A 54-year-old Japanese man started to take oren-gedoku-to, a type of JHM, because it had been prescribed by a local clinic on Day 1 for the hot flashes he had been experiencing for 2 years. He developed a high fever and chills after taking oren-gedoku-to for 17 days. After developing dyspnea mainly when exercising, he decided to stop taking the medication on Day 17. A few weeks later he was admitted to his local clinic with symptoms of dyspnea on exercise, malaise and chills. When admitted to our hospital on Day 21, he was afebrile, and slight fine crackles were heard in his lower back.
Chest X-ray showed interstitial shadows in both lower lung fields, and computed tomography (CT) showed diffuse patchy and funicular opacities and volume loss predominantly in both lower lung areas (Fig. 1). Peripheral leukocyte and eosinophil counts were 6,500 cells/muL and 436 cells/muL, respectively, and the serum C-reactive protein level was 2.31 mg/dL. The hepatic transaminase levels (AST 41 U/L, ALT 39 U/L) were mildly elevated with slight elevation of the lactate dehydrogenase level (267 U/L), and KL-6 was within the normal ranges but SP-D was elevated (Table 1). The SpO2 was low at around 85% after minor exertion. Restrictive impairment and decreased single-breath diffusing capacity for carbon monoxide were demonstrated by pulmonary function tests. Lymphocytes and eosinophils were dominant (73.6% and 12.6% respectively), and the CD4/CD8+T-cell ratio was low in the bronchoalveolar lavage fluid (BALF) obtained on Day 25 (Table 1). Many alveolar macrophages existed, and mild lymphocytic interstitial inflammation was seen in the transbronchial lung biopsy (TBLB) specimens taken from the right middle and lower lungs (Fig. 2).
Although antibiotics and steroids were not administered, malaise, cough, hypoxemia and interstitial shadows gradually decreased up to Day 33. The patient was discharged from hospital on Day 43; the total hospitalization duration was 23 days (Fig. 3). We suspected that the patient had developed hypersensitivity pneumonitis from the Japanese summer, but he had no remarkable inhalation history, and there were no reports of deterioration in his housing conditions. After the patient stopped taking oren-gedoku-to, his fever and respiratory symptoms did not recur. Because lymphocytes obtained from the peripheral blood were positive in the DLST for oren-gedoku-to, we diagnosed him as having oren-gedoku-to-induced pneumonitis.
The JHM oren-gedoku-to, which is a mixture of four crude drugs-oren, ougon, oubaku and sanshishi-is often prescribed for hot flashes. We therefore next performed a DLST for each component, and only ougon was positive, resulting in a final diagnosis of ougon-induced pneumonitis (Table 2). His symptoms as well as radiograph findings and oxygenation recovered almost completely, and his peripheral eosinophil count returned to normal. Pulmonary function test findings also returned to normal, and his single-breath diffusing capacity for carbon monoxide recovered by Day 56 without using steroids or other anti-inflammatory drugs (Fig. 3).