Manifestations of the human T-cell lymphotropic virus type I infection in childhood and adolescence

Abstract

Objectives: To review the literature on diseases linked with infection by human T-cell lymphotropic virus type I (HTLV-I) in childhood and adolescence, with focus on clinical aspects, diagnosis, pathogenesis, progression and treatment.Sources: Medical literature published during the last 20 years identified using PubMed and MEDLINE and from specialized medical books, with emphasis on infective dermatitis associated with HTLV-I (IDH), on the juvenile form of HTLV-associated myelopathy/tropical spastic paraparesis (HAM/TSP), on adult T-cell leukemia/lymphoma (ATL) and on HTLV-I-associated uveitis. Keywords used to search databases were: HTLV-I-associated infective dermatitis, HTLV-Iassociated myelopathy/tropical spastic paraparesis, adult T-cell leukemia/lymphoma, HTLV-I-associated uveitis.Summary of the findings: IDH is a chronic, relapsing and infected dermatitis of childhood which always involves the scalp and which may progress to HAM/TSP and ATL. HAM/TSP is a chronic and incapacitating myelopathy of adults. There are 17 well-documented cases of HAM/TSP in children and adolescents in the literature, 12 of whom are patients with IDH. In contrast with the adult form of the disease, the juvenile form is rapid and progressive. ATL is a type of T-cell leukemia/ lymphoma that affects adults and is generally fatal. Eleven of the 24 published reports of ATL in children and adolescents were diagnosed in Brazil.Conclusions: These diseases are likely to be more common in childhood and adolescence than the literature would suggest. It is advisable that serological testing be performed for HTLV-I in children and adolescents suffering from chronic and relapsing eczema, with signs and symptoms of myelopathy or with a diagnosis of T-cell leukemia/lymphoma. It is important that pediatricians know how to recognize the pediatric manifestations of this infection in order to correctly diagnose them and offer their patients appropriate guidance and treatment.

Adult T-Cell Leukemia/Lymphoma

“…Most common organ involvement in children is skin, followed by lymph nodes, liver, and spleen. 4 PATHOGENESIS HTLV-1 was the first human retrovirus to be identified. 15 Within infected cells, the single-stranded RNA virus is converted to proviral DNA and then integrated into host DNA by viral integrase.…”

“…2 The lifelong viral carrier state and long latency (20-40 years) exist after HTLV-1 infection; therefore, the lymphoma is exclusively found in the adult population and is extremely rare in children (,25 cases reported). [2][3][4] The lifetime risk of progression to ATLL in an HTLV-1-positive patient is 2.1% for women and 6.6% for men. 5 The mean age of onset is 60 years (range, 20-80 years), with a slight male predilection (male to female ratio, 1.5:1).…”

Adult T-cell leukemia/lymphoma (ATL) presenting in the skin: Clinical, histological and immunohistochemical features of 52 cases

“…However IDH is a severe and infected dermatitis that occurs in childhood. Besides there is a juvenile form of HAM/TSP and even ATL may occur earlier, in adolescence or in early adulthood [8].ATL is an aggressive mature T-cell malignancy that affects the skin in 43Á72% of cases [9].…”

Manifestações cutâneas da infecção e das doenças relacionadas ao vírus linfotrópico de células T humanas do tipo 1

“…23 A maior parte dos casos ocorre na Jamaica, 24 no Brasil e, em menor número, no Peru, Senegal e em Trinidad e Tobago. 25,26 No Japão, país com elevada prevalência da infecção pelo HTLV-1, foram relatados poucos casos da DI. Fatores genéticos ou socioeconômicos poderiam ser responsáveis por essa observação.…”