Mycobacterium kansasii pulmonary infection: CT findings in 29 cases.

PURPOSE: Our aim was to assess computed tomography (CT) features of Mycobacterium kansasii pulmonary infection (M. kansasii infection). MATERIALS AND METHODS: A total of 29 cases confirmed to have M. kansasii infections were analyzed. The main locations of pulmonary changes, incidence, and various imaging features of the cavity (location, maximum diameter, wall thickness, satellite nodules, intracavitary fluid), and other imaging findings such as nodules, consolidation, and bronchiectasis, were visually assessed on CT images. RESULTS: Locations of the main abnormalities were as follows: right S2 41%; right S1 31%; left S1+S2 2: 21%. A total of 49 cavities were observed in 24 (83%) cases. The mean maximum diameter, wall thickness, and ratio of wall thickness to the maximum diameter were 33.0 mm, 4.7 mm, and 0.19, respectively. Shapes of the cavities were round in nine (18.4%), oval in 17 (34.7%), and tubular/meandering in 23 (47%). Satellite nodules were found in only 30.6% of patients (n = 15). Small nodules were found in 26 (89.7%) patients, and most of them showed a centrilobular distribution. CONCLUSION: The characteristic CT findings suggestive of M. kansasii infection include cavities located in the right posterior or apical segment with a tubular/meandering shape and a thin wall.

[A case of primary lung cancer with swollen mediastinal lymph nodes due to pre-existing sarcoidosis].

A 69-year-old man, who had been followed up for sarcoidosis at another hospital from 10 years previously, was referred to our hospital because of a new lesion in the left upper lobe. A chest CT scan revealed a nodular lesion at the orifice of the left B3b and mediastinal lymphadenopathy. Bronchoscopic biopsy established a diagnosis of squamous cell carcinoma. Because there had been no distant metastasis and no change in size of the mediastinal lymph nodes over the previous 5 years, left upper lobectomy with lymph node dissection was performed. The histology of the resected tumor indicated a moderately-differentiated squamous cell carcinoma, and the dissected lymph nodes contained non-caseous epithelioid cell granuloma without metastasis. Thus, we made a final diagnosis of squamous cell carcinoma (pT1N0M0, stage IA) that complicated the sarcoidosis. Surgical resection can be the first option for lung cancer complicating sarcoidosis with mediastinal lymphadenopathy, because making a preoperative assessment of N status is difficult.

[A case of bronchocentric granulomatosis resembling lung cancer on diagnostic imaging].

A 51-year-old man visited a local physician because of a chest radiographic abnormality which had been pointed out in October 2009 and March 2010. His chest CT images revealed a nodular lesion in the right middle lobe. Since the nodular lesion showed abnormal FDG accumulation on FDG-PET, the physician suspected lung cancer, but was unable to make a definitive diagnosis by CT-guided lung biopsy. The patient was thus referred to our hospital for detailed investigations. A nodular lesion with spiculation and pleural indentation was recognized in the S4 region on chest CT scans which was strongly suspected to be lung cancer. Since various examinations did not provide a definitive diagnosis, we performed surgery. The histological findings of the extirpated tumor were considered to be bronchocentric granulomatosis (BCG), because necrotic granulomatous lesions with epithelioid cells centered on the bronchioles and there was no evidence of fungus or acid-fast bacterium infection.

[Two cases of pulmonary amebiasis].

CASE 1: A 74-year-old man having a week's fever and diagnosed with a liver abscess was treated with several antibiotics and percutaneous liver drainage. His respiration gradually worsened and chest computed tomography (CT) showed right pleural effusion and a left-lung mass. Percutaneous fine needle aspiration of the pulmonary mass detected Entamoeba histolytica. CASE 2: A 44-year old, zoo office worker admitted for fever and right chest pain was found in CT to have right pleural effusion and a mass with a liver abscess necessitating abscess drainage. Injected contrast medium detected a fistula connected to the right. Following surgical drainage, E. histolytica was detected from the resected lung. Both cases responded well to metronidazole.

[Two cases of anomalous systemic arterial supply to the basal segments of bilateral lungs].

We encountered two cases of systemic arterial supply to the basal segments of bilateral lung with elevated serum CEA levels. The patients were a 36-year-old man and a 30-year-old man with the abnormal chest shadows, discovered during physical checkups. A chest computed tomogram (CT) of the 36-year-old patient showed reticulonodular shadows in the bilateral lower lobe with anomalous vessels arising from the descending aorta and running into the lower lobe on each side, and his abdominal CT revealed a duplicated vena cava inferior. His aortogram confirmed an anomalous systemic arterial supply to the basal segments of bilateral lungs. The chest CT of the 30-year-old patient revealed a cystic lesion in the right lower lobe and no abnormality in the left lung field. His aortograms showed aberrant systemic arterial supplies to the bilateral lower lobe. Because the cystic lesion had increased in size, it was resected and an anomalous systemic artery was seen. Intralobar sequestration in the right lung and anomalous systemic arterial supply in the left lung was diagnosed. Serum CEA was high at the initial visit in each patient but it decreased spontaneously in the first patient, and after the resection of the cystic lesion in the second patient. We report two cases of anomalous systemic arterial supply to the basal segments of bilateral lung, which is extremely rare. Our literature search revealed that only 13 cases have been reported to date.

[Case of idiopathic pulmonary upper lobe fibrosis].

A 49-year-old man was referred to our hospital because of progressive volume reduction in bilateral upper lobes over 10 years. He was slim, with a straight back. Chest high-resolution computed tomography (HRCT) showed consolidation with small radiolucent areas in both upper lobes. Surgical biopsy by video-assisted thoracoscopy was performed in the right upper and lower lobes. The pathological findings of the upper lobe showed intraluminal fibrosis with alveolar collapse and proliferation of elastic fibers on the subpleural surface, but the lower lobe was normal. We diagnosed his illness as typical idiopathic pulmonary upper lobe fibrosis (IPUF), previously described by Amitani in 1992.

[Microscopic polyangiitis accompanied by interstitial pneumonia and abducens palsy].

A 69-year-old man was referred to our hospital with fever. Interstitial pneumonia and right pleural effusion were noted with elevated MPO-ANCA. Video-assisted thoracoscopic lung biopsy was performed and UIP -like histology was obtained. His symptoms and chest X-ray finding improved with administration of prednisolone and cyclosporine, but ten months later diplopia appeared. He had right abducens palsy and impaired perception in the first right trigeminal branch area, and we diagnosed mononeuritis multiplex due to microscopic polyangiitis.

[A case of ruptured bronchial artery aneurysm with hemothorax and mediastinal hematoma].

We encountered a case of ruptured bronchial artery aneurysm, which presented with hemothorax and mediastinal hematoma. The patient was a 65-year-old man. He was admitted because of a sudden onset of right chest pain. The chest X-ray film revealed a right pleural effusion and a pleural tap was reported to be bloody. Chest contrast CT revealed a subcarinal mass and several nodes, about 10 mm in diameter, in the thyroid. Because fine needle aspiration of the thyroid was positive, we suspected that the mediastinal lesion was a metastatic lymph node, and that the ruptured metastasis and carcinomatous pleurisy might have caused the hemothorax. However, mediastinoscopy confirmed no tumor but only mediastinal hematoma. This made us strongly suspect ruptured bronchial artery aneurysm. We next performed selective angiography of the bronchial artery, revealing an aneurysm, 10 mm in diameter. On this basis, a definitive diagnosis of ruptured bronchial artery aneurysm was made. Since the feeding vessel was too narrow to cannulate for embolization, we performed video-assisted thoracic surgery to dissect the hematoma. Although it was too organized to identify the aneurysm, it was assumed to be have been removed, and no recurrence was observed after the operation. Since a rupture of the bronchial artery could be life-threatening, a ruptured bronchial artery aneurysm should be considered as one of the differential diagnoses of hemothorax.

[Two cases of invasive pulmonary aspergillosis successfully treated with combination of antifungal agents].

Case 1 was a 53-year-old man with a past history of chronic pancreatitis, diabetes mellitus and left upper lobectomy for lung cancer, 3 years previously. He was admitted with fever and an abnormal consolidative shadow in the left upper lung field of his chest X-ray film. Aspergillus fumigatus and Aspergillus niger were detected in his sputum and bronchial washing. Case 2 was a 60-year-old man, in whom left upper lobectomy had been performed for lung cancer 7 years previously. He was admitted with cough and fever. His chest X-ray film showed consolidation with a cavitary lesion in the left upper lung field. Aspergillus fumigatus was detected in his bronchial washing. Each case was treated successfully with a combination of antifungal agents.

[A case of Sjögren syndrome with pulmonary nodular amyloidosis and pulmonary multiple cysts].

A 57-year-old woman who had been given a diagnosis of Sjögren syndrome at age 53 consulted a nearby doctor because of bloody sputum. He noted her chest abnormal shadows and referred her to our hospital. Her chest radiograph and high-resolution computed tomograph showed multiple nodules and cysts in both lung fields. Video-assisted thoracoscopic lung biopsy revealed patchy fibrosis, cystic change, AL type amyloid deposition and mild lymphoid hyperplasia and a diagnosis of Sjögren syndrome-associated-pulmonary-disease was established.

[A case of severe radiation pneumonitis--a trial of plasma exchange].

A 77-year-old man underwent radiotherapy for the squamous cell carcinoma of the right lung. Two months after the 60Gy/30fr irradiation was completed, he complained of dyspnea and his chest X-ray showed ground glass opacities and reticular shadows in both lung fields. Severe radiation pneumonitis was diagnosed. Two grams of methylprednisolone did not improve his symptoms and on the next day his hypoxemia worsened. We then tried plasma exchange because of his critical status. His respiratory status improved rapidly after plasma exchange and his chest X-ray showed remarkable improvement 10 days later. We think this case suggests the effectiveness of plasma exchange for severe radiation pneumonitis.

[A case of chronic aspiration pneumonia caused by juvenile brain stem tumor].

A 23-year-old man had been treated for repeated pneumonia from the age of 16. After a diagnosis of eosinophilic pneumonia at the age of 17, he had been given antibiotics and steroids. At the age of 23, he was referred to our hospital. Although he improved rapidly in response to antibiotic medication, his chest X-ray shadows did not improve. Video-assisted thoracoscopic lung biopsy was performed. Fibrosis and invasion of inflammatory cells were seen on the air duct walls and foreign bodies that were thought to be food residue were detected. A diagnosis of chronic aspiration pneumonia was made pathologically. A brain stem tumor was detected on his brain magnetic resonance imaging, which was thought to be the cause of his mis-swallowing.

[Two cases of summer-type hypersensitivity peumonitis with remarkable changes in the bronchioles].

A 56-year-old man and a 53-year-old woman with cough, sputum and dyspnea were admitted in the summer. High-resolution computed tomographic findings of the chest showed centrilobular branching opacities like diffuse panbronchiolitis with ground glass opacities. Both cases showed hypoxia, a high titer of serum anti-Tricosporon antibody and exacerbation in their own homes. Video-assisted thoracoscopic lung biopsy revealed granuloma in the bronchioles area. We diagnosed summer type hypersensitivity pneumonitis and this condition improved in response to antigen isolation and steroids. Remarkable changes in the bronchioles were characteristic in the two cases.

[A case of drug-induced pneumonitis due to Sai-rei-to].

The patient was given Sai-rei-to, adenosine triphosphate disodium and Mecobalamin on a diagnosis of sudden deafness. Forty days later, exertional dyspnea and cough appeared. He was given a diagnosis of bacterial pneumonia and was treated with several antibiotics. His respiratory state gradually worsened and he was refered to our hospital. His chest computed tomography scan showed ground-glass opacity, with consolidation, and laboratory data showed high values of white blood cell and liver dysfunction. After halting all medicines, he recovered. Because the lymphocyte stimulation test was positive for Sai-rei-to and he was still well after taking adenosine triphosphate disodium and Mecobalamin, we diagnosed drug-induced pneumonitis caused by Sai-rei-to.

[A case of myelodysplastic syndrome complicated with organizing pneumonia].

A 74-year-old man had been given a diagnosis of myelodysplastic syndrome (MDS), and had been treated with granulocyte-colony stimulating factor (G-CSF). 1 year later, he suffered from fever and his chest X-ray lung biopsy did not provide a diagnosis, video-assisted thoracoscopic lung biopsy was performed, which yielded a histological diagnosis of organizing pneumonia. His pulmonary disease was diagnosed as secondary organizing pneumonia due to MDS, and was treated successfully with steroids. Vigorous efforts to establish a histological diagnosis is needed for the antibiotics-resistant pneumonia in the case of MDS.

[Smear-positive pulmonary tuberculosis diagnosed in a general hospital].

In Japan, patients with smear-positive pulmonary tuberculosis (SPTB) are hospitalized in a sanatorium because of the law for the prevention of tuberculosis, and not in a general hospital. According to our experience, however, some of the patients with SPTB are hospitalized in a general hospital. In order to study if it is possible to prevent the admission of patients with SPTB to a general hospital, we retrospectively reviewed and compared the medical records of pulmonary TB patients whose sputum was smear-positive for Mycobacterium tuberculosis at our outpatient clinic (Group B; n = 61), and patients whose sputum was smear-positive after the admission to our hospital (Group A; n = 17). The Group A patients were significantly older than the Group B patients [mean age, Group A, 67 years vs Group B, 56 years; (p = 0.01)]. Compared with the Group B patients, the Group A patients more often suffered from underlying diseases [percentage of patients with underlying disease, Group A, 88.2% vs Group B, 37.7%; p < 0.001]; more often showed atypical infiltrative patterns of pulmonary tuberculosis [percentage of cases showing atypical chest roentgenograms, 70.6% vs 19.7%; p < 0.001]; and were in a more serious condition [percentage of deaths during treatment, 47.1% vs 1.7%; p < 0.001]. We conclude that hospitalization of SPTB patients in general hospitals is inevitable, because SPTB can not always be accurately diagnosed before admission, and because it is sometimes difficult to send severely ill SPTB patients to a sanatorium which is inconveniently located in the countryside. We propose to provide facilities for the treatment of SPTB at all general hospitals in Japan.