associated myelopathy in Argentina
FURTHER STUDIES ON HTLV-I ASSOCIATED MYELOPATHY IN ARGENTINA
LEONARDO A. GONZALEZ, ANDRES M. VILLA, GUILLERMO KOHLER, ORLANDO GARCEA, MARCELO KREMENCHUTZKY, FERNANDO CACERES, OLGA P. SANZ, ROBERTO E. P. SICA
División Neurología, Hospital Ramos Mejía, Buenos Aires
Key words: HTLV-I associated myelopathy, tropical spastic paraparesis.
We report 10 HTLV-I virus seropositive subjects, eight of them with HTLV-I associated myelopathy (HAM), two of them also infected with HIV as well as two asymptomatic HTLV-I+ relatives of two unrelated patients. HTLV-I is endemic in several tropical areas, where it causes different neurological diseases. Only few patients have been reported in our country since 1994. We studied 8 patients, who fulfilled the clinical criteria for chronic spastic paraplegia, and 2 other non-symptomatic HTLV-I seropositive relatives, with electromyography (EMG), motor and sensory conduction velocities (NCV), somatosensory, visual and brainstem auditory evoked potentials (SSEP, VEP and BAEP), Magnetic Resonance Images (MRI) and cerobrospinal fluid (CSF) analysis. The latter was carried out only in seven symptomatic patients. In every case positive ELISA tests for HTLV-I/II were confirmed by Western Blot. The two asymptomatic persons were clinically and electromyographically assessed, one of them was also submitted to SSEPs studies. Three patients were males. Patient’s ages ranged from 5 to 65 years old. All symptomatic patients showed muscular weakness, spasticity with pyramidal signs and sphincter disturbances. Five of them had paresthesias and 2 had burning pain on their feet. The EMGs and the NCVs were normal in 7 patients and in the 2 asymptomatic ones. SSEPs, obtained by stimulating the posterior tibial nerves, were impaired in 7 patients and in the asymptomatic person who received the procedure. The 7 symptomatic patients who underwent lumbar puncture had positive tests for HTLV-I in CSF, 3 out of these 7 patients had also high protein levels and 4 had increased number of lymphocytes. In 2 patients intrathecal IgG production could also be demonstrated. MRI were normal in 7 patients and in the 2 asymptomatics, the exception being a female who had bilateral hyperintense lesions in cerebral white matter in T2. In conclusion, tropical spastic paraparesis is apparently a rare disorder in Argentina. However, some cases have been reported recently. Most probably, its prevalence is currently underestimated. Its diagnosis should be considered in every patient with progressive spastic paraplegia.
Nuevos estudios sobre mielopatía asociada a HTLV-I en la Argentina. Presentamos 10 pacientes con serología positiva para HTLV-I, 8 de ellos con mielopatía asociada a HTLV-I (HAM), incluyendo 2 HIV positivos. El HTLV-I es endémico en varias áreas tropicales, donde es responsable de diferentes patologías. En nuestro país fueron comunicados unos pocos pacientes desde 1994 (Garcea et al 1994; Gutfraind et al 1995; Micheli et al 1996). Estudiamos 8 pacientes con paraplejía crónica progresiva, y dos familiares directos seropositivos asintomáticos, con electromiografía (EMG), velocidades de conducción motora y sensitiva (VC), potenciales evocados somatosensitivos, visuales y auditivos (PESS, PEV y PEAT), Imágenes de Resonancia Magnética (IRM) y estudio del líquido cefalorraquídeo (LCR). La punción lumbar (PL) fue hecha sólo en 7 de los 8 pacientes sintomáticos. Todos los resultados de ELISA positivos para el HTLV-I fueron confirmados con Western Blot. Tres pacientes eran hombres. Los pacientes tenían entre 5 y 65 años de edad. Todos los pacientes sintomáticos presentaban debilidad muscular, espasticidad, piramidalismo y trastornos esfinterianos. Cinco tenían parestesias y 2 dolor urente en los pies. Los EMGs y VCs fueron normales en 9, mientras que los PESS estimulando los nervios tibiales posteriores fueron anormales en 8 pacientes. Los 7 pacientes sintomáticos a los que se les realizó PL tuvieron serología positiva para HTLV-I en LCR, en 3 de ellos se demostró hiperproteinorraquia y en 4 pleocitosis linfocítica. Además, en 2 se pudo demostrar la producción intrathecal de IgG. Las IRM fueron normales en 9 pacientes, siendo la excepción una paciente con imágenes hiperintensas en sustancia blanca en secuencias de T 2. En conclusión, la paraparesia espástica tropical es aparentemente una enfermedad rara en nuestro país. Aunque últimamente se han estado comunicando algunos casos, probablemente su prevalencia es subestimada. Destacamos la importancia de la inclusión de este diagnóstico en todo paciente con paraplejía espástica progresiva.
Postal address: Dr. Roberto E. P. Sica, División Neurología, Hospital Ramos Mejía, Urquiza 609, 1221 Buenos Aires, Argentina. Fax: 54-1-962-2022
Received: 31-III-1998 Accepted: 3-VI-1998
Chronic progressive myelopathy is defined as a para-plegia with gradual onset and variable levels of sensory loss and sphincter disturbances, without evidences of lower motor neuron involvement, spinal cord com-pression, or supramedullary disseminated lesions1-5. This disease has usually been reported in high HTLV-I endemic areas; mainly the Caribbean, Southern Japan, Central and South America6-11. In Argentina, as far as we know, surveys done in blood donors in Buenos Aires yielded a low prevalence, similar to that of non ende- mic countries12, 13. We report our experience in 8 cases of slowly progressing spastic paraplegia, with positive HTLV-I antibodies in sera and cerebrospinal fluid (CSF) and in two non-symptomatic relatives, also infected with the mentioned retrovirus. Because in Argentina, HAM/TSP is not a frequently reported illness14, 15, the aim of this work is to present epidemiologic data and the clinical features, the neurophysiology, the imaging and the CSF findings in this group of patients.
Material and Methods
Altogether we studied 8 patients, 6 females and 2 males, aged
between 24 and 65 years, who fulfilled the clinical criteria for
chronic spastic paraplegia (#1 to #8). Once the diagnosis was made, we
summoned the patient’s relatives and made a serological screening
looking for HTLV-I subclinical infection. We could only assess 4
relatives and found two of them (#9 and #10) who disclosed positive
serological tests. Those two persons were investigated through
clinical and laboratory studies and included within this
communication. The rational for doing this is to show that some
findings can be achieved in people who may have the infection but
remain clinically asymptomatic.
Epidemiologic data: Three patients were from northern provinces,
located within the subtropical regions of the Country, 5 patients were
in downtown Buenos Aires and currently living in the city. Two
patients were also infected with HIV, (intravenous drug abusers).
Another patient had had blood transfusion several years before the
beginning of the symptoms. Two out of the four relatives investigated
had positive serological tests, and were the wife and one son of two
different symptomatic patients; these two persons were born in Buenos
Aires and lived there at the time of their assessment.
As previously described in the literature5 our patients had the
typical clinical picture of gradual onset spastic paraplegia with
pyramidal signs, developing, in the course of the illness, sphincter
disturbances. Intrathecal IgG synthesis and elevated IgG index have
been described in most patients reported in the literature17, 18; we
could document these features only in 2 subjects of our se-ries.
Peripheral nervous system involvement has been described in the
literature in about 25% of the pa- tients5, 19, in our series we only
found one patient with focal abnormal NCVs studies in one of her lower
limbs. In the literature, abnormal VEP latencies were seen in 30% of
the patients, and BAEPs prolonged latencies were also found in 25% of
them5, 20. We found only one patient with abnormal VEPs latencies and
2 who showed abnormal BAEPs.
1. Osame M, Usuku K, Izumo S, Ijichi N, Amitani HI, Gata A, et al.
HTLV-I associated myelopathy, a new clinical entity (Letter). Lancet
1986; 1: 1031-2.
Patient Onset Time from Paraparesis ASS. Sph. D. Sen. D. Pain
#1 RL 5 years Moderate 4/5 Yes No No
RL: right leg; LL: left leg; ASS: Aschworth spasticity score;
N (ms) P (ms) Ampl (µV)
#1 49 53 1,5
Normal ranges: N: 32-34 ms; P: 40-42 ms; Ampl: > 1,25 µV