Differentiation of HAM/TSP from patients with multiple sclerosis infected with HTLV-I.
OBJECTIVE
To better differentiate patients with human T lymphotropic virus type I (HTLV-I)-associated myelopathy/tropical spastic paraparesis (HAM/TSP) from patients with multiple sclerosis (MS) who are HTLV-I seropositive, we compared the HTLV-I antibodies and HTLV-I proviral DNA loads in CSF and peripheral blood mononuclear cells (PBMC).


METHODS
Intrathecal synthesis of HTLV-I antibodies and HTLV-I proviral DNA loads in CSF and PBMC were measured and compared in 39 Brazilian patients: 17 HAM/TSP and 22 HTLV-I-seropositive non-HAM/TSP (7 with other neurologic diseases, 11 asymptomatic carriers, and 4 HTLV-I-seropositive patients with an MS-like phenotype). In addition, we followed immunologic and virologic markers in comparison to the clinical course (by Kurtzke Expanded Disability Status Scale) of seven patients (five with HAM/TSP and two with an MS-like phenotype) for a mean period of 16 (SD +/- 5) months.


RESULTS
The proviral load in CSF and PBMC was higher in HAM/TSP than in non-HAM/TSP patients, except in the two HTLV-I-seropositive patients with an MS-like phenotype that also fulfilled the criteria for HAM/TSP. Higher HTLV-I proviral DNA load in CSF was associated with the higher proviral DNA load in PBMC and lower intrathecal synthesis of HTLV-I antibodies. These laboratory findings remained stable during follow-up.


CONCLUSIONS
The high proviral load in peripheral blood mononuclear cells or in CSF or both may be a good marker of human T lymphotropic virus type I (HTLV-I)-associated myelopathy/tropical spastic paraparesis (HAM/TSP) and can differentiate patients with HAM/TSP from patients with multiple sclerosis infected with HTLV-I.
Puccioni-Sohler
M
M
Neurological Service, Gaffree Guinle University Hospital, Federal University of Rio de Janeiro State, Rio de Janeiro, Brazil. mpuccioni@hucff.ufrj.br
Yamano
Y
Y
Rios
M
M
Carvalho
S M F
SM
Vasconcelos
C C F
CC
Papais-Alvarenga
R
R
Jacobson
S
S
D000328:Adult; D003937:Diagnosis, Differential; D005260:Female; D015368:Human T-lymphotropic virus 1 / Q000302:isolation & purification*; D006801:Humans; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000175:diagnosis* / Q000821:virology*; D015493:Paraparesis, Tropical Spastic / Q000175:diagnosis* / Q000821:virology*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D019562:Viral Load / Q000379:methods*