No 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.

No abstract

Inhaled beta-adrenergic agonists are the most commonly used medications for the treatment of asthma although there is evidence that regular use may produce adverse effects in some patients. Polymorphisms of the beta(2)-adrenergic receptor (beta(2)-AR) can affect regulation of the receptor. Smaller studies examining the effects of such polymorphisms on the response to beta-agonist therapy have produced inconsistent results. We examined whether polymorphisms at codon 16 (beta(2)-AR-16) and codon 27 (beta(2)-AR-27) of the beta(2)-AR might affect the response to regular versus as-needed use of albuterol by genotyping the 190 asthmatics who had participated in a trial examining the effects of regular versus as needed albuterol use. During the 16-wk treatment period there was a small decline in morning peak expiratory flow in patients homozygous for arginine at B(2)-AR-16 (Arg/Arg) who used albuterol regularly. This effect was magnified during a 4-wk run out period, during which all patients returned to using as-needed albuterol, so that by the end of the study Arg Arg patients who had regularly used albuterol had a morning peak expiratory flow 30. 5 +/- 12.1 L/min lower (p = 0.012) than Arg/Arg patients who had used albuterol on an as needed basis. There was no decline in peak flow with regular use of albuterol in patients who were homozygous for glycine at beta(2)-AR-16. Evening peak expiratory flow also declined in the Arg/Arg patients who used albuterol regularly but not in those who used albuterol on an as-needed basis. No significant differences in outcomes between regular and as-needed treatment were associated with polymorphisms at position 27 of the beta(2)-AR. No other differences in asthma outcomes that we investigated occurred in relation to these beta(2)-AR polymorphisms. Polymorphisms of the beta(2)-AR may influence airway responses to regular inhaled beta-agonist treatment.