Treatment of disease caused by nontuberculous mycobacteria.

Tuberculosis has declined in incidence over the past several decades, but disease due to nontuberculous mycobacteria has not. Although mycobacteria other than tuberculosis are commonly isolated in medical laboratories, isolation of such organisms does not necessarily imply disease. Generalizations concerning diagnoses and therapy of nontuberculous mycobacterial diseases are not possible because the various organisms differ greatly in ability to produce disease and response to therapy.

Results of bronchoscopically obtained lower airway cultures from adult sickle cell disease patients with the acute chest syndrome.

PURPOSE: The purpose of this study was to determine the frequency of bacterial pneumonia as a cause of the acute chest syndrome in adult patients with sickle cell disease based on bronchoscopically obtained lower airway cultures and to describe the clinical, laboratory, and roentgenographic features of the acute chest syndrome in a series composed entirely of adult patients with sickle cell disease. PATIENTS AND METHODS: We reviewed the hospital records from 19 episodes (18 patients) of acute chest syndrome in adult patients with sickle cell disease (greater than or equal to 19 years of age) who had undergone flexible bronchoscopy to obtain lower airway cultures between January 1979 and July 1987. We also recorded patients' clinical, laboratory, and roentgenographic characteristics. RESULTS: Pneumonia was diagnosed in four of 19 episodes (21%) of acute chest syndrome based on quantitative cultures obtained at bronchoscopy. The pneumonia was caused by Streptococcus pneumoniae in two patients and mixed aerobic and anaerobic organisms in the other two patients. Forty-four of 45 blood cultures were negative, and one grew Staphylococcus epidermidis, which was considered a contaminant. Chest roentgenograms revealed lower lobe involvement in 17 episodes (90%) and bilateral infiltrates in six (32%). Pleural effusions occurred in seven episodes (37%), and pleural fluid samples obtained from five of these revealed sterile exudates. CONCLUSION: The results of this retrospective study suggest that bacterial pneumonia is an uncommon cause of acute chest syndrome in adult patients with sickle cell disease. These results are consistent with previous retrospective studies using noninvasive techniques to diagnose pneumonia. Nevertheless, there appeared to be no reliable noninvasive variables that could accurately differentiate between patients with and without pneumonia and, consequently, we recommend empiric antibiotic therapy in addition to usual supportive care of these patients.

Severe obstructive lung disease after smoke inhalation.

A 26-year-old-man developed severe obstructive lung disease after inhalation of smoke from a house fire. Bronchography demonstrated changes characteristic of bronchiolitis. Despite intensive therapy with bronchodilators and corticosteroids, he continues to have severe obstructive lung disease nine months after the smoke inhalation.

Tuberculous pleural effusion. Twenty-year experience.

We reviewed the records of 1,738 cases of tuberculosis seen during the period from 1968 to 1988 in Mobile, Alabama. Seventy cases of tuberculous pleural effusion were identified and constituted 4.9 percent of all disease due to Mycobacterium tuberculosis during this period. Tuberculous pleural effusion was diagnosed if the patient had M tuberculosis cultured from sputum, pleura, or pleural fluid and had a roentgenographic pleural effusion without an alternative explanation for the presence of the effusion. The diagnosis of tuberculous pleural effusion was made in the absence of a positive culture if the patient had an undiagnosed lymphocytic exudative pleural effusion and all clinical and roentgenographic abnormalities resolved on antimycobacterial chemotherapy. The mean age of all patients was 47 +/- 18.4 years. The 70 cases were evenly divided between 35 that were accompanied by roentgenographic pulmonary parenchymal infiltrates and 35 that occurred in the absence of parenchymal infiltrates. We conclude that cultures of all potentially diagnostic specimens (sputum, pleural fluid, and pleura) and an intermediate-strength skin test, are sensitive tests for the diagnosis of tuberculous pleural effusion. In addition, the age of patients with tuberculous pleural effusion appears to be increasing.

Use of a bronchoscopic protected catheter brush for the diagnosis of pulmonary infections.

Fiberoptic bronchoscopy using a protected brush catheter was done in 65 patients with suspected pulmonary infections to obtain uncontaminated specimens for culture. Quantitative aerobic and anaerobic cultures were done on each specimen. Forty-one patients had pneumonia. Ten bacteremic patients had the same organisms recovered from the catheter and blood cultures. Seven patients had received antibiotics before the procedure, and cultures grew no organisms in high concentration. In 23 of 24 remaining patients probable pathogens were recovered in high concentrations, and specific therapy resulted in clinical improvement in all of these patients. Five patients with lung abscesses and seven with necrotizing pneumonia had mixed aerobic and anaerobic organisms recovered. Twelve patients had final diagnoses of nonbacterial lung disease, and cultures were negative or revealed low concentrations of organisms. Quantitative cultures were necessary in distinguishing pathogens from nonpathogens. There were no complications. The results of this study indicate that fiberoptic bronchoscopy using a special protected catheter is an accurate and safe technique for identification of etiologic agents in lower respiratory tract infections.

Bronchoscopic protected specimen brush and bronchoalveolar lavage in the diagnosis of bacterial pneumonia.

Despite marked improvements in antibiotic therapy, the accurate diagnosis and treatment of bacterial lower respiratory tract infection remain a challenge. The bronchoscopic protected specimen brush and bronchoscopic bronchoalveolar lavage combined with quantitative bacterial cultures can provide sensitive and relatively specific information about lower airway flora. Both of these methods require strict observance of the required protocol, careful processing of the obtained specimens, and the absence of prior antibiotic therapy to obtain best results. These procedures are also of some utility in sickle cell acute chest syndrome, bronchiectasis, and in the immunocompromised host.

Use of a bronchoscopic protected catheter technique in the clinical evaluation of a new antibiotic.

We prospectively compared the usefulness of a bronchoscopic protected catheter technique with the results from sputum cultures in the evaluation of moxalactam, a new beta-lactam antibiotic. The significance of a given isolate on protected catheter culture was determined by quantitative bacteriology. 32 patients with community-acquired pneumonia were enrolled in the study and 31 grew common lower respiratory tract pathogens from their protected catheter specimen. The most common single pathogens recovered were Streptococcus pneumoniae (11 patients) and Haemophilus influenzae (2). Mixed flora, predominantly anaerobes, were isolated from 15 patients, and 3 patients had mixed aerobic infections. All seven bacteremic cases had the identical organism isolated from the protected catheter specimen, confirming the accuracy of the technique. Comparisons with sputum cultures showed that the predominant organism on sputum culture was the same as that obtained from the protected catheter culture in only 13% of the cases. Sputum cultures revealed either no pathogen or a different pathogen in 23 cases, and no sputum could be obtained in 4. Compared to cultures of expectorated sputum, we found the protected catheter bronchoscopic culture technique to have the following advantages in the bacteriologic evaluation of moxalactam: 1) greater accuracy and sensitivity in bacteremic patients; 2) accurate delineation of the bacteriology of infections; and 3) a higher percentage of patients with evaluable bacteriology leading to greater efficiency during the investigation.

The treatment of tuberculosis.

Short-course chemotherapy has made the treatment of TB easier and better than ever, but it works only when patients take the drugs regularly. Compliance is a must for therapy to be successful. Physicians treating patients with tuberculosis should be acutely aware of noncompliance, and every effort to ensure adequate treatment must be put forth. Directly supervised therapy is an excellent option when enough resources are available. Intermittent regimens markedly reduce the manpower required for observed therapy. New agents are being tested for in vitro activity against M. tuberculosis, and clinical studies of those found to be potentially effective are needed to formulate new regimens against the ever-increasing threat of multidrug-resistant TB.

Nosocomial pneumonia: trying to make sense of the literature.

Nosocomial pneumonia is hard to diagnose with any certainty. Widely accepted concepts regarding the infection are based on data that are far from conclusive. Published recommendations for diagnosis and treatment often reflect a concentrated effort to consolidate these data. According to the authors of this article, initial empirical treatment may be defined by dividing patients into specific host groups. However, this approach should always be supplemented by earnest attempts at identifying the cause with microbial cultures.

Tuberculosis in the 1990s.

The steady decline in tuberculosis case rate reversed in the mid-1980s, and tuberculosis cases have increased dramatically since that time. Important factors contributing to this increase are the human immunodeficiency virus (HIV) epidemic and tuberculosis occurring in foreign-born persons. Tuberculosis outbreaks have occurred in HIV clinics and wards, prisons, homeless shelters, nursing homes, and health care facilities. Some of the outbreaks have involved strains of tuberculosis resistant to multiple antituberculosis drugs. Recent recommendations for initial therapy of tuberculosis include the use of four drugs and directly observed therapy in an effort to prevent the emergence of further drug resistance.

Effect of a publicly funded tuberculosis service on the diagnosis of tuberculosis at a teaching hospital.

The speed and accuracy of diagnosis of tuberculosis on general medical teaching services were retrospectively compared to that on a designated publicly funded tuberculosis service and to recent discouraging reports in the literature. The diagnosis was confirmed in all patients on the designated service and in 78.8% of patients not on the designated service within one week. No patient was discharged undiagnosed. Acid-fast smears done by the hospital laboratory showed a sensitivity of 82.5% and a specificity of 98.4%. Radiologic reports indicated the presence of tuberculosis or cavities in 85% of chest x-ray films in patients with pulmonary disease. These results may indicate that a publicly funded tuberculosis service, by providing emphasis on tuberculosis, allows more rapid and accurate diagnosis of tuberculosis in all patients. The impact of such training on future health care delivery should be recognized when decisions regarding allocation of public funds are made.

Ketoacidosis.

The pathogenesis and treatment of diabetic ketoacidosis has been discussed. Insulin deficiency leads to increased rates of hepatic ketogenesis and gluconeogenesis with resultant hyperglycemia and ketonemia. Treatment consists of insulin and fluid replacement. Insulin therapy is titrated against the change in blood glucose concentration. Isotonic saline is the initial replacement fluid, and potassium is administered as required. Bicarbonate is employed in extreme acidosis, but its administration may contribute to the development of hypokalemia, CSF acidosis, and tissue hypoxia. It is hoped that a better understanding of the biochemical basis of ketoacidosis will permit the physician to develop a rational therapeutic regimen which will decrease the mortality associated with this condition.

Quantitative bacterial cultures of bronchoalveolar lavage fluids and protected brush catheter specimens from normal subjects.

Bronchoalveolar lavage (BAL) is quite useful in the diagnosis of nonbacterial lung infections, especially in immunocompromised patients, and recent studies have suggested that BAL may be useful in the diagnosis of bacterial pneumonia as well. Because previous studies indicated that bronchoscopic aspirates are usually contaminated by oropharyngeal flora, we anticipated that BAL fluid would also likely be contaminated. Therefore, the purpose of this study was to perform quantitative bacterial cultures on BAL fluids obtained from eight normal subjects. Prior to each procedure, saline was aspirated through the bronchoscope and submitted for culture. A protected brush catheter (PBC) specimen was obtained from each subject's right middle lobe, and then a BAL specimen was obtained from the same location. All specimens were quantitatively cultured for aerobic and anaerobic organisms. In addition, lidocaine concentrations were measured in the BAL fluids and the PBC specimens. Six of the eight bronchoscope cultures were sterile. Seven of the eight PBC specimens were sterile and one yielded less than 10(3) cfu/ml of normal oropharyngeal flora. One BAL fluid specimen was sterile and seven yielded from one to four bacterial strains each; however, quantitation revealed less than 10(4) cfu/ml in all specimens. Lidocaine concentrations (mean +/- 1 SD) were as follows: PBC specimen, 0.81 microgram/ml (+/- 0.62); BAL fluid specimen, 62.6 micrograms/ml (+/- 43). We conclude that BAL fluid obtained from normal subjects is frequently contaminated by oropharyngeal bacterial flora.(ABSTRACT TRUNCATED AT 250 WORDS)

Physiologic effects and serum lidocaine concentrations after inhalation of lidocaine from a compressed gas-powered jet nebulizer.

The physiologic effects, efficacy, and serum lidocaine concentrations were determined in 10 normal volunteers who inhaled nebulized lidocaine from a compressed gas-powered jet nebulizer. Physiologic variables and serial venous serum lidocaine concentrations were measured during and after lidocaine inhalation. All 10 subjects experienced loss of the gag reflex, which returned to normal at 32 +/- 5.9 min (mean +/- 1 SD), with a range of 20 to 40 min. There were no significant changes in systolic or diastolic blood pressures or heart rates. There were no significant changes from baseline in any of the measured spirometric variables (FVC, FEV1, peak expiratory flow rate, peak inspiratory flow rate). The peak mean serum lidocaine concentration measured at 20 min after beginning lidocaine inhalation was 0.52 microgram/ml, and the highest single value measured was 1.05 micrograms/ml. We conclude that inhalation of lidocaine from a compressed gas-powered jet nebulizer can produce safe and effective oropharyngeal anesthesia with minimal drug absorption.

Choosing an appropriate cutting point for conversion in annual tuberculin skin testing.

A previous report from our institution showed that the use of a two-step tuberculin testing program in new employees reduced the apparent rate of conversion in annual skin testing by eliminating the effect of the booster phenomenon. However, the converter rate subsequently remained too high. We propose that the use of 10 mm of induration as the cutting point gave a high rate of false conversion in our area of high prevalence of sensitivity to nontuberculous mycobacteria. A change to 15 mm of duration as the cutting point reduced our conversion rate from 2.6 to 1.2%, identified a group who demonstrated continued large tuberculin reactions at repeat testing, and eliminated age dependency from our converter population. We propose the choice of 15 mm of induration as the appropriate cutting point in annual employee tuberculin skin testing programs in areas in which sensitivity to nontuberculous mycobacteria is common.

The role of bacterial super infection in extensive pulmonary tuberculosis. Data from protected brush cultures in untreated patients from the University of South Alabama Medical Center, Mobile, Alabama, USA.

Pulmonary tuberculosis (TB) and bacterial pneumonia are both characterized by fever, cough, and purulent sputum production. Although TB alone can cause these symptoms, the possibility of a concomitant bacterial pneumonia has led some clinicians to treat these patients empirically with antibacterial agents. Neither the benefit of such empiric antibiotic therapy nor transtracheal aspirate cultures from patients with pulmonary TB have yielded consistent results. Consequently, we performed a prospective study to obtain lower airway secretions via a bronchoscopic protected specimen brush (PSB) technique for quantitative aerobic and anaerobic cultures from untreated patients with extensive pulmonary TB (defined as cavitary disease or involvement of > or = 3 segments). We obtained bronchoscopic samples from 3 untreated men aged 21, 61, and 60 years with extensive pulmonary TB. There was no significant bacterial growth (aerobic or anaerobic) from the specimens obtained. These results, therefore, do not support the hypothesis that bacterial pneumonia is a common concomitant of extensive pulmonary TB.