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Rapid decrease in forced vital capacity in patients with idiopathic pulmonary upper lobe fibrosis
Kentaro Watanabe1, Nobuhiko Nagata, Yasuhiko Kitasato
1Department of Respiratory Medicine, Fukuoka University School of Medicine, Fukuoka 814-0180, Japan. watanabe@fukuoka-u.ac.jp
Respiratory Investigation
|October 2, 2012
Summary
Idiopathic pulmonary upper lobe fibrosis (IPUF) is a distinct interstitial pneumonia. This condition leads to rapid decline in lung function and has a poor prognosis.
Area of Science:
- Pulmonology
- Pathology
- Radiology
Background:
- Idiopathic pulmonary upper lobe fibrosis (IPUF) is an unclassifiable interstitial pneumonia of unknown etiology.
- IPUF does not fit into existing categories of idiopathic interstitial pneumonias (IIPs).
Purpose of the Study:
- To investigate the clinical, functional, and pathological characteristics of IPUF.
- To differentiate IPUF from other interstitial lung diseases.
Main Methods:
- Evaluation of clinical and histological data from 9 patients with confirmed IPUF.
- Measurement of baseline respiratory function, including forced vital capacity (FVC) monitoring over at least one year in 7 patients.
Main Results:
- Patients were typically slender (BMI 16.0-19.8 kg/m²), with 7 reporting a history of pneumothorax.
- Histological findings included intraalveolar collagen deposition and densely packed elastic fibers in subpleural areas.
- A rapid, near-linear decline in FVC was observed, with a median yearly decline of -20.3%, exceeding that of other chronic fibrosing interstitial pneumonias.
Conclusions:
- IPUF is a unique form of pulmonary fibrosis.
- The condition is characterized by rapid deterioration of ventilatory function.
- IPUF has a poor prognosis.
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