RESUMEN
We assessed the diagnostic ability of an enzyme-linked immunosorbent assay test for measurement of specific secretory IgA (sIgA) in saliva to identify cystic fibrosis (CF) patients with Pseudomonas aeruginosa chronic lung infection and intermittent lung colonization. A total of 102 Brazilian CF patients and 53 healthy controls were included. Specific serum IgG response was used as a surrogate to distinguish CF patients according to their P. aeruginosa colonization/infection status. The rate of sIgA positivity was 87.1% in CF chronically infected patients (median value = 181.5 U/mL), 48.7% in intermittently colonized patients (median value = 45.8 U/mL) and 21.8% in free of infection patients (median value = 22.1 U/mL). sIgA levels in saliva were significantly associated with serum P. aeruginosa IgG and microbiological culture results. The sensitivity, specificity, PPV and NPV for differentiation between presence and absence of chronic lung infection were 87%, 63%, 51% and 92%, respectively. Measurement of sIgA in saliva may be used for screening patients in risk of developing P. aeruginosa chronic lung infection in CF and possibly also for paranasal sinusitis, and, most importantly, to efficiently rule out chronic P. aeruginosa lung infection.
Asunto(s)
Anticuerpos Antibacterianos/análisis , Fibrosis Quística/diagnóstico , Inmunoglobulina A Secretora/análisis , Inmunoglobulina G/análisis , Infecciones Oportunistas/diagnóstico , Infecciones por Pseudomonas/diagnóstico , Saliva/química , Adolescente , Adulto , Estudios de Casos y Controles , Niño , Preescolar , Estudios Transversales , Fibrosis Quística/complicaciones , Fibrosis Quística/inmunología , Fibrosis Quística/microbiología , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Pulmón/inmunología , Pulmón/microbiología , Pulmón/patología , Masculino , Infecciones Oportunistas/complicaciones , Infecciones Oportunistas/inmunología , Infecciones Oportunistas/microbiología , Infecciones por Pseudomonas/complicaciones , Infecciones por Pseudomonas/inmunología , Infecciones por Pseudomonas/microbiología , Pseudomonas aeruginosa , Saliva/inmunología , Saliva/microbiología , Sensibilidad y EspecificidadRESUMEN
Cerebral toxoplasmosis can be highly debilitating and occasionally fatal in persons with immune system deficiencies. In this study, we evaluated the Toxoplasma gondii-specific IgG subclass antibody response in 19 cerebrospinal fluid (CSF) samples from patients with cerebral toxoplasmosis who had a positive IgG anti-T. gondii ELISA standardized with a cyst antigen preparation. There were no significant differences between the rates of positivity and the antibody concentrations (arithmetic means of the ELISA absorbances, MEA) for IgG1 and IgG2, but the rates of positivity and MEA values for these two IgG subclasses were significantly higher than those for IgG3 and IgG4. The marked IgG2 response in CSF from patients with cerebral toxoplasmosis merits further investigation.
Asunto(s)
Anticuerpos Antiprotozoarios/líquido cefalorraquídeo , Inmunoglobulina G/líquido cefalorraquídeo , Toxoplasma/inmunología , Toxoplasmosis Cerebral/líquido cefalorraquídeo , Ensayo de Inmunoadsorción Enzimática , HumanosRESUMEN
We report a primary response to Toxoplasma gondii following a hematopoietic stem cell transplantation in a patient with multiple myeloma. The primary response to T. gondii was supported by IgM, IgG and IgA seroconversion. The patient was promptly treated and there were no complications related to toxoplasmosis in the subsequent months.
Esse relato de caso descreve uma resposta primária ao Toxoplasma gondii após transplante de células progenitoras hematopoiéticas em paciente com mieloma múltiplo. A resposta primária para o T. gondii foi evidenciada pela soroconversão observada na resposta de anticorpos IgM, IgG e IgA. O paciente foi prontamente tratado e complicações relacionadas à toxoplasmose não foram observadas nos meses subseqüentes.
Asunto(s)
Humanos , Masculino , Persona de Mediana Edad , Anticuerpos Antiprotozoarios/sangre , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Isotipos de Inmunoglobulinas/sangre , Toxoplasma/inmunología , Toxoplasmosis/inmunología , Ensayo de Inmunoadsorción Enzimática , Mieloma Múltiple/cirugía , Toxoplasmosis/diagnósticoRESUMEN
We report a primary response to Toxoplasma gondii following a hematopoietic stem cell transplantation in a patient with multiple myeloma. The primary response to T. gondii was supported by IgM, IgG and IgA seroconversion. The patient was promptly treated and there were no complications related to toxoplasmosis in the subsequent months.
Asunto(s)
Anticuerpos Antiprotozoarios/sangre , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Isotipos de Inmunoglobulinas/sangre , Toxoplasma/inmunología , Toxoplasmosis/inmunología , Ensayo de Inmunoadsorción Enzimática , Humanos , Masculino , Persona de Mediana Edad , Mieloma Múltiple/cirugía , Toxoplasmosis/diagnósticoRESUMEN
The demonstration of intrathecal antibody production has proven useful for showing the involvement of the central nervous system (CNS) in several diseases. In the present study, the intrathecal synthesis of cysticercus-specific immunoglobulin G (IgG) antibodies was investigated in 30 patients with neurocysticercosis based on calculation of the specific IgG antibody index (AI(IgG)). An AI(IgG) > or =1.5 was considered to be indicative of intrathecal antibody production. Antibody concentrations in serum and cerebrospinal fluid samples were evaluated using an enzyme-linked immunosorbent assay with 2 antigen preparations from Taenia solium cysticerci, namely, a whole cysticercal extract (TsoW) and the vesicular fluid of the parasite (TsoVF). Intrathecal, cysticercus-specific IgG antibody synthesis was observed in 21 (70%) and 23 (76.6%) patients using the TsoW and TsoVF antigens, respectively. The detection of the intrathecal synthesis of specific antibodies may be a potentially useful tool in establishing the involvement of CNS in cysticercosis.
Asunto(s)
Anticuerpos Antihelmínticos/líquido cefalorraquídeo , Antígenos Helmínticos/líquido cefalorraquídeo , Inmunoglobulina G/análisis , Neurocisticercosis/diagnóstico , Taenia/inmunología , Animales , Anticuerpos Antihelmínticos/análisis , Anticuerpos Antihelmínticos/inmunología , Antígenos Helmínticos/inmunología , Líquido Quístico , Cysticercus/inmunología , Ensayo de Inmunoadsorción Enzimática/métodos , Estudios de Evaluación como Asunto , Humanos , Inmunoglobulina G/sangre , Inmunoglobulina G/líquido cefalorraquídeo , Inmunoglobulina G/inmunología , Neurocisticercosis/inmunologíaRESUMEN
OBJECTIVES: The aim of this study was to describe our experience in the control of active CMV infection following HSCT using two strategies of CMV infection treatment: ganciclovir universal prophylaxis at low doses and pre-emptive therapy with ganciclovir. METHODS: The surveillance was based on the monitoring of antigenaemia (AGM) and on a nested polymerase chain reaction (N-PCR) for the detection of CMV in both strategies. Forty-five recipients with malignant diseases and with a risk for CMV disease received universal prophylaxis (Group A). The non-treated group consisted of 24 patients, most of them with non-malignant diseases who did not receive universal prophylaxis (Group B). RESULTS: In Group A, the incidence of positive AGM was 51%, with a positive PCR of 68.9%. In Group B, the AGM positivity was 66.7% and that of N-PCR was 66.7%. CMV disease occurred in 6/55 patients (10.9%), with 2/36 (5.5%) from Group A and 4/19 (21%) from Group B. Two of these six patients (33.3%) died of CMV disease. CONCLUSIONS: Our result suggests that AGM and N-PCR can be used as markers for assessing the monitoring and the introduction pre-emptive therapy. This approach could prove to be more cost-effective than ganciclovir universal prophylaxis for treating CMV infection.
Asunto(s)
Antivirales/uso terapéutico , Infecciones por Citomegalovirus/prevención & control , Citomegalovirus/aislamiento & purificación , Ganciclovir/uso terapéutico , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Vigilancia de la Población , Adolescente , Adulto , Niño , Preescolar , Citomegalovirus/genética , Infecciones por Citomegalovirus/epidemiología , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Fosfoproteínas/sangre , Reacción en Cadena de la Polimerasa , Proteínas de la Matriz Viral/sangreRESUMEN
This article describes the standardization and evaluation of an in-house specific IgG avidity ELISA for distinguishing recent primary from long-term human cytomegalovirus (HCMV) infection. The test was standardized with the commercial kit ETI-CYTOK G Plus (Sorin Biomedica, Italy) using 8 M urea in phosphate-buffered saline to dissociate low-avidity antibodies after the antigen-antibody interaction. The performance of the in-house assay was compared to that of the commercial automated VIDAS CMV IgG avidity test (bioMérieux, France). Forty-nine sera, 24 from patients with a recent primary HCMV infection and 25 from patients with a long-term HCMV infection and a sustained persistence of specific IgM antibodies, were tested. Similar results were obtained with the two avidity methods. All 24 sera from patients with recently acquired infection had avidity indices compatible with acute HCMV infection by the VIDAS method, whereas with the in-house method, one serum sample had an equivocal result. In the 25 sera from patients with long-term infection, identical results were obtained with the two methods, with only one serum sample having an incompatible value. These findings suggest that our in-house avidity test could be a potentially useful tool for the immunodiagnosis of HCMV infection.
Asunto(s)
Humanos , Femenino , Anticuerpos Antivirales , Afinidad de Anticuerpos , Citomegalovirus , Infecciones por Citomegalovirus , Anticuerpos Antivirales , Ensayo de Inmunoadsorción Enzimática , Estudio de Evaluación , Juego de Reactivos para DiagnósticoRESUMEN
Immunodiffusion (ID) is the serologic test most frequently used for the diagnosis and posttherapy follow-up of patients with paracoccidioidomycosis (PCM). The ID test is highly specific (100%), but its sensitivity is relatively low (90%), leading to false-negative results. The aim of this study was to determine the profiles of antibodies in sera from patients with proven PCM and with negative results in the ID test (IDneg) versus positive results in the ID test (IDpos). We analyzed 46 sera from patients with active PCM for total immunoglobulin G (IgG) and IgG subclass responses to Paracoccidioides brasiliensis gp43 antigen (treated or not treated with sodium metaperiodate) by enzyme-linked immunosorbent assay and immunoblotting. Immunoblotting showed that both IDneg and IDpos sera recognized predominantly the gp43 fraction of the P. brasiliensis antigen used in the ID test. IDneg sera contain low-avidity antibodies, low levels of specific IgG (total) and IgG1, and high levels of IgG2 compared with IDpos sera. The antibodies present in IDneg sera were predominantly directed against carbohydrate epitopes, since treatment with sodium metaperiodate resulted in a significant decrease in antibody reactivity. These data suggest that the lack of reactivity of sera from PCM patients in the ID test may be related to the production of low-avidity IgG2 antibodies directed against carbohydrate epitopes.
Asunto(s)
Anticuerpos Antifúngicos/inmunología , Inmunodifusión , Paracoccidioidomicosis/diagnóstico , Paracoccidioidomicosis/inmunología , Animales , Anticuerpos Antifúngicos/sangre , Antígenos Fúngicos/inmunología , Electroforesis en Gel de Poliacrilamida , Ensayo de Inmunoadsorción Enzimática , Proteínas Fúngicas/inmunología , Glicoproteínas/inmunología , Humanos , Immunoblotting , Inmunodifusión/métodos , Inmunoglobulina G/sangre , Inmunoglobulina G/inmunología , Isotipos de Inmunoglobulinas , Paracoccidioides/inmunología , Sensibilidad y EspecificidadRESUMEN
This article describes the standardization and evaluation of an in-house specific IgG avidity ELISA for distinguishing recent primary from long-term human cytomegalovirus (HCMV) infection. The test was standardized with the commercial kit ETI-CYTOK G Plus (Sorin Biomedica, Italy) using 8 M urea in phosphate-buffered saline to dissociate low-avidity antibodies after the antigen-antibody interaction. The performance of the in-house assay was compared to that of the commercial automated VIDAS CMV IgG avidity test (bioM rieux, France). Forty-nine sera, 24 from patients with a recent primary HCMV infection and 25 from patients with a long-term HCMV infection and a sustained persistence of specific IgM antibodies, were tested. Similar results were obtained with the two avidity methods. All 24 sera from patients with recently acquired infection had avidity indices compatible with acute HCMV infection by the VIDAS method, whereas with the in-house method, one serum sample had an equivocal result. In the 25 sera from patients with long-term infection, identical results were obtained with the two methods, with only one serum sample having an incompatible value. These findings suggest that our in-house avidity test could be a potentially useful tool for the immunodiagnosis of HCMV infection.
Asunto(s)
Anticuerpos Antivirales/sangre , Afinidad de Anticuerpos/inmunología , Infecciones por Citomegalovirus/diagnóstico , Citomegalovirus/inmunología , Ensayo de Inmunoadsorción Enzimática/métodos , Inmunoglobulina G/sangre , Anticuerpos Antivirales/inmunología , Femenino , Humanos , Inmunoglobulina G/inmunología , Juego de Reactivos para DiagnósticoRESUMEN
Simple and rapid latex-based diagnostic tests have been used for detecting specific antigens or antibodies in several diseases. In this article, we present the preliminary results obtained with a latex agglutination test (LAT) for diagnosing neurocysticercosis by detection of antibodies in CSF. A total of 43 CSF samples were assayed by the LAT: 19 CSF samples from patients with neurocysticercosis and 24 CSF samples from patients with other neurologic disorders (neurosyphilis, n = 8; neurotoxoplasmosis, n = 3; viral meningitis, n = 4, chronic headache, n = 9). The LAT exhibited 89.5% sensitivity and 75% specificity. The use of LAT seems to be an additional approach for the screening of neurocysticercosis with advantage of simplicity and rapidity. Further studies could be performed using purified antigens and serum samples.
Asunto(s)
Anticuerpos Antihelmínticos/líquido cefalorraquídeo , Cysticercus/inmunología , Pruebas de Fijación de Látex/métodos , Neurocisticercosis/líquido cefalorraquídeo , Animales , Humanos , Neurocisticercosis/inmunología , Sensibilidad y EspecificidadRESUMEN
Simple and rapid latex-based diagnostic tests have been used for detecting specific antigens or antibodies in several diseases. In this article, we present the preliminary results obtained with a latex agglutination test (LAT) for diagnosing neurocysticercosis by detection of antibodies in CSF. A total of 43 CSF samples were assayed by the LAT: 19 CSF samples from patients with neurocysticercosis and 24 CSF samples from patients with other neurologic disorders (neurosyphilis, n = 8; neurotoxoplasmosis, n = 3; viral meningitis, n = 4, chronic headache, n = 9). The LAT exhibited 89.5 percent sensitivity and 75 percent specificity. The use of LAT seems to be an additional approach for the screening of neurocysticercosis with advantage of simplicity and rapidity. Further studies could be performed using purified antigens and serum samples
Asunto(s)
Humanos , Animales , Anticuerpos Antihelmínticos , Cysticercus , Pruebas de Fijación de Látex , Neurocisticercosis , Sensibilidad y EspecificidadRESUMEN
The detection of specific IgM antibodies has been the most frequently used serological marker for diagnosing recent toxoplasmosis. However, the persistence of specific IgM antibodies in some patients and the use of tests with a low specificity have complicated the interpretation of serological results when toxoplasmosis is suspected. The purpose of the present study was to determine the value of newer serological techniques in the diagnosis of acute acquired toxoplasmosis. Sixty-four sera, 31 from patients with Toxoplasma gondii infection and 33 from patients with latent infection, were tested. Anti-T. gondii IgA was measured by two antibody capture ELISA tests (Platelia Toxo IgA and ETI-TOXOK A) and an automated direct ELISA (IMx Toxo IgA); all three assays detected antibody levels compatible with a recent infection in sera from all 31 patients with acute toxoplasmosis. However, significant levels of IgA were also detected with high frequency by all three assays in sera from patients with latent infection. IgE antibodies detected by IgE immunosorbent agglutination assay (ISAGA) were present in 26 (84%) of 31 patients with acute toxoplasmosis and in sera from two subjects with latent infection taken >1 year after the beginning of the clinical symptoms of infection. Thirty (97%) of 31 patients with a recent T. gondii infection and 15 (45%) of 33 subjects with latent infection had an AC/HS pattern compatible with acute toxoplasmosis. The avidity of T. gondii IgG was evaluated by two methods. One method was based on the titration of each serum sample and calculation of the titres, in the absence and presence of urea, in relation to a defined cut-off value. In the other method, a single serum dilution was used and the absorbances of the reactions in the presence and absence of urea were compared. The titration method was more sensitive for diagnosing recent primary infection; all 31 sera from patients with acute toxoplasmosis had avidity indices compatible with acute toxoplasmosis by the titration method, whereas with the single dilution method, sera from four patients had equivocal results. In the 33 individuals with latent infection, similar results were obtained with the two avidity methods; only one serum sample had a non-compatible avidity value with the titration method. The results obtained in the present study show that the current serological markers used for diagnosing acute acquired toxoplasmosis have significant limitations. The data suggest that determination of the avidity of T. gondii-specific IgG by the titration method in patients with detectable IgM antibodies defines most accurately the stage of infection by T. gondii.
Asunto(s)
Anticuerpos Antiprotozoarios/sangre , Toxoplasma/inmunología , Toxoplasmosis/diagnóstico , Enfermedad Aguda , Adolescente , Adulto , Pruebas de Aglutinación , Animales , Anticuerpos Antiprotozoarios/inmunología , Afinidad de Anticuerpos , Biomarcadores/sangre , Niño , Ensayo de Inmunoadsorción Enzimática/métodos , Femenino , Humanos , Inmunoglobulina A/sangre , Inmunoglobulina A/inmunología , Inmunoglobulina E/sangre , Inmunoglobulina E/inmunología , Inmunoglobulina G/sangre , Inmunoglobulina G/inmunología , Técnicas de Inmunoadsorción , Masculino , Persona de Mediana Edad , Juego de Reactivos para Diagnóstico , Toxoplasmosis/parasitologíaRESUMEN
No presente trabalho, sao descritos os resultados da deteccao de anticorpos especificos da classe IgA e da determinacao da avidez dos anticorpos IgG em amostras sequenciais de soro de um paciente apresentando niveis significativos de anticorpos IgM anti-Toxoplasma gondii durante sete anos apos o inicio das manifestacoes clinicas da infeccao. Os anticorpos...
Asunto(s)
Humanos , Masculino , Adulto , Formación de Anticuerpos , Pruebas Serológicas/métodos , Toxoplasmosis/diagnóstico , Afinidad de Anticuerpos/inmunología , Ensayo de Inmunoadsorción Enzimática , Toxoplasmosis/sangre , Toxoplasmosis/inmunologíaRESUMEN
A persistencia, em alguns individuos, de anticorpos especificos IgM anti-Toxoplasma gondii por varios meses, apos a fase aguda da infeccao, tem complicado a interpretacao dos testes sorologicos para a toxoplasmose. Varios trabalhos tem enfatizado o valor da deteccao de anticorpos especificos IgA anti-T. gondii para o diagnostico da toxoplasmose aguda. No presente trabalho, sao apresentados os resultados da pesquisa de anticorpos especificos das classes IgM e IgA anti-T. gondii em amostras de soros de 12 pacientes, obtidas em diferentes intervalos de tempo, apos o inicio das manifestacoes clinicas da infeccao. Os anticorpos IgM foram detectados pelo teste de imunofluorescencia indireta (IFI)...
Asunto(s)
Humanos , Autoanticuerpos/inmunología , Pruebas Inmunológicas , Toxoplasmosis/diagnóstico , Ensayo de Inmunoadsorción Enzimática , Técnica del Anticuerpo Fluorescente Indirecta , Técnicas para Inmunoenzimas , Inmunoglobulina A/inmunología , Inmunoglobulina M/inmunología , Signos y Síntomas , Pruebas Serológicas/métodos , Toxoplasma/inmunología , Toxoplasmosis/transmisiónRESUMEN
Total serum IgE, and Strongyloides-specific IgG and IgA antibodies were studied in 27 patients with parasitologically proven strongyloidiasis. Clinical manifestations in this case series were investigated by a retrospective study of the patient's records. Total serum IgE levels were elevated (greater than 250 IU/ml) in 59 of the patients (mean concentration = 1364 IU/ml). Parasite-specific IgG and IgA antibodies were detected by ELISA in the serum of 23 (85.2) and 21 (77.8) patients, respectively. Elevated serum IgE and clinical manifestations were not useful indexes of the presence of strongyloidiasis. On the other hand, our results support the view that serologic tests, particularly ELISA for detecting Strongyloides-specific IgG antibodies, can be usefully exploited for diagnostic purposes in strongyloidiasis.