# Neurological Signs and Symptoms in Human T-Lymphotropic Viruses 1 and 2 Infected Patients Living in the Amazon Region, Northern Brazil

## TL;DR

This study examines neurological symptoms in people infected with HTLV-1 and HTLV-2 in the Amazon region of Brazil, finding that many experience motor and urinary issues, which may serve as early warning signs.

## Contribution

The study reports new neurological manifestations in HTLV-1 and HTLV-2 infections, including cranial nerve and upper limb involvement, and identifies urinary symptoms as potential early markers.

## Key findings

- Neurological symptoms were present in 86.7% of HTLV-infected patients, including spasticity and chronic pain.
- Urinary symptoms were observed in 77% of symptomatic patients and may act as sentinel symptoms for neurological impairment.
- Cranial nerve and upper limb involvement were reported, which are rarely described in HTLV literature.

## Abstract

HTLV-1 and HTLV-2 infections are associated with various neurological manifestations, particularly HTLV-1-associated myelopathy (HAM). This descriptive, cross-sectional observational study aimed to investigate and analyze the neurological manifestations in patients treated at the Service for the Care of People Living with HTLV (Serviço de Atendimento à Pessoa Vivendo com HTLV-SAPEVH) at the Federal University of Pará. A cohort of 957 individuals underwent screening for HTLV-1/2 infection using enzyme-linked immunosorbent assay (ELISA), with seropositive samples subsequently confirmed via Western blotting or quantitative polymerase chain reaction (qPCR). HTLV-1/2 infection was confirmed in 69 individuals. Of these, fifteen individuals—diagnosed with HTLV-1 (n = 11) or HTLV-2 (n = 4) infection—who presented with neurological complaints at the first nursing consultation, were referred to a neurologist for clinical evaluation of neurological signs and symptoms. Most of the patients were female (13), ranging from 33 to 80 years of age. Neurological symptoms were present in 86.7%, and included spasticity, paraparesis, chronic pain, both motor and sensory deficits, as well as urinary disorders, predominantly affecting the thoracic spinal cord and lower limbs. Urinary symptoms were observed in 77% of symptomatic patients, often preceding other neurological signs that suggest a role as “sentinel symptoms” in the clinical screening of HTLV carriers. The results demonstrated the presence of neurological impairment in patients infected with both HTLV-1 and HTLV-2, with motor symptoms ranging from moderate to advanced. In addition, cases of cranial nerve and upper limb involvement were reported, a finding that is rarely described in the literature. The study highlights the importance of neurological assessment as early as possible in patients infected with either HTLV-1 or HTLV-2 and suggests that sphincter dysfunctions can serve as early clinical markers of future neurological impairment.