The value of antibody-coated bacteria in tracheal aspirates for the diagnosis of ventilator-associated pneumonia: a case-control study / Utilidade da avaliação de bactérias revestidas por anticorpos em aspirados traqueais para o diagnóstico de pneumonia associada à ventilação mecânica: um estudo caso-controle

ABSTRACT Objective: Ventilator-associated pneumonia (VAP) is the leading type of hospital-acquired infection in ICU patients. The diagnosis of VAP is challenging, mostly due to limitations of the diagnostic methods available. The aim of this study was to determine whether antibody-coated bacteria (ACB) evaluation can improve the specificity of endotracheal aspirate (EA) culture in VAP diagnosis. Methods: We conducted a diagnostic case-control study, enrolling 45 patients undergoing mechanical ventilation. Samples of EA were obtained from patients with and without VAP (cases and controls, respectively), and we assessed the number of bacteria coated with FITC-conjugated monoclonal antibodies (IgA, IgM, or IgG) or an FITC-conjugated polyvalent antibody. Using immunofluorescence microscopy, we determined the proportion of ACB among a fixed number of 80 bacteria. Results: The median proportions of ACB were significantly higher among the cases (n = 22) than among the controls (n = 23)-IgA (60.6% vs. 22.5%), IgM (42.5% vs. 12.5%), IgG (50.6% vs. 17.5%), and polyvalent (75.6% vs. 33.8%)-p < 0.001 for all. The accuracy of the best cut-off points for VAP diagnosis regarding monoclonal and polyvalent ACBs was greater than 95.0% and 93.3%, respectively. Conclusions: The numbers of ACB in EA samples were higher among cases than among controls. Our findings indicate that evaluating ACB in EA is a promising tool to improve the specificity of VAP diagnosis. The technique could be cost-effective and therefore useful in low-resource settings, with the advantages of minimizing false-positive results and avoiding overtreatment.

RESUMO Objetivo: A pneumonia associada à ventilação mecânica (PAVM) é o principal tipo de infecção adquirida no ambiente hospitalar em pacientes em UTIs. O diagnóstico de PAVM é desafiador, principalmente devido a limitações dos métodos diagnósticos disponíveis. O objetivo deste estudo foi determinar se a avaliação de bactérias revestidas por anticorpos (BRA) pode melhorar a especificidade de culturas de aspirado traqueal (AT) no diagnóstico de PAVM. Métodos: Estudo diagnóstico caso-controle envolvendo 45 pacientes sob ventilação mecânica. Amostras de AT foram obtidas de pacientes com e sem PAVM (casos e controles, respectivamente), e verificamos o número de bactérias revestidas com anticorpos monoclonais conjugados com FITC (IgA, IgM ou IgG) ou anticorpo polivalente conjugado com FITC. Utilizando microscopia de imunofluorescência, foi determinada a proporção de BRA em um número fixo de 80 bactérias. Resultados: A mediana das proporções de BRA foi significativamente maior nos casos (n = 22) que nos controles (n = 23) - IgA (60,6% vs. 22,5%), IgM (42,5% vs. 12,5%), IgG (50,6% vs. 17,5%) e polivalente (75,6% vs. 33,8%) - p < 0,001 para todos. A acurácia dos melhores pontos de corte para o diagnostico de PAVM em relação aos BRA monoclonais e polivalentes foi > 95,0% e > 93,3%, respectivamente. Conclusões: O número de BRA em amostras de AT foi maior nos casos que nos controles. Nossos achados indicam que a avaliação de BRA no AT é uma ferramenta promissora para aumentar a especificidade do diagnóstico de PAVM. A técnica pode ser custo-efetiva e, portanto, útil em locais com poucos recursos, com as vantagens de minimizar resultados falso-positivos e evitar o tratamento excessivo.

Development of an indirect ELISA to detect Corynebacterium pseudotuberculosis specific antibodies in sheep employing T1 strain culture supernatant as antigen / Desenvolvimento de ELISA indireto para detectar anticorpos específicos contra Corynebacterium pseudotuberculosis em ovinos utilizando o supernadante de cultura da cepa T1 como antígeno

Corynebacterium pseudotuberculosis is the etiologic agent of caseous lymphadenitis (CLA), a chronic disease that affects goats and sheep, characterized by granuloma formation in subcutaneous and internal lymph nodes. CLA causes significant economic losses to commercial goat herds. In this study, we aimed to test secreted antigens secreted from T1 strain bacteria grown in brain heart infusion (BHI) broth in an indirect ELISA system to determine the presence of specific immunoglobulins against C. pseudotuberculosis. We analyzed the BHI antigen electrophoretic profile and the recognition pattern by infected sheep sera samples. The ELISA results were compared with multiplex PCR assay and IFN-gamma production. The ELISA was able to discriminate between negative and positive animals, with a sensitivity of 89% and a specificity of 99%, using microbiological isolation as gold standard. When this assay was compared with multiplex PCR and specific IFN-gamma quantification, six discrepant results were found among thirty-two samples. We concluded that the ELISA using antigens secreted from C. pseudotuberculosis T1 strain growth in BHI broth culture can be used for the serodiagnosis of CLA in sheep.

Corynebacterium pseudotuberculosis é o agente etiológico da linfadenite caseosa (LC) uma doença crônica que afeta ovinos e caprinos caracterizada pela formação de granulomas em linfonodos. A LC causa perdas econômicas significativas em criações de pequenos ruminantes. Este trabalho teve como objetivo testar antígenos secretados da cepa T1 da bactéria em um sistema de ELISA indireto para detecção de anticorpos específicos contra C. pseudotuberculosis. O perfil eletroforético do antígeno foi analisado, bem como o padrão de reconhecimento por soros de animais infectados. Os resultados do ELISA foram comparados com ensaio de multiplex PCR e com teste de indução de produção específica de IFN-gama. O ELISA foi capaz de discriminar animais positivos de animais negativos, com sensibilidade de 89% e especificidade de 99%, usando o isolamento microbiológico como padrão ouro. Quando o ensaio foi comparado com o multiplex PCR e a produção específica de IFN-gama, somente seis resultados discrepantes foram encontrados em trinta e duas amostras. Pode-se concluir que o ensaio de ELISA desenvolvido pode ser utilizado com alto grau de confiança para o diagnóstico da LC em ovinos.

Mycobacterial heparin-binding haemagglutinin adhesion-induced interferon & antibody for detection of tuberculosis.

Background & objectives: Mycobacterial heparin-binding haemagglutinin adhesin (HBHA) plays an important role in humoral and cellular immune response and is a potential diagnostic tool for tuberculosis (TB) serodiagnosis. This study was carried out to assess the usefulness of HBHA in TB clinics for differential diagnosis of pulmonary and extra-pulmonary TB (PTB, EPTB). Methods: In this study, 165 outpatients and 133 healthy volunteers were included to investigate the role of HBHA in TB diagnosis including the serodiagnostic tests and the interferon-γ release assays (IGRAs). The healthy volunteers were all without BCG vaccination including 73 subjects with purified protein derivative (PPD) (-) and 60 ones with PPD (+) (that is P-B- and P+B-). Of all the 165 outpatients 77 were PTB and 88 were EPTB. HBHA protein was used for serodiagnostic tests and IGRAs in peripheral blood mononuclear cells. Results: HBHA-specific antibody levels in the serum of healthy subjects were significantly different from the patients with PTB or EPTB (P<0.05). HBHA specific antibody levels in PTB patients could differentiate from EPTB with limited sensitivity (77.08%; 95%CI, 62.69 to 87.97%) and specificity (87.50%; 95%CI, 74.75 to 95.27%). IFN-γ levels in the healthy (P+B- and P-B-) groups were significantly different (P<0.01) with a detection sensitivity of 84.8% (95%CI, 68.54 to 93.02%) and specificity of 80.7% (95%CI, 65.22 to 92.62%). The PTB and EPTB subjects showed no difference in IFN-γ production. Interpretation & conclusions: HBHA serodiagnostic test with IGRAs had the limited potential for use as auxiliary tools for the differential diagnosis of PTB and EPTB, since both methods showed low sensitivity and specificity.

Prevalência de anticorpos contra agentes virais e bacterianos em eqüídeos do município de Monte Negro, Rondônia, Amazônia ocidental brasileira / Seroprevalence of viral and bacterial agents in equids from Monte Negro municipality, State of Rondônia. brazilian western Amazon

Foram examinados 176 eqüídeos (15 muares e 161 eqüinos) do município de Monte Negro, Rondônia, Amazônia Ocidental Brasileira, frente a agentes virais e bacterianos. A amostra correspondeu ao total de eqüídeos no município, considerando um nível de confiança de 99%, prevalência esperada de 50% e erro padrão de 10%. As infecções virais foram investigadas pelas provas de Imunodifusão em gel de Agar (Anemia Infecciosa Eqüina - AIE), Inibição da hemaglutinação (Influenza eqüina tipos 1 e 2 - IE-1 e 2) e Soroneutralização em cultura celular (Arterite Viral Eqüina - AVE, Herpesvírus Eqüino tipo 1 - HVE1, Estomatite Vesicular - EV e Encefalomielite Eqüina do Leste - EEE, do Oeste - WEE e Venezuela - VEE). Para o diagnóstico da leptospirose, foi utilizada a prova de Soroaglutinação Microscópica (SAM); para o diagnóstico da brucelose, o teste do Antígeno Acidificado Tamponado (AAT) foi utilizado como teste de triagem e as provas de Soroaglutinação Lenta em Tubos (SLT) e 2- mercaptoetanol como testes diagnósticos. Foram constatados 9,6% dos eqüídeos reativos para AIE, 22,7% para HVE1, 19,9% para IE- 1, 42,0% para IE-2, 21,0% para EEE, 11,3% para VEE, 3,4% para Brucella spp. e 91,4% para Leptospira spp. Os sorovares de leptospira mais freqüentes foram Bratislava (10,5%), Icterohaemorrhagiae (8,7%) e Autumnalis (8,7%) nos eqüinos e Patoc (26,6%) nos muares. Não foram encontrados animais com anticorpos contra AVE, EV e WEE.

Sera from 174 equidaes (15 mules and 161 equines) of Monte Negro municipality, Rondônia State were analyzed against viral and bacterial agents. The serum sample corresponded the total equid population in the municipality considering a confidence interval of 99%, expected prevalence of 50% and absolute desired of 10%. For the viral agents, sera were tested by the Agar Gel Immunodiffusion Test (Equine Infection Anemia - EIA), Inhibition Haemagglutination Test (Equine Influenza 1 and 2 - EI - 1 and 2), and Virusneutralizating Tests (Equine Viral Arteritis - EVA, Equine Herpesvirus 1 - EHV1, Vesicular Stomatitis - VS, Equine Encephalitis Eastern - EEE, Western - WEE and Venezuelan VEE). The diagnosis for brucellosis was made by Agglutination Tests and the Microscopic Agglutination Test was used for leptospirosis. The results showed positivity of 9.6% for EIA, 22.7% for HVE1, 19.9% for IE-1, 42.0% for IE-2, 21.0% for EEE, 11.3% for VEE, 3.4% for brucellosis, and 91.4% for leptospirosis. The most frequent serovars detected were Bratislava (10.5%), Icterohaemorrhagiae (8.7%), Autumnalis (8.7%) for equines and Patoc (26.6%) for mules. No one of the examined samples reacted to EVA, VS, or WEE.

Whole cell ELISA for detection of Helicobacter pylori antibodies with reference to peptic ulcers

The specific objectives of this study are to compare isolation of the H. pylori from biopsies with results of a whole cell enzyme linked immunosorbent assay [ELISA] for specific antibodies in serum and saliva. One hundred and nine patients attending outpatient endoscopy clinics were randomly selected. Two biopsies were collected from each patient, one biopsy from each site was cultured and an additional biopsy was taken from the antrum for campylobacter like organism [CLO] test. Blood and saliva samples were also collected to determine specific antibodies to H. pylori using whole cell ELISA. H. pylori specific serum IgG, IgM, IgA and salivary IgA in patients were determined by whole cell ELISA. The results confirmed the diagnostic value of ELISA for determination of serum IgG antibodies against H. pylori and showed that 1/100 dilutions of serum and 1 /5 dilutions of saliva distinguished between H. pylori infected and non-infected patients which is correlated with CLO test. The results of the ELISA assay are significantly correlated with the presence of H. pylori in gastric biopsies determined with CLO test, microscopy and culture. In addition, the assay differentiated between patients with and without peptic ulcers. These results suggest that ELISA might be useful for screening patients referred for endoscopy, thereby reducing the endoscopy list in the clinic

Inmunoglobulinas en pacientes con actinomicetoma por Nocardia brasiliensis / Immunoglobulins in patients with Nocardia brasiliensis actinomycetoma

Considerando que algunos autores han reportado un aumento en la cantidad de algunas inmunoglobulinas en los pacientes con actinomicetoma, en este trabajo nos propusimos determinar diferencias en la producción de IgG1, IgG2, IgG3, IgG4 e IgM en 25 pacientes con actinomicetoma por Nocardia brasiliensis y 25 personas sanas provenientes de una zona endémica de micetoma. La determinación de inmunoglobulinas se realizó por medio de la técnica de ELISA. Para sensibilizar las placas se emplearon 6 antígenos de N. brasiliensis: un antígeno crudo denominado NB y cinco derivados del mismo (NB2, NB4, NB6, NB8 y NB10) separados por punto isoeléctrico. Los niveles de las cuatro subclases de IgG fueron mayores en los sueros de los pacientes que en el suero de los controles, con una diferencia máxima en IgG3 e IgG4; para esta última subclase, los seis antígenos fueron altamente reactivos. La concentración de IgM fue igual en ambos grupos. Es probable que como ocurre en otras infecciones, en la fisiopatogenia del actinomicetoma influya no sólo el aumento o deficiencia de una clase de inmunoglobulina, sino la relación que existe entre las diferentes subclases.

Considering that some authors have reported an increasing of some immunoglobulins in actinomycetoma patients, in this study we propose to determine differential production of IgG1, IgG2, IgG3, IgG4 and IgGM in 25 patients with actinomycetoma and 25 healthy individuals from a mycetoma endemic area. Immunoglobulins were determined by ELISA technique. To sensibilize the plates, six Nocardia brasiliensis antigens were used: a crude antigen denominated NB and five derivatives (NB2, NB4, NB6, NB8 and NB10) obtained by their isoelectric point. Results showed that all IgG subclasses were higher in the patients’ sera than in control sera, with a maximal difference to IgG3 and IgG4. To the latter subclass, six antigens were highly reactives. IgM levels were similar in both groups. As it occurs in other infections, in the actinomycetoma pathogenesis probably participate the increase or deficiency of a determined immunoglobulin class, as well as the relationship between different subclasses.

Seroprevalencia de anticuerpos anti-caga de helicobacter pylori y su relacion con factores epidemiologicos wn Santa Fe / Seroprevalence of helicobacter pylori anti-caga antibodies and its relationship with epidemiologic factors in Santa Fe

La detección precoz de anticuerpos anti-CagA en adultos jóvenes tendría gran impacto clínico en la prevención del cáncer gástrico. El objetivo del presente trabajo fue determinar en nuestra región la seroprevalencia de los anticuerpos IgG y anti-CagA de Helicobacter pylori, con una técnica no invasiva y fácil de realizar; valorando su relación con diferentes factores de riesgos epidemiológicos. Se incorporaron 435 voluntarios de diferentes centros de salud con edad promedio de 40 años. Mediante una encuesta personalizada se registraron variables demográficas, condiciones socieconómicas, entre otros datos de interés. En el suero de los individuos se determinó la presencia de anticuerpos IgG específicos y anti-CagA del Helicobacter pylori mediante una técnica de enzimoinmunoensayo. La prevalencia de los anticuerpos IgG fue de 52.2%, siendo positivo en 152 (53.7%) mujeres y 75 (49%) varones. Los anticuerpos IgG estaban presentes en el 65.0% de los individuos con síntomas y en el 44.1% de los asintomáticos. La prevalencia de los anticuerpos anti-CagA en la muestra estudiada fue 33.1%, presentándose en el 63.4% de los sujetos seropositivos (IgG), siendo positivo en 96 (33.9%) mujeres y 48 (31.6%) varones. La prevalencia fue 45.4% y 25.7% en los sintomáticos y asintomáticos respectivamente. Se demostró que los anticuerpos IgG están asociados a la edad, zona de residencia, nivel educacional y número de dormitorios por vivienda; mientras que los anticuerpos anti-CagA dependen de la zona de residencia y de la presencia de síntomas. La influencia de la variable predictiva síntomas sobre la presencia de los anticuerpos anti-CagA revelan la importancia selectiva en la corroboración de parámetros clínicos de las enfermedades gastroduodenales asociadas a Helicobacter pylori.

Role of modified Widal test in the diagnosis of enteric fever.

OBJECTIVES: To evaluate the diagnostic specificity of modified Widal for recent infection in comparison with conventional Widal test. METHOD: Modified widal test was simultaneously done along with conventional Widal test in serum samples obtained from 50 bacteriologically positive cases of Salmonella typhi infection as well as 50 healthy individuals. RESULTS: A four-fold difference in the titres was noticed in the 50 sera of the test group and no charge in the titres of the control group. The early rising O antibodies which are predominantly IgM in nature. These are due to recent infection and are inactivated by 2-mercaptoethanol. On the other hand H is a mixture of IgG and IgM hence IgM portion gets inactivated giving rise to fall in titre. By inactivating IgM antibodies in modified Widal test, the agglutination would be brought about only by specific IgG while in the conventional Widal test agglutination is due to specific IgG and IgM. The difference in the titres indicates specific IgM class of antibodies which is the hallmark of recent infection. CONCLUSION: If conventional Widal test and modified Widal test are simultaneously done, one can be definite about the diagnosis of enteric fever.

Autotransplant of spleen tissue in children with schistosomiasis: evaluation of splenic function after splenosis

Autotransplantation of spleen tissue has been done, in the past ten years, in children with schistosomiasis mansoni with bleeding varices. The purposes of this investigation were: (1) to study the morphology and function of the remnant spleen tissue; (2) to quantify the production of tuftsin; and (3) to assess the immune response to pneomococcal vaccine of these patients. Twenty three children, who underwent splenectomy and autologous implantation of spleen tissue into the greater omentum were included in this investigation. The average postoperative follow-up is five years. Splenosis was proved by colloid liver-spleen scans. Search for Howell-Jolly bodies assessed the filtration function. Tuftsin and the titer of pneumococcal antibodies were quantified by ELISA. Splenosis was evident in all children; however, it was insufficient in two. Howell-Jolly bodies were found only in these two patients. The mean tuftsin serum concentration (335.0 ± 29.8 ng/ml) was inside the normal range. The immune response to pneumococcal vaccination was adequate in 15 patients; intermediate in four; and inadequate in four. From the results the following conclusions can be drawn: splenosis was efficient in maintaining the filtration splenic function in more than 90 percent and produced tuftsin inside the range of normality. It also provided the immunologic splenic response to pneumococcal vaccination in 65 percent of the patients of this series

Soroprevalência de Anaplasma marginale em bovinos na mesorregiäo norte fluminense / Seroprevalence of Anaplasma marginale in cattle in the \"norte fluminense\" mesoregion

Avaliou-se a soroprevalência de Anaplasma marginale em bovinos de nove municípios na mesorregião Norte Fluminense do estado do Rio de Janeiro através do ensaio de imunoadsorção enzimática (ELISA) indireto. 532 amostras de soro de bovinos foram analisadas; dos quais, 497 eram fêmeas e 35 eram machos; e destes, 444 animais com aptidão zootécnica para corte e 88 com aptidão para leite. A avaliação sorológica revelou que 485 (91,16%) foram positivas, dos quais: 55,45% com título de 1:500, 22,18% com título de 1:1000, 6,77% com título de 1:2000, 3,01% com título de 1:4000, 1,50% com título de 1:8000, 0,94% com título de 1:16000, 0,75% com título de 1:32000, 0,56% com título de 1:64000 e 8,84% foram negativos. A análise da prevalência segundo a faixa etária foi realizada dividindo-se em três grupos etários: 1 a 3 anos (n= 110), 3 a 6 anos (n= 241) e > 6 anos (n= 181), onde 91,82%, 92,95% e 88,95% dos animais foram positivos, respectivamente. Segundo a aptidão zootécnica, 91,22% dos bovinos com aptidão para corte e 90,91% dos bovinos com aptidão para leite foram positivos. Em relação ao sexo, 91,35% das fêmeas e 88,57% dos machos foram positivos. Não houve diferença significativa (P>0,05) entre os grupos etários, entre os sexos e entre as aptidões zootécnicas. A prevalência entre os municípios não diferiu significativamente (P>0,000), demonstrando que a infecção por A. marginale em bovinos é alta e homogênea entre os municípios. A mesorregião estudada foi caracterizada como uma área de estabilidade enzoótica.

Evaluation of an enzyme-linked immunosorbent assay to detect antibodies against Anaplasma marginale

A rapid indirect enzyme-linked immunosorbent assay (ELISA) was developed for measuring antibodies against Anaplasma marginale using a partially soluble antigen prepared from semi-purified initial bodies from erythrocytes with 80.0% of rickettsiaemia. This technique utilized alkaline phosphatase and p-nitrophenyl phosphate as reaction indicators. The high sensitivity (100.0%) was confirmed with sera from 100 calves experimentally-infected with A. marginale. All of these animals showed seroconversion before or at the same time of the first rickettsiaemia or even when it was not detected. Also the elevated specificity (94.0%) was confirmed by the low percentage of cross-reactions with sera from animals experimentally-infected with Babesia bigemina and Babesia bovis (1.4 and 6.6%, respectively). Performances of ELISA and indirect fluorescent antibody test (IFAT) with 324 sera from enzootically stable area did not show statistical difference (P>0.05), since the former showed 96.9% and the latter 97.2% of positive reactions. The advantage of this ELISA is a shorter execution time than others developed until now, allowing more samples to be analyzed.

Low cost production and purification of polyclonal antibodies to staphylococcal enterotoxin A

An immunization scheme for production of antiserum to staphylococcal enterotoxin A (SEA) is proposed. The reference method of Robbins and Bergdoll was modified to reduce the number of doses and the amount of toxin used per animal. The best immunization scheme used injections in days 0,8,24,59,62 and 67. The amount of toxin at each injection was 5,6,20,50,100 and 200ug, respectively. The total amount of toxin was 381ug, which corresponded to a reduction of 107ug in the amount of toxin for each animal when compared to the reference method. The average antiserum titer using the Optimum Sensitivity Plate - OSP was 1:60 and using ELISA the titer was 1:100.000. The lack of cross-reactivity with other staphylococcal enterotoxins indicated high specificity of the antibody to SEA. The proposed immunization scheme was adequate to produce specific SEA antisera, with high titers and the aditional advantage of reducing the amount of purified SEA required for immunization.

Post cardiac injury syndrome--one more cause of false positive IgG, IgM antibodies in pleural fluid against antigen-60 of Mycobacterium tuberculosis.

Post cardiac injury syndrome (PCIS) is known to occur following myocardial infarction, cardiac surgery, blunt chest trauma, percutaneous left ventricular puncture and pace-maker implantation. The diagnosis is one of exclusion. We report a case of PCIS following cardiac surgery who showed false positive IgG, IgM antibodies to antigen A60 of Mycobacterium tuberculosis in pleural fluid.

Evaluacion de sensibilidad, especificidad y valor predictivo de seis metodos serologicos cualitativos para la deteccion de anticuerpos contra el Helicobacter pylori / Evaluation of sensitivity, specificity and predictive value of six qualitative serological methods for the detection of Helicobacter pylori antibodies

El diagnóstico de infección por H.P. incluye: test rápido de la ureasa y cultivo de biopsia gástrica, urea breath test y detección de Atc Ig G. Existe una fuerte correlación entre la positividad de estos tests y la demonstración histológica de dicho microorganismo. El objetivo de nuestro trabajo fue: determinar y comparar la sensibilidad, especificidad y valor predictivo positivo y negativo de seis equipos comerciales para la detección serológica cualitativa de atc IgG, para el diagnóstico de H.P. Se estudiaron 52 pacientes (58 por ciento masculino, 42 por ciento femenino) con edad promedio 42,4 años con diagnóstico úlcera péptica gastro-duodenal o gastritis erosiva, H. Pylori positivo por test de la ureasa e histología convencional (Giemsa) en 2 biopsias de antro y 2 de cuerpo. El grupo control incluía 10 individuos con histología y test de la ureasa negativos. Los seis tests serológicos evaluados tenían sensibilidad y especificidad comparable, (89-95 por ciento) y (77-83 por ciento) respectivamente. La presencia de anticuerpos específicos contra H.P. en pacientes infectados reveló una fuerte correlación con la demonstración histológica del microorganismo. Recomendamos estos tests serológicos cualitativos debido a su alta sensibilidad y especificidad, bajo costo, sencillez y rapidez para su realización.

Microbiological studies on cases diagnosed as typhoid/enteric fever in south-east Nigeria.

Eight hundred and nine patients suspected of having typhoid/enteric fever were investigated. Enteric fever bacilli (Salmonella typhi and S. paratyphi) were cultured from stool samples of 128 (16%) patients. Serological evidence of typhoid fever was obtained in 83 (13%) of 620 of the patients examined by the Widal test. The antibody titres ranged from 1:160 to 1:1280. A higher proportion of paratyphoid infection over typhoid infection was recorded both by culture (56%) and by the Widal test (63%). The predominant serotype was paratyphi C. Non-typhoid Salmonellae were recovered from stool samples of 60 patients, comprising five serovars, namely, S. typhimurium-22 strains, S. enteritidis-15, S. hardar-9, S. virchow-5, S. bredeney-3, and 6 non-typable strains. Shigella sonnei and S. flexneri were detected in diarrhoeic and semi-formed stools of 19 (2.3%) of the typhoid suspects. It is clear from the results of the study that though typhoid is endemic in South-East Nigeria and the number of cases may rise at certain periods of the year, the news of a current wave of epidemic of typhoid seem unfounded.

Antigen profile of Helicobacter pylori strains isolated from peptic ulcer patients in Dhaka, Bangladesh.

The whole-cell-extract and the acid-extract preparations of Helicobacter pylori strains isolated from peptic ulcer patients and the NCTC 11638 control strain were studied to compare their antigen profiles. Besides, the anti-H. pylori-antibody profile in serum from H. pylori-infected peptic ulcer patients were also studied to define the antigen stimulating specific anti-H. pylori-antibody response in the infected patients. The whole-cell extract (WCE) and the acid-extract (AE) preparations showed a general antigenic homogeneity among the H. pylori strains isolated from the patients and the NCTC 11638 control strain. A humoral immune response against the infecting organism was observed and three antigenic bands of approximate molecular masses of 61 kDa, 58 kDa and 24 kDa were recognized by all the tested sera. Those bands were found to be unique for H. pylori and did not show any cross reaction with the Campylobacter jejuni antigenic bands. This makes them a candidate for the specific antigens required to develop a specific serological diagnostic test. Further purification and characterization of the protein bands may be carried out to define their probable diagnostic or immuno-pathogenic role.

Serosurvey of some major zoonotic infections in children and teenagers in Bali, Indonesia.

One hundred and ninety serum samples, mainly from children and teenagers, from northeast Bali were tested for the presence of antibodies against five zoonotic agents: Brucella abortus, Coxiella burnetii, Toxoplasma gondii, Toxocara canis and Trichinella spiralis. All children were negative for brucellosis and Q fever. A high prevalence rate was found for toxocariasis (63.2%) and trichinosis (19.5%). Antibody prevalence against T. gondii was found to be rather low (3.1%). To our knowledge, this is the first evidence of toxoplasmosis, toxocariasis and trichinosis infection in humans on Bali. Eating habits and poor hygiene may explain the frequency of parasitic infestations in the children and teenagers in Bali.