Infection withMycobacterium aviumComplex in Patients without Predisposing Conditions

Abstract

Pulmonary disease caused by Mycobacterium avium complex usually occurs in patients with chronic lung disease or deficient cellular immunity, and its prevalence is increasing. We describe 21 patients (mean age, 66 years) with such infection without the usual predisposing factors, representing 18 percent of the 119 patients surveyed. Seventeen women and 4 men were given a diagnosis of M. avium complex from 1978 to 1987, with a stable incidence over the decade, on the basis of pulmonary symptoms, abnormalities on chest films, positive cultures, and in 14, biopsy evidence of invasive disease. Most of the patients (86 percent) presented with persistent cough and purulent sputum, usually without fever or weight loss. The cough was present for a mean of 25 weeks before the correct diagnosis was made. Radiographic patterns of slowly progressive nodular opacities predominated (71 percent); only five patients had cavitary disease at presentation. All patients responded initially to antimycobacterial therapy, but eight eventually relapsed when it was stopped. Four patients died of progressive pulmonary infection caused by M. avium complex. The extent of the initial pulmonary involvement was greater in patients with progressive disease than in those whose condition improved. We conclude that pulmonary disease caused by the M. avium complex can affect persons without predisposing conditions, particularly elderly women, and that recognition of this disease is often delayed because of its indolent nature.

Rare case of Mycobacterium nebraskense presenting as asymptomatic cavitary lung lesion

“…The disease resembles typical tuberculosis clinically and radiographically, with cough, weight loss, upper lobe infiltrates, and cavities [5,6]. The second form presents as nodular bronchiectasis in immunocompetent adults without known underlying lung disease, usually nonsmoking slender women who have some skeletal deformities [7,8]. The third form presents as hypersensitivity pneumonitis after use of hot tubs and medicinal baths [9].…”

Pulmonary disease caused by nontuberculous mycobacteria

“…For example, for several decades older white nonsmoking women without clearly predisposing conditions have been noted to be disproportionately affected by PNTM [53]. Some potential explanation for this observation was recently offered by a study involving a referral cohort of mostly (i.e., 95%) older women, with PNTM and a phenotype consisting of a tall and lean body habitus, a high prevalence of scoliosis, mitral valve prolapse and pectus excavatum suggesting fibrillin abnormalities as a predisposing factor.…”

Epidemiology and Clinical Significance of Nontuberculous Mycobacteria in Patients Negative for Human Immunodeficiency Virus in Switzerland

“…Seven of these patients were considered immunocompetent, and one patient was receiving immunosuppressive therapy for the treatment of non-Hodgkin's lymphoma. Increasing numbers ofpulmonary disease due to MAC in immunocompetent patients have been reported [39,72]. Predisposing medical conditions observed in these patients were chronic pulmonary diseases such as COPD, bronchiectasis, previous tuberculosis, pneumoconiosis, or bronchogenic carcinoma [13].…”