Mycobacterium xenopi: innocent bystander or emerging pathogen?

Mycobacterium xenopi is a recognized cause of smoldering pulmonary disease in patients with chronic lung disease. This organism is frequently isolated from respiratory specimens from individuals infected with human immunodeficiency virus (HIV) and is often considered nonpathogenic. Cases of pulmonary and disseminated M. xenopi disease have been described in patients with HIV infection and other immunodeficiencies. Many physicians are unaware of the clinical significance of M. xenopi isolation. Whether this organism represents a commensal or a pathogen capable of causing considerable morbidity and mortality is not fully understood. In this study, we investigated the clinical significance of M. xenopi isolation and explored the clinical spectrum of M. xenopi disease. Clinical illness occurred both in elderly people with chronic lung disease and in young individuals with HIV infection. The repeated isolation of M. xenopi in association with pulmonary lesions suggests significant infection and mandates further workup and therapy.

Tropical pulmonary eosinophilia masquerading as acute bronchial asthma.

With the influx of immigrants from developing countries, deployment of American troops on foreign soil, and wide-ranging travel patterns of some United States citizens, one should expect an increase in the frequency of parasitic pulmonary diseases. We report a case of tropical pulmonary eosinophilia in a recent immigrant to Upstate New York from India. Tropical pulmonary eosinophilia is unfamiliar to most physicians practicing in North America, but should be included in the differential diagnosis of asthmatic bronchitis with hypereosinophilia when there is a history of recent travel to or residence in endemic areas. Furthermore, knowledge of this entity should also help in the differential diagnosis of other hypereosinophilic syndromes.

Mycobacterium xenopi infection masquerading as pulmonary tuberculosis in two patients infected with the human immunodeficiency virus.

Mycobacterium xenopi infections have rarely been reported among patients infected with the human immunodeficiency virus (HIV). We recently treated two HIV-infected men, neither of whom had a history of pulmonary disease or AIDS-defining conditions, and who had M. xenopi lung infections. Both patients presented with night sweats, cough, and pleuritic chest pain. Chest radiographs showed an upper-lobe nodule in the first patient and a perihilar cavitary infiltrate in the second patient. Both patients were initially believed to have pulmonary tuberculosis and were treated accordingly; however, only M. xenopi grew on cultures of multiple respiratory specimens. This diagnosis was confirmed by cultures of biopsied lung tissue from the first patient and of fluid from a peritracheal abscess in the second patient. Both patients' clinical conditions improved after multidrug therapy (isoniazid, rifampin, pyrazinamide, ethambutol, and ciprofloxacin in the first case; isoniazid, rifampin, and pyrazinamide in the second case). The second patient's condition improved despite in vitro resistance of his isolate to isoniazid and rifampin.

Pleural effusion in yellow nail syndrome: chemical pleurodesis and its outcome.

Two cases of yellow nail syndrome (a triad of yellow dystrophic nails, chronic lymphedema and pleural effusion) are described which demonstrate long-term control of recurrent pleural effusions by tetracycline pleurodesis. Neither patient developed problems as a result of the procedure enabling us to conclude that tetracycline pleurodesis is effective in managing reaccumulating pleural fluid in yellow nail syndrome and may avoid loss of lung function due to pleural peel.

Simultaneous legionellosis and invasive aspergillosis in an immunocompetent patient newly treated with corticosteroids.

Invasive pulmonary aspergillosis (IPA), although unusual, has been recognized in the immunocompetent host. Several cases of IPA with rapidly progressive respiratory failure have been reported in patients receiving short-term corticosteroid therapy for chronic obstructive pulmonary disease. Atypical pneumonia caused by dual infection with Legionella pneumophila and Mycoplasma pneumoniae has also been reported. We report an unusual case of simultaneous L pneumophila pneumonia and IPA in an asthma patient with suspected allergic bronchopulmonary aspergillosis newly treated with corticosteroids.