Detection of immunoglobulin M and immunoglobulin G antibodies to Mycoplasma pneumoniae in children with community-acquired lower respiratory tract infections

Context: Mycoplasma pneumoniae (M. pneumoniae) causes up to 40% of community-acquired pneumonia in children. It is impossible to identify M. pneumoniae infection on the basis of clinical signs, symptoms, and radiological features. Therefore, correct etiological diagnosis strongly depends on laboratory diagnosis. Aims: This study aims to investigate the role of M. pneumonia e in pediatric lower respiratory tract infections (LRTIs) employing enzyme-linked immunosorbent assays (ELISA) and particle agglutination (PA) test. Settings and Design: Two hundred and eighty children, age 6 months to 12 years with community-acquired LRTIs were investigated for M. pneumoniae etiology. Materials and Methods: We investigated 280 children hospitalized for community-acquired LRTIs, using ELISA and PA test for detecting M. pneumoniae immunoglobulin M (IgM) and immunoglobulin G antibodies. Statistical Analysis Used: The difference of proportion between the qualitative variables was tested using the Chi-square test and Fischer exact test. P ≤ 0.05 was considered as statistically significant. Kappa value was used to assess agreement between ELISA and PA test. Results: M. pneumoniae was positive in 51 (23.2%) <5 years and 33 (54.0%) children in ≥5 years of age group, and this difference was statistically significant (P < 0.001). Clinical and radiological findings in M. pneumoniae positive and negative groups were comparable. ELISA detected M. pneumoniae in 78 (27.8%) and PA test 39 (13.9%) patients; 33 (84.6%) ELISA positive and 6 (15.4%) ELISA negative. ELISA/PA test together detected M. pneumoniae infection in 84 (30%) children. Conclusions: Our data underline that M. pneumoniae plays an important role in children with community-acquired LRTIs and more particularly in children >5 years of age.

Clinical application and evaluation of 4 kinds of siphilis serological detection method / 国际检验医学杂志

Objective To compare the value of four kinds of commonly used serological detection method for detecting Trepone-ma Pallidum,i.e.,Treponema Pallidum enzyme-linked immunosorbent assay(TP-ELISA),Treponema pallidum particle agglutina-tion test(TPPA),Treponema Pallidum rapid plasma reagin test(RPR)and Treponema Pallidum antibody detection(TP-AD,emul-sion method).Methods 5 870 specimens from outpatients and inpatients were screened by TP-ELISA.121 cases of detected posi-tive specimen were simultaneously detected by TP-AD,TPPA and RPR.Then the detection results were performed the comparative analysis.Results Among 5 870 specimens,121 cases were positive by ELISA,the detection rate was 2.06%.Among 121 positive cases,119 cases were positive by TPPA,the conformity degree was 98.34%,49 cases were positive by RPR,the conformity degree was 40.41%,113 cases were positive by TP-AD,the conformity degree was 93.38%.With the TPPA results as the standard,there was no statistically significant difference between TPPA and TP-AD(P >0.05),but there was statistically significant difference be-tween TPPA and RPR(P <0.01).Conclusion The four kinds of method have their applicability.ELISA d has good specificity and high sensitivity,and is simple to operate and suitable for the physical examination of large amount of pregnant women,parturients and normal people.TPPA has good specificity and high accuracy,is suitable for definite diagnosis.RPR is suitable for the monito-ring and the curative effect observation in the patients with the active stage of siphilis.Compared with ELISA,TP-AD has slightly less sensitivity,but good specificity and can be used for screening without specific instrument.

Different serological tests for syphilis in 1,808 specimens / 第二军医大学学报

Objective To identify the advantages and disadvantages of the rapid plasma reagin test (RPR), chemiluminescence immunoassay (CLIA) and Treponema pallidum particle agglutination test (TPPA) for detecting syphilis. Methods A total of 1,808 serum specimens were detected by RPR and CLIA; the negative specimens as detected by CLIA and by RPR were redetected by TPPA. Results There were 170 syphilis patients among the 1,808 patients. The sensitivity and positive predictive value of RPR were both significantly lower than those of CLIA and TPPA (P0. 05). However, the negative predictive value of RPR was significantly lower than that of CLIA (P0. 05), however, the positive predictive value of CLIA was significantly lower than that of TPPA (P<0. 05). Biologically false positive results could be found for all the 3 methods and false negative results could be found for RPR and TPPA (P<0. 05). Conclusion CLIA and TPPA are superior to RPR in diagnosing syphilis. The procedure of diagnosing syphilis may need to be adjusted, and syphilis should be diagnosed by combining the medical history, symptom and lab results.

A Case of Acute Myopericarditis Associated with Mycoplasma pneumoniae Infection in a Korean Adult / 감염과화학요법

We report on a 45-year-old man with a confirmed diagnosis of acute myopericarditis associated with Mycoplasma pneumoniae. He visited our emergency department due to high fever (39degrees C) via a primary clinic. We made a diagnosis of myopericarditis based on symptoms, cardiac enzymes, electrocardiography, and transthoracic echocardiography. Serology (particle agglutination) testing for M. pneumoniae IgG antibody was also performed. The IgG antibody titer was 1:80 on the second day of admission, and increased to 1:2,560 by the 12th day of admission. Therefore, we confirmed the diagnosis of acute myopericarditis associated with M. pneumoniae and subsequently treated him with azithromycin. The symptoms and laboratory findings improved, and he recovered uneventfully.

A Case of Acute Myopericarditis Associated with Mycoplasma pneumoniae Infection in a Korean Adult / 감염과화학요법

We report on a 45-year-old man with a confirmed diagnosis of acute myopericarditis associated with Mycoplasma pneumoniae. He visited our emergency department due to high fever (39degrees C) via a primary clinic. We made a diagnosis of myopericarditis based on symptoms, cardiac enzymes, electrocardiography, and transthoracic echocardiography. Serology (particle agglutination) testing for M. pneumoniae IgG antibody was also performed. The IgG antibody titer was 1:80 on the second day of admission, and increased to 1:2,560 by the 12th day of admission. Therefore, we confirmed the diagnosis of acute myopericarditis associated with M. pneumoniae and subsequently treated him with azithromycin. The symptoms and laboratory findings improved, and he recovered uneventfully.

Mycoplasma pneumoniae: An unrecognized cause of pyrexia of unknown origin.

Objective To find out the incidence of Mycoplasma pneumoniae infection in patients with pyrexia of unknown origin. Design Prospective study. Setting University Paediatric Unit, Teaching Hospital, Karapitiya. Method Patients presenting with fever of more than 7 days with no obvious reason for its occurrence (PUO) to University Paediatric Unit, Teaching Hospital, Karapitiya from January to November 2003, were included. Patients with features of lower or upper respiratory tract infections, urinary tract infections, hepatitis, meningitis, myositis and arthritis were excluded. Routine tests for continuous fever viz. full blood count, test for malaria parasites, ESR, urine full report, urine culture, blood picture, SAT, chest x-ray, Paul-Bunnel test, hepatic transaminases and blood cultures were done in all patients. Mycoplasma antibody titre was done in each patient using the particle agglutination test. Results There were 40 patients. Age distribution was 2-12 years. 10 patients had mycoplasma pneumoniae infection, mycoplasma antibody titres ranging from 640-20,480. Conclusion 10 out of 40 (25%) children with PUO were due to mycoplasma pneumoniae infection.

Antibodies to human T-cell lymphotropic virus type I (HTLV-I) by particle agglutination (PA) test in Korean blood donors

HTLV-I infection is a recently recognized disease entity that is common in some tropical and subtropical areas, including the southwestern district of Japan. Despite the geographical proximity and frequent cultural exchanges between Korea and Japan, it is understood that Korea is not an endemic area and HTLV-I-associated illnesses are very rare in Korea. This study was designed to evaluate the positive rate of anti-HTLV-I antibodies in Korean blood donors and its regional distribution. Sera were obtained from blood donors from various districts around Korea. Anti-HTLV-I antibodies were detected by using the microtiter particle agglutination test employing an indirect agglutination technique. A total of 9,281 donors were tested and 12 donors (0.13%) were positive for anti-HTLV-I antibodies, 10 (0.11%) out of 8,845 males and 2 (0.46%) out of 436 females, with relative female predominance. A relatively high incidence of anti-HTLV-I positive donors was observed in Cheju Island (0.80%), Kyungnam (0.31%), and Chonnam (0.15%). In conclusion, the positive rate of anti-HTLV-I antibodies seemed to be very low in Korea, but the highest positive rate of anti-HTLV-I antibodies was noticed on Cheju Island, warranting further research for confirmation.

Study of Seroprevalence of Antimycoplasma Antibody in Healthy Children and its Diagnostic Value

PURPOSE: To evaluate the diagnostic reliability of the single serum titers of the specific serum antibody determiantion method, we compared antimycoplasma antibody titers of 177 healthy children with 353 children who had respiratory symptoms indicative of Mycoplasma pneumoniae infection. METHODS: We used Serodia-Myco II particle agglutination test and the titers of > or = 1:40 were regarded as positive. RESULTS: Age distribution of 177 healthy children was between 4-17 years and among these children there were 105 males and 75 females. Age distribution of 353 children with respiratory symptoms was between 2-17 years and consisted of 187 males and 166 female children. The results of antimycoplasma antibody titers of healthy 177 children were 95 cases (53.7%) of negative AMA, 30 cases (16.9%) of 1:40, 27 cases (15.3%) of 1:80, 19 cases (10.7%) of 1:160, 6 cases (3.4%) of 1:320 and there were no cases of > or = 1:640. The results of antimycoplasma antibody titers of 353 children with respiratory symptoms were 195 cases (55.2%) of negative antimycoplasma antibody 19 cases (5.4%) of 1:40, 28 cases (7.9%) of 1:80, 30 cases (8.5%) of 1:160, 33 cases (9.3%) of 1:320, and there were a total of 48 cases (13.6%) that were > or = 1:640. In healthy children the antimycoplasma antibody titers above 1:40 were 14% at 4 years of age, 7% at 5 years, 40% at 6 years and leveled out until 16 years of age. CONCLUSION: Antimycoplasma antibody titer distribution in healthy children ranged from negative to 1:320, therefore, if the single serum sample titer is < or = 1:320, for a definitive diagnosis it is necessary to compare antibody levels after 2-3 weeks.

The Seroepidemiologic Study for Human T-cell Lymphotropic Virus Type I(HTLV-I) Infection in Residents of Cheju-Do / 감염

BACKGROUND: Human T-cell lymphotropic virus type I (HTLV-I) is a retrovirus that has been identified as a cause of adult T-cell leukemia/lymphoma and tropical spastic paraparesis. HTLV-I infection is highly endemic in the southwestern islands of Japan, Caribbean basin, South America, and Africa. In 1993, we showed that the seroprevalence of antibodies to HTLV-I was 0.13% among blood donors in Korea, but surprisingly, 0.80% in Cheju-Do adjacent to endemic areas of Japan. So this study was designed to reevaluate the seroprevalence of antibodies to HTLV-I among residents in Cheju-Do. METHODS: Total 2,372 residents in Cheju-Do were tested from December 1995 to March 1996. Anti-HTLV-I antibodies were detected by the microtiter particle agglutination test. RESULTS: Among total 2,372 residents, 19 were anti-HTLV-I positive. So the overall positive rate of anti-HTLV-I antibodies was 0.80%. The positive rate in females was higher than in males (0.82% vs 0.78%). The positive rate was 1.45% in the age group of 20-29 years, 1.41% in 40-49 years, 0.91% in 0-9 years, 0.70% in 30-39 years, and 0.54% in 50-59 years. The mean age of seropositive cases is 35.2 in males and 35.4 in females, with a mean of 35.3. Geographically, high positive rate was observed in Sogwipo-City (1.37%) and Namcheju-Gun (0.83%) compared to those of Pukcheju-Gun (0.64%) and Cheju-City (0.61%), which showed high seroprevalence in districts adjacent to endemic areas of Japan. Any specific risk factors or associated disorders of HTLV-I infection could not be found among the seropositive cases. CONCLUSION: The seroprevalence of antibodies to HTLV-I in Cheju-Do was noted to be very high by the microtiter particle agglutination test. So henceforth serosurvey by confirmative laboratory tests is needed, and if high seroprevalence is showed from it, screening of blood donors for HTLV-I in Cheju-Do should be considered to prevent transfusion-associated HTLV-I infection.