The prognostic significance of FDG-PET in advanced non-small cell lung cancer / 대한내과학회지

BACKGROUND/AIMS: Lung cancer is the leading cause of cancer-related death in Korea. Non-small cell lung cancer (NSCLC) comprises 80~85% of lung cancer. Positron emission tomography with [18F]fluorodeoxyglucose (FDG-PET) shows various levels of FDG uptake for patients with NSCLC. This study determined whether the standardized uptake value (SUV) of FDG uptake by PET is a prognostic factor for advanced NSCLC. METHODS: FDG-PET was performed in 59 patients with stage IIIb and IV NSCLC. The SUV was calculated for each patient. Overall survival (OS) and time to progression were calculated using the Kaplan-Meier method and evaluated with the log-rank test. The prognostic significance was assessed using univariate and multivariate analyses. RESULTS: A cutoff of 7 for the SUV gave the best criminative value. In the univariate analysis, performance status (p=0.02) and SUV (p=0.03) were significant predictors of OS. The patients with low SUVs (7, p=0.04). A multivariate Cox analysis identified performance status and the SUV as important for the prognosis. CONCLUSIONS:These results suggest that SUV is a significant prognostic factor in patients with advanced non-small cell lung cancer.

Improvement of Pulmonary Function after Administration of Azithromycin in a Patient with Bronchiolitis Obliterans: a Case Report / 결핵및호흡기질환

Bronchiolitis obliterans (BO) is a serious noninfectious complication following an allogeneic bone marrow transplant (BMT). A 21-year-old female received an allogeneic BMT as a treatment for myelodyplastic syndrome. Four months after the BMT, progressive dyspnea developed and BO was also diagnosed by a lung biopsy. The patient was administered steroid and immunosuppressive agents for 1 year but there was no improvement in pulmonary function. Azithromycin was prescribed (500 mg q.d. for 3 days followed by 250 mg three time a week) because macrolides might decrease the inflammatory reaction leading to BO. The patient's pulmonary function improved after administration of azithromycin for 1 year. The forced expiratory volume in a one second (FEV1) increase was 220 mL (28.2%) and the forced vital capacity (FVC) increase was 460 mL (25.7%). We report the improvement in the pulmonary function after the administration of azithromycin for 1 year in a patient with BO after a BMT.

The Clinical Characteristics and Prognosis of Elderly Patients with Lung Cancer Diagnosed in Daegu and Gyeongsangbukdo / 결핵및호흡기질환

BACKGROUND: Lung cancer is the leading cause of cancer death in South Korea since the year 2000 and it is more common in elderly patients, with a peak incidence at around 70~80 years of age. However, these elderly patients receive treatment less often than do the younger patients because of organ dysfunction related to their age and their comorbidities, and they show poor tolerance to chemotherapy. The aims of this study were to analyze the clinical characteristics and treatment-related survival of elderly patients with lung cancer. METHODS: In this retrospective study, we analyzed the clinical data of 706 lung cancer patients who were diagnosed at hospitals in Daegu and Gyeongsangbukdo from January 2005 to December 2005. We compared the clinical characteristics and outcomes of the patients who were aged 70 years and older (elderly patients) with those clinical characteristics and outcomes of the younger individuals. RESULTS: The median age of the patients was 68 years (from 29 to 93) and the elderly patients were 38.7% (n=273) of all the study's patients. Squamous cell carcinoma was the most common type of lung cancer in both the elderly and younger patient groups. Elderly patients had more symptoms of dyspnea and chronic obstructive pulmonary disease (COPD) than the younger patients (p<0.001 and p<0.001, respectively). A good performance status (ECOG 0-1) was less common for the elderly patients (p<0.001). The median survival of the non-small cell lung cancer (NSCLC) patients was significantly higher in the younger patient group than in the elderly patient group (962 days vs 298 days, respectively, p=0.001). However, the median survival of the NSCLC patients who received any treatment showed no significant difference between the younger patient group and the elderly patient group (1,109 days vs 708 days, respectively, p=0.14). CONCLUSION: Our data showed that appropriate treatment for selected elderly patients improved the survival of patients with NSCLC. Therefore, elderly NSCLC patients with a good performance status should be encouraged to receive appropriate treatment.

Efficacy of administration of weekly docetaxel combined with platinum as a first-line treatment for patients with advanced non-small cell lung cancer / 대한내과학회지

BACKGROUDN: Docetaxel is a highly effective chemotherapeutic agent with proven efficacy for non-small cell lung cancer (NSCLC). However, myelosuppression can be a substantial concern when docetaxel is administered every 3 weeks. Weekly administration of low-dose docetaxel has demonstrated a comparable efficacy together with a distinct toxicity profile with reduced myelosuppression. We conducted a phase II study of weekly administration of docetaxel and cisplatin or carboplatin in patients with advanced NSCLC to evaluate efficacy and safety. METHODS: Twenty-nine patients with advanced or metastatic NSCLC who had not received prior treatment were enrolled in the study. The patients received intravenous infusions of docetaxel (35 mg/m2 on days 1, 8, 15) and cisplatin (75 mg/m2 on day 1) or carboplatin (AUC 6), followed by a week of rest. RESULTS: Twenty-six patients were assessable for efficacy and all patients were assessable for toxicity determination. The overall response rate of the regimen was 44.8%. The median survival was 11.3 months, and the 1-year survival rate was 37%. Of the hematologic toxicities, grade 3/4 neutropenia were observed in 12.6% of the patients, but there were no episodes of neutropenic fever. Non-hematologic toxicities were mild. CONCLUSIONS: With this weekly dosing regimen, although efficacy is comparable, myelosuppression is substantially less, and the overall tolerability profile is better than with dosing every 3 weeks.

Paclitaxel for elderly patients with advanced NSCLC / 대한내과학회지

BACKGROUND: Combination chemotherapy including platinum is based on treatment of advanced non-small cell lung cancer (NSCLC). But combination chemotherapy is not tolerable in elderly patients. Paclitaxel is one of the most active single chemotherapeutic agent in advanced NSCLC. We evaluated the efficacy and safety of single paclitaxel chemotherapy in elderly with advanced NSCLC. METHODS: From September 2002 to May 2004, a total 24 patients aged 70 years and older with advanced NSCLC were enrolled in this study. Treatment was consisted with paclitaxel 135 mg/m2 intravenously for 3hrs on day 1. Chemotherapy repeated every three weeks until disease progression or severe toxicity developed. RESULTS: Of the 24 patents, only 18 patient can be evaluated and 4 partial remission, 11 stable diseases and 3 progressive diseases were observed. Based on an intent-to-treatment analysis, The overall response rate was 17%. The estimated median survival and median time to progression were 44 weeks and 18 weeks, respectively. The major toxicity were grade 3 or 4 neutropenia (6%). Other toxicity were myalgia, neuropathy, nausea and oral mucositis, but all of them were usually mild (grade 1, 2) and recovered spontaneously. There were no treatment- related deaths. CONCLUSIONS: This single low dose paclitaxel chemotherapy is highly tolarable with activity comparable to that of conventional dose regimens especially in elderly advanced non-small cell lung cancer.

Pretreatment of Diltiazem Ameliorates Endotoxin-Induced Acute Lung Injury by Suppression of Neutrophilic Oxidative Stress / 결핵및호흡기질환

BACKGROUND: Acute respiratory distress syndrome (ARDS) is characterized by severe inflammatory pulmonary edema of unknown pathogenesis. To investigate the pathogenesis of ARDS associated with neutrophilic oxidative stress, the role of phospholipase A2 (PLA2) was evaluated by the inhibition of calcium channel. METHODS: In Sprague-Dawley rats, acute lung injury (ALI) was induced by the instillation of E.coli endotoxin (ETX) into the trachea. At the same time, diltiazem was given 60 min prior to tracheal instillation of ETX. Parameters of ALI such as lung and neutrophil PLA2, lung myeloperoxidase (MPO), BAL neutrophils, protein, surfactant were measured. Production of free radicals from neutrophils was measured also. Morphological studies with light microscope and electron microscope were carried out and electron microscopic cytochemistry for detection of free radicals was performed also. RESULTS: Diltiazem had decreased the ALI parameters effectively in ETX given rats and decreased the production of free radicals from neutrophils and lung tissues. Morphological studies denoted the protective effects of diltiazem. CONCLUSION: Diltiazem, a calcium channel blocker, was effective in amelioration of ALI by the suppression of neutrophilic oxidative stress mediated by PLA2 activation.

Efficacy of weekly paclitaxel and concurrent radiation therapy for locally advanced non-small cell lung cancer / 대한내과학회지

BACKGROUND: Combined modality therapy is standard treatment of unresectable, locally advanced stage III non-small cell lung cancer (NSCLC). However, the optimal chemotherapy regimen and duration of chemotherapy remain a matter of debate. We evaluated the efficacy and feasibility of concurrent chemoradiation therapy (CCRT) in patients with locally advanced NSCLC. METHODS: PS 0-2 patients with histologically proven inoperable stage III NSCLC were eligible for this trial. The patients received paclitaxel (60mg/m2) on days 1, 8, 15, 22, 29, 36 with a concurrent radiotherapy (5days/week, 1.8Gy/day) starting day 1 with a total dose of 63 Gy. After CCRT, four cycles of consolidation chemotherapy with paclitaxel (140mg/m2) and carboplatin (AUC 5) was administered to patients with a partial, complete remission or stable disease. RESULTS: Twenty eight patients with locally advanced NSCLC enrolled in this study. The median age of the patients was 60 years. Of the 28 patients, 19 received scheduled CCRT. Overall response rate was 71.4% including 5 complete responses and 15 partial responses. Grade 3 or 4 pulmonary complication was observed in 7 patients and 3 patients died of pneumonitis. The median overall survival was 17.5 months (95% CI, 12.5-22.5). The median progression free survival was 8.0 months (95% CI, 4.1-11.9). CONCLUSIONS: CCRT including paclitaxel in patients with locally advanced NSCLC led to an encouraging response rate and survival, but resulted in high incidence of severe pulmonary complication.

Effect of Doxycycline on the Acute Lung Injury Induced by Gut Ischemia/Reperfusion / 결핵

BACKGROUND: Phospholipase A2 (PLA2) has been known to be involved in the pathogenesis of acute lung injury (ALI) including ARDS. Since doxycycline has the property of inhibiting secretory group II PLA2, the therapeutic effect of doxycycline hyclate was investigated for gut ischemia/reperfusion (I/R)-induced ALI in Sprague-Dawley rats. METHODS: ALI was induced in Sprague-Dawley rats by clamping of the superior mesenteric artery for 60 min, followed by 120 min of reperfusion. To confirm the pathogenetic mechanisms of this ALI associated with neutrophilic oxidative stress, we measured bronchoalveolar lavage (BAL) protein content and lung MPO, and performed cyto chemical electron microscopy for detection of free radicals, assay of PLA2 activity and cytochrome-c reduction assay. RESULTS: In gut I/R-induced ALI rats, protein leakage, pulmonary neutrophil accumulation, free radical production and lung PLA2 activity were all increased. These effects were reversed by doxycycline hyclate. CONCLUSION: Doxycycline appars to be effective in ameliorating the gut I/R-induced ALI by inhibiting PLA2, thereby decreasing the production of free radicals from neutrophils.

Acute renal failure by intermittent rifampin administration in leprosy patient / 대한내과학회지

A 74-years-old female with leprosy was hospitalized because of nausea, vomiting, and oliguria after ingestion of rifampin 600 mg once for one day. At this time, after taking the second dose of rifampin, she presented with anemia, hepatic dysfunction and oliguric renal failure. Renal biopsy specimen showed acute interstitial nephritis and tubular necrosis without immunoglobulin deposition on immunofluorescence examination. Peripheral blood smear showed fragmented red blood cells (RBCs) and direct Coombs' test was positive. Indirect antiglobulin test with patient's serum using RBCs sensitized in vitro with rifampin showed positive finding. The renal failure and systemic symptoms were improved after discontinuation of rifampin, high dose prednisolone administration and several sessions of hemodialysis.

Non small cell lung cancer diagnosed by EUS guided fine needle aspiration / 대한내과학회지

No abstract available.

Evaluation of Sensitivity and Specificity of MAGE A1-6 RT-nested PCR as a Cancer Detection Method / 대한진단검사의학회지

BACKGROUND: The aim of this study is to evaluate the sensitivity and specificity of MAGE (Melanoma Antigen Gene) A1-6 RT-nested PCR as a detection method for cancer cells. METHODS: From February 2001 and December 2002, various samples [cancer tissue, sputum, induced sputum, broncho-alveolar lavage (BAL), blood, urine and cervical brush] were obtained from 355 cancer patients. Moreover, 316 samples, including cancer adjacent normal tissue, blood, urine and sputum were collected for the negative controls. MAGE A1-6 RT-nested PCR was performed and the results were evaluated with clinical diagnosis. The sensitivity of the MAGE assay was compared with that of the telomerase assay and cytologic examination using 26 sputa of lung cancer patients. RESULTS: The average sensitivity of the MAGE assay in cancer tissues was 79% (85% in squamous carcinoma and 70% in adenocarcimona). The sensitivity in body fluids was 57% (9-27% in blood, 59% in sputum, 68% in urine, more than 70% in induced sputum and BAL, and 87% in pleural fluid and cervical brush). In the negative controls, the positive rates were less than 8.9% in normal tissues and 2% in blood, sputum and urine. The average sensitivity of the MAGE RT-PCR, telomerase assay and cytologic examination was 61.5%, 26.9% and 15.4%, respectively. CONCLUSIONS: The MAGE A1-6 RT-PCR showed excellent sensitivity and specificity. Therefore, it could be effectively utilized as a cancer detection method in the clinical laboratory.

Evaluation of Sensitivity and Specificity of MAGE A1-6 RT-nested PCR as a Cancer Detection Method / 대한진단검사의학회지

BACKGROUND: The aim of this study is to evaluate the sensitivity and specificity of MAGE (Melanoma Antigen Gene) A1-6 RT-nested PCR as a detection method for cancer cells. METHODS: From February 2001 and December 2002, various samples [cancer tissue, sputum, induced sputum, broncho-alveolar lavage (BAL), blood, urine and cervical brush] were obtained from 355 cancer patients. Moreover, 316 samples, including cancer adjacent normal tissue, blood, urine and sputum were collected for the negative controls. MAGE A1-6 RT-nested PCR was performed and the results were evaluated with clinical diagnosis. The sensitivity of the MAGE assay was compared with that of the telomerase assay and cytologic examination using 26 sputa of lung cancer patients. RESULTS: The average sensitivity of the MAGE assay in cancer tissues was 79% (85% in squamous carcinoma and 70% in adenocarcimona). The sensitivity in body fluids was 57% (9-27% in blood, 59% in sputum, 68% in urine, more than 70% in induced sputum and BAL, and 87% in pleural fluid and cervical brush). In the negative controls, the positive rates were less than 8.9% in normal tissues and 2% in blood, sputum and urine. The average sensitivity of the MAGE RT-PCR, telomerase assay and cytologic examination was 61.5%, 26.9% and 15.4%, respectively. CONCLUSIONS: The MAGE A1-6 RT-PCR showed excellent sensitivity and specificity. Therefore, it could be effectively utilized as a cancer detection method in the clinical laboratory.

A Case of Amiodarone-Induced Pulmonary Toxicity After a Long Course of a Low Dose Therapy / 결핵

Amidarone is one of the most commonly prescribed anti-arrythmic agents for almost all arrythmias, whether atrial or ventricular in origin. There are several side effects associated with amiodarone therapy. These include corneal deposits, abnormal liver function tests, hyper and hypothyroidism, bluish discolorations of the skin, bone marrow suppression, coagulopathies, peripheral neuropathies, and pulmonary toxicity. Amiodarone-induced pulmonary toxicity(APT), which was first described in 1980, is potentially serious side effects that are believed to develop in 5% of patients. Doctors often assume that APT occurs only when high amiodarone doses are used for a long time, but in practice a low maintenance dose of amiodarone may also be toxic. In this report, a case of amiodarone-induced pulmonary toxicity after a long course of a low dose therapy for refractory supraventricular arrythmia is described.

The Clinical Characteristics in Patients with Lung Cancer Under 45 Years of Age / 결핵

BACKGROUND: Lung cancer is the leading cause of cancer-related mortality in both men and women. Although most cases of lung cancer occur in the sixth to eighth decades of life, 5 to 10% are diagnosed at a young age. There are characteristic features in young patients with lung cancer that differ from those in older patients with lung cancer. The purpose of this study was to determine if the basal characteristics and survival in young patients with lung cancer differed from those of old patients. METHODS: We retrospectively reviewed the medical records of 94 young patients who were under 45 years of age and compared them with 1,728 old patients (= 46 years of age) in 4 medical schools at Daegu, between August 1986 and July 1995. RESULTS: Significantly more female patients and adenocarcinomas were found in the young patients group, when compared to the old patients. Cough and sputum were the most frequent presenting symptom in both age groups. This was followed by chest discomfort, dyspnea and hemoptysis. The rates of smoking was significantly lower in the young patients. There was no statistical difference in the severity of the disease in terms of staging between the two age groups. Young patients received treatment more frequently than the older patients. The location of the primary tumors was equally frequent in both the upper and lower lobe. However, the survival was better in the young patients (median survival time, 67.3 weeks), when compared to the old patients (median survival time, 26.8 weeks) (p<0.05). CONCLUSION: Females and adenocarcinoma patients were predominant in young patients with lung cancer. The young patients appeared to have significantly better prognosis.

A Case of Pulmonary Alveolar Proteinosis Associated with Pulmonary Tuberculosis / 결핵

Pulmonary alveolar proteinosis(PAP) is a disorder in which an insoluble, proteinaceous material, rich in phospholipids, is deposited in the alveoli and bronchioles. The deficiency in the clearance and degradation of the i ntra-alveolar phospholipoproteinaceous material in PAP most likely represents a dysfunction of the type II pneumocytes. Although the pathogenesis and causative treatment of PAP is unclear a whole lung bronchopulmonary lavage is a relatively safe and effective treatment. Here we experienced a case of pulmonary alveolar proteinosis in a 62 year old female patient who had pulmonary tuberculosis approximately 20 years ago. She complained of aggravated dyspnea and chronic cough, and presented fine inspiratory crackles at both lung fields. diffuse ground glass opacity with some area of consolidation and smooth interlobular septal thickenings in both upper, right middle lobes, and a portion of right lower lobe. Optical microscopy of the lung tissue obtained by an open lung biopsy many granulomas containing acid-fast smear positive bacilli and diffuse homogeneous PAS-positive fluid in the alveolar space. Immunohistochemical stain showed surfactant A in the alveolar space. Antituberculosis drugs with bronchoalveolar lavage were used to treat the disease. There after she showed improvement in her symptoms and a partial improvement in the chest X-ray and HRCT findings. We present a case of PAT associated with pulmonary tuberculosis.

A Case of Pulmonary Alveolar Proteinosis Associated with Pulmonary Tuberculosis / 결핵

Pulmonary alveolar proteinosis(PAP) is a disorder in which an insoluble, proteinaceous material, rich in phospholipids, is deposited in the alveoli and bronchioles. The deficiency in the clearance and degradation of the i ntra-alveolar phospholipoproteinaceous material in PAP most likely represents a dysfunction of the type II pneumocytes. Although the pathogenesis and causative treatment of PAP is unclear a whole lung bronchopulmonary lavage is a relatively safe and effective treatment. Here we experienced a case of pulmonary alveolar proteinosis in a 62 year old female patient who had pulmonary tuberculosis approximately 20 years ago. She complained of aggravated dyspnea and chronic cough, and presented fine inspiratory crackles at both lung fields. diffuse ground glass opacity with some area of consolidation and smooth interlobular septal thickenings in both upper, right middle lobes, and a portion of right lower lobe. Optical microscopy of the lung tissue obtained by an open lung biopsy many granulomas containing acid-fast smear positive bacilli and diffuse homogeneous PAS-positive fluid in the alveolar space. Immunohistochemical stain showed surfactant A in the alveolar space. Antituberculosis drugs with bronchoalveolar lavage were used to treat the disease. There after she showed improvement in her symptoms and a partial improvement in the chest X-ray and HRCT findings. We present a case of PAT associated with pulmonary tuberculosis.

A Case of the Membranous Glomerulonephritis Associated with Squamous Cell Lung Cancer / 결핵

The nephrotic syndrome that occurs in the absence of renal vein thrombosis, amyloidosis, neoplastic infiltration of the kidneys is an unusual but a well recognized paraneoplastic syndrome. The most frequently reported neoplasms associated with nephrotic syndrome are Hodgkin's disease and various carcinomas. The most common renal lesions are membranous glomerulonephritis(MGN) associated with carcinomas and minimal change lesions associated with Hodgkin's disease. Approximately 40% to 45% of patients clinically manifest the MGN symptoms prior to the diagnosis of the tumor, 40% simultaneously with the tumor and the remaining 15% to 20% following the tumor. Therefore, evaluating the underlying malignancy in patients with MGN is important. Here we report a patient with squamous cell lung cancer, which was detected 12 months after a MGN had been diagnosed, with a review of the relevant literature.

Analysis of Treatment Failure for the Pulmonary and Neck Tuberculosis / 결핵

BACKGROUND: There are only a few studies regarding the causes of treatment failure for tuberculosis. Therefore, this study aimed to determine the causes of intractable tuberculosis. METHODS: M.tuberculosis, differentiated MOTT (Tycobacterium Other Than Tuberculosis) were isolated, and the RFLP (Restriction fragments length polymorphisms) pattern was analyzed from 204 patients with pulmonary tuberculosis and 53 suffering from neck tuberculosis. The IL-1β, IL-12, *1 IFNγ and *2 TNFαblood levels were measured. All patients were regularly followed for 18 months after treatment. RESULTS: There was no correlation between the RFLP patterns of M.tuberculosis treatment failure. From the 204 cases, 31.9% were intractable. The characteristics of patients with intractable tuberculosis were old age, being male and recurrent cases. The causes of treatment failure were identified as follows ; a decrease in the IL-12(59.4%) concentration, drug resistant strain(54.7%), irregular medication(15.4%), MOTT(6.2%) and a heavy infection(4.6%). The causes of all cases of intractable tuberculosis could be investigated. The IL-12 concentration in the blood was significantly lower in the intractable cases, where it disclosed a maximum sensitivity(64.7%) and specificity(75.4%) at 165.0 pg/ml. Most of the 53 cases on neck node tuberculosis were treated successfully. Therefore, we were unable to analyze the cause of treatment failure. CONCLUSION: A decrease in the blood IL-12 concentration and drug resistant strains were identified as the most significant causes of treatment failure for tuberculosis. In Korea, infection by clusters were prevalent, but no difference in the clinical course between clusters and non-clusters could be found.

A Clinical study of tuberculous lymphadenitis / 결핵

BACKGROUND: The aim of this study was to analyze the clinical manifestations and efficacy of treatment regimens in order to determine the adequate combination of anti-tuberculotic agent and duration of treatment for tuberculous lymphadenitis. METHODS: We made a review of 373 patients with tuberculous lymphadenitis, who were admitted to four medical college hospitals in Taegu Korea from 1989 to 1998, and their diagnoses were confirmed histologically and bacteriologically. RESULTS: The incidence of tuberculous lymphadenitis was 71.3% in women and 57.7% were between the ages of 20 and 39 years. The most common symptom was painless swelling. The most commonly involved lymph nodes were unilateral superficial cervical lymph node groups. Tuberculous lymphadenitis was accompanied with active pulmonary tuberculosis, commonly. The sensitivity of fine needle aspiration(FNA) in tuberculous lymphadenitis was 79.6% and 92.2% of the patients had a strong positive reaction to the tuberculin skin test. The most commonly prescribed anti-tuberculotic regimen was the combination of INF, RMP, EMB and PZA(62.6%). Eighty percent of patient were treated for 9-12 months. There was no significantly difference in the recurrence rate of tuberculous lymphadenitis between the combinations of anti-tuberculotic agent, including INF and RMP, and between the durations of treatment, for a period of 6 months of treatment, for a period of 6 months of more. CONCLUSION: The combination of FNA cytologic examination and tuberculin skin test may be helpful in the diagnosis of tuberculous lymphadenitis. We propose that the combination of anti-tuberculotic agents, INH, RMP, EMB, and PZA, be prescribed to patients for 6 to 9 months.

Restriction fragment length polymorphism analysis of Mycobacterium tuberculosis isolated from Taegu / 대한임상병리학회지

BACKGROUND: To investigate epidemiology of a specific strain, and evaluate correlation between Mycobacterium tuberculosis restriction fragment length polymorphism (RFLP) and antimicrobial susceptibility, we studied about Mycobacterium tuberculosis RFLP isolated from Taegu area. METHODS: From Oct. 1997 and Mar. 1999, we isolated 54 strains of M. tuberculosis from the patients visiting Catholic University of Taegu Hyosung, Taegu, Korea. We studied their drug susceptibility and analyzed the Pvu treated RFLP using digoxigenin labeled IS6110 probe. RESULTS: Fifty-three had more than 6 bands of RFLP and strains with 10 bands were predominant (15 strain). Cluster analysis reveals eleven distinct clusters showing 57.4% of clustered rate (31 strains from A to K) and 35 independent patterns showing 64.8% of the diversity rate at 70% similarity level. Cluster A was the largest group (7 strains) and the next was cluster B (5 strains). Most of the patients with cluster A lived in Taegu city (85.7%) and all of 2 cluster K patients lived in Euisung area. There was no correlation between RFLP pattern and antimicrobial susceptibility, but all two strains of cluster H were resistant to isoniazid. Strains of clustered were also prevalent in the people of middle class. CONCLUSIONS: Compared to the RFLP analysis in the developed countries, Korea disclosed lower rate of diversity and higher clustered patterns of M. tuberculosis. The clustered strains were also prevalent among the people of middle class.