The effect of smoking on tuberculosis: different patterns and poorer outcomes.

SETTING: It has been well documented that smoking increases the risk of tuberculosis (TB). However, few studies have evaluated the impact of smoking on TB. We conducted this retrospective study to evaluate the influences of smoking on the manifestation and outcome of TB. DESIGN: All culture-confirmed TB patients from July 2002 to December 2003 were identified and their medical records reviewed. RESULTS: A total of 523 TB patients, including 207 (39.6%) who had ever smoked, were studied. The ever-smokers were significantly older, more likely to have underlying diseases and a duration of symptoms > 60 days, and less likely to have extra-pulmonary involvement and have completed treatment (64.7% vs. 78.5%). Radiographically, more ever-smokers with pulmonary tuberculosis (PTB) presented with miliary lesions, multiple nodules or masses, upper lung predominance and cavitation than never-smokers. Although smoking was associated with poor prognosis on univariate survival analysis, multivariate analysis revealed that independent poor prognostic factors included age, underlying disease, symptom duration < or = 60 days, extra-pulmonary involvement, serum albumin level < 3.5 g/dl and delayed treatment. CONCLUSIONS: Our results demonstrate that smoking is significantly associated with radiographic manifestations of PTB, but not with death among PTB patients.

Recognising tuberculosis in the lower lung field: an age- and sex-matched controlled study.

OBJECTIVE: Tuberculosis (TB) can sometimes present with consolidation in the lower lung field. This study was conducted to compare the manifestations of lower-lung-field TB (LLFTB) and other pulmonary TB. DESIGN: All new culture-proven TB patients with lower-lung-field consolidation from July 2001 through December 2002 were included. Age- and sex-matched TB patients with upper lung involvement were selected as controls. RESULTS: A total of 79 patients with LLFTB were included. Their mean age was 58.8 years; 46 were male. The clinical, radiographic and laboratory findings were similar in the LLFTB and the control groups, except that the LLFTB patients had less cavitation (P = 0.005). Patients with LLFTB were diagnosed (P = 0.051) and treated (P = 0.001) later than the control patients. The calibres of the trachea and both main bronchi were significantly smaller in the LLFTB group (P < 0.001). More patients with LLFTB developed segmental or lobar atelectasis during follow-up (P = 0.028). CONCLUSIONS: The manifestations of LLFTB are non-specific. The lower-lung involvement, the lower incidence of cavitation and the higher probability of segmental or lobar atelectasis implied that LLFTB was primary TB. A small bronchial calibre probably contributed to its development.

Mechanism of repression of squamous differentiation marker, SPRR1B, in malignant bronchial epithelial cells: role of critical TRE-sites and its transacting factors.

The overexpression of SPRR1B in bronchial epithelium is a marker for early metaplastic changes and the loss of its expression is associated with an irreversible malignant transformation. In the present study, we have used a model system consisting of normal and malignant bronchial epithelial (BE) cells to elucidate the differential transcriptional control of SPRR1B. SPRR1B expression is either detectable or PMA (phorbol 13-myristate 12-acetate) -inducible in several malignant BE cells including squamous, adeno, small and large cell carcinomas. Loss of SPRR1B expression is correlated well with the lack of strong in vivo protein-DNA interactions at the -152 bp promoter, which contains two functional TRE sites. Even though the basal level AP-1 protein DNA binding pattern is different between normal and malignant cells, PMA significantly enhances Jun and Fos binding to the consensus TRE site in both cell types. Intriguingly, the composition of AP-1 protein binding to the -152 to -86 bp SPRR1B promoter is quite different. In untreated cells, SPRR1B promoter is predominantly occupied by JunD and Fra2. PMA significantly induced binding of JunB and Fra1 in normal cells, while JunB and Fra2 bound to TREs in the malignant cells. Overexpression of fra1 in malignant cells significantly enhanced SPRR1B promoter activity. In contrast, overexpression of fra2, but not fra1, strongly reduced both basal and PMA-inducible promoter activities in normal cells. Together, these results indicate that either temporal expression and/or differential activation of AP-1 proteins, especially Fra1 and Fra2, might contribute to the dysregulation of terminal differentiation marker, SPRR1B, expression in various BE cells.

A 10-year experience with bacteriology of acute thoracic empyema: emphasis on Klebsiella pneumoniae in patients with diabetes mellitus.

STUDY OBJECTIVES: To provide an updated evaluation of the bacteriology of acute thoracic empyema for more efficacious treatment. DESIGN: : The medical and microbiological records of all patients who received a diagnosis of acute thoracic empyema were reviewed. Based on the bacteria isolated from the pleural fluid, the patients were classified into the following four groups: aerobic or facultative Gram-positive; aerobic Gram-negative; anaerobic; and mixed. SETTING: A university-affiliated tertiary medical center. PATIENTS AND METHODS: From January 1989 to December 1998, 171 patients with a diagnosis of acute thoracic empyema were treated. A comparative analysis of the isolates from pleural effusions, the mean length of hospital stay, the mean duration of chest tube drainage, the mean duration between the onset of symptoms and the establishment of diagnosis, treatment efficacy, and the need for subsequent intervention was performed. RESULTS: A total of 163 microorganisms were isolated from the pleural fluid of 139 patients. These patients were classified according to the following types of isolates: aerobic or facultative Gram-positive (n = 47); aerobic Gram-negative (n = 59); anaerobic (n = 14); and mixed (n = 19). Klebsiella pneumoniae was the most commonly isolated pathogen (24. 4%) and was strongly associated with a diagnosis of diabetes mellitus. The mortality rate of patients with aerobic Gram-negative bacilli isolated was the highest (22.0%), followed by those with mixed pathogens isolated (15.7%), aerobic or facultative Gram-positive (6.4%), and anaerobic (0%). CONCLUSIONS: The increasing incidence of acute thoracic empyema caused by Gram-negative bacilli, especially by K pneumoniae, has become an increasing problem. The isolation of aerobic Gram-negative bacilli or multiple pathogens from pleural fluid is associated with a poor prognosis and indicates a need for more aggressive antimicrobial chemotherapy.

Ultrasonography and color Doppler imaging of metastatic pulmonary choriocarcinoma.

Chest ultrasound and color Doppler flow imaging were used to assess the pulmonary nodule of a 24-year-old pregnant woman with dyspnea and hemoptysis. The ultrasonogram showed multiple hypoechoic subpleural nodules. Color Doppler imaging of the nodules revealed characteristics of high vascularity and high blood flow. A percutaneous needle aspiration under ultrasonic guidance confirmed the diagnosis of choriocarcinoma.

Mucosa-associated lymphoid tissue lymphoma of the lung with cold-reacting autoantibody-mediated hemolytic anemia.

Mucosa-associated lymphoid tissue lymphoma (MALT-oma) of the lung is a rare low-grade B cell lymphoma arising from bronchus-associated lymphoid tissue. This report concerns a 39-year-old woman with bilateral diffuse alveolar consolidations and cold-reacting autoantibody-mediated hemolytic anemia. Open-lung biopsy showed angulated lymphoid cells with lymphoepithelial lesions. Immunocytochemistry revealed that the lymphoid cells were positive for CD19, CD20, and IgM (lambda), which was consistent with immunophenotype of MALToma. The serum immunoelectrophoresis demonstrated IgM (lambda) monoclonal gammopathy. The association of cold-reacting auto-antibody-mediated hemolytic anemia with MALToma, to our knowledge, has never been reported before in the English language.

Clinical spectrum of tuberculosis in older patients.

OBJECTIVE: To investigate the clinical differences between old and young patients infected with Mycobacterium tuberculosis in a developing country. DESIGN: Retrospective chart and chest radiograph review. SETTING: A university-affiliated teaching hospital. PATIENTS: The medical records of patients with documented tuberculosis (TB) from January 1990 through December 1991 were analyzed. Clinical assessment included sex, age, diagnosis at first visit, past history, symptoms and signs, laboratory data, X-ray findings, bacteriological examinations, outcome, time elapsed from first visit to initiation of anti-TB therapy and the major determinants for starting anti-TB therapy. Statistical significances were analyzed by Student's t test and chi 2 tests. RESULTS: Among 205 patients with culture-proven TB, 57 were 65 years of age and older (range, 65 to 91; mean, 73) and 148 under 65 years of age (range, 16 to 64; mean, 41). There was a higher incidence of previous TB (26.3% vs. 16.2%) and diabetes mellitus (24.5% vs. 14.3%) in the elderly patients. Initial diagnosis of TB at first visit was less frequent in the elderly than in the young group (38.6% vs. 47.3%), although symptoms and signs at first visit were similar in each of the age groups. Radiographic presentation with mass lesions was more frequently encountered in elderly patients (10.5% vs. 2.1%, P < .05). Elapsed time from the first visit to suspicion of TB and the initiation of anti-TB therapy was frequently delayed in elderly patients (22 +/- 23 vs. 13 +/- 20 days, P < .05). The incidence of drug-resistance (39% vs. 16%, P < .05) and unfavorable response to anti-TB therapy (17.5% vs. 3.4%, P < .05) were significantly higher in the older patients. CONCLUSIONS: Although clinical presentation of TB in the elderly did not differ significantly from that in younger patients, this study showed that diagnosis and treatment were more often delayed in the elderly, and there was a higher incidence of treatment failure.

Variations in the NRAMP1 gene and susceptibility of tuberculosis in Taiwanese.

SETTING: National Taiwan University Hospital, Taipei, Taiwan. OBJECTIVE: To study the variations in the NRAMP1 gene using five genotypes (274C/T, 577-18G/A, A318V, D543N and 3' untranslated region [UTR]), and the susceptibility of tuberculosis and HIV infection in Taiwanese. DESIGN: The study sample included 49 patients with tuberculosis, 48 healthy control subjects and 60 HIV-infected patients. The polymerase chain reaction (PCR) products amplified from their genomic DNA were subjected to restriction enzyme digestion and were analysed using agarose gel electrophoresis. RESULTS: A318V was not polymorphic in the studied population. Only D543N and 3'UTR were more heterozygous. In 274 C/T and 577-18G/A, the allele frequencies showed the predominant type to be the homozygous patterns C/C (94%) and G/G (94%), respectively. There were no statistically significant differences between the tuberculosis patients and the healthy control subjects. Despite the high susceptibility to Mycobacterium tuberculosis in HIV-infected patients, genotypic frequencies in the HIV-positive patients were not significantly different between tuberculous (n = 29) and non-tuberculous patients (n = 31). In comparison with previous studies, there were significant differences between different ethnic groups in allele frequencies for 274C/T, D543N and 3'UTR. CONCLUSION: The allele and genotype of NRAMPI polymorphism among Taiwanese differed from those of Caucasians, Africans and Hispanics. No allelic associations were identified between the NRAMP1 alleles and tuberculosis susceptibility.

Expression of integrins in human cultured mesothelial cells: the roles in cell-to-extracellular matrix adhesion and inhibition by RGD-containing peptide.

Integrins play key roles in cell-to-cell and cell-to-extracellular matrix (ECM) adhesion. We investigated integrin expression on pleural mesothelial cells (PMCs) and the inhibitory effect of arginine-glycine-asparate (RGD)-containing peptide on the adhesion of PMCs to fibronectin and collagen. Using flow cytometry and immunostaining, PMCs freshly isolated from pleural effusions and one mesothelial cell line were screened for different integrins. Intact pleural tissue was evaluated by immunohistochemistry. The adhesion of Met-5A cells to fibronectin and collagen types I, III and IV was assayed with prior treatment of various concentrations of glycine-arginine-glycine aspartate-serine (GRGDS). On primary PMCs, alpha2, alpha3, alpha5, beta1, beta3 and alphavbeta3 were highly expressed (>70%); alpha1 expression was intermediate (30-70%); and alpha4 and alpha6 expressions were low (< 30%). On Met-SA cells, alpha3, alpha5, alpha6 and beta1 were highly expressed (>70%); alpha1 was intermediate (30-70%); and alpha2, alpha4, beta3 and alphavbeta3 were low (<30%). The patterns of immunostaining on pleural tissues were similar to the results of flow cytometry for primary PMCs except for beta3. There was no statistically different expression in various disease states (transudate vs. exudate, benign vs. malignant). The inhibitory effect of GRGDS peptide on Met-5A cell adhesion to all four matrix proteins was dose-dependent.

Comparison of inflammatory cytokine concentration and physiologic parameters in septic shock.

Cytokine-related systemic intravascular inflammation may represent a common pathogenic link between initial insult and multiple organ failure in septic shock patients. We conducted a prospective study with controls in the National Taiwan University Hospital intensive care unit to compare plasma levels of tumor necrosis factor alpha (TNF-alpha), interleukin 6 (IL-6), and circulating intercellular adhesion molecule 1 (cICAM-1) with clinical physiologic parameters in the outcome of patients with septic shock. Healthy volunteers (n = 37) and patients with septic shock admitted to the unit from January to December 1994 (n = 31) were enrolled. Clinical data, APACHE (Acute Physiology and Chronic Health Evaluation) III scores, multiple organ failure scores, the presence of acute respiratory distress syndrome, and outcome were evaluated. The plasma levels of TNF-alpha, IL-6, and cICAM-1 were measured using enzyme-linked immunosorbent assay. Subgroups of survivors and nonsurvivors were compared for plasma levels of these factors or days 1, 2, 3, 7, and 14 after diagnosis of septic shock. Of the patients with septic shock, 20 survived and 11 died. The initial plasma levels of IL-6 were significantly higher in nonsurvivors (p < 0.05). There was a significant inverse correlation between plasma IL-6 level and survival in the first week (r = 0.4297-0.7242, p < 0.05). APACHE III score (r = 0.4335, p = 0.015), acute respiratory distress syndrome (r = 0.5913, p < 0.001), and multiple organ failure score (r = 0.736, p < 0.001) were more strongly (negatively) correlated with survival than the concentrations of TNF-alpha and cICAM-1 by Spearman's rank sum test. Our results showed that in patients with septic shock, of the inflammatory cytokines, only IL-6 showed significantly higher plasma levels in the nonsurvivor group. Inflammatory cytokine levels were not more strongly correlated with the outcome of patients with septic shock than physiologic parameters.

Constrictive pericarditis in patients with tuberculous pericarditis.

Constrictive pericarditis is a complication of tuberculous pericarditis that necessitates surgical intervention. In this study, we sought to identify echocardiographic features that could predict the development of constrictive pericarditis from acute or subacute pericarditis. From January 1988 through May 1998, all patients with a discharge diagnosis of tuberculous pericarditis were enrolled in the study, and their clinical features, laboratory findings, sonographic images, treatments, and outcomes were analyzed. Tuberculous pericarditis was demonstrated on the basis of positive Mycobacterium tuberculosis cultures from pericardial fluid or tissue in 11 patients; pericardial biopsy specimens demonstrating caseating granulomas in seven; and bacteriologic or histologic evidence of active extra-pericardial tuberculosis in conjunction with major pericardial effusion in four. Seventeen patients had effusive tuberculous pericarditis and five had constrictive tuberculous pericarditis as the initial diagnosis. The echocardiographic findings of effusive pericarditis were classified as shaggy-type effusion (n = 8) and non-shaggy-type effusion (9). Shaggy effusion was defined as the presence of multiple fibrin strands or a mass-like exudate coating the pericardium and bridging the pericardial effusion. Non-shaggy effusion was characterized by an anechoic pericardial space with or without a thickened pericardium, but no shaggy exudative coating. The mean duration between the onset of symptoms and diagnosis was longer in patients with shaggy-type effusion (39.6 +/- 8.7 vs 21.0 +/- 13.9 days, p < 0.05). Prednisolone (20-30 mg/d) was used in addition to antituberculous chemotherapy in 11 of the 17 patients with effusive pericarditis. Two of 11 patients (18%) who received steroid therapy, and five of the six patients (83%) who did not, developed constrictive pericarditis in the following year. Therefore, we concluded that adjuvant therapy with steroids significantly decreased the risk of constrictive pericarditis in patients with non-shaggy, but not shaggy, effusion.

Diagnosis of pulmonary sequestration by magnetic resonance imaging.

Pulmonary sequestration, an uncommon congenital anomaly, is traditionally best diagnosed using arteriography; however, this is invasive and not without risk of morbidity and mortality. We report two patients with pulmonary sequestration diagnosed using magnetic imaging techniques. The first was a 22-year-old woman and the second a 17-year-old boy, both of whom presented with symptoms of cough and exertional dyspnea. Pulmonary sequestration was suspected from their chest radiographs. Magnetic resonance imaging and magnetic resonance angiography clearly demonstrated the aberrant artery arising from the aorta in a single noninvasive examination that did not require the use of contrast medium. We recommend magnetic resonance imaging as a safe, efficient, and noninvasive modality for the diagnosis of pulmonary sequestration.

Clinical spectrum of acute respiratory distress syndrome in a tertiary referral hospital: etiology, severity, clinical course, and hospital outcome.

BACKGROUND AND PURPOSE: The clinical picture of patients with acute respiratory distress syndrome (ARDS) in Taiwan has seldom been reported, although new definitions of ARDS have been introduced over the past years. The purpose of this study was to investigate the clinical characteristics, modalities of management, and outcomes in patients with ARDS treated in a tertiary referral hospital. METHODS: Case records were selected through a computerized search of diagnosis codified at discharge during the period from January 1995 to June 1997. Patients who met the criteria of the American-European Consensus Conference definition of ARDS were included and their medical records were retrospectively reviewed. RESULTS: A total of 145 patients (91 men, 54 women; mean age, 58 years) who fulfilled the criteria for ARDS were identified. Malignancy (n = 53) and diabetes mellitus (n = 23) were the most common co-morbid conditions. Pneumonia (n = 90), including community-acquired pneumonia in 45 (31%) patients, was the most common risk factor. The lung injury score at the time of ARDS diagnosis was 2.89 +/- 0.40 (mean +/- standard error, SE). The worst value of PaO2/FIO2 was 86.8 +/- 3.8 mm Hg (mean +/- SE). Among the 145 patients, 130 (90%) received mechanical ventilation and 118 (81%) were treated in the intensive care unit. In-hospital mortality was 87%. Seventy (48%) patients received intensive treatment for ARDS, among whom 52 (74%) died; the most common causes of death were multiple organ failure (54%) and respiratory failure (23%). CONCLUSIONS: The mortality in patients with ARDS was high in this tertiary referral institution. Our findings suggest that aggressive ventilatory, pharmacologic, and supportive therapy may be important to achieve a higher survival rate.

Nosocomial Exophiala jeanselmei pseudoinfection after sonography-guided aspiration of thoracic lesions.

BACKGROUND AND PURPOSE: During the period from August 1994 to October 1998, a total of 19 isolates of Exophiala jeanselmei were recovered from 17 patients with various underlying thoracic diseases treated at National Taiwan University Hospital. The purpose of this study was to describe the clinical characteristics of these patients and to determine the microbiologic relatedness of the E. jeanselmei. METHODS: Of the 19 isolates, 11 from nine patients were preserved and were identified based on their biotypes as determined by the API ID32C System, their cellular fatty acid profiles by gas-liquid chromatography, their antibiotypes to five antifungal agents by the E-test, and their random amplified polymorphic DNA (RAPD) patterns by arbitrarily primed PCR. Extensive environmental surveillance cultures and cultures from the skin of eight patients and hands of one physician were also performed. RESULTS: One of the 17 patients had E. jeanselmei isolated from cutaneous phaeohyphomycosis (3 isolates), and the other 16 patients had isolations from pleural effusion specimens (15 isolates) or lung mass (1 isolate) following sonography-guided aspiration. The latter 16 patients had no clinical or pathologic evidence of fungal infection. Isolates (clone 1) from aspirated specimens had identical biotypes, antibiotypes, and RAPD patterns, which were different from those of the three isolates (clone 2) from the patient with a cutaneous lesion. All specimens from environmental sources, patients' skin, and the hands of the physician were negative for E. jeanselmei. CONCLUSION: This series of patients demonstrates the difficulty in identifying the sources of a nosocomial pseudoinfection due to this slow-growing microorganism when isolated from pleural effusion specimens.

Empirical treatment with a fluoroquinolone delays the treatment for tuberculosis and is associated with a poor prognosis in endemic areas.

BACKGROUND: A study was conducted to evaluate the effect of the empirical use of fluoroquinolones on the timing of antituberculous treatment and the outcome of patients with tuberculosis in an endemic area. METHODS: All patients with culture confirmed tuberculosis aged > or =14 years diagnosed between July 2002 and December 2003 were included and their medical records were reviewed. RESULTS: Seventy nine (14.4%) of the 548 tuberculosis patients identified received a fluoroquinolone (FQ group), 218 received a non-fluoroquinolone antibiotic (AB group), and 251 received no antibiotics before antituberculous treatment. Fifty two (65.8%) experienced clinical improvement after fluoroquinolone use. In the FQ group the median interval from the initial visit to starting antituberculous treatment was longer than in the AB group and in those who received no antibiotics (41 v 16 v 7 days), and the prognosis was worse (hazard ratio 6.88 (95% CI 1.84 to 25.72)). More patients in the FQ and AB groups were aged >65 years (53.2% and 61.0% v 31.5%), had underlying disease (53.2% and 46.8% v 34.3%), and were hypoalbuminaemic (67.2% and 64.9% v 35.1%). Of the nine mycobacterial isolates obtained after fluoroquinolone use from nine patients whose initial isolates were susceptible to ofloxacin, one (11.1%) was resistant to ofloxacin (after fluoroquinolone use for 7 days). Independent factors for a poor prognosis included empirical fluoroquinolone use, age >65, underlying disease, hypoalbuminaemia, and lack of early antituberculous treatment. CONCLUSIONS: 14.4% of our patients with tuberculosis received a fluoroquinolone before the diagnosis. With a 34 day delay in antituberculous treatment and more frequent coexistence of underlying disease and hypoalbuminaemia, empirical fluoroquinolone treatment was associated with a poor outcome. Mycobacterium tuberculosis isolates could obtain ofloxacin resistance within 1 week.

Bronchoscopic and angiographic findings in tracheobronchial endometriosis.

The case is described of a 31 year old woman who presented with complaints of recurrent haemoptysis coinciding with menstruation. Bronchoscopic examination revealed multiple purplish-red submucosal lesions on the right side of the trachea and bilateral bronchial trees which appeared during her menses and regressed in the intermenstrual periods. Brush cytology revealed cell clusters consistent with endometrial origin. Bronchial angiography demonstrated prominent vasculature at the right paratracheal area and bilateral bronchial trees corresponding to the lesions seen on bronchoscopic examination. Her haemoptysis was satisfactorily controlled by danazol therapy and follow up bronchoscopy showed disappearance of the tracheobronchial lesions. To our knowledge this is the first case of thoracic endometriosis with tracheal involvement.

Sonographic septation: a useful prognostic indicator of acute thoracic empyema.

The aim of this study was to identify sonographic predictors of patient outcomes or need for surgical intervention of acute thoracic empyema. All patients with a clinical diagnosis of thoracic empyema underwent transthoracic ultrasonographic examination and thoracentesis at admission. According to the presence or absence of septa in sonographic images, the patients were classified into two groups: septated and nonseptated. Sonographic findings were analyzed with respect to duration of hospital stay, chest tube drainage, and treatment efficacy. A total of 163 consecutive patients were included in the study (83 patients with septated and 80 with nonseptated sonographic images). The mean duration of hospital stay (35.4 versus 27.0 days, P = 0.009) and chest tube drainage (13.1 versus 7.6 days, P < 0.001) for the patients with septa were significantly longer than for those without septa. The patients with septa were more likely to undergo intrapleural fibrinolytic therapy (63.8% versus 38.8%, odds ratio 2.79, P = 0.001) and surgical intervention (24.3% versus 7.5%, odds ratio 3.92, P = 0.004). We concluded that sonographic septation is a useful sign to predict the need for subsequent intrapleural fibrinolytic therapy and surgical intervention in cases of acute thoracic empyema. Early fibrinolytic therapy or even surgical intervention may be indicated in patients with sonographic septations.

Nodular amyloidosis of the lung and the breast mimicking breast carcinoma with pulmonary metastasis.

Nodular amyloidosis of the breast and lung is a rare condition of unknown aetiology. The disease runs a benign course, but offers a diagnostic problem due to nonspecific histological features. We describe the case of a 56 year old woman with a 5 year history of multiple nodules of both lungs and left breast, clinically mimicking breast carcinoma with pulmonary metastasis. To our knowledge, this is the first case of cytologically proven amyloidosis diagnosed by ultrasound-guided percutaneous transthoracic fine-needle aspiration of pulmonary nodules.

Bacteriology of infected cavitating lung tumor.

Differentiation between in situ infection and simple tumor necrosis in cavitating lung tumors by means of imaging studies is difficult. In this study, we prospectively investigated the role of ultrasound (US)-guided transthoracic aspiration for bacteriologic examination of infected cavitating lung tumors, and the influence of the culture results on the treatment of patients. Twenty-two patients (18 men and four women) with cavitating lung tumors treated from January 1996 to October 1998 were included. All patients underwent US-guided transthoracic aspiration for bacterial, fungal, and mycobacterial cultures. Microorganisms were isolated from six of seven febrile patients and one of 15 nonfebrile patients. A total of nine pathogens were isolated from seven patients: Klebsiella pneumoniae (n = 3); Haemophilus influenzae (n = 2); Enterococcus faecium (n = 1); Bifidobacterium (n = 1); Shewanella putrefaciens (n = 1); and Mycobacterium tuberculosis (n = 1). Two pathogens were isolated from the aspirate cultures in two patients, while the others had monomicrobial infection. The six febrile patients who had positive lung aspirate cultures were treated with empiric antimicrobial agents before the culture results were available, and the culture results led to adjustment of the antibiotic regimen in five of these. The clinical conditions of the six patients with infected cavitating lung tumors improved after the initiation of individualized antimicrobial treatment. Pneumothorax occurred in one patient, and was the sole procedure-related complication. In conclusion, US-guided transthoracic aspiration is helpful for differentiating infected cavitating lung tumors from simple tumor necrosis. Infection in cavitating lung tumors is common among febrile patients, and the culture results can guide modification of the antimicrobial therapy.