A 47-year-old man was referred to our hospital because of a 2-month history of dry cough, 2-kg weight loss, and a feeling of abdominal fullness. The PET-CT scan depicts the intense standard uptake values (SUVs) of the anterior and subphrenic lymphnodes, and intraperitoneal cavity, especially in the omentum, while, no uptake was found in the pleural cavity. Based on the pathological findings of the open lung biopsy specimens, he was diagnosed with malignant peritoneal mesothelioma of epithelioid type with thoracic metastasis. The present case demonstrated the some of the limitations of PET-CT in the diagnosis of malignant mesothelioma, which failed to detect pleural involvement despite aggressive invasion by this tumor.

Background

Opportunistic pulmonary infection with Nocardia species is rare in humans, and only a few studies have radiologically analyzed patients with pulmonary nocardiosis using high-resolution computed tomography (HRCT).

Methods

We retrospectively reviewed the medical records of patients with pulmonary nocardiosis at our hospital between April 2006 and December 2011 to assess HRCT and clinical findings. We also searched the medical literature for pulmonary nocardiosis reported in Japan between 2002 and 2011 for comparison.

Results

We identified seven patients at our institution and 33 reported infections in Japan. Four of our patients were immunocompetent, whereas the other three had impaired cellular immunity due to type 2 diabetes mellitus or having been inappropriately treated with steroid. Thoracic HRCT revealed no zonal predominance, but tropism for distribution from the middle to the peripheral area, and radiological findings of nodules, cavitation, mass, consolidations, bronchial wall thickening, septal line thickening and ground glass opacity (GGO) were evident. The main HRCT finding in our study comprised nodules (n=5, 71.4%) <30 mm and four patients had multiple nodules as described in other reports. Furthermore, we discovered a crazy paving appearance (CPA) around nodules, cavities, masses or consolidations in five patients (71.4%).

Conclusions

Multiple nodules distributed from the middle to the peripheral area on HRCT might reflect pulmonary nocardiosis, and CPA seemed to be a worth paying attention to the diagnosis.

We studied the molecular evolution of H gene in four prevalent Asian genotypes (D3, D5, D9, and H1) of measles virus (MeV). We estimated the evolutionary time scale of the gene by the Bayesian Markov Chain Monte Carlo (MCMC) method. In addition, we predicted the changes in structure of H protein due to selective pressures. The phylogenetic tree showed that the first division of these genotypes occurred around 1931, and further division of each type in the 1960–1970s resulted in four genotypes. The rate of molecular evolution was relatively slow (5.57×10−4 substitutions per site per year). Only two positively selected sites (F476L and Q575K) were identified in H protein, although these substitutions might not have imparted significant changes to the structure of the protein or the epitopes for phylactic antibodies. The results suggested that the prevalent Asian MeV genotypes were generated over approximately 30–40 years and H protein was well conserved.

Background

The saw-tooth sign was first described by Sanders et al in patients with obstructive sleep apnea syndrome as one cause of extrathoracic central airway obstruction. The mechanism of the saw-tooth sign has not been conclusively clarified. The sign has also been described in various extrathoracic central airway diseases, such as in burn victims with thermal injury to the upper airways, Parkinson’s disease, tracheobronchomalacia, laryngeal dyskinesia, and pedunculated tumors of the upper airway.

Case presentation

A 61-year-old man was referred to our hospital with a two-month history of persistent dry cough and dyspnea. He was diagnosed with lung cancer located in an intrathoracic central airway, which was accompanied by the saw-tooth sign on flow-volume loops. This peculiar sign repeatedly improved and deteriorated, in accordance with the waxing and waning of central airway stenosis by anti-cancer treatments.

Conclusion

This report suggests that the so-called saw-tooth sign may be found even in intrathoracic central airway obstruction due to lung cancer.

Rationale: Inhaled granulocyte/macrophage–colony stimulating factor (GM-CSF) is a promising therapy for pulmonary alveolar proteinosis (PAP) but has not been adequately studied.

Objectives: To evaluate safety and efficacy of inhaled GM-CSF in patients with unremitting or progressive PAP.

Methods: We conducted a national, multicenter, self-controlled, phase II trial at nine pulmonary centers throughout Japan. Patients who had lung biopsy or cytology findings diagnostic of PAP, an elevated serum GM-CSF antibody level, and a PaO2 of less than 75 mm Hg entered a 12-week observation period. Those who improved (i.e., alveolar–arterial oxygen difference [A–aDO2] decreased by 10 mm Hg) during observation were excluded. The rest entered sequential periods of high-dose therapy (250 μg Days 1–8, none Days 9–14; × six cycles; 12 wk); low-dose therapy (125 μg Days 1–4, none Days 5–14; × six cycles; 12 wk), and follow-up (52 wk).

Measurements and Main Results: Fifty patients with PAP were enrolled in the study. During observation, nine improved and two withdrew; all of these were excluded. Of 35 patients completing the high- and low-dose therapy, 24 improved, resulting in an overall response rate of 62% (24/39; intention-to-treat analysis) and reduction in A–aDO2 of 12.3 mm Hg (95% confidence interval, 8.4–16.2; n = 35, P < 0.001). No serious adverse events occurred, and serum GM-CSF autoantibody levels were unchanged. A treatment-emergent correlation occurred between A–aDO2 and diffusing capacity of the lung, and high-resolution CT revealed improvement of ground-glass opacity. Twenty-nine of 35 patients remained stable without further therapy for 1 year.

Conclusions: Inhaled GM-CSF therapy is safe, effective, and provides a sustained therapeutic effect in autoimmune PAP.

Clinical trial registered with www.controlled-trials.com/isrctn (ISRCTN18931678), www.jmacct.med.or.jp/english (JMA-IIA00013).