Background : Fluoroquinolone drugs are an important anti-tuberculous agent for the treatment of multi-drug resistant tuberculosis. However, many drugs belonging to the fluoroquinolones have different cross resistance to each other. Methods : Sixty-three ofloxacin (OFX) resistant and 10 pan-susceptible M. tuberculosis isolates were selected, and compared for their cross resistance using a proportion method on Lowenstein-Jensen media, containing ofloxacin (OFX), ciprofloxacin (CIP), levofloxacin (LVX), moxifloxacin (MXF), gatifloxacin (GAT) and sparfloxacin (SPX), at concentrations ranging from 0.5 to 3µg/ml. DNA extracted from the isolates was directly sequenced after amplifying from the gyrA and gyrB genes. Results : The 63 OFX resistant M. tuberculosis isolates showed complete cross resistance to CIP, but only 90.5, 44.4, 36.5 and 46.0% to LVX, MXF, GAT, and to SPX, respectively. Fifty-one of the isolates (81.0%) had point mutations in codons 88, 90, 91 and 94 in gyrA, which are known to be correlated with OFX resistance. The Gly88Ala, Ala90Valand Asp94Ala mutations in gyrA showed a tendency to be susceptible to MXF, GAT and SPX. Only 4 isolates had mutations in the gyrB gene, which did not affect the OFX resistance. Conclusion : About 60% of the OFX resistant M. tuberculosis isolates were susceptible to GAT, SPX and MXF. These fluoroquinolones may be useful in the treatment of TB patients showing OFX resistance. (Tuberc Respir Dis 2005; 59: 250-256)
Background : Ethambutol(EMB) is one of the first-line drugs included in short-course anti-tuberculosis therapy. The point mutations in embB gene have been speculated to be associated EMB resistance. However, detection of embB mutations at these positions have been observed in both EMB-susceptible isolates; thus, it remains controversial whether these mutations are associated with EMB resistance Methods : The 36 M. tuberculosis isolates were selected from clinical isolates which tested susceptible to EMB and resistant to at least one drug. DNA extracted from the isolates was analyzed by amplifying embB gene. The PCR products were purified and directly sequenced. We reviewed the history of past drug susceptibility test results. Results : Out of 36 EMB-susceptible strains, 3 strains (8.3%) had a mutation in codon 306 or 406 of the embB gene. These three strains had at least isoniazid resistance. They grew at 1.0 mcg/ml of EMB in Lowenstein-Jensen media. The patients of the strains were continuously smear-positive for over 3 years despite taking TB therapy. One strain had been EMB-resistant in past drug susceptibility tests. Conclusion : EMB-susceptible strains containing embB mutation may be caused by decreased viability in vitro test not by itself. (Tuberc Respir Dis 2005; 59: 266-271)
Background : The immune responses mediated by CD8+T cells are known to be significant in controlling M. tuberculosis infections. In order to determine the role of cytotoxic CD8+T cells in the protective immune mechanism in latently infected subjects, this study examined whether or not the cytotoxic immune responses of CD8+T cells specific to the M. tuberculosis somatic antigens are induced in BCG vaccinated healthy subjects. Methods : Cytotoxicity and IFN-γ elispot assays were used to investigate the activities of CD8+T cells specific for the thyA30-38 peptide epitope in circulating peripheral blood mononuclear cells (PBMC) from BCG-vaccinated HLA-A*0201 and A*0206 subjects. Results : The results indicate the cytotoxic and IFN-γ immune responses of CD8+T cells specific for thyA30-38 were induced in BCG vaccinated healthy subjects. Conclusion : The cytotoxic and IFN-γ responses by CD8+T cells specific for the M. tuberculosis somatic antigens are induced in BCG-vaccinated subjects, and appear to be involved in the protective immune mechanism in latently infected people against a M. tuberculosis infection. (Tuberc Respir Dis 2005; 59: 272-278)
Background : Obstructive sleep apnea syndrome (OSAS) is believed to have multifactorial causes. The major risk factors for OSAS are obesity, narrowed upper airways, and abnormal cranial-facial structures. A genetic basis for OSAS has been also suggested by reports of families with many members affected. This study analyzed the HLA typing in patients with OSAS to determine the possible role of genetics in OSAS. Methods : Twenty-five Korean patients with OSAS (1 woman and 24 men; age range 30-66 years) were enrolled in this study. A diagnosis of OSAS was made using full-night polysomnography. The control group consisted of 200 healthy Korean people. Serologic typing of the HLA-A and B alleles was performed in all patients using a standard lymphocyte microcytotoxicity test. Analysis of the polymorphic second exons of the HLA-DRB1 gene was performed using a polymerase chain reaction-sequence specific oligonucleotide probe. Results : The allele frequency of HLA-A11 was significantly lower in patients with OSAS compared with the controls (p<0.05). The HLA-B allele frequencies in the patients and controls had a similar distribution. Analysis of the HLA- DRB1 gene polymorphisms showed an increased frequency of DRB1*09 in the OSA patients compared with the controls (p<0.05). When the analysis was performed after dividing the OSAS patients according to the severity of apnea, the allele frequency of HLA-DRB1*08 was significantly higher in the severe OSA patients (apnea index >45) than in the controls (p<0.05). Conclusion : This study revealed an association between OSAS and the HLA-A11 and DRB1*09 alleles as well as association between the disease severity and the HLA-DRB1*08 allele in Korean patients. These results suggest that genetics plays an important role in both the development and the disease severity of OSAS. (Tuberc Respir Dis 2005; 59: 298-305)
Hyponatremia which is due to excessive sodium loss in the urine and decrease in extracellular fluid volume following an acute or chronic central nervous system injury, has been conjunctively described as cerebral salt wasting syndrome (CSWS). This syndrome is often confused with dilutional hyponatremia due to inappropriate secretion of antidiuretic hormone. Accurate diagnosis and management are mandatory for improvement of the course of the disease. This report describes a case of a 31-year-old male patient with CSWS associated with tuberculous meningitis. The patient exhibited hyponatremia, polyuria, excessive natriuresis, volume depletion, and hypotension. He was diagnosed to manifest CSWS and was treated by administration of fluids, salt, and fludrocortisone. After the respective treatments, symptoms of polyuria and hypotension were gradually resolved and hyponatremia was corrected. (Tuberc Respir Dis 2005; 59: 306-310)
Pulmonary aspergillosis may present with three different features, according to the immune status of the host. These forms are invasive aspergillosis, allergic bronchopulmonary aspergillosis (ABPA) or aspergilloma. Bronchial involvement is an uncommon type of invasive pulmonary aspergillosis. We encountered an unusual case of an endobronchial aspergillosis that completely obstructed the left upper lobe, which was initially thought to be lung cancer. We report this case along with a review of the relevant literature. (Tuberc Respir Dis 2005; 59: 311-314)
Pulmonary aspergillosis may present with three different features, according to the immune status of the host. These forms are invasive aspergillosis, allergic bronchopulmonary aspergillosis (ABPA) or aspergilloma. Bronchial involvement is an uncommon type of invasive pulmonary aspergillosis. We encountered an unusual case of an endobronchial aspergillosis that completely obstructed the left upper lobe, which was initially thought to be lung cancer. We report this case along with a review of the relevant literature. (Tuberc Respir Dis 2005; 59: 311-314)
Serous effusions have been most commonly associated with ascites, pericardial effusion, and heart failure. But, they have been considered to be an unusual form of complication in hypothyroidism and pleural effusion, which has been observed as an isolated finding in hypothyroidism is apparently rare and complete analysis of these types of hypothyroid-associated pleural effusions has yet not been described. We report a case of hypothyroidism associated with unilateral pleural effusion in a 77 year-old male patient who was improved through levothyroxine sodium with brief review of the literature. (Tuberc Respir Dis 2005; 59: 321-325)
A case of 51-year-old woman with a malignant solitary pulmonary nodule (SPN) that exhibited no growth over a period of 4 years is reported. Surgical wedge resection revealed an adenocarcinoma upon intra-operative frozen examination. The operation was completed with a right upper lobectomy and complete lymphadenectomy. The authors recommend an early surgical procedure for any SPNs due to risk factors for developing lung cancer. (Tuberc Respir Dis 2005; 59: 326-329)