[Mycobacterium xenopi lung infection in a patient with multiple lung cysts that responded well to chemotherapy: a case report].

An abnormal shadow was observed on the chest radiograph of a 39-year-old man during health examination. The chest CT scan showed a consolidation around the cysts in the left upper lobe. The patient was diagnosed with Mycobacterium xenopi lung infection based on the presence of acid-fast bacilli in the sputum culture several times, which were identified as Mycobacterium xenopi by DNA-DNA hybridization. Two weeks after the initation of chemotherapy with 4 drugs (isoniazid, rifampicin, ethambutol, and clarithromycin), the patient's sputum smear and culture test results were negative; additionally, the consolidation on the chest CT scan improved after 10 months of treatment. There have been several case reports on Mycobacterium xenopi lung infection in Japan. However, few have studied Mycobacterium xenopi lung infections associated with multiple lung cysts that responded well to chemotherapy are rare.

Clinical features of organizing pneumonia in anti-aquaporin-4 antibody-positive neuromyelitis optica spectrum disorders.

BACKGROUND: Anti-aquaporin-4 (AQP4) antibody is an autoantibody marker often observed in patients with neuromyelitis optica spectrum disorder (NMOSD). The pathological relevance of complicated pulmonary disorders in anti-AQP4 antibody-positive NMOSD remains unclear. We aimed to assess the clinical and histological relevance of complicated pulmonary disorders in anti-AQP4 antibody-positive NMOSD. METHODS: We retrospectively reviewed the medical records of 52 patients with anti-AQP4 antibody-positive NMOSD and conducted immunohistochemical evaluations of the lung biopsy specimens. RESULTS: Among 52 patients with anti-AQP4 antibody-positive NMOSD, 4 patients showed pulmonary involvement with a diagnosis of organizing pneumonia (OP). The proportion of males was larger (75% vs. 12.5%; p = 0.013) and creatine kinase levels were higher (458.3 U/L vs. 83.9 U/L; p = 0.003) in patients with OP than in those without OP. OP development preceded or coincided with the NMOSD symptoms. Chest computed tomography findings were consistent with OP in all four patients. Bronchoalveolar lavage fluid predominantly contained lymphocytes. Transbronchial lung biopsy revealed intraluminal plugs of inflammatory debris within the alveoli. Alveolar epithelial cells covering the OP lesions exhibited AQP4 loss, immunoglobulin G deposition, and complement activation. Corticosteroid treatment resulted in clinical improvement of OP. CONCLUSION: OP may be considered a pulmonary manifestation of anti-AQP4 antibody-positive NMOSD beyond the central nervous system. Complement-dependent cytotoxicity of the lung epithelial cells caused by anti-AQP4 antibody is at least partly involved in OP development. When diagnosing NMOSD, the possibility of OP should be carefully evaluated based on the detailed history and chest imaging findings.

Pancreatic tuberculosis in an immunocompetent young female mimicking a malignant tumor: A case report and diagnostic radiological investigation.

Tuberculosis remains the leading cause of infectious disease related death worldwide with extrapulmonary tuberculosis being particularly difficult to diagnose. Here, we report a case of pancreatic tuberculosis (PTB) in an immunocompetent young female, which mimicked a malignant tumor diagnosed by endoscopic ultrasound-guided fine needle aspiration and biopsy (EUS-FNAB). A 19-year-old Japanese female with no prior medical history presented with abdominal epigastralgia and appetite loss lasting 2 months. A solid lobular mass was observed in the pancreatic head with enhanced abdominal computed tomography and magnetic resonance imaging suggested it was a malignant pancreatic tumor. Using EUS-FNAB, granulomas with caseous necrosis and acid-fast bacilli were observed. Polymerase chain reaction results were positive for Mycobacterium tuberculosis but negative for Mycobacterium avium complex. Therefore, the patient was diagnosed with PTB. Her symptoms and radiological findings improved with a standard antituberculosis therapy. PTB is difficult to differentiate from other pancreatic diseases with Magnetic resonance imaging (MRI) patterns of T1, T2 weighted, or diffusion-weighted image (DWI) images. To investigate novel radiological diagnostics for PTB, we focused on MRI apparent diffusion coefficient (ADC) values, which have not been investigated in this context. The present case showed 0.52 × 10-3 mm2/s; additionally, the mean value of other mass-forming pancreatic diseases, such as pancreatic cancer was 1.592 × 10-3 mm2/s (the range: 1.015-3.025 × 10-3 mm2/s). The range does not overlap with the present PTB case or other pancreatic diseases. Therefore, ADC values may be useful as a noninvasive radiological diagnostic method for PTB.

A 72-Year-Old Woman With Respiratory Failure and Bilateral Ground-Glass Opacities.

A 72-year-old woman with diabetes mellitus was admitted to our hospital because of dyspnea on exertion. Sputum cytologic evaluation revealed intranuclear inclusion bodies in the cells; we therefore considered viral pneumonia and performed a bronchoscopy. The bronchial washing fluid was positive for immunoperoxidase staining of herpes simplex virus type 1 (HSV1) and HSV1 polymerase chain reaction. The patient was diagnosed as having pneumonia due to HSV1 and was successfully treated with acyclovir.

Pembrolizumab-induced Ocular Myasthenia Gravis with Anti-titin Antibody and Necrotizing Myopathy.

A 73-year-old man developed diplopia after the administration of pembrolizumab for lung adenocarcinoma. He had ptosis and external ophthalmoplegia without general muscle weakness. Serum CK levels were elevated. Although autoantibodies to acetylcholine receptor and muscle-specific kinase, the edrophonium test, and the repetitive nerve stimulation test were all negative, anti-titin autoantibody was positive, leading to the diagnosis of myasthenia gravis (MG). Muscle pathology showed necrotizing myopathy with tubular aggregates. Unlike previously reported cases of pembrolizumab-associated MG, the present case showed ocular MG. This is the first case of pembrolizumab-associated MG with anti-titin antibody, as well as the first case with tubular aggregates.

Retrospective study of the predictors of mortality and radiographic deterioration in 782 patients with nodular/bronchiectatic Mycobacterium avium complex lung disease.

OBJECTIVES: Some patients with nodular/bronchiectatic Mycobacterium avium complex lung disease (NB MAC-LD) deteriorate and die. The main aim of the study is to evaluate the prognostic factors and radiographic outcomes in patients with NB MAC-LD. SETTING: Retrospective single-centre review. PARTICIPANTS: 782 HIV-negative patients with NB MAC-LD treated at our institution in Japan. PRIMARY AND SECONDARY OUTCOME MEASURES: All-cause and MAC-LD progression mortality rates and the prognostic factors, and radiographic deterioration rates and the prognostic factors. RESULTS: Mean age was 68.1 years, and median follow-up period was 4.3 years. Death from any cause and progression of MAC lung disease (MAC-LD) occurred in 130 (16.6%), and 19 (2.4%) patients, respectively. All-cause and MAC-LD progression 10-year mortality rates were 27.4% and 4.8%, respectively. In 536 patients with MAC-LD who were followed-up for more than 1 year, radiographic deterioration occurred in 221 (41.2%) patients and median time-to-radiographic deterioration was 9 years. A multivariate Cox proportional hazard model showed male sex, older age, body mass index <18.5 kg/m(2), absence of bloody sputum, hypoalbuminaemia and erythrocyte sedimentation rate >40 mm/h to be negative prognostic factors for all-cause mortality, and the presence of idiopathic pulmonary fibrosis, haemoglobin <11.3 mg/dL, C reactive protein >1.0 mg/dL and the presence of cavity to be negative prognostic factors for radiographic deterioration. CONCLUSIONS: Only 2.4% of patients with NB MAC-LD died from MAC-LD progression. As clinical trials testing the effectiveness of drug therapy in patients with NB MAC-LD are being designed and implemented, the primary end point could be time-to-radiographic deterioration, and trial patients need to be stratified according to these prognostic factors before randomisation.

Deterioration of the immune response induced by sulfamethoxazole-trimethoprim in a rheumatoid arthritis patient with Pneumocystis jirovecii pneumonia.

A 73-year-old woman with rheumatoid arthritis treated with methotrexate and prednisolone was admitted with dyspnea and ground-glass opacity on chest CT. We diagnosed her with Pneumocystis jirovecii pneumonia (PCP) based on a positive PCR analysis of Pneumocystis jirovecii and the presence of cysts in bronchoalveolar lavage fluid. The PaO2 was 74.7 Torr on room air, and treatment with sulfamethoxazole-trimethoprim only was initiated. The hypoxemia and ground-glass opacity increased on hospital day 3, and the administration of adjunctive steroid therapy resulted in an improvement in the patient's condition. Although patients with PCP with HIV infection and hypoxemia are often treated with adjunctive steroid therapy to prevent adverse immune reactions, the efficacy of additive steroid administration in case of non-HIV PCP has not been established.

Medical thoracoscopy performed under local anesthesia is useful for diagnosing pleural metastasis of renal cell carcinoma.

A patient with a past history of renal cell carcinoma (RCC) presented to us with an exudative pleural effusion. Because pleural effusion cytology was inconclusive, we performed medical thoracoscopy under local anesthesia. Multiple white tumors measuring approximately 2 cm in diameter were observed on the parietal pleura. Metastatic carcinoma from RCC was diagnosed histologically. Although malignant effusions are rare in cases of RCC metastasis, clinicians should be aware of this possibility. When pleural effusion cytology is inconclusive in a patient with a past history of RCC, medical thoracoscopy can be useful for making the diagnosis of pleural metastasis.