Solitary pulmonary nodule due to Cryptococcus neoformans and Mycobacterium tuberculosis

This report describes a rare combined infection of Cryptococcus neoformans and Mycobacterium tuberculosis that manifested as a solitary pulmonary nodule in a nonimmunocompromised patient. Transthoracic needle aspiration biopsy was initially nondiagnostic, and histopathologic and culture confirmation of the diagnosis was eventually attained after wedge resection of the nodule. An extensive review of the English literature failed to reveal any reported cases of such a combined infection with a similar clinical presentation. The variable morphologic features of C. neoformans in tissue sections and the protean histologic features of pulmonary cryptococcosis can lead to diagnostic difficulties, as illustrated by this case.     

Four cases of pulmonary Mycobacterium avium intracellulare complex presenting as a solitary pulmonary nodule and a review of other cases in Japan

OBJECTIVE: To evaluate clinical findings of patients with a solitary pulmonary nodule in Japan caused by pulmonary Mycobacterium avium complex (MAC) disease. METHODS: The authors investigated the clinical features of 12 patients diagnosed as having pulmonary MAC disease who had presented with a solitary pulmonary nodule. RESULTS: The causative microorganisms were M. avium in seven patients, Mycobacterium intracellulare in two and MAC in three. The diagnostic methods were bronchoscopic biopsy or percutaneous lung biopsy in three patients and surgical operations in the remaining nine. Eleven patients had a complete surgical resection of the nodule and antituberculous drugs were administered to eight. On X-ray, there was an absence of calcification, satellite lesions, cavities, or bronchoectasis that are often thought to be characteristic of pulmonary mycobacterial disease. Differentiation from lung cancer was thought necessary in five patients. There was no microbiological or radiological relapse in those who underwent complete surgical resection. CONCLUSIONS: Because treatment is often poorly effective for patients with pulmonary non-tuberculous mycobacterial disease, it is important to identify the causative microorganisms by performing a culture examination of resected lung tissue especially if there is a solitary pulmonary nodule.     

Mycobacterium intracellulare pulmonary infection which co-existed and mimicked lung cancer

We report a case of Mycobacterium intracellulare (M. intracellulare) pulmonary infection with co-existing lung cancer and presenting as a solitary pulmonary nodule requiring differentiation from lung cancer. Computed tomography showed two nodules (20 mm) with spicula formation and pleural indentation on the right lower lobe of the lung (right S6 and S8). Transbronchial biopsies from the right S6 and S8 nodules revealed mycobacteriosis and adenocarcinoma, respectively. Thereafter, a right lower lobectomy was performed. Cases of pulmonary M. intracellulare disease with solitary nodule are rare. Moreover, M. intracellulare pulmonary infection with co-existing lung cancer is extremely rare.     

A case of pulmonary Mycobacterium intracellulare infectious disease with a solitary pulmonary nodule in the peripheral lung field]

A 63-year-old woman was admitted to our hospital because of a solitary nodule (20 x 20 mm) in the right S3 which was first detected during a health examination. Because radiological findings for the nodule, such as pleural indentation and spicula on chest CT led us to suspect a pulmonary adenocarcinoma, we could not completely rule out lung cancer and performed a bronchoscopic examination on the third day after admission. However, no definite diagnosis could be made. Therefore, video-assisted thoracic surgery (VATS) was performed, and a caseating epitheloid granuloma with acid-fast bacilli was found. Initially, we administered antituberculous drugs for pulmonary tuberculoma, but then changed to combined chemotherapy using RFP, EB, CAM and SM after identification of Mycobacterium intracellulare by a culture test of resected tissue. We report a rare case with a solitary nodule caused by pulmonary Mycobacterium intracellulare infectious disease which is indicative of lung cancer.     

Solitary pulmonary nodule due to Mycobacterium fortuitum

We report the case of an asthmatic man in whom a solitary pulmonary nodule was discovered after an episode of self-limited hemoptysis. Infection was suspected after initial response to empirical antibiotic therapy, and the pathogen was later identified to be a rare mycobacterium. The pulmonary nodule resolved without surgery after oral quinolone therapy. Mycobacterium fortuitum should be added to the list of possible causes of solitary pulmonary nodule in Spain.     

Cytomegaloviral infection presenting as a solitary pulmonary nodule.

Cytomegaloviral infection presenting in an immunologically compromised host as a solitary pulmonary nodule has not previously been reported. A patient with a renal transplant and with no pulmonary symptoms was noted to have a single nodule on a chest roentgenogram. At autopsy, this proved to be secondary to cytomegaloviral infection. Differential diagnostic considerations in the immunosuppressed patient are discussed.     

Solitary pulmonary granuloma caused by Mycobacterium avium-intracellulare complex.

OBJECTIVES: To analyse the clinical features and high resolution computed tomography (HRCT) findings of solitary pulmonary granulomas caused by the Mycobacterium avium-intracellulare (MAI) complex. METHODS: We retrospectively analysed a series of 73 consecutive patients with solitary pulmonary granuloma and negative sputum smear and culture results, in whom the diagnosis was established by histological examination of specimens obtained by partial pulmonary resection or lobectomy. We compared the clinical features and HRCT findings of the solitary pulmonary granulomas definitively diagnosed to be caused by the MAI complex with those of granulomas of other causes by univariate and multivariate analyses. RESULTS: In this study series of 24 patients with solitary pulmonary granuloma, the aetiological agent was established as being the MAI complex. According to the results of the multivariate analysis, 'female sex', 'pleural indentation' and 'lobulation' on the HRCT images were significantly associated with solitary pulmonary granuloma caused by the MAI complex. CONCLUSION: This study demonstrated several characteristics of solitary pulmonary granulomas caused by the MAI complex, and suggested that it might be a subtype of pulmonary MAI complex infection without the typical radiographic features of the infection.     

Case of recurrence of AA type primary solitary pulmonary amyloidosis]

The patient was a 64-year-old asymptomatic man. His chest X-ray film, at age 61, showed a solitary nodule in the right middle lobe. Thoracoscopic surgery was performed. The nodule was pathologically diagnosed as a solitary nodular amyloidosis. After 3 years, his chest CT showed a solitary nodule in the left upper lung. Thoracoscopic surgery for the pulmonary nodule was performed again, and it was also pathologically diagnosed as a solitary nodular amyloidosis with AA type amyloid protein. Solitary nodular pulmonary amyloidosis is usually AL type, and few cases of solitary AA type amyloidosis have been reported. We reported a rare case of recurrence of solitary pulmonary amyloidosis.     

Chronic solitary pulmonary nodule due to unsuspected pulmonary infarction from silent pulmonary embolism

Abstract A case of pulmonary embolism showing a longstanding solitary pulmonary nodule is presented. An asymptomatic 57 year-old man with a solitary nodule in the right lower lobe was referred to our hospital. A pulmonary perfusion-ventilation scan following a sudden onset of dyspnoea established the diagnosis of recurrent pulmonary embolism. The nodule gradually disappeared after anticoagulant treatment, indicating that the nodule was pulmonary infarction from silent pulmonary embolism. Although the incidence of pulmonary infarction is low in Japan, this case suggests that pulmonary infarction from silent pulmonary embolism should be considered as one important cause of a solitary pulmonary nodule.     

Tularemia--an unusual cause of a solitary pulmonary nodule in the post-transplant setting.

We report a case of tularemia presenting as a solitary pulmonary nodule following syngeneic PBSC transplant. Seven months after undergoing a syngeneic PBSC transplant for AML, our patient presented with fever without localizing signs. Chest X-ray revealed a solitary pulmonary nodule. Culture of a CT guided needle aspiration revealed Francisella tularensis. The patient was successfully treated with ciprofloxacin. His fever resolved and clearance of the nodule was documented on a CT scan 2 months after diagnosis and initiation of treatment. To our knowledge, this is the only reported case of tularemia occurring in the post-transplant setting. The possible relationship between transplant-induced immune dysfunction and the occurrence of this rare infection is discussed.     

Pulmonary Mycobacterium avium disease with a solitary pulmonary nodule requiring differentiation from recurrence of pulmonary adenocarcinoma

A 56-year-old man with a past history of surgical resection of a primary pulmonary adenocarcinoma in the right upper lobe was admitted to our hospital because of a rapidly increasing solitary nodule (50x30 mm) in the right S5 followed on the chest computed tomography (CT) for three months. Although we suspected recurrence of the pulmonary adenocarcinoma and performed a CT-guided lung biopsy, we could not make a definite diagnosis. Therefore, to rule out recurrence of the primary pulmonary adenocarcinoma completely, a partial surgical resection of the right middle lobe was performed and a caseating epitheloid granuloma with acid-fast bacilli was found. As the causative pathogen, Mycobacterium avium complex (MAC) disease should be considered in the differential diagnosis of a rapidly increasing solitary nodule through this peculiar case of pulmonary MAC disease.     

A solitary pulmonary nodule due to Mycobacterium gordonae

Mycobacterium gordonae is rarely pathogenic in humans. In this case it was cultured from the tissue of a resected pulmonary nodule in an immunocompetent patient. One year after completing 12 months of chemotherapy, the patient remains disease free. Atypical mycobacterium should be considered in the differential diagnosis of solitary pulmonary nodules.     

A case of pulmonary dirofilariasis that required differentiation from nontuberculous mycobacteriosis]

A 48-year-old man was admitted with an abnormal shadow on a chest X ray. Chest X ray and CT revealed a solitary nodule in the right lung field. Mycobacterium gordonae was cultured from sputum. Tumorectomy by video-assisted thoracoscopic surgery was done for histological diagnosis, and Dirofilaria worms accompanied with epithelioid cell granuloma with necrosis were found, while no bacteria were cultured from biopsy specimen, thus we diagnosed dirofilariasis. Because a solitary nodule can be caused by either Dirofilaria species or nontuberculous mycobacteria, this case was of interest with regard to the differential diagnosis of a lung solitary nodule.     

Primary pulmonary meningioma manifesting as a solitary pulmonary nodule with a false-positive PET scan

Primary pulmonary meningioma is very rare, with about 30 cases reported in the English literature. These lesions are usually benign, grow slowly, and have an excellent prognosis. However, they can mimic any other pulmonary tumor, as the most common presentation is as a solitary pulmonary nodule. We report a case of a primary pulmonary meningioma manifesting as a solitary lung nodule with a very high metabolic activity on the positron emission tomography, mimicking a primary lung cancer.     

Nontuberculous mycobacterial infections involving solitary pulmonary nodules]

Over the course of 11 years (1993-2003) we encountered 5 cases of pulmonary nontuberculous mycobacterium (NTM) involving a solitary pulmonary nodule. In this report we analyze the chest computed tomography (CT) of these patients, the utility of bronchoscope and transthoracic fine-needle aspiration techniques, the mycobacterium species involved, and treatment results. Four of the 5 NTM cases were due to infection with M. avium and one was due to infection with M. intracellulare. The characteristic findings of the chest CTs were as follows: A solitary nodule was present just under the pleura. No definite distribution pattern was evident. Some cases had agglutinated nodules or fine calcifications. Although fiberoptic bronchoscopy was not used as a diagnostic tool in all 5 NTM cases and histological samples did not contain granulomas, we determined the presence of NTM and we also verified that no cancer cells were present in any of the 5 NTM patients, using transthoracic fine-needle aspiration. Four out of the 5 NTM patients were treated only with drug therapy and they displayed clinical improvement. We resected a solitary nodule in one of the 5 NTM patients because of slow response to drug therapy. We conclude that the solitary pulmonary nodule of NTM is often due to M. avium and that transthoracic fine-needle aspiration is an easy and effective method of detecting NTM.     

Diagnostic approach to solitary pulmonary nodule

The solitary pulmonary nodule is a common radiologic abnormality that is often detected incidentally. Many malignant and benign diseases can present as a solitary pulmonary nodule on a chest roentgenogram. It is important to differentiate malignant nodules from benign nodules in the least invasive way and to make as specific and an accurate diagnosis as possible. In this paper, a diagnostic approach to the solitary pulmonary nodule was discussed.     

Idiopathic bronchiolitis obliterans with organizing pneumonia presenting with spontaneous hydropneumothorax and solitary pulmonary nodule

The first case of idiopathic bronchiolitis obliterans with organizing pneumonia (BOOP) presenting as solitary pulmonary nodule with spontaneous hydropneumothorax is reported in a 54-year-old man. A wedge resection of the right lower lobe was performed to show typical histological features of BOOP. This case report demonstrates that BOOP has a very diverse clinical manifestation and stresses the need to include solitary pulmonary nodule with hydropneumothorax in the spectrum of BOOP.     

孤立性肺结节病变性质临床鉴别诊断预测模型的初探

目的探讨孤立性肺结节的良恶性鉴别诊断的有效方法。方法回顾性分析44例孤立性肺结节患者的临床特点,血清学指标及其鉴别诊断效果,并建立临床预测模型。结果44例肺内孤立性结节患者中,恶性肿瘤占19例,良性肿瘤占25例。单因素分析结果患者的年龄、结节大小、结节边界、肿瘤病史、CEA、CA125及miR．21、miR-27b和miR-193b在良恶性孤立性肺结节患者间具有显著差异,多因素判别分析并建立Fisher线性判别函数,交互验证一致函数与原始个案的符合率为93％。结论除患者的一般情况、影像学表现和常规血清标记物外,microRNAs也是鉴别孤立性肺结节良恶性的良好指标,具有重要临床意义。     

Human pulmonary dirofilariasis: a case report and review of the recent Japanese literature

Human pulmonary dirofilariasis is a rare zoonotic infection caused by the dog heartworm Dirofilaria immitis, which is transmitted via a vector/intermediate host, generally the mosquito. The authors present a case of histologically diagnosed human pulmonary dirofilariasis, in which the lesion was resected using video-assisted thoracic surgery (VATS). The authors also review 24 cases of such zoonosis reported in Japan from 1998 to 2004. Of these 24 patients with human pulmonary dirofilariasis, 12 (50%) were men (mean age 54 years, range 29-80 years) and 67% were asymptomatic. Most patients (83%) had a solitary lung nodule, 95% of the lesions were <30 mm and 13% had a pleural effusion. VATS was performed to obtain a histopathological diagnosis in the majority (61%) of patients whom the authors reviewed. VATS would appear to be the best method for diagnosing pulmonary dirofilariasis.     

Estimating the probability of malignancy in solitary pulmonary nodules. A Bayesian approach

Decisions about managing solitary pulmonary nodules often involve estimates of the likelihood that the nodule is malignant. We used Bayes' theorem to devise a simple scheme for estimating the likelihood that a solitary pulmonary nodule is malignant based on the diameter of the nodule, the patient's age and history of cigarette smoking, and data on the overall prevalence of malignancy in solitary nodules. This method may improve the accuracy of estimating the likelihood of malignancy for individual patients with solitary pulmonary nodules.