• Tuberculosis and Respiratory Diseases
• /
• v.47 no.4
• /
• pp.460-470
• /
• 1999

Background : In 1993, American Thoracic Society (ATS) recommended a guideline for the initial management of adults with community-acquired pneumonia(CAP). However, etiologic organisms and medical system in Korea seem to be different from those in Western countries. Retrospective analysis was done to evaluate the efficacy of antibiotics chosen by ATS guideline in the treatment of Korean patients with CAP admitted to a tertiary university medical center. Methods : Hospitalized patients with CAP at Samsung Medical Center from April 1997 through March 1998 were retrospectively reviewed. Patients who fulfilled all of the following criteria were included in this study : (1) fever ${\geq}38^{\circ}C$ (2) purulent sputum (3) pulmonary infiltrates on chest X-ray. Patients were classified as : 1) ATS group ; patients whose initial antibiotics were chosen by ATS guideline 2) Non-ATS overuse group ; additional antibiotics administered more than those of ATS guideline, and 3) Non-ATS underuse group ; initial antibiotics were insufficient to ATS guideline. Response of empirical antibiotics and etiologic organisms of 3 groups were identified. Results : Sixty-four patients were enrolled. Thirty-six patients were classified into ATS group, 10 patients Non-ATS overuse group, and 18 patients Non-ATS underuse group. Thirty-three patients of 36 ATS group, 9 patients of 10 Non-ATS overuse group, and 14 patients of 18 Non-ATS underuse group showed improvement by initial empirical antibiotics. There was no statistical difference in antibiotic response between 3 groups (p>0.05). S. pneumoniae (12.5%), K. pneumoniae (9.4%), and P. aeruginosa (4.7%), Mycoplasma (3.1%) were the most commonly isolated organisms. In 18 patients with severe CAP, P. aeruginosa was isolated only in 1 patient and Legionella organism not isolated. Conclusion : Initial empirical antibiotics chosen by ATS guideline were effective in the management of Korean patients with CAP admitted to a tertiary hospital. However, well-designed large-scale prospective study is needed to identify etiologic organisms and choose an adequate initial empirical antibiotics in Korean adults patient with severe CAP.

• Tuberculosis and Respiratory Diseases
• /
• v.44 no.5
• /
• pp.1072-1082
• /
• 1997

Background : To characterize the clinical features and determine the prognostic factors of severe community-acquired pneumonia. This study is the first of its kind in Korea. Methods : Recruited were 40 patients diagnosed as severe community-acquired pneumonia in Hallym University Hospital from January 1, 1989 through July 31, 1996. Patients were analysed retrospectively for age, sex, underlying disease, respiration rate, hypoxemia, requirement of mechanical ventilation, involvement on chest radiograph, shock, and the serum concentration of BUN and albumin. All parameters were compared between survived and dead group. Results : Male to female ratio was 2.07 : 1. The mean age was $63.1{\pm}17.5$years(range 25~90years) with 65% of patients aged equal to or more than 60. The major underlying diseases were old pulmonary tuberculosis(12.5%), chronic obstructive pulmonary disease(7.5%), bronchial asthma(5%), bronchiectasis(2.5%), and diabetes mellitus(22.5%). Microbiologic diagnosis was made in 26 out of 40 patients(65%). The most common causative organism was S. pneumoniae(17.5%, 7/40) followed by S. aureus(15.0%, 6/40), K. Pneumoniae(12.5%, 5/40), M. tuberculosis(7.5%, 3/40), H. influenzae(2.5%, 1/40), coagulase negative staphylococcus(2.5%, 1/40), P. aeruginosa(2.5%. 1/40), E. cloaceae(2.5%, 1/40), and E. coli(2.5%, 1/40). M. pneumoniae was detected in no patient. The most frequent drugs administered in single or combination therapy were aminoglycosides(75%, 30/40), second- and third-generation cephalosporin(40%, 16/40 and 27.5%, 11/40), macrolides(27.5%, 11/40), and amoxicillin/clavulanic acid(22.5%, 9/40). Of the 40 patients, 14 died of severe community-acquired pneumonia(37.5%). Among them, seven patients (50%) expired within 72h of hospital arrival. According to multivariate analysis, mortality was significantly associated with requirement of mechanical ventilation, bilateral pulmonary involvement, and serum albumins$\leq$3.0g/dl. Conclusion : An understanding of the clinical characteristics and prognostic factors in severe community-acquired pneumonia identified in this study will optimize therapeutic approach in this disease and help decreasing its notorious mortality rate.

• Clinical and Experimental Pediatrics
• /
• v.53 no.2
• /
• pp.178-183
• /
• 2010

Purpose : The aim of this study was to identify mutations associated with macrolide resistance in Mycoplasma pneumoniae (MP) and to establish a cultural method to determine antimicrobial susceptibility. Methods : Nasopharyngeal aspirates (NPAs) were collected from 62 children diagnosed with MP pneumonia by a serologic method or polymerase chain reaction. The 23S rRNA and L4 ribosomal protein genes of MP were amplified and sequenced. To identify mutations in these 2 genes, their nucleotide sequences were compared to those of the reference strain M129. MP cultivation was carried out for 32 (28 frozen and 5 refrigerated) NPAs and M129 strain using Chanock's glucose broth and agar plate in a 5% $CO_2$ incubator at $37^{\circ}C$ and examined at 2-3 day intervals for 6 weeks. Results : Among the 62 specimens, 17 had M144V mutations in ribosomal protein L4. The A2064G mutation was observed in 1 specimen; its 23S rRNA gene was successfully sequenced. Culture for MP was successful from the M129 strain and 2 of the 5 NPAs that were refrigerated for no longer than 3 days. However, MP did not grow from the 28 NPAs that were kept frozen at $-80^{\circ}C$ since 2003. Conclusion : We found the M144V mutation of L4 protein to be common and that of domain V of 23S rRNA gene was relatively rare among MP. Studies on the prevalence of macrolide-resistant MP and the relationship between the mutations of 23S rRNA gene and ribosomal protein L4 will aid in understanding the mechanism of macrolide resistance in MP.

• Asian-Australasian Journal of Animal Sciences
• /
• v.18 no.4
• /
• pp.590-600
• /
• 2005

The present report has been aimed at reviewing important factors which need to be closely analyzed or considered when increasing the market weight of finishing pigs. The pig market weight has increased worldwide during the past few decades, which is attributable primarily to an increased lean gain potential of finishing pigs. To increase the market weight, however, the acceptability of larger pigs by the packer as well as pork consumers should be met first. By increasing the market weight, total number of breeding stock, as well as the facility for them, necessary for producing a given weight of pork can be reduced, whereas more building space for finishing pigs and an additional nutrition program for the later finishing period are needed. Additionally, a more thorough disease prevention program especially against ileitis and mycoplasma pneumonia may also be needed, because outbreaks of these are known to increase with increasing body weight over 110 kg. Some larger finishing pigs may deposit excessive fat that may be reduced or prevented by using hormonal and/or nutritional agents. Backfat thickness increases linearly with increasing body weight between 110 and 130 kg, whereas intramuscular fat content does not change significantly. With increasing live weight within this range, the ratios of belly and loin to carcass weight also are known to increase. Some physicochemical characteristics related to fresh and cooked meat quality including color, firmness, juiciness, etc. are known to be unaffected or slightly changed following an increase of slaughter weight. In conclusion, ratios of primal cuts and pork quality characteristics are not significantly affected by increasing the market weight. Moreover, increasing the market weight of lean-type pigs approximately up to 130 kg is normally profitable to producers, as long as packers and consumers accept larger pigs.

• Korean Journal of Veterinary Research
• /
• v.44 no.4
• /
• pp.587-591
• /
• 2004

Blood samples from 622 pigs of 44 farms which were sero-positive to Mycoplasma hyopneumoniae (M. hyo) by ELISA method were collected from May 2003 to July 2004. And they were divided into 2 categories : M. hyo-vaccinated group (7 swine farms) and M. hyo-non-vaccinated group (37 swine farms). Then, each swine farm was analysed by sero-positive percentage per weeks of age. It was observed that the sero-positive percentage to M. hyo is directly proportional to weeks of age in the 44 swine farms that were selected. This meant that there has been a chronic infection of M. hyo in Korean swine herds and control of M. hyo infection did not have worked efficiently. In 7 M. hyo-vaccinated swine farms, there were no reliable patterns between sero-positive percentage to M. hyo and weeks of age. Although the swine farms have been used M. hyo vaccine, they had only little sero-positive percentage that was less than 50% at 6 to 11 weeks of age. This means a present vaccination program does not induce sufficiently a seroconversion expected. In 37 M. hyo-non-vaccinated swine farms, it was observed that sero-positive percentage was higher at above 15 weeks of age. This result showed that infection of M. hyo occurred commonly at between 7 and 12 weeks of age, at which pigs moved to the growing house. Because a risk of natural infection is severe at growing stage as well as nursery stage, it suggested that M. hyo vaccination at several weeks prior to the growing stage will give efficient effect to control the enzootic pneumonia.

• Korean Journal of Veterinary Service
• /
• v.34 no.4
• /
• pp.313-320
• /
• 2011

The purpose of this study was to investigate association with gross lesions and causative pathogens of porcine respiratory disease complex (PRDC) including porcine circovirus type 2 (PCV2), porcine reproductive and respiratory syndrome virus (PRRSV), swine influenza virus (SIV), Mycoplasma hyopneumoniae (MH), Pasteurella multocida (PM), Actinobacillus pleuropneumoniae (APP), Haemophilus parasuis (HP) in slaughtered pigs. A total of 1,200 lung samples were collected randomly from slaughtered pigs in Korea during August of 2010 through July of 2011. The gross lesions were classified according to the six stages (0, 1~10, 11~20, 21~30, 31~40 and ${\geq}41$, unit=%) and 48 samples from each stage were selected to detect viral and bacterial pathogens. The results according to the six stages were 100 (8.3%), 259 (21.6%), 326 (27.2%), 213 (17.8%), 144 (12.0%) and 158 (13.2%) cases, respectively. Prevalence of pneumonia according to season was 87.0~96.7% and the highest prevalence was in spring. In detection of pathogens by PCR, 53 samples were not detected any causative pathogens of PRDC. PCV2, PRRSV, SIV, MH, PM, APP serotype 2, APP serotype 5 and HP were positive in 45.5%, 12.5%, 10.4%, 60.1%, 1.7%, 13.9%, 12.2% and 15.6%, respectively. In co-infection, PCV2-MH was the most detected causative pathogens of PRDC. The detection rate of PCV2 and PRRSV was the highest in spring, of SIV, MH and HP was in winter. The detection rate of APP-2 and APP-5 had no seasonal prevalence. The more severe gross lesions increased, the higher the detection rate showed.