmonary involvements, including diffuse alveolar hemorrhage (DAH) and interstitial lung disease (ILD).
- Understanding the distinct clinical characteristics and prognostic factors of these MPA-related pulmonary subtypes is crucial for patient management.
Purpose of the Study:
- To evaluate the clinical features and identify prognostic predictors for MPA patients with DAH and/or ILD.
- To differentiate between DAH, ILD, and combined DAH and ILD (DAHILD) pulmonary involvement patterns in MPA.
Main Methods:
- Retrospective review of medical records of 181 newly diagnosed MPA patients (2002-2012).
- Classification into ILD, DAH, DAHILD, and no pulmonary involvement (NPI) groups.
- Analysis of clinical characteristics and identification of short-term and long-term death risk factors using logistic regression and Cox analysis.
Main Results:
- The DAH group exhibited significantly higher serum creatinine levels than ILD and DAHILD groups.
- Patients in the ILD group were older than those in the DAH group.
- The DAHILD group had the highest mortality (72.2%).
- Elevated white blood cell count predicted short-term death.
- Old age, cardiovascular involvement, and poor renal function predicted long-term death.
- Pulmonary infections were the leading cause of death, particularly in ILD patients.
Conclusions:
- MPA patients with different pulmonary involvement patterns (DAH, ILD, DAHILD) exhibit distinct clinical features and prognoses.
- These subtypes may arise from different pathogenetic mechanisms, necessitating separate investigation.
- Identifying specific risk factors for mortality in each subtype is essential for targeted interventions.
