Keywords
HTLV-2
Western blot (WB)
Real-time polymerase chain reaction (PCR)
Algorithm tests
How to Cite
Abstract
Since 1998 the Instituto Adolfo Lutz of São Paulo (IAL) has conducted serologic assays for human T-cell lymphotropic virus type 1 and type 2 (HTLV-1 and HTLV-2) in blood samples from patients from public health centers. Based on the skillful experience and the faced difficulties, the investigators of IAL evaluated several testing algorithm, searching for the most appropriate one. The present study assessed the cost-effectiveness of two test algorithms for confirming HTLV infections: Algorithm A, proposed in 2009, employs firstly the Western Blot (WB) assay and those samples with negative or inconclusive results are analyzed by real-time polymerase chain reaction (PCR) pol; and Algorithm B, proposed in 2010, employs firstly the real-time PCR, and negative samples are tested by WB. Of 73 analyzed blood samples, 53 were HTLV-1/2 positive in the algorithms. However, Algorithm A showed 19 inconclusive results, and 37% of which were confirmed by realtime PCR. Using Algorithm B, 11 blood samples showed false-negative results in real-time PCR. Thus, both confirmatory assays were complementary. Due to the high number of indeterminate results and the cost for running WB, the Algorithm B seemed to be mostly suitable. A 44% cost reduction was observed in using Algorithm B. In conclusion, in laboratories equipped to handle the real-time PCR, this assay could be employed for reducing the cost for the public health system.
References
Proietti FA, Carneiro-Proietti ABF, Catalan-Soares BC, Murphy EL. Global epidemiology of HTLV-I infection and associated diseases. Oncogene. 2005; 24(39):6058-68.
Posada-Vergara MP, Montanheiro P, Fukumori LMI, Bonasser F, Duarte AJS, Penalva De Oliveira AC et al. Clinical and epidemiological aspects of HTLV-II infection in São Paulo, Brazil: presence of tropical spastic paraparesis/HTLVassociated myelopathy (TSP/HAM) simile diagnosis in HIV-1-co-infected subjects. Rev Inst Med Trop S Paulo. 2006; 48(4):207-10.
Orland JR, Engstrom J, Fridey J, Sacher RA, Smith JW, Nass C et al. Prevalence and clinical features of HTLV neurologic disease in the HTLV outcomes study. Neurol. 2003; 61(11): 1588-94.
CDC - Centers for Disease Control and Prevention. Current trends licensure of screening tests for antibody to human T-lymphotropic virus type I. MMWE Morb Mortal Wkly Rep. 1988; 37(48): 736-40. [acesso em 11 set. 2001]. Disponível em: http://www.cdc.gov/ mmwr/preview/mmwrhtml/00001311.htm.
Hartley MT, Malone GE, Khabbaz RF, Lal RB, Kaplan JE. Evaluation of a recombinant human T-cell lymphotropic virus type I (HTLV-I) p21E antibody detection enzyme immunoassay as a supplementary test in HTLV-I/II antibody testing algorithms. J Clin Microbiol. 1991; 29(6): 1125-7.
Caterino-de-Araujo A. Best screening assays for the diagnosis of human T-cell lymphotropic virus types 1 and 2 in South America. J Virol Methods. 2009; 156(1-2): 150-1.
Berini, C.A., Pascuccio, S., Bautista, C.T., Gendler, S.A., Eirin, M.E., Rodrigues, C., Pando, M.A., Biglione, M.M., 2008. Comparison of four commercial screening assays for the diagnosis of human T-cell lymphotropic virus types 1 and 2. J. Virol. Methods 147, 322–7.
Jacob F, Santos-Fortuna E, Azevedo RS, Caterino-de-Araujo A. Performances of HTLV serological tests in diagnosing HTLV infection in high-risk population of Sao Paulo, Brazil. Rev Inst Med Trop Sao Paulo. 2007; 49(6): 361-4.
Wiktor SZ, Alexander SS, Shaw GM, Weiss SH, Murphy EL, Wilks RJ et al. Distinguishing between HTLV - 1/I and HTLV - 2/II by Western blot. Lancet. 1990; 335(8704): 1533.
Poiesz BJ, Dube S, Choi D, Esteban E, Ferrer J, Leon-Ponte M et al. Comparative performances of an HTLV-I/II EIA and other serologic and PCR assays on samples from persons at risk for HTLV-II infection. Transfusion. 2000; 40(8): 924-30.
Césaire R, Bera O, Maier H, Lezin A, Martial J, Ouka M et al. Seroindeterminate patterns and seroconversions to human T-lymphotropic virus type I positivity in blood donors from Martinique, french west Indies Transfusion. 1999; 39(10): 1145-9.
Mangano AM, Remesar M, del Pozo A, Sen L. Human T lymphotropic virus types I and II proviral sequences in Argentinian blood donors with indeterminate Western blot patterns. J Med Virol. 2004; 74(2): 323-7.
Jacob F, Santos-Fortuna E, Azevedo RS, Caterino-de-Araujo A. Serological patterns and temporal trends of HTLV-1/2 infection in high-risk populations attending Public Health Units in São Paulo, Brazil. J Clin Virol. 2008; 42(2): 149-55.
Tamegão-Lopes BP, Rezende PR, Maradei-Pereira LMC, Lemos JAR. HTLV-1 and HTLV-2 proviral load: a simple method using quantitative real-time PCR. Rev Soc Bras Med Trop S Paulo. 2006; 39(6): 548-52.
Costa JMP, Segurado AC. Molecular evidence of human T-cell lymphotropic virus types 1 and 2 (HTLV-1 and HTLV-2) infections in HTLV seroindeterminate individuals from São Paulo, Brazil. J Clin Virol. 2009; 44(3): 185-9.
Andrade RG, Ribeiro MA, Namen-Lopes MSS, Silva SMN, Basques FV, Ribas JG et al. Análise do uso da PCR em tempo real para HTLV-1 e 2 como teste confirmatório na triagem de doadores de sangue. Rev Soc Bras Med Trop S Paulo. 2010; 43(2): 111-5.
Caterino-de-Araujo A, Santos-Fortuna E, Meleiro MCZ, Suleiman J, Calabro ML, Favero A et al. Sensitivity of two enzymelinked immunosorbent assay tests in relation to Western blot in detecting human T-cell lymphotropic virus types I and II infection among HIV-1 infected patients form São Paulo, Brazil. Diagn Microbiol Infect Dis. 1998; 30(3):173-82.
Jacob F, Santos-Fortuna E, Caterino-de- Araujo A. Algoritmo de testes sorológicos de triagem para infecção por HTLV-1/2 usado no Instituto Adolfo Lutz de São Paulo. BEPA - Bol Epidemiol Pauli. 2008; 5(23): 12-8.
Jacob F, Magri MC, Costa EAS, Santos- Fortuna E, Caterino-de Araujo A. Comparison of signal-to-cutoff values in first, second, and third generation enzyme immunoassays for the diagnosis of HTLV-1/2 infection in “at-risk” individuals from São Paulo, Brazil. J Virol Methods. 2009; 159: 288-90.
Caterino-de-Araujo A. Diagnóstico de infecção por vírus linfotrópicos de células T humanas dos tipos 1 (HTLV-1) e -2 (HTLV-2) em população de risco: passado, presente e futuro. Rev Inst Adolfo Lutz. 2009; 68(2): 182-6.
Morimoto HK, Morimoto AA, Reiche EMV, Ueda LT, Matsuo T, Reice FV et al. Difficulties in the diagnosis of HTLV-2 infection in HIV/AIDS patients from Brazil: Comparative performances of serologic and molecular assays, and detection of HTLV-2b subtype. Rev Inst Med Trop S Paulo. 2007; 49(4): 225-30.
Costa EAS, Jacob F, Feliciano R, Santos- Fortuna E, Caterino-de-Araujo A. Falha na implantação de um novo algoritmo de testes laboratoriais para o diagnóstico de infecção por HTLV-1 e HTLV-2 em população de risco. Rev Inst Adolfo Lutz. 2009; 68(2): 314-7.
Costa EAS. Introdução da reação em cadeia da polimerase em tempo real no algoritmo de testes laboratoriais para o diagnóstico de infecção por HTLV-1 e HTLV-2. [Dissertação de Mestrado] São Paulo Programa de Pós Graduação em Ciências da Coordenadoria de Controle de Doenças da Secretaria de Estado da Saúde, 2010. 101pp.
Costa EAS, Magri MC, Caterino-de Araujo A. The best algorithm to confirm the diagnosis of HTLV-1 and HTLV-2 in atrisk individuals from São Paulo, Brazil. J Virol Methods. 2011;173(2):280-6.
Sabino EC, Carvalho SMF. Diagnóstico laboratorial do HTLV. In: PROIETTI ABFC (org) ed. HTLV - Cadernos Hemominas. 2006; 8: 61-8.
Thorstensson R, Albert J, Andersson S. Strategies for diagnosis of HTLV-I and –II. Transfusion. 2002; 42(6): 780-91.
Medrano FJ, Soriano V, Calderón EJ, Rey C, Gutiérrez M, Bravo R et al. Significance of indeterminate reactivity to human T-cell lymphotropic virus in Western blot analysis of individuals at risk. Eur J Clin Microbiol Infect Dis. 1997; 16(3): 249-52.
Olah I, Fukumori LMI, Smid J, Penalva de Oliveira AC, Duarte AJS, Casseb J. Neither molecular diversity of envelope, immunosuppression status, nor proviral load causes indeterminate HTLV Western blot profiles in samples from human Tcell lymphotropic virus type 2 (HTLV-2)- infected individuals. J Med Virol. 2010; 82: 837-42.
Montanheiro PA, Olah I, Fukumori LMI, Smid J, Penalva de Oliveira AC, Kanzaki LIB et al. Low DNA HTLV-2 proviral load among women in São Paulo City. Virus Res. 2008; 135: 22-5.
Machuca A, Soriano V. In vivo fluctuation of HTLV-I and HTLV-II proviral load in patients receiving antiretroviral drugs. J Acquir Immune Defic Syndr. 2000; 24(2):189-93.
This work is licensed under a Creative Commons Attribution 4.0 International License.
Copyright (c) 2011 Emanuela Avelar Silva Costa, Adele Caterino-de-Araujo, Karoline Rodrigues Campos