Clinical and CT characteristics of Chinese medicine-induced acute respiratory distress syndrome

Abstract

Objective: The aim of the present study was to explore the clinical and radiographic characteristics of Chinese medicine-induced acute respiratory distress syndrome (ARDS), focusing on high resolution CT (HRCT) findings.

Methodology: Five patients diagnosed with Chinese medicine-induced ARDS were enrolled in the study. Details regarding clinical history, previous medical history, and laboratory data were collected and reviewed. The extent of involvement of each HRCT abnormality was assessed for each of three zones of each lung and was estimated to the nearest 10% of parenchymal involvement.

Results: The causative Chinese medicines were as follows: Sho-saiko-to (two cases), Sai-rei-to (two cases) and Otsu-ji-to (one case). Scutellariae radix was the common ingredient in these drugs. The mean duration of medication use before the onset of ARDS was 22 days (range 7-49 days). High levels of C-reactive protein and lactate dehydrogenase (LDH), and mild liver dysfunction were common laboratory findings. The major HRCT findings were as follows: ground-glass opacity 50.2% (range 37-68%); airspace consolidation 16.0% (7-27%); spared area 26.6% (7-45%). In addition, the abnormalities tended to predominate in the peribronchovascular regions. Furthermore, architectural distortion was seen in all five cases, interlobular septal thickening occurred in four, irregular interface in four, and interlobar effusion in two. Corticosteroid therapy was very effective, and partial pressure of arterial oxygen to fraction of inspired oxygen (PaO2/FIO2) improved in proportion to the decrease in LDH level.

Conclusions: Patients with Chinese medicine-induced acute lung injury exhibited ARDS. However, their prognosis was satisfactory, which suggests that a hypersensitivity reaction or a permeability oedema with minimal epithelial injury may be involved in the pathophysiology.