Clinical symptoms and the odds of human T-cell lymphotropic virus type 1–associated myelopathy/ tropical spastic paraparesis (HAM/TSP) in healthy virus carriers: Application of best-fit logistic regression equation based on host genotype, age, and provirus load

Abstract

The authors have previously developed a logistic regression equation to predict the odds that a human T-cell lymphotropic virus type 1 (HTLV-1)-infected individual of specified genotype, age, and provirus load has HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) in southern Japan. This study evaluated whether this equation is useful predictor for monitoring asymptomatic HTLV-1-seropositive carriers (HCs) in the same population. The authors genotyped 181 HCs for each HAM/TSP-associated gene (tumor necrosis factor [TNF]-alpha-863A/C, stromal cell-derived factor 1 (SDF-1) +801G/A, human leukocyte antigen [HLA]-A*02, HLA-Cw*08, HTLV-1 tax subgroup) and measured HTLV-1 provirus load in peripheral blood mononuclear cells using real-time polymerase chain reaction (PCR). Finally, the odds of HAM/TSP for each subject were calculated by using the equation and compared the results with clinical symptoms and laboratory findings. Although no clear difference was seen between the odds of HAM/TSP and either sex, family history of HAM/TSP or adult T-cell lenkemia (ATL), history of blood transfusion, it was found that brisk patellar deep tendon reflexes, which suggest latent central nervous system compromise, and flower cell-like abnormal lymphocytes, which is the morphological characteristic of ATL cells, were associated with a higher odds of HAM/TSP. The best-fit logistic regression equation may be useful for detecting subclinical abnormalities in HCs in southern Japan.

Evaluation of host genetic and viral factors as surrogate markers for HTLV‐1‐associated myelopathy/tropical spastic paraparesis in Peruvian HTLV‐1‐infected patients

“…The discrepancies between our and previous reports [Jeffery et al, 1999[Jeffery et al, , 2000Furukawa et al, 2000;Nose et al, 2006] may be due to the fact that the host genetic factors studied might not be involved in the etiology of HAM/TSP across all populations. In this aspect, it is worthwhile noting that our study was in agreement with an Iranian study [Sabouri et al, 2005].…”

HTLV-1-associated myelopathy/tropical spastic paraparesis

“…However, application of these risk factors and clinical or laboratory features has not proved helpful in making a diagnosis in individual cases. In a Japanese analysis, the only clinical correlates of the diagnosis of HAM/TSP were detection of brisk patellar tendon reflexes, which might reflect subclinical disease, and the presence of 'flower cells' 113 (HTLV-1-infected lymphocytes with a characteristic multilobular nucleus, Figure 6). Atypical lymphocytes with an abnormal nuclear morphology can be observed in people with any clinical manifestation of HTLV-1 infection; their presence is associated with inflammation rather than with a higher risk of ATL 114 .…”

Fucoidan Therapy Decreases the Proviral Load in Patients with Human T-Lymphotropic Virus Type-1-Associated Neurological Disease

“…Several virological and immunological parameters have been identified as potential markers of disease activity in HAM/TSP [5,7,24,25]. The HTLV-1 proviral DNA load is one of the most important pathogenic factors in HAM/TSP, and is correlated with the risk of HAM/TSP and ATL in asymptomatic carriers of HTLV-1 infection [25][26][27]. Therefore, the major purpose of this study was to examine the potential of fucoidan for decreasing the HTLV-1 proviral load in HTLV-1-infected individuals.…”