{'fraction_non_alphanumeric': 0.03314836448598131, 'fraction_numerical': 0.018691588785046728, 'mean_word_length': 5.643064985451018, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 1, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Mycobacterium avium complex-induced pleurisy in a patient with amyopathic dermatomyositis and interstitial lung disease after prolonged immunosuppressive therapy.

Patients with amyopathic dermatomyositis (ADM) show the hallmark of cutaneous manifestations of dermatomyositis without detectable muscle abnormalities. The characteristic skin signs include Gottron papules, heliotrope rash, periungual erythema, and mechanic’s hands. Pulmonary involvement is well known in this disorder in which interstitial lung disease (ILD) is most commonly noted but pleural effusion is rarely reported. ILD associated with ADM can present as a rapidly progressive pattern, and intensive immunosuppressive drug therapy is required to prevent a fatal outcome or severe complications, such as respiratory failure. Mycobacterium avium complex (MAC) is one of the most common slow-growing nontuberculous species that can cause human lung disease. MAC-induced pulmonary infection is increasing worldwide, especially in immunocompromised hosts or in the patients with preexisting lung disease. Cavitary lung disease and nodular bronchiectasis are common in MAC-induced lung disorder, but pleural effusion is rarely found. Herein we report an unusual case of MAC-induced pleurisy in a patient with ADM and ILD after prolonged immunosuppressive therapy. A 45-year-old woman was admitted to our hospital in April 2005 with complaints of polyarthritis, heliotrope rash, Gottron papules, and periungual erythema. Nail-fold capillaroscopy examination disclosed the characteristic findings of dermatomyositis including giant capillary loops with avascular areas, disorganization of capillary distribution, and capillary hemorrhage. There was no myalgia or muscle weakness, serum creatine kinase levels were normal, and electromyography study did not detect myopathic changes on 2 different occasions (April 2005 and December 2005). Laboratory tests, including complete blood count, liver/renal function tests, blood glucose, and lipid profile were all within normal limits. The antibody (Ab) profiles of antinuclear Ab (ANA), antidsDNA Ab, anti-Smith Ab, anti-RNP Ab, anti-Jo-1 Ab, antiSCL-70 Ab, and rheumatoid factor were all negative. At that time, the plain x-ray and high resolution computed tomography of the chest disclosed interstitial pneumonitis in the lower lung fields. The lung diffusion capacity of carbon monoxide was mildly impaired, with carbon monoxide diffusing capacity DLCO/vital capacity (VC) being 84% of predicted value. On the basis of the above data, a diagnosis of ADM with lung involvement was made. From May 2005 to September 2005, monthly pulse methylprednisolone therapy (1 g 3 days/mo) was given for the progressive dyspnea, deterioration of DLCO/VC to 71%, and increased lung reticular infiltrations. Clinical symptoms improved after corticosteroid pulse therapy. Thereafter, she refused to take any medication until February 2006 when dyspnea recurred. The repeated high resolution computed tomography of chest revealed new pulmonary infiltrations in both the lower and upper lung fields; also, some suspicious cavitylike lesions in the peripheral lower lobes were noted. In March 2006, video-assisted thoracoscopic surgery with wedge resection of the right upper lobe and right lower lobe was performed, and organizing pneumonia was found in the pathologic studies, in which acute and chronic inflammatory cell infiltration with some intra-alveolar fibroblastic plugs or intra-alveolar histiocytic aggregation were found. Mycobacteria, bacterial, and fungal infections were excluded by culture, acid-fast stain, and polymerase chain reaction. Because there was no clinically significant respiratory distress after this biopsy, she refused to take any medication again until March 2007, when polyarthralgia, dermatomyositis skin rashes, and dyspnea resumed. Monthly pulse intravenous cyclophosphamide (300 mg/ mo) and monthly pulse methylprednisolone (1 g 3 days/mo) were given from March 2007 to June 2007. After this treatment, the patient’s dyspnea improved greatly, and the previous peripheral lung infiltrations, including cavity-like lesions in lower lungs, soon resolved; however, pleural effusion in the left lung developed in July 2007. Thoracentesis from the left pleural space yielded yellowish, lymphocyte-predominant exudative fluid, in which malignant cells and microorganisms, including Mycobacterium tuberculosis, were not found. Because of the increased amount of left-sided pleural effusion (Fig. 1) and aggravated dyspnea, pleural biopsy was performed in September 2007; chronic granulomatous inflammation (Fig. 2) with acid-fast bacilli also found. The pleural fluid grew MAC in November 2007. TB-polymerase chain reaction studies of the pleural fluid and pleura tissue were all negative. Combination therapy with levofloxacin, rifabutin, and ethambutol was started in December 2007 and pleural effusion soon improved. MAC is the most common cause of nontuberculous mycobacterium (NTM)-induced lung diseases. Patients with preexisting lung disease or those in an immunocompromised status are at higher risk of developing this kind of infection. The clinical symptoms and signs of MAC pulmonary infection are variable and nonspecific. Productive cough and shortness of breath are common, but fever and weight loss are less frequently noted, as compared with the typical pulmonary tuberculosis. The common radiologic features of MACinduced lung diseases are cavities in the upper lobes and nodular bronchiectasis with a predilection for the lingual or right middle lobe; pleural effusion is rarely found in this disorder. 4 NTM can be found in the pleural effusion of patients with congestive heart failure or metastastic cancer. In a retrospective study of 22 patients with NTM isolated from pleural fluids, 16 (72%) cases, of which 5 underwent pleural biopsy, were considered to be contamination rather than true infection, because no simultaneous extra pleural infection focus or pleural granuloma was found. Distinguishing between contamination From the *Division of Allergy, Immunology, and Rheumatology, Department of Medicine, †Department of Chest Medicine, and ‡Department of Pathology and Laboratory Medicine, Taipei Veterans General Hospital, Taiwan, Republic of China; §Section of Allergy, Immunology, and Rheumatology, Buddhisht Tzu-Chi General Hospital, Hualien, Taiwan, Republic of China; and ¶National Yang-Ming University, Taiwan, Republic of China. Correspondence: De-Feng Huang, MD, Division of Allergy, Immunology, and Rheumatology, Department of Medicine, Taipei Veterans General Hospital, 201, Section 2, Shih-Pai Road, Taipei, 112, Taiwan, Republic of China. E-mail: dfhuang@vghtpe.gov.tw Copyright © 2009 by Lippincott Williams & Wilkins ISSN: 1076-1608/09/1504-0193 DOI: 10.1097/RHU.0b013e3181a76fca