Background: The objective of this study was to assess the validity and reliability of the Korean version of chronic obstructive pulmonary disease assessment test (CAT) and Dyspnea-12 Questionnaire for patients with bronchiectasis or tuberculous destroyed lung. Methods: For 62 bronchiectasis patients and 37 tuberculous destroyed lung patients, 3 questionnaires including St. George's Respiratory Questionnaires (SGRQ), CAT, and Dyspnea-12 were obtained, in addition to spirometric measurements. To assess the validity of CAT and Dyspnea-12, correlation with SGRQ was evaluated. To assess the reliability of CAT and Dyspnea-12, Cronbach's ${\alpha}$ coefficient was calculated. Results: The mean ages of the patients were $60.7{\pm}8.3$ years in bronchiectasis and $64.4{\pm}9.3$ years in tuberculous destroyed lung. 46.8% and 54.1% were male, respectively. The SGRQ score was correlated with the score of the Korean version of CAT (r=0.72, p<0.0001) and Dyspnea-12 (r=0.67, p<0.0001) in bronchiectasis patients. The SGRQ score was correlated with the score of CAT (r=0.86, p<0.0001) and Dyspnea-12 (r=0.80, p<0.0001) in tuberculous destroyed lung patients. The Cronbach's ${\alpha}$ coefficient for the CAT and Dyspnea-12 were 0.84 and 0.90 in bronchiectasis, and 0.88 and 0.94 in tuberculous destroyed lung, respectively. Conclusion: We found that Korean version of CAT and Dyspnea-12 are valid and reliable in patients with tuberculous destroyed lung and bronchiectasis.

Background: Pyrazinamide (PZA) is an effective antitubercular drug that becomes toxic to Mycobacterium tuberculosis when converted to pyrazinoic acid by pyrazinamidase (PZase), encoded by mycobacterial pncA. A strong association was noted between the loss of PZase activity and PZA resistance. The causative organisms in extrapulmonary tuberculosis are rarely cultured and isolated. To detect pncA mutations in specimens from extrapulmonary tuberculosis as confirmative diagnosis of mycobacterial infection and alternative susceptibility test to PZA. Methods: Specimens were collected from clinically proven extrapulmonary tuberculosis. pncA was sequenced and compared with wild-type pncA. Results: pncA from 30 specimens from 23 donors were successfully amplified (56.6% in specimens, 59% in donors). Six mutations in pncA were detected (20.0% in amplified specimens, 26.1% in specimen donors) at nucleotide positions of 169, 248 and 419. The mutation at position 169 results in substitution of aspartic acid for histidine, a possible allelic variation of M. bovis that have intrinsic PZA resistance. The mutation at position 248 changes proline into arginine and that at position 419, arginine into histidine. Conclusion: DNA-based diagnosis using pncA may be simultaneously useful for the early diagnosis of mycobacterial infection and the rapid susceptibility to PZA in extrapulmonary tuberculosis. A potential implication of pncA allelic variation at 169 might be suggested as a rapid diagnostic test for M. bovis infection or Bacille Calmette-Gu$\acute{e}$rin (BCG) reactivation.

Background: Tracheostomy is a common procedure for patients requiring prolonged mechanical ventilation. However, the timing of tracheostomy is quite variable. This study was performed to find out the factors determining the timing of tracheostomy in medical intensive care unit (ICU). Methods: Patients who were underwent tracheostomy between January 2008 and December 2009 in the medical ICU of Seoul National University Hospital were included in this retrospective study. Results: Among the 59 patients, 36 (61.0%) were male. Median Acute Physiology And Chronic Health Evaluation (APACHE) II scores and Sequential Organ Failure Assessment scores on the admission day were 28 and 7, respectively. The decision of tracheostomy was made on 13 days, and tracheostomy was performed on 15 days after endotracheal intubation. Of the 59 patients, 21 patients received tracheostomy before 2 weeks (group I) and 38 were underwent after 2 weeks (group II). In univariate analysis, days until the decision to perform tracheostomy (8 vs. 14.5, p<0.001), days before tracheostomy (10 vs. 18, p<0.001), time delay for tracheostomy (2.1 vs. 3.0, p<0.001), cardiopulmonary resuscitation (19.0% vs. 2.6%, p=0.049), existence of neurologic problem (38.1% vs. 7.9%, p=0.042), APACHE II scores (24 vs. 30, p=0.002), and $PaO_2/FiO_2$ <300 mm Hg (61.9% vs. 91.1%, p=0.011) were different between the two groups. In multivariate analysis, APACHE II scores${\geq}20$ (odds ratio [OR], 12.44; 95% confidence interval [CI], 1.14~136.19; p=0.039) and time delay for tracheostomy (OR, 1.97; 95% CI, 1.11~3.55; p=0.020) were significantly associated with tracheostomy after 2 weeks. Conclusion: APACHE II scores${\geq}20$ and time delay for tracheostomy were associated with tracheostomy after 2 weeks.

Background: The aim of this study was to analyze clinical situations requiring rigid bronchoscopy and evaluate usefulness of rigid bronchoscopic intervention in benign or malignant airway disorders. Methods: We retrospectively reviewed 29 patients who underwent rigid bronchoscopy from November 2007 to February 2011 at St. Paul's Hospital, The Catholic University of Korea School of Medicine. Results: Of the 29 patients, the most frequent underlying etiology was benign stenosis of trachea (n=20). Of those 20 patients, 16 had post-intubation tracheal stenosis (PITS), 2 had tracheal stenosis due to inhalation burn (IBTS) and other 2 had obstructive fibrinous tracheal pseudomembrane (OFTP). Other etiologies were airway malignancy (n=6), endobronchial stenosis due to tuberculosis (n=2), and foreign body (n=1). For treatment, silicone stent insertion was done in 16 cases of PITS and IBTS and mechanical removal was performed in 2 cases of OFTP. In 6 cases of malignant airway obstruction mechanical debulking was performed and silicone stents were inserted additionally in 2 cases. Balloon dilatation and electrocautery were used in 2 cases of endobronchial stenosis due to tuberculosis. In all cases of stent, airway obstructive symptom improved immediately. Granulation tissue formation was the most common complication. Conclusion: Tracheal stenosis was most common indication and silicone stenting was most common procedure of rigid bronchoscopy in our center. Rigid bronchoscopic procedures, at least tracheal silicone stenting, should be included in pulmonary medicine fellowship programs because it is a very effective and indispensable method to relieve critical airway obstruction which needs training to learn.

Background: This study investigated the clinical characteristics and risk factors of the severity of pandemic influenza A (H1N1) 2009 infection in pediatric patients in Busan and Gyeongsangnam-do. Methods: Cases of influenza A (H1N1) 2009 in patients under the age of 18 years, confirmed by reverse transcription polymerase chain reaction, at Pusan National University Hospital and Pusan National University Yangsan Hospital from the last week of August 2009 through the last week of February 2010 were retrospectively analyzed. Results: Of the 3,777 confirmed cases of influenza A (H1N1) 2009, 2,200 (58.2%) were male and 1,577 (41.8%) were female. The average age of the patients was $8.4{\pm}4.8$ years. The total cases peaked during 44th to 46th week. Most of the patients were in the 5- to 9-year-old age group. Oseltamivir was administered to 2,959 (78.3%) of the patients. 221 patients (5.9%) were hospitalized, age an average of $6.7{\pm}4.5$ years. The average duration of hospitalization was $7.4{\pm}5.6$ days. One hundred cases (45.2%) had pneumonia. Risk factors for hospitalization included male gender, <2 years of age, and underlying disease. Children with asthma were at very high risk of hospitalization, over 20 times the non-asthmatic children (odds ratio [OR], 21.684; confidence interval [CI], 13.295~39.791). Likewise the children with neurologic deficits faced a 16 times higher risk (OR, 15.738; CI, 7.961~31.111). Ten of the patients (4.5%) were admitted to the intensive care unit, and eight (3.6%) required mechanical ventilation. Conclusion: Of the pediatric patients with pandemic influenza A (H1N1) 2009, most of the patients were in the 5- to 9-year-old age group. Risk factors for hospitalization included male gender, <2 years of age, and underlying disease. The most common complication was pneumonia. The very high risk of severe morbidity in children with asthma or neurologic disease shows the critical importance of targeted vaccine coverage, special awareness and swift care by both guardians and primary care providers.

Congenital cystic adenomatoid malformation (CCAM) is an uncommon, nonhereditary anomaly caused by arrest of lung. Patients with CCAM may present with respiratory distress as newborns, or may remain asymptomatic until later in life. CCAM type I is rarely found in association with bronchial atresia (BA) in adults; we present such a case. Case: A 54-year-old female presented with chronic cough and blood-tinged sputum. Physical examination and laboratory tests were unremarkable. Chest radiographs and a CT scan of the chest showed multiple large air-filled cysts consistent with a CCAM in the right lower lobe, and an oval-shaped opacity in the distal right middle lobal bronchus. Based on the radiologic findings, right middle lobectomy and a medial basal segmentectomy of the right lower lobe were performed via a thoracotomy. These lesions were consistent with Stocker's Type I CCAM and BA in the different lobes.

Carbohydrate antigen 19-9 (CA19-9) is a specific tumor marker of the biliary, pancreatic and gastrointestinal tracts. CA19-9 is occasionally elevated in serum in patiens with benign pulmonary diseases such as bronchiectasis, idiopathic interstitial pneumonia or collagen disease-associated pulmonary fibrosis. Intralobar pulmonary sequestration is an uncommon congenital lung anomaly. It is dissociated from the normal tracheobronchial tree and is supplied by an anomalous systemic artery. There have been some reports of elevation of CA19-9 in this lesion. We report a case of intralobar pulmonary sequestration with elevated serum CA19-9 in a 29-year-old man who was diagnosed with bronchiectasia of left lower lung field on general check up. He had no evidence of any malignant disease in pancreatobiliary or gastrointestinal tracts. Elevated serum CA19-9 level might be encountered with benign pulmonary disease such as pulmonary sequestration.