Dados do Trabalho

Título

Severe toxic and immune sensory-cerebellar ataxia in an oncologic patient

RESUMO

A 73-year-old female patient presents with progressive worsening of gait in the last 6 months, rangin from walking without devices to using a wheelchair in 3 months. Besides chronic type 2 diabetes, she also had a history of breast and ovarian cancer diagnosed in the last 5 years, both with surgical and chemotherapy treatment. On admission, the patient had preserved strength, pseudoathetotic movements in the fingers of the hands, severe sensory impairment composed by hypopalesthesia in all four limbs, worse in the legs, and proprioceptive dysfunction of the halluxes. She had scanning speech and bidirectional horizontal nystagmus accompanied by hypometric saccades with corrective movements. Axial and appendicular ataxia shown as the inability to remain seated without aid and dysmetria in all four limbs, markedly worse when eyes are closed. In orthostasis, she showed abasia accompanied by extremely cautious gait and Romberg's sign. Cranial magnetic resonance imaging revealed marked cerebellar atrophy and electroneuromyography showed severe sensory and motor neuropathy in the 4 limbs. Cerebrospinal fluid (CSF) with 1 leukocyte and 65mg/dL proteins. Vitamin dosages and inflammatory markers without alterations. The autoimmunity test was positive for anti-Yo in CSF and blood samples, with titers of 1:256 and 1:15360, respectively. After receiving 1 g of Methylprednisolone per day for 5 days, the patient had a slight improvement in ataxia and was discharged for outpatient follow-up.

Neurotoxicity is a common side effect in patients undergoing chemotherapy, with peripheral nerves being more affected than the central nervous system. Toxicity is usually worse for sensory fibers, generating paresthesias or proprioceptive deficits when thick fibers are affected. In this same context, neuronal death can also be induced by paraneoplastic syndromes, which are mediated by antibodies produced by immune activation in response to cancer. Among them, Paraneoplastic Cerebellar Degeneration mediated by anti-Yo (also known as anti-Purkinje cell cytoplasmic antibody type-1) stands out, an antibody specifically directed to the cerebellum responsible for generating an ataxic syndrome.

Ataxia and sensory changes are common findings in cancer patients and may have a multifactorial origin. The final outcome can be influenced by previous pathologies, chemotherapeutic-induced toxicity and even autoimmunity in a context of paraneoplastic syndrome.