Seroreactivity to Q Fever Among Slaughterhouse Workers in South Korea / 예방의학회지

OBJECTIVES: Q fever is a zoonotic disease that occurs worldwide; however, little is known about its prevalence in South Korea. We attempted to determine the prevalence of Q fever seroreactivity among Korean slaughterhouse workers and the risk factors for seroreactivity according to the type of work. METHODS: The study was conducted among 1503 workers at a total of 73 slaughterhouses and 62 residual-product disposal plants. During the study period, sites were visited and surveys were administered to employees involved in slaughterhouse work, and serological tests were performed on blood samples by indirect immunofluorescence assays. Serological samples were grouped by job classification into those of slaughter workers, residual-product handlers, inspectors and inspection assistants, and grading testers and testing assistants. Employee risk factors were analyzed according to the type of work. RESULTS: Out of 1481 study subjects who provided a blood sample, 151 (10.2%) showed reactive antibodies. When these results were analyzed in accordance with the type of work, the result of slaughter workers (11.3%) was similar to the result of residual-product handlers (11.4%), and the result of inspectors and assistants (5.3%) was similar to the result of grading testers and assistants (5.4%). Among those who answered in the affirmative to the survey question, “Has there been frequent contact between cattle blood and your mouth while working?” the proportions were 13.4 and 4.6%, respectively, and this was identified as a risk factor that significantly varied between job categories among slaughterhouse workers. CONCLUSIONS: This study found a Q fever seroreactivity rate of 10.2% for slaughterhouse workers, who are known to be a high-risk population. Contact with cattle blood around the mouth while working was the differential risk factor between job categories among slaughterhouse workers.

Prevalence of Clonorchis sinensis Metacercariae in Fish from Water Systems of Seomjin-gang (River)

The prevalence of Clonorchis sinensis metacercariae (CsMc) was examined in freshwater fish from the water systems of Seomjin-gang (River), the Republic of Korea. Total 1,604 fish from 7 local sites of Seomjin-gang were examined by artificial digestion methods. The metacercariae of C. sinensis were detected in 102 (39.8%) out of 256 fish (14 species) from the upper reaches of Seomjin-gang, i.e., Osucheon (22.3% in 6 fish species) in Imsil-gun, and Seomjin-gang (63.9% in 9 fish species) in Sunchang-gun, Jeollabuk-do. Their average density was 9.0 per infected fish. They were also found in 132 (48.0%) out of 275 fish (12 spp.) from the middle reaches of Seomjin-gang, i.e., Songdaecheon (58.9% in 4 fish species) in Namwon-si, Jeollabuk-do, and Seomjin-gang (45.2% in 10 fish species) in Gokseong-gun, Jeollanam-do. Their average density was 21.0 per infected fish. CsMc were detected in 77 (56.6%) out of 136 fish (11 species) from the lower reaches of Seomjin-gang, i.e., Seomjin-gang (73.3% in 11 fish species) in Gurye-gun, Jeollanam-do, and Namsancheon (8.6% in 1 fish species) in Hadong-gun, Gyeongsangnam-do. Their average density was 64.9 per infected fish. The metacercariae of Metorchis orientalis were also detected in 6 fish species from 4 sites of Seomjin-gang. Conclusively, it has been confirmed that CsMc are more or less prevalent in fish from some water systems of Seomjin-gang in Korea.

Intestinal Parasite Infections among Inhabitants in Yanbian Prefecture, Jilin Province, China

To investigate the prevalence of intestinal parasite infections in Yanbian Prefecture, Jilin Province, China, epidemiological surveys were conducted on a collaboration basis between the Korean Centers for Disease Control and Prevention and the Yanbian Center for Disease Control and Prevention. A total of 8,396 (males 3,737 and females 4,659) stool samples were collected from 8 localities and examined with the formalin-ether sedimentation technique, and additionally examined with the cellotape anal swab to detect Enterobius vermicularis eggs. The overall rate of intestinal parasites was 1.57%. The prevalence of Ascaris lumbricoides was the highest (0.80%), followed by Entamoeba spp. (0.23%), heterophyid flukes (0.15%), Clonorchis sinensis (0.08%), Enterobius vermicularis (0.07%), hookworms (0.06%), Trichostrongylus spp. (0.06%), Giardia lamblia (0.04%), Paragonimus spp. (0.02%), Diphyllobothrium spp. (0.02%), Trichuris trichiura (0.02%). The prevalence by sex was similar, 1.58% (n=59) in males and 1.57% (n=73) in females. By the present study, it is partly revealed that the prevalences of intestinal parasite infections are relatively low among the inhabitants of Yanbian Prefecture, Jilin Province, China.

Prevalence of Clonorchis sinensis Infection among Residents along 5 Major Rivers in the Republic of Korea

Clonorchis sinensis is currently the most important parasite affecting public health problems in the Republic of Korea. We investigated the prevalence of C. sinensis infection among residents living along 5 major rivers in Korea. A total of 42,562 individual stool samples were collected from 37 localities and examined using the formalin-ether sedimentation technique. Helminth eggs were detected in 4,052 (9.5%) residents and 3,586 (8.4%) were infected with C. sinensis. The egg positive rate of C. sinensis in Nakdong, Seomjin, Geum, Yeongsan, and Han River was 11.7%, 9.9%, 6.5%, 3.1%, and 1.0%, respectively. The overall prevalence of clonorchiasis by sex was 11.2% in males and 6.2% in females. The age-prevalence was the highest in the 50-59 years band. It has been reconfirmed that the endemicity of clonorchiasis is higher in southern areas of Korea, especially along Nakdong and Seomjin Rivers. A combination of continuous control programs with health education initiatives is urgently required in these highly endemic areas of clonorchiasis in Korea.

Pygidiopsis summa (Digenea: Heterophyidae): Status of Metacercarial Infection in Mullets from Coastal Areas in the Republic of Korea

To know the infection status of zoonotic trematode metacercariae in brackish water fish, we surveyed mullets collected from 18 coastal areas in the Republic of Korea. The metacercariae of Pygidiopsis summa were detected in 236 (68.2%) out of 346 mullets examined. They were found in mullets from 15 areas except for those from Boseong-gun (Jeollanam-do), Pohang-si, and Uljin-gun (Gyeongsangbuk-do). Especially in mullets from Taean-gun (Chungcheongnam-do) and Geoje-si (Gyeongsangnam-do), their prevalences were 100% and 95.5%, and the average metacercarial density was more than 1,000 per fish. They were also detected in mullets from 3 coastal lakes, Gyeongpoho, Songjiho, and Hwajinpoho, in Gangwon-do, and their average densities were 419, 147, and 672 per infected fish, respectively. The metacercariae of 5 other heterophyid species, including Heterophyes nocens, Heterophyopsis continua, Metagonimus sp., Stictodora fuscata, and Stictodora lari, were found in the mullets examined. The metacercariae of H. nocens were detected in 66.7, 100, 28.6, 81.6, 3.9, 61.5, and 27.3% of mullets from Muan-gun, Shinan-gun, Haenam-gun, Gangjin-gun, and Boseong-gun (Jeollanam-do), Hadong-gun, and Geoje-si (Gyeongsangnam-do), and their metacercarial intensities were 64, 84, 119, 99, 1, 24, and 24 per fish infected, respectively. From the above results, it has been confirmed that P. summa metacercariae are heavily infected in mullets from coastal areas of Korea. It is suggested that residents who frequently consume raw mullet dish can be easily infected with heterophyid flukes.

Seroprevalence and Risk Factors of Brucellosis among Slaughterhouse Workers in Korea / 예방의학회지

OBJECTIVES: The incidence of zoonoses in Korea has increased recently. However, the study of high risk groups for zoonoses has not been conducted to date in Korea. Thus, we did this study to obtain data on brucellosis among slaughterhouse workers in Korea. METHODS: We evaluated the structure of slaughterhouses and the process of slaughtering by reviewing the relevant literature and doing field studies. We visited 73 slaughterhouses and 62 residual products handle houses across the country. In addition, we conducted a questionnaire survey of the work activities, and obtained blood samples in order to determine the seroprevalence and risk factors of brucellosis. The titers of brucellosis antibodies were measured using the standard tube agglutination test (SAT). We diagnosed subjects as seropositive for Brucellosis if the titers were more than 1:160. The data collected was evaluated using SPSS ver. 17.0. RESULTS: We included 1,503 subjects and obtained 1,482 blood samples among them: 849 workers involved in slaughtering, 351 handlers of residual products, 190 inspectors and their assistants, and 92 grading testers and their assistants. The seroprevalence of brucellosis among the slaughterhouse workers was 0.8% (95% CI=0.4-1.5). Broken down, the seroprevalence of brucellosis among the workers involved in slaughtering was 0.7% (95% CI=0.3-1.6), the handlers of residual products was 1.7% (95% CI=0.7-3.9) respectively. Risk factors for contracting brucellosis among slaughterhouse workers were being splashed with cattle blood around the mouth, cattle secretions around the body and not putting on protective apron while at work. CONCLUSIONS: An educational program is needed for high risk groups on zoonoses about the prevention of infection. Thus, effective working guidelines for workers who participate in the slaughter of animals must be developed in order to protect them from zoonoses.

Two Cases of Q Fever Endocarditis / 감염과화학요법

Q fever is a zoonosis caused by Coxiella burnetii, presenting as acute and chronic illness and it has been reported worldwide. Acute Q fever is usually asymptomatic or mild and self-limiting, but infective endocarditis is one of the most serious complications of chronic Q fever and can be fatal. Known risk factors for Q fever endocarditis are valvular heart disease, immunocompromised hosts, and pregnancy. There have been some reports on Q fever in Korea but there exists no report on Q fever endocarditis. We have experienced 2 cases of Q fever with underlying valvular heart disease; both patients came to the hospital for evaluation of prolonged fever. Although Q fever and Q fever endocarditis are rare in Korea, Q fever endocarditis should be considered in the differential diagnosis of patient with infective endocarditis when causative microorganism cannot be identified.

Two Cases of Q Fever Endocarditis / 감염과화학요법

Q fever is a zoonosis caused by Coxiella burnetii, presenting as acute and chronic illness and it has been reported worldwide. Acute Q fever is usually asymptomatic or mild and self-limiting, but infective endocarditis is one of the most serious complications of chronic Q fever and can be fatal. Known risk factors for Q fever endocarditis are valvular heart disease, immunocompromised hosts, and pregnancy. There have been some reports on Q fever in Korea but there exists no report on Q fever endocarditis. We have experienced 2 cases of Q fever with underlying valvular heart disease; both patients came to the hospital for evaluation of prolonged fever. Although Q fever and Q fever endocarditis are rare in Korea, Q fever endocarditis should be considered in the differential diagnosis of patient with infective endocarditis when causative microorganism cannot be identified.

Q fever as a cause of fever of unknown origin / 대한내과학회지

Q fever is an orthozoonotic infection caused by Coxiella burnetii, which was recently reclassified from the order Rickettsials to the order Legionellales. Although Q fever is usually mild and self-limiting, it may be manifested as a serious disease, such as pneumonia, endocarditis, or meningoencephalitis. We describe three separate cases of acute Q fever, which were diagnosed by an indirect micro-immunofluorescence assay (MIFA) test and DNA amplification (PCR). Three adult patients were admitted between December 2004 and August 2006 because of a fever of greater than three weeks duration. Only one patient had contact history with a dog. Of the three patients, two patients had myalgia, headache, skin rash, lymphadenopathy, and hepatosplenomegaly. Although all sets of blood cultures were negative, anti-phase II antibody titers by using an indirect MIFA (IgG 1:512 - 1,024 and IgM 1:320) were markedly increased in sera from all of three patients. Concomitant PCR assays also demonstrated the presence of OMP com1 for C. burnetii in blood from all of the three patients. Two patients had complete resolution of symptoms and signs with a two week course of doxycycline, while one patient had spontaneous defervescence. Although the incidence of Q fever is not well known yet in Korea, it should be considered in the differential diagnosis of patients with fever of unknown origin.

Cytokine response in Balb/c mice infected with Francisella tularensis LVS and the Pohang isolate

We investigated the immune response induced by the Francisella (F.) tularensis live vaccine strain (LVS) and the Pohang isolate. After the Balb/c mice were infected intradermally (i.d) with 2 x 10(4) cfu of F. tularensis LVS and Pohang, respectively, their blood and organs were collected at different times; 0, 3, 6, 24, 72, 96, 120 and 168 h after infection. Using these samples, RT-PCR and ELISA analysis were carried out for the comparative study of the cytokines, including TNF-alpha, INF-gamma, IL-2, IL-4, IL-10 and IL-12. In the Pohang-infected mice at 120 h, the liver showed a 53 times higher level of TNF-alpha and a 42 times higher level of IFN-gamma than the respective levels at the early time points after infection. The levels of TNF-alpha and IFN-gamma induced by LVS were 5 times lower than those induced by the Pohang isolate. Also, the organs from the Pohang-infected mice showed higher levels of TNF-alpha, IFN-gamma, IL-10 and IL-12 than the levels in the LVS-infected mice. The blood from the Pohang-infected mice at 120 h revealed about a 40 times increased level of IFN-gamma, and IL-10 was also increased by 4 times at 96 h compared to an early infection time point, while IL-4 was not induced during the whole infection period. These results suggest that F. tularensis may induce a Th1-mediated immune response to in vivo infection and the Pohang isolate has a higher capacity than the LVS to induce an acute immune response in Blab/c mice.

Seroprevalence of Brucellosis among Risk Population in Gyeongsangbuk-do, 2006 / 예방의학회지

OBJECTIVES: Cases of human brucellosis in Korea have recently increased due to the increasing incidence of bovine brucellosis. The authors conducted this study to elucidate the status of brucellosis through seroepidemiologic study. METHODS: We selected our study population from a high risk group. We conducted a questionnaire survey and obtained blood samples to determine the seroprevalence of brucellosis antibodies for 10 days in February, 2005. The titers of brucellosis were measured by the combination of standard tube agglutination test (STA) and enzyme-linked immunosorbent assay (ELISA) test. RESULTS: Our study subjects comprised 1,075 cases: 971 livestock workers, 51 veterinarians, and 53 artificial inseminators. In the STA test, 27 cases (2.5%) had titers of greater than or equal to 1:20. Of 1,068 cases (7 cases were excluded due to previous brucellosis), 7 cases of brucellosis were diagnosed with titers of 1:160, giving a seroprevalence of brucellosis of 0.66%. The seroprevalence in the male group was 0.95%, and that of livestock workers, veterinarians, and artificial inseminators was 0.52%, 4.17%, and 0.00%, respectively. The Spearman's correlation coefficient between the positive rate of bovine brucellosis per capita and household and human brucellosis was 0.806 and 0.744, respectively. The concordance rate between the Korea National Institute of Health and the Gyeongsangbuk-do Institute of Health and Environment by the STA and ELISA tests was 94.7% and 100.0%, respectively. CONCLUSIONS: The study results indicated in higher seroprevalence rate among veterinarians than among livestock workers and artificial inseminators. Because veterinarians may be exposed to this high risk, effective working guidelines for veterinarians to guard against brucellosis must be developed. Moreover, more extensive epidemiologic research for laboratory workers and meat handlers is needed.

Spontaneous Bacterial Peritonitis due to Brucella abortus in a Cirrhotic Patient in Jeju Island / 감염과화학요법

Spontaneous bacterial peritonitis is the common infectious disease in liver cirrhosis patients with a fever. Brucellosis is a rare cause of bacterial peritonitis. A case indigenous to a citizen of Jeju, he ate a raw veal of cow four times in last 2 months prior to admission. The gram-negative bacilli were isolated from blood and peritoneal fluid cultures. He was confirmed brucellosis by serologic work- ups. This isolate was confirmed as Brucella abortus by using PCR amplification of 16S ribosomal RNA (rRNA) and omp2. This is the first case of bruellosis that was diagnosed spontaneous bacterial peritonitis in liver cirrhosis patient among native korean citizens. Successful treatment was obtained by using a regimen of doxycycline and gentamicin. Brucella should be suspected as a cause of spontaneous bacterial peritonitis in cirrhotic patients with no response to standard spontaneous bacterial peritonitis treatments.

Spontaneous Bacterial Peritonitis due to Brucella abortus in a Cirrhotic Patient in Jeju Island / 감염과화학요법

Spontaneous bacterial peritonitis is the common infectious disease in liver cirrhosis patients with a fever. Brucellosis is a rare cause of bacterial peritonitis. A case indigenous to a citizen of Jeju, he ate a raw veal of cow four times in last 2 months prior to admission. The gram-negative bacilli were isolated from blood and peritoneal fluid cultures. He was confirmed brucellosis by serologic work- ups. This isolate was confirmed as Brucella abortus by using PCR amplification of 16S ribosomal RNA (rRNA) and omp2. This is the first case of bruellosis that was diagnosed spontaneous bacterial peritonitis in liver cirrhosis patient among native korean citizens. Successful treatment was obtained by using a regimen of doxycycline and gentamicin. Brucella should be suspected as a cause of spontaneous bacterial peritonitis in cirrhotic patients with no response to standard spontaneous bacterial peritonitis treatments.

Mycoplasma pneumoniae-induced production of proasthmatic mediators in airway epithelium / 소아과

PURPOSE: There has been an increasing amount of literature concerning the association between Mycoplasma pneumoniae and asthma pathogenesis. Interleukin(IL)-6 stimulates the differentiation of monocytes, and can promote Th2 differentiation and simultaneously inhibit Th1 polarization. IL-8 is a potent chemoattractant and, it has been suggested, has a role in asthma pathogenesis. Nitric oxide (NO) synthesized by airway epithelium may be important in the regulation of airway inflammation and reactivity. Vascular endothelial growth factor(VEGF) has been reported to be a mediator of airway remodeling in asthma. We investigated the effects of M. pneumoniae on IL-6, IL-8, NO and VEGF production in human respiratory epithelial cells. METHODS: A549 cells were cultured and inoculated with M. pneumoniae at a dose of 20 cfu/cell. After infection, the presence of M. pneumoniae in epithelial cell cultures was monitored by immunofluorescence and confirmed by polymerase chain reaction(PCR) detection. IL-6, IL-8 and VEGF were determined by an enzyme-linked immunosorbent assay and reverse transcriptase-polymerase chain reaction. NO was measured using the standard Griess reaction. RESULTS: In A549 cells, M. pneumoniaeinduced IL-6, IL-8, NO and VEGF release in time-dependent manners. It also induced mRNA expression of IL-6, IL-8 and VEGF in similar manners. CONCLUSION: These observations suggest that M. pneumoniae might have a role in the pathogenesis of the allergic inflammation of bronchial asthma.

Identification of Brucella abortus using the sequencing of omp gene / 대한내과학회지

BACKGROUND: As the incidence of bovine brucellosis increases in Korea, the incidence of human brucellosis is also increasing since 2002. However, it is difficult to identify Brucella species by using the conventional methods. METHODS: Three strains of gram-negative coccobacilli were isolated from blood specimens of three patients with prolonged fever, which were not identified by using the conventional methods. After extracting total DNA from these isolates, PCR amplification of 16S rRNA and omp2 genes was performed. These sequences secured by PCR assay were compared with known sequences by using GenBank BLAST. RESULTS: DNA sequences were obtained from 3 isolates by using PCR amplification of 16S rRNA. These sequences had more than 99.9% similarities with Brucella species by using GenBank BLAST. In the second place, after comparing DNA sequences secured by PCR amplification of omp2a and omp2b by using GenBank BLAST, these isolates were confirmed as B. abortus. CONCLUSIONS: DNA sequence analysis is a rapid and accurate method for identification of uncommon microorganisms, such as Brucella species.

Usefulness of Nested PCR for Diagnosis of Scrub Typhus in Clinical Practice: Prospective study / 감염과화학요법

BACKGROUND: Laboratory studies as diagnostic tools of scrub typhus have shown PCR to be sensitive and specific, but there have been few clinical studies. The aims of this study were to determine the diagnostic accuracy and clinical usefulness of the nested PCR through a prospective comparison of the nested PCR and indirect immunofluorescence assay (IFA). MATERIALS AND METHODS: We conducted a multicenter prospective study of patients with possible scrub typhus. Adult patients who have had fever together with eschar or a maculopapular skin rash and more or equal to two of the following symptoms: headache, malaise, myalgia, coughing, nausea, and abdominal discomfort were enrolled. Each patient was admitted between September, 2004 and December, 2004 to Chosun University Hospital and one of its three community branch hospitals (Haenam General Hospital, Jangheung Hospital, Muan Hospital), which are all located in the southwest of Korea. Whole blood samples were collected for PCR testing and sera were obtained for serology evaluation using the IFA and passive hemagglutination assay (PHA). RESULTS: We enrolled 135 possible scrub typhus patients, and 118 scrub typhus patients were confirmed on the basis of either a single indirect immunofluorescent specific IgM titer against O. tsutsugamushi of > or =1:10 or 4-fold or greater rise in IFA follow up titer. One hundred eighteen patients were confirmed as scrub typhus, 7 patients were undetermined and 10 patients were confirmed as the other diseases. The result of nested PCR assay demonstrated a sensitivity of 82.2% (95% confidence interval 0.74-0.88), a specificity of 100% (95% confidence interval 0.66-1), positive predictive value of 1 (95% confidence interval 0.95-1) and negative predictive value of 0.32 (95% confidence interval 0.17-0.51). 96 patients out of 118 patients were positive for IgM on the admission day. Of 22 patients with negative for IgM antibody at admission, 19 had positive results for nested PCR using buffy coat. CONCLUSION: The nested PCR assay of buffy coat is useful for rapid and reliable test for confirmation of the diagnosis of scrub typhus.

Clinical Characteristics of Human Brucellosis in South Korea / 감염과화학요법

BACKGROUND: Since the first Korean case of human brucellosis was reported in 2002, the incidence of human brucellosis has been rapidly increasing. We performed this study to evaluate the clinical characteristics of human brucellosis occurring in South Korea. MATERIALS AND METHODS: Demographic features, clinical manifestations, and therapeutic outcomes of cases confirmed as brucellosis according to WHO diagnostic criteria were evaluated. Species of Brucella isolates were identified with 16S rRNA gene sequencing method. Serologic diagnosis was performed with standard tube agglutination test (STA). RESULTS: A total of 34 cases were enrolled from 2003 to 2006 in six hospitals. Eight cases were confirmed with the isolation of Brucella from blood and 26 cases were confirmed with titer of antibodies < or =1:160 by STA. Male (31) was predominant and most of the patients were cattle farmers. The most common transmission route was direct contact with infected or their cattle byproducts. Fever was the most prominent symptom and fatigue followed. Gastrointestinal and musculoskeletal systems were commonly complicated. Patients were treated with doxycycline and rifampin or aminoglycosides for more than 6 weeks. All patients responded well to the therapeutic regimens, but one patient relapsed 10 months after treatment. CONCLUSION: Brucellosis occurring in Korea has been caused by B. abortus, whose preferred natural host animals are cattle. Korean patients were infected through direct contact with bovine brucellosis. Clinical manifestations of brucellosis were similar to those occurring worldwide. Therapeutic outcomes were good among patients with brucellosis in Korea. In order to prevent human brucellosis, measures to eradicate bovine brucellosis should precede.

Usefulness of Nested PCR for Diagnosis of Scrub Typhus in Clinical Practice: Prospective study / 감염과화학요법

BACKGROUND: Laboratory studies as diagnostic tools of scrub typhus have shown PCR to be sensitive and specific, but there have been few clinical studies. The aims of this study were to determine the diagnostic accuracy and clinical usefulness of the nested PCR through a prospective comparison of the nested PCR and indirect immunofluorescence assay (IFA). MATERIALS AND METHODS: We conducted a multicenter prospective study of patients with possible scrub typhus. Adult patients who have had fever together with eschar or a maculopapular skin rash and more or equal to two of the following symptoms: headache, malaise, myalgia, coughing, nausea, and abdominal discomfort were enrolled. Each patient was admitted between September, 2004 and December, 2004 to Chosun University Hospital and one of its three community branch hospitals (Haenam General Hospital, Jangheung Hospital, Muan Hospital), which are all located in the southwest of Korea. Whole blood samples were collected for PCR testing and sera were obtained for serology evaluation using the IFA and passive hemagglutination assay (PHA). RESULTS: We enrolled 135 possible scrub typhus patients, and 118 scrub typhus patients were confirmed on the basis of either a single indirect immunofluorescent specific IgM titer against O. tsutsugamushi of > or =1:10 or 4-fold or greater rise in IFA follow up titer. One hundred eighteen patients were confirmed as scrub typhus, 7 patients were undetermined and 10 patients were confirmed as the other diseases. The result of nested PCR assay demonstrated a sensitivity of 82.2% (95% confidence interval 0.74-0.88), a specificity of 100% (95% confidence interval 0.66-1), positive predictive value of 1 (95% confidence interval 0.95-1) and negative predictive value of 0.32 (95% confidence interval 0.17-0.51). 96 patients out of 118 patients were positive for IgM on the admission day. Of 22 patients with negative for IgM antibody at admission, 19 had positive results for nested PCR using buffy coat. CONCLUSION: The nested PCR assay of buffy coat is useful for rapid and reliable test for confirmation of the diagnosis of scrub typhus.

Clinical Characteristics of Human Brucellosis in South Korea / 감염과화학요법

BACKGROUND: Since the first Korean case of human brucellosis was reported in 2002, the incidence of human brucellosis has been rapidly increasing. We performed this study to evaluate the clinical characteristics of human brucellosis occurring in South Korea. MATERIALS AND METHODS: Demographic features, clinical manifestations, and therapeutic outcomes of cases confirmed as brucellosis according to WHO diagnostic criteria were evaluated. Species of Brucella isolates were identified with 16S rRNA gene sequencing method. Serologic diagnosis was performed with standard tube agglutination test (STA). RESULTS: A total of 34 cases were enrolled from 2003 to 2006 in six hospitals. Eight cases were confirmed with the isolation of Brucella from blood and 26 cases were confirmed with titer of antibodies < or =1:160 by STA. Male (31) was predominant and most of the patients were cattle farmers. The most common transmission route was direct contact with infected or their cattle byproducts. Fever was the most prominent symptom and fatigue followed. Gastrointestinal and musculoskeletal systems were commonly complicated. Patients were treated with doxycycline and rifampin or aminoglycosides for more than 6 weeks. All patients responded well to the therapeutic regimens, but one patient relapsed 10 months after treatment. CONCLUSION: Brucellosis occurring in Korea has been caused by B. abortus, whose preferred natural host animals are cattle. Korean patients were infected through direct contact with bovine brucellosis. Clinical manifestations of brucellosis were similar to those occurring worldwide. Therapeutic outcomes were good among patients with brucellosis in Korea. In order to prevent human brucellosis, measures to eradicate bovine brucellosis should precede.

Diagnostic Availability of PCR and ELISA in Mycoplasma pneumoniae Pneumonia / 소아알레르기및호흡기학회지

PURPOSE: Mycoplasma pneumoniae is a common respiratory pathogen responsible for acute respiratory infections in young children. The standard laboratory methods for the specific diagnosis of M. pneumoniae infection have been isolation in culture and serological methods. The objective of this study was to compare the performance of enzyme-linked immunosorbent assays (ELISA) for the detection of M. pneumoniae specific IgG and IgM antibodies and polymerase chain reaction (PCR) in diagnosis of M. pneumoniae pneumonia. METHODS: For a 1-year period, 111 patients admitted to Severance Hospital and Yongdong Severance Hospital with clinical features of pneumonia and radiographically defined pneumonia were included. Serum specimens and throat swab specimens were obtained at the time of admission. Patients who showed M. pneumoniae antibody titer 1:320 or greater or a fourfold increase in M. pneumoniae antibody titer between acute and convalescent sera obtained 5 days to 3 weeks after the onset of illness were diagnosed as having M. pneumoniae pneumonia. PCR and ELISA were also performed. RESULTS: The sensitivity, specificity, false positivity, and false negativity of PCR were 40.6 percent, 63.3 percent, 69.1 percent, and 27.5 percent, respectively. The sensitivity, specificity, false positivity, and false negativity of ELISA IgM were 9.4 percent, 100 percent, 0 percent, and 26.9 percent, respectively. The sensitivity, specificity, false positivity, and false negativity of the use of PCR and ELISA in combination were 46.9 percent, 63.3 percent, 65.9 percent, and 25.4 percent, respectively. CONCLUSION: These observations suggest that the use of PCR and ELISA in addition to the detection of serum antibody to Mycoplasma pneumoniae using microparticle agglutination would allow the maximal number of diagnoses to be made at a very early phase of infection.