Specificity of HTLV screening tests and its impact on health care program costs: The perspective of antenatal screening in Brazil

Abstract INTRODUCTION: Brazil ranks first in the number of HTLV-1/-2-infected individuals worldwide. The high morbidity and mortality of HTLV-1-associated diseases, especially following infection in infancy, requires strong action to reduce vertical transmission. METHODS: To facilitate the appraisal of the implementation of the HTLV antenatal screening program by the Brazilian Ministry of Health, we determined the costs in distinct scenarios according to HTLV seroprevalence, specificity of the screening test, and type of confirmatory test. RESULTS: HTLV antenatal screening would cost R$ 55,777,012-R$ 77,082,123/year. Screening assays with high specificity reduce the need and cost of confirmatory assays by up to 25%. CONCLUSIONS: Careful selection of the screening assay is required to optimize the program.

Prevalence of infection by human T Cell lymphotropic viruses (HTLV-1/2) in adult population in Vitoria-ES

ABSTRACT Introduction: Brazil has a high number of HTLV-1/2 infections which are unequally distributed in the country. Most prevalence studies have focused on specific populations, such as blood donors and pregnant women. Some areas, for example the state of Bahia, have robust information about HTLV-1/2 infection, however there is no information available about this infection in the general population of Vitoria, Espírito Santo, Brazil. Objective: To determine the prevalence of HTLV-1/2 infection in adults from the municipality of Vitoria, ES. Methods: A cross sectional study was performed from September 2010 to December 2011, in individuals of both sexes, aged 18 or older living in Vitoria-ES. Venous blood samples were collected and tested for anti-HTLV-1/2 antibodies by chemiluminescent immunoassay (CMIA). Individuals with CMIA reactive results were submitted to a new blood collection for retesting by CMIA, followed by PCR to confirm infection and discriminate the viral type. Results: From 1502 tested samples, eight were reactive in CMIA and all were confirmed by PCR. Therefore, the prevalence of HTLV-1/2 was 0.53% (8/1502, 95% CI: 0.2-1.0%). The infection rate was 0.7% in men (5/711, 95% CI: 0.17-1.51%), and 0.38% in women (3/791, 95% CI: 0 -0.81%). Conclusions: The prevalence of HTLV-1/2 infection was 0.53% (8/1502; 95% CI: 0.2 -0.9%). Confirmatory test using real-time PCR (qPCR) identified seven individuals positive for HTLV-1 and one for HTLV-2. Considering the risk of infected individuals to develop high morbidity and mortality diseases, it would be important to implement public health policies aimed at stopping transmission of these viruses in this municipality. 2021 Sociedade Brasileira de Infectologia. Published by Elsevier España, S.L.U. This is an open access article under the CC BY-NC-ND license

Pain in tropical spastic paraparesis/HTLV-I associated myelopathy patients / Dor em pacientes com paraparesia espástica tropical/mielopatia associada ao HTLV-I

OBJECTIVE: Tropical Spastic Paraparesis/HTLV-I Associated Myelopathy (TSP/HAM) is a chronic myelopathy, and pain has been mentioned as a frequent sensory symptom in this condition. The authors aimed at analyzing this symptom in a TSP/HAM patients series. METHOD: For this, 46 patients were analyzed considering demographic and clinical characteristics and complaint of pain as to verbal description, time of onset and classification, correlated with the degree of motor disability and type of pain. RESULTS: Among the 46 TSP/HAM patients, 28 (60.8 percent) complained of pain, predominant in the early phase of the disease. Most of the patients exhibited neuropathic characteristics of pain, correlated with increased motor disability. CONCLUSION: Pain in TSP/HAM patients is a frequent and early symptom, and the neuropathic type is predominant (57.1 percent) and paralleled with increased incapacitation. The pathogenic involvement of cytokines may possibly be involved in the meaning of this symptom in this condition.

OBJETIVO: A Paraparesia Espástica Tropical/Mielopatia Associada ao HTLV-I (PET/MAH) é uma mielopatia crônica, e a dor tem sido mencionada como um sintoma sensitivo freqüente nessa condição. Os autores objetivam analisar esse sintoma numa série de pacientes com PET/MAH. MÉTODO: Para isso, 46 pacientes foram analisados considerando características demográficas e clínicas, e queixa de dor do ponto de vista da descrição verbal, tempo de início e classificação, correlacionados com o grau de incapacitação motora e o tipo de dor. RESULTADOS: Dentre os 46 pacientes com PET/MAH, 28 (60,8 por cento) se queixavam de dor, predominando na fase inicial da doença. A maioria dos pacientes evidenciou características de dor neuropática, correlacionada com aumento da incapacitação motora. CONCLUSÃO: A dor em pacientes com PET/MAH é um sintoma freqüente e inicial, sendo o tipo neuropático predominante (57,1 por cento) e em paralelo com maior incapacitação. O envolvimento patogênico das citocinas poderá possivelmente estar relacionado com o significado desse sintoma nessa condição clínica.

Identification of the major allergens of Indian scad (Decapterus russelli).

The purpose of this study was to characterize major allergens of Indian scad (Decapterus russelli) which is among the most commonly consumed fish in Malaysia. Raw and cooked extracts of the fish were prepared. Protein profiles and IgE binding patterns were produced by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and immunoblotting using sera from subjects with fish allergy. The major allergens of the fish were then identified by two-dimensional electrophoresis (2-DE), followed by mass spectrometry of the peptide digests. The SDS-PAGE of the raw extract revealed 27 protein fractions over a wide molecular weight range, while the cooked extract demonstrated only six protein fractions. The 1-DE immunoblotting detected 14 IgE-binding proteins, with a molecular weight range from 90 to < 6.5 kDa. Three protein fractions with molecular weights of approximately 51, 46 and 12 kDa were identified as the major allergens of this fish. The approximately 12 kDa band was a heat-resistant protein while the approximately 51 and 46 kDa proteins were sensitive to heat. The 2-DE gel profile of the raw extract demonstrated > 100 distinct protein spots and immunoblotting detected at least 10 different major IgE reactive spots with molecular masses as expected and isoelectric point (pI) values ranging from 4.0 to 7.0. A comparison of the major allergenic spot sequences of the 12 kDa proteins with known protein sequences in databases revealed extensive similarity with fish parvalbumin. In conclusion, this study demonstrated that a parvalbumin which is similar to Gad c 1 is the major allergen of Indian scad. Interestingly, we also detected heat-sensitive proteins as major allergenic components in our fish allergy patients.