Central Nervous System Idiopathic Inflammatory Demyelinating Disorders in South Americans: A Descriptive, Multicenter, Cross-Sectional Study.

The idiopathic inflammatory demyelinating disease (IIDD) spectrum has been investigated among different populations, and the results have indicated a low relative frequency of neuromyelitis optica (NMO) among multiple sclerosis (MS) cases in whites (1.2%-1.5%), increasing in Mestizos (8%) and Africans (15.4%-27.5%) living in areas of low MS prevalence. South America (SA) was colonized by Europeans from the Iberian Peninsula, and their miscegenation with natives and Africans slaves resulted in significant racial mixing. The current study analyzed the IIDD spectrum in SA after accounting for the ethnic heterogeneity of its population. A cross-sectional multicenter study was performed. Only individuals followed in 2011 with a confirmed diagnosis of IIDD using new diagnostic criteria were considered eligible. Patients' demographic, clinical and laboratory data were collected. In all, 1,917 individuals from 22 MS centers were included (73.7% female, 63.0% white, 28.0% African, 7.0% Mestizo, and 0.2% Asian). The main disease categories and their associated frequencies were MS (76.9%), NMO (11.8%), other NMO syndromes (6.5%), CIS (3.5%), ADEM (1.0%), and acute encephalopathy (0.4%). Females predominated in all main categories. The white ethnicity also predominated, except in NMO. Except in ADEM, the disease onset occurred between 20 and 39 years old, early onset in 8.2% of all cases, and late onset occurred in 8.9%. The long-term morbidity after a mean disease time of 9.28±7.7 years was characterized by mild disability in all categories except in NMO, which was scored as moderate. Disease time among those with MS was positively correlated with the expanded disability status scale (EDSS) score (r=0.374; p=<0.001). This correlation was not observed in people with NMO or those with other NMO spectrum disorders (NMOSDs). Among patients with NMO, 83.2% showed a relapsing-remitting course, and 16.8% showed a monophasic course. The NMO-IgG antibody tested using indirect immunofluorescence (IIF) with a composite substrate of mouse tissues in 200 NMOSD cases was positive in people with NMO (95/162; 58.6%), longitudinally extensive transverse myelitis (10/30; 33.3%) and bilateral or recurrent optic neuritis (8/8; 100%). No association of NMO-IgG antibody positivity was found with gender, age at onset, ethnicity, early or late onset forms, disease course, or long-term severe disability. The relative frequency of NMO among relapsing-remitting MS (RRMS) + NMO cases in SA was 14.0%. Despite the high degree of miscegenation found in SA, MS affects three quarters of all patients with IIDD, mainly white young women who share similar clinical characteristics to those in Western populations in the northern hemisphere, with the exception of ethnicity; approximately one-third of all cases occur among non-white individuals. At the last assessment, the majority of RRMS patients showed mild disability, and the risk for secondary progression was significantly superior among those of African ethnicity. NMO comprises 11.8% of all IIDD cases in SA, affecting mostly young African-Brazilian women, evolving with a recurrent course and causing moderate or severe disability in both ethnic groups. The South-North gradient with increasing NMO and non-white individuals from Argentina, Paraguay, Brazil and Venezuela confirmed previous studies showing a higher frequency of NMO among non-white populations.

Mielopatia associada ao HTLV-I: aspectos relacionados à infância / HTLV-I associated myelopathy: aspects related to childhood

A mielopatia associada ao HTLV-I ou paraparesia espástica tropical (HAM/TSP) é caracterizada por uma paraparesia espástica lentamente progressiva associada a disfunções esfincterianas e sensitivas. A enfermidade acomete indivíduos na faixa etária dos 30 aos 50 anos, sendo um diagnóstico negligenciado em crianças que se apresentam com paraparesia espástica de curso evolutivo. O presente estudo propõe uma revisão dos aspectos clínicos e epidemiológicos relacionados à HAM/TSP, suas principais formas de transmissão e os critérios para o diagnóstico em crianças com queixas neurológicas sugestivas.O conhecimento detalhado dos aspectos clínicos e laboratoriais que definem tal condição na infância e na adolescência contribui para o diagnóstico precoce desta enfermidade neurológica incapacitante.

The HTLV-I-associated myelopathy or tropical spastic paraparesis (HAM/TSP) is characterized by a slowly progressive spastic paraparesis associated with sphincter and sensory dysfunction. The disorder usually affects people aged from 30 to 50 years. This diagnosis is neglected by many clinicians in children who present with spastic paraparesis of progressive course. This study proposes a revision of clinical and epidemiological aspects related to HAM/TSP in children, their main mechanisms of transmission and the diagnosis criteria with suggestive neurological complaints. The detailed knowledge of clinical and laboratory that define this condition in childhood and adolescence will help to early diagnosis of this disabling neurological illness.