Background: Spontaneous pneumomediastinum (SPM) usually occurs in young people without an apparent precipitating factor or disease. Although there have been many studies focused on the clinical features and standard chest X-ray (CXR) findings of SPM, few have reviewed the chest computed-tomographic (CT) findings. Objectives: We assessed SPM using CXR and CT, and the relation between them. Methods: We evaluated 33 patients (26 males) diagnosed with SPM on the basis of symptoms and chest radiological findings. Results: Three patients showed normal CXR but a diagnostic CT scan. Seven showed mild pneumomediastinum on CXR. In these 10 patients, pneumomediastinum was easily detected by chest CT. Moderate and severe SPM were easily detected by both CXR and CT. Conclusions: These findings suggested that CXR alone poorly detected approximately 30% of SPM and that chest CT scan was needed to make the diagnosis in these cases. It seems likely that SPM is underdiagnosed by 30% or more in clinical practice.

We have studied the pharmacokinetics of amphotericin B (AmB) in lung lymph circulation and bronchial-wash fluid after intravenous infusion and inhalation, respectively. For two experiments with awake sheep, we used lung lymph fistulas and tracheotomy. In experiment 1, AmB concentrations in plasma and lung lymph after intravenous infusion of AmB (1 mg/kg of body weight) over 1.5 h were measured. The mean peak in plasma level was 756.0 ± 188.8 ng/ml at 3 h after the start of infusion, and the level then decreased gradually to 194.8 ± 28.9 ng/ml at 24 h. The stable and maximal levels in lung lymph last 5 to 9 h after the start of AmB infusion. The concentrations in lung lymph after 9 h were slightly higher than those in plasma. Thus, the lung lymph-to-plasma ratio of AmB concentrations increased gradually during infusion, and the ratio was more than 1.0 after the end of infusion, suggesting that AmB could be easily moved from plasma to pulmonary interstitium and/or lung lymph circulation. In another experiment, 5 or 30 mg of aerosol AmB was inhaled, and the concentration of AmB in the bronchial-wash fluid was determined by bronchoalveolar lavage. The peak AmB concentration in the fluid was observed at 0.5 h. After that, AmB was slowly eliminated over 24 h. The area under the concentration-time curve for 30 mg of inhaled AmB was higher than that for 5 mg, but maximum concentrations of AmB in serum for 5 and 30 mg were almost similar. These observations identify the pharmacokinetic characteristics of AmB in the lung and may provide a new insight into the strategy for clinical treatment of fungal pneumonia.

We report a rare case of Churg-Strauss syndrome (CSS) in a 41-year-old Japanese man with a history of middle-age onset of bronchial asthma who had severe abdominal pain. He presented with ileus caused by an annular ulcer of the ileum, attributable to mucosal ischemia resulting from necrotizing vasculitis of the mesenteric artery. He also had marked hypereosinophilia (51.5%), elevated serum IgE levels (34040 IU/ml), and generalized enlargement of the superficial cervical lymph nodes, containing eosinophilic granulomas. A stenotic lesion caused by an annular ulcer in the ileum was found and resected by laparotomy. Microscopic examination of the resected specimen revealed luminal narrowing or occlusion of small arteries in the ulcer base, subserosa, and mesenterium resulting from marked fibrotic intimal thickening with fragmentation or lack of the internal elastic lamina. These findings were diagnosed as vasculitis, scar stage. The postoperative course was uneventful, with the patient receiving a maintenance dose of prednisolone (10-15 mg/day) for 7 years subsequently. We must carefully diagnose and treat patients with middle-age onset asthma, because the symptom may be a lung manifestation of CSS, in which various organs including gastrointestinal tract are involved as a result of systemic necrotizing vasculitis.

This study evaluates the effect of direct hemoperfusion (DHP) using polymyxin B-immobilized fibers (PMX-F) as an extracorporeal blood filter on systemic hypotension and lung injury during endotoxemia Sheep were anesthetized, intubated, mechanically ventilated with 50% oxygen and connected to the DHP system between the right femoral artery and left jugular vein. Group 1 (n = 6)sheep were infused with 10 microg/kg Escherichia coli endotoxin over a 30 min period. At the same time, sheep underwent DHP with PMX-F (Toraymyxin: PMX-20R) for 2 h at a flow rate of 60 ml/h. Group 2 (n = 6) sheep were infused with the same dose of endotoxin and treated with a sham column, in the same manner as those in group 1. DHP with PMX-F significantly improved and restored systemic pressure and arterial oxygen tension in group 1 sheep, although these values never returned to the baseline levels of group 2 sheep. Pulmonary hypertension and leukocytopenia were observed after endotoxin infusion in both groups, but there were no significant differences between these values. DHP with PMX-F significantly decreased the elevation of plasma nitric oxide products. The treatment with PMX-F improves shock and deteriorated oxygenation during endotoxemia, probably through the suppression of nitric oxide production.

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