A case of non-tuberculous mycobacteriosis with pleurisy with a past history of dense exposure to environmental asbestos

We report a case of non-tuberculous mycobacteriosis (NTM) with pleurisy in a 75-year-old man. The patient was admitted with a diagnosis of pneumonia. Chest radiography and CT scans revealed a tumorous shadow that increased rapidly in size despite treatment with antibiotics. Bronchoalveolar lavage fluid (BALF) disclosed numerous asbestos bodies, suggesting dense exposure and pulmonary silicosis. The tumorous chest shadow remained undiagnosed. Repeated microscopic examination of sputum and BALF revealed no acidophilic-bacilli. Diagnostic pneumonectomy was performed to further explore the nature of the tumorous shadow on chest radiography. Ziehl-Neelsen staining of excised lung tissue disclosed no acid-bacilli; however, the washed fluid of the tissue specimen showed acid-fast bacilli that were subsequently verified as M. avium by in vitro culture. The X-ray findings in our case were not consistent with NTM or specific for disease due to asbestos inhalation. A final diagnosis of NTM was confirmed via open biopsy of the lung. Our case suggests that in addition to tuberculosis, NTM should be taken into consideration as a complication of silicosis.     

Identification of a Novel NDM Variant,NDM-13, from a Multidrug-Resistant Escherichia coli Clinical Isolate in Nepal

A novel New Delhi metallo-β-lactamase, NDM-13, was identified in a carbapenem-resistant Escherichia coli clinical isolate obtained from the urine of a patient in Nepal. The enzymatic activity of NDM-13 against β-lactams was similar to that of NDM-1. However, NDM-13 displayed significantly higher k_cat/K_m ratios for cefotaxime. The genetic environment of bla_NDM-13 was determined to be tnpA-IS30-bla_NDM-13-ble_MBL-trpF-dsbC-cutA-groES-groL, with bla_NDM-13 located within the chromosome.     

Significance of Pseudomonas aeruginosa colonization of the gastrointestinal tract

OBJECTIVE: This study was conducted to determine the association between gastrointestinal (GI) colonization and the development of invasive Pseudomonas aeruginosa infections and risk factors for acquisition of P. aeruginosa colonization in gut. METHODS: All stool specimens sent for microbiological examination were cultured for P. aeruginosa search for three years. PATIENTS AND MATERIALS: P. aeruginosa had been isolated from stool of 207 patients for three years. Of the 207 patients, 87 patients were identified P. aeruginosa-colonized patients. RESULTS: Forty-five (52%) were exposed to previous invasive procedures and eighty-three (95%) were prescribed antibiotics before the isolation of P. aeruginosa. Fourteen distinctive P. aeruginosa infections were developed in 13 patients (15%). Infections associated with GI colonization included 4 pneumonia, 4 urinary tract infection, 3 skin infection, and 3 bacteremia. The age, gender, underlying diseases, previous invasive procedures, and the duration of hospitalization were not significant. Twelve (34%) patients were diagnosed with ileus and three (9%) were undergoing gastrostomy during the acquisition of P. aeruginosa colonization in gut. CONCLUSION: Gastrointestinal disorders, especially obstruction and surgical interventions, are also important for the acquisition of by P. aeruginosa, in the GI tract.