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Western blot profile in HIV infection
Sudha T,Lakshmi V,Teja V
Indian Journal of Dermatology, Venereology and Leprology , 2006,
Abstract: Background: Although the overall sensitivity and specificity of the western blot (WB) test for detection of antibodies to various viral proteins is high, there has been a substantial difference in the timing of the appearance of antibody bands and their intensities during different stages of HIV infection. Aims: Mapping different band patterns of Western blot results and correlating them with stages of HIV infection. Methods: We performed a retrospective study with 1,467 HIV-1 infected cases confirmed by WB test between January 2002 to July 2005, with the objective of mapping different band patterns of western blot results and determining whether the presence or absence of certain bands was associated with any specific stage of HIV infection. For the interpretation of the WB results in this study, the guidelines recommended by NACO, India were followed. Results: Reactivity with all the bands was the most commonly observed WB pattern, occurring in 92.91% (1363/1467) of cases, whereas the other 7.09% showed uncommon band patterns. Of all individual bands, p31 band was the most frequently missing one, absent in 7.09% cases. On classifying the WB reactive cases by the WHO clinical staging system, 38.45% (564/1467) were in Stage 1, 47.99% (704/1467) in stages 2 and 3 and 13.56% in stage 4. Correlation of CD4 cell counts with the various uncommon band patterns showed that only 5.56% (4/72) had counts in the 200-500 cells/μl range, whereas 45.83% and 48.61% had counts of < 200 and> 500 cells/μl respectively. Conclusion: Interpretation of the WB band pattern in combination with clinical features may be occasionally useful in predicting the stage of HIV infection.
Profile of Anti-Tp47 antibodies in patients with positive serology for syphilis analized by western blot
Miranda, Ana Paula Félix de;Sato, Neuza Satomi;
Brazilian Journal of Infectious Diseases , 2008, DOI: 10.1590/S1413-86702008000200008
Abstract: in brazil, syphilis is still a great problem of public health. serological test is essential for syphilis diagnosis and the current trend is the use of recombinant antigen in the treponemal tests, due to its confirmed higher sensibility and specificity. the purpose of the present study was to analyze the profile of anti-tp47 antibodies in patients with positive serology for syphilis. one hundred positive sera samples were analyzed by western blot (wb) technique, using the recombinant antigen (rtp47). ten of them did not present antibodies against the fraction rtp47, the results were confirmed by wb using native t. pallidum antigen. all ten samples had antibodies against the fractions tp17 and tp15 and presented low reactivity in vdrl, negative results or title below than 1:4. considering that vdrl is used for therapeutic monitoring due to seroreversion of nontreponemal antibodies in response to the treatment, and that some studies reported loss of treponemal antibodies after treatment, we could speculate if these ten samples are cases of serological memory from patients previously treated for syphilis. in addition, although several features state the tp47 fraction as one of the major antigenic components, based on our results we point out to the importance of including other antigenic proteins such as tp17 and tp15 in addition to tp47 in tests for serological screening of syphilis.
Positive IgG Western Blot for Borrelia burgdorferi in Colombia
Palacios, Ricardo;Osorio, Lyda E;Giraldo, Luis E;Torres, Antonio J;Philipp, Mario T;Ochoa, Maria Teresa;
Memórias do Instituto Oswaldo Cruz , 1999, DOI: 10.1590/S0074-02761999000400013
Abstract: in order to evaluate the presence of specific igg antibodies to borrelia burgdorferi in patients with clinical manifestations associated with lyme borreliosis in cali, colombia, 20 serum samples from patients with dermatologic signs, one cerebrospinal fluid (csf) sample from a patient with chronic neurologic and arthritic manifestations, and twelve serum samples from individuals without clinical signs associated with lyme borreliosis were analyzed by igg western blot. the results were interpreted following the recommendations of the centers for diseases control and prevention (cdc) for igg western blots. four samples fulfilled the cdc criteria: two serum specimens from patients with morphea (localized scleroderma), the csf from the patient with neurologic and arthritic manifestations, and one of the controls. interpretation of positive serology for lyme disease in non-endemic countries must be cautious. however these results suggest that the putative "lyme-like" disease may correlate with positivity on western blots, thus raising the possibility that a spirochete genospecies distinct from b. burgdorferi sensu stricto, or a borrelia species other than b. burgdorferi sensu lato is the causative agent. future work will focus on a survey of the local tick and rodent population for evidence of spirochete species that could be incriminated as the etiologic agent.
Positive IgG Western Blot for Borrelia burgdorferi in Colombia  [cached]
Palacios Ricardo,Osorio Lyda E,Giraldo Luis E,Torres Antonio J
Memórias do Instituto Oswaldo Cruz , 1999,
Abstract: In order to evaluate the presence of specific IgG antibodies to Borrelia burgdorferi in patients with clinical manifestations associated with Lyme borreliosis in Cali, Colombia, 20 serum samples from patients with dermatologic signs, one cerebrospinal fluid (CSF) sample from a patient with chronic neurologic and arthritic manifestations, and twelve serum samples from individuals without clinical signs associated with Lyme borreliosis were analyzed by IgG Western blot. The results were interpreted following the recommendations of the Centers for Diseases Control and Prevention (CDC) for IgG Western blots. Four samples fulfilled the CDC criteria: two serum specimens from patients with morphea (localized scleroderma), the CSF from the patient with neurologic and arthritic manifestations, and one of the controls. Interpretation of positive serology for Lyme disease in non-endemic countries must be cautious. However these results suggest that the putative "Lyme-like" disease may correlate with positivity on Western blots, thus raising the possibility that a spirochete genospecies distinct from B. burgdorferi sensu stricto, or a Borrelia species other than B. burgdorferi sensu lato is the causative agent. Future work will focus on a survey of the local tick and rodent population for evidence of spirochete species that could be incriminated as the etiologic agent.
Use of a Western blot technique for the serodiagnosis of glanders
Mandy C Elschner, Holger C Scholz, Falk Melzer, Muhammad Saqib, Peggy Marten, Astrid Rassbach, Michael Dietzsch, Gernot Schmoock, Vania L de Assis Santana, Marcilia MA de Souza, Renate Wernery, Ulrich Wernery, Heinrich Neubauer
BMC Veterinary Research , 2011, DOI: 10.1186/1746-6148-7-4
Abstract: The developed Western blot assay showed a markedly higher diagnostic specificity when compared to the prescribed CFT and therefore can be used as a confirmatory test. However, the CFT remains the test of choice for routine testing of glanders due to its high sensitivity, its feasibility using standard laboratory equipment and its worldwide distribution in diagnostic laboratories.The CFT should be amended by the newly validated Western blot to increase the positive likelihood ratio of glanders serodiagnosis in non endemic areas or areas with low glanders prevalence. Its use for international trade of horses and mules should be implemented by the OIE.Glanders, caused by Burkholderia (B.) mallei, is a highly contagious disease in equines which is notifiable to the World Organisation of Animal Health (OIE, Office International des Epizooties). The disease is still endemic in the Middle East, Asia and South America. Recent outbreaks have been reported from Turkey, the United Arabic Emirates, Iraq, Iran, India, Pakistan, Mongolia, China, Brazil and most recently from Bahrain [1-11]. The distribution of glanders in Africa is unknown.The diagnosis of B. mallei infection still relies on serological proof by agglutination test and complement fixation test (CFT), or proof of the presence of a specific delayed hypersensitivity reaction after intracutaneous application of mallein [12,13]. The CFT for glanders is so far the only officially recognized serological test in international trade of equidae. The CFT has a sensitivity of at least 97% [14] but a notable number of unspecific, false positive results occur [15-18]. False positive results due to cross-reactions may be seen in horses suffering from strangles, equine influenza or petechial fever. The test can also not be applied on sera having so called "anticomplementary activity". In general, serological tests may be negative in emaciated and chronically debilitated animals suffering from glanders [16].Glanders was eradicated
Evaluation of an indigenous western blot kit for human immunodeficiency virus  [cached]
Lakshmi V,Ponamgi S
Indian Journal of Medical Microbiology , 2002,
Abstract: PURPOSE: The Western Blot test is considered a gold standard test for the confirmation of an ELISA and/or rapid assay screened reactive sample in the diagnosis of HIV infection, especially in the low risk population. In this study, an indigenously developed HIV W. Blot kit (J.Mitra & Co., New Delhi, India) was compared for its performance characteristics with a widely used Western Blot kit, HIV Blot 2.2 (Genelabs, Singapore). Antigens of both HIV-1 and the indicator antigen gp36 of HIV-2 are included in the strips. METHODS: A panel of 150 clinical serum samples was used in the evaluation. All the sera were tested simultaneously by both the kits. RESULTS: The HIV W. Blot kit had high performance characteristics (100% sensitivity and 100% specificity), like the HIV Blot 2.2. The test procedure was easy to perform. There was clear delineation of the bands. CONCLUSIONS: The interpretation of the results on the HIV W. Blot was less prone to subjective errors. The test gave positive bands at even very high serum dilutions in the test kit. This fact indicates that HIV W. Blot probably has a potential application in early phases of infection, when the antibody concentrations are still very low.
HIV-1 western blot assay: What determines an indeterminate status?  [cached]
Syed Iqbal,Balakrishnan P,Solomon Sunil,Murugavel K
Indian Journal of Medical Sciences , 2005,
Abstract: Background: The Western blot assay is the gold standard for the detection of antibodies to human immunodeficiency virus type1 (HIV-1). However, indeterminate Western blot reactivity to HIV-1 proteins may occur in individuals, who may not be infected with HIV. Aim: This retrospective study was aimed to determine the diagnostic value of the interpretation criteria in relation to commercial kits for HIV -1 diagnosis. Methods and Materials: A total of 556 serum/plasma specimens collected from high-risk population attending our HIV clinic from 2000 - 2004 were tested by three different western blot kits: NEW LAV BLOT I (n=244), HIV BLOT 2.2; (n=112), Genetic Systems HIV-1 (n=237). And the results of western blot strips were analyzed using the various interpretation criteria: WHO/NACO, CDC/ ASTPHLD, ARC, FDA, CRSS and JHU. Some specimens were run on more than one kit. RT-PCR assay was performed on 5 specimens, which were indeterminate with LAV BLOT I. Results: The discrepancy in LAV BLOT I positive results were between 157(64)-176(72), and indeterminate results were between 44(18) to 63(25). No such variations were observed in genetic systems. There are some HIV negative (by PCR) specimens were indeterminate in LAV BLOT I revealing the kit more sensitive and less effective for diagnostic purpose. Conclusion: The genetic systems kit is superior to other kits we analyzed and its results are concordant with HIV-1 PCR results. To report, the choice of western blot commercial kit is paramount important than the use of particular interpretation criteria for the diagnosis of HIV -1.
Combined use of Western blot/ELISA to improve the serological diagnosis of human tuberculosis
Beck, S. T.;Leite, O. M.;Arruda, R. S.;Ferreira, A. W.;
Brazilian Journal of Infectious Diseases , 2005, DOI: 10.1590/S1413-86702005000100007
Abstract: two recombinant antigens and a crude bacterial antigen of a wild m. tuberculosis strain were used to detect specific igg antibodies in sera from 52 patients with pulmonary tuberculosis, confirmed by an acid-fast smear and serum culture of these patients and that of 25 contacts. the patients were not infected with hiv. we evaluated the sensitivity and specificity of elisa, based on the recombinant tbf6? and tbf6/dpep antigen and a search for reactivity patterns in the western blot technique, using whole mycobacterium antigen. serum samples from 22 healthy individuals and from 30 patients with lung diseases other than tuberculosis were used as controls. the best elisa results were obtained with the tbf6/dpep antigen combination, which gave 85% sensitivity and 91% specificity. elisa sensitivity improved from 85% to 92% when the western blot results were used. western blot specificity was 100% when antibody reactivity with different antigenic bands was analyzed and associated. the association of tbf6/dpep antigens used in elisa with specific patterns of reactivity determined by western blot can help make an identification when classic methods for the diagnosis of pulmonary tuberculosis are not sufficient.
Serological follow-up of patients with paracoccidioidomycosis treated with itraconazole using Dot-blot, ELISA and Western-blot
MARTINS, Rosana;MARQUES, Sílvio;ALVES, Marino;FECCHIO, Denise;FRANCO, Marcello F. de;
Revista do Instituto de Medicina Tropical de S?o Paulo , 1997, DOI: 10.1590/S0036-46651997000500004
Abstract: twenty-seven mycologically proven cases of paracoccidioidomycosis (pcm) were treated with itraconazole (100-200 mg/day in month 1 and 100 mg/day until month 6-8) and evaluated clinically and serologically, up to 3.5 years post-therapy, using dot-blot and elisa for measuring the titers of igg, iga and igm anti-p. brasiliensis antibodies and western-blot for determining igg, iga and igm antibodies against the antigen components of the fungus. before treatment, 81.5% (dot-blot) and 84% (elisa) of the patients presented elevated igg anti-p. brasiliensis antibody titers which dropped slightly with treatment. on the other hand, the percentages of pre-treatment high-titered sera for iga and igm anti-p.brasiliensis were lower (5l.9% and 5l.8%: dot-blot; 16.5 and 36%: elisa, respectively) but the titers tended to become negative more frequently with treatment. prior to treatment, the percentages of positivity for igg, iga and igm anti-p.brasiliensis antibodies in western-blot were 96%, 20.8% and 41.6%, respectively. antigens with molecular weights varying from 16-78 kda, from 21-76 kda and from 27-78 kda were reactive for igg, iga and igm antibodies, respectively. the most frequently reactive antigenic components had molecular weights of 27, 33 and 43 kda for igg, and 70 for iga and igm antibodies. during the period of study, the patients responded well to treatment. the present data confirm the diversity and complexity of the humoral response in pcm, and the importance of utilizing different serological tests to detect igg, iga and igm anti-p. brasiliensis antibodies
Serological follow-up of patients with paracoccidioidomycosis treated with itraconazole using Dot-blot, ELISA and Western-blot  [cached]
MARTINS Rosana,MARQUES Sílvio,ALVES Marino,FECCHIO Denise
Revista do Instituto de Medicina Tropical de S?o Paulo , 1997,
Abstract: Twenty-seven mycologically proven cases of paracoccidioidomycosis (PCM) were treated with itraconazole (100-200 mg/day in month 1 and 100 mg/day until month 6-8) and evaluated clinically and serologically, up to 3.5 years post-therapy, using Dot-blot and ELISA for measuring the titers of IgG, IgA and IgM anti-P. brasiliensis antibodies and Western-blot for determining IgG, IgA and IgM antibodies against the antigen components of the fungus. Before treatment, 81.5% (Dot-blot) and 84% (ELISA) of the patients presented elevated IgG anti-P. brasiliensis antibody titers which dropped slightly with treatment. On the other hand, the percentages of pre-treatment high-titered sera for IgA and IgM anti-P.brasiliensis were lower (5l.9% and 5l.8%: Dot-blot; 16.5 and 36%: ELISA, respectively) but the titers tended to become negative more frequently with treatment. Prior to treatment, the percentages of positivity for IgG, IgA and IgM anti-P.brasiliensis antibodies in Western-blot were 96%, 20.8% and 41.6%, respectively. Antigens with molecular weights varying from 16-78 kDa, from 21-76 kDa and from 27-78 kDa were reactive for IgG, IgA and IgM antibodies, respectively. The most frequently reactive antigenic components had molecular weights of 27, 33 and 43 kDa for IgG, and 70 for IgA and IgM antibodies. During the period of study, the patients responded well to treatment. The present data confirm the diversity and complexity of the humoral response in PCM, and the importance of utilizing different serological tests to detect IgG, IgA and IgM anti-P. brasiliensis antibodies
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