Sindromes paraneoplásicas Flashcards
Quais os três principios das síndromes paraneoplasicas?
First, it is common for symptoms to appear before the presence of a tumor is known; second, the neurologic syndrome usually develops rapidly, producing severe deficits in a short period of time; and third,here is evidence that prompt tumor control improves the neurologic outcome. Therefore, the major concern of the physician is to recognize a disorder promptly as paraneoplastic to identify and treat the tumor.
Quais os exames fundamentais na investigação de síndromes paraneoplasicas?
(1) The clinical history, accompanying symptoms (e.g., anorexia, weight loss)
(2) MRI and CSF studies are important to rule out neurologic complications due to the direct spread of cancer, particularly metastatic and leptomeningeal disease
(3) The presence of antineuronal antibodies may help in the diagnosis, but only 60–70% of PNDs of the CNS and less than 20% of those involving the peripheral nervous system have neuronal or neuromuscular antibodies that can be used as diagnostic tests. In paraneoplastic neuropathies, diagnostically useful antineuronal antibodies are limited to anti-CV2/CRMP5 and anti-Hu.
(4) Chest and abdomen CT or body positron emission tomography (PET) scan and, if negative, periodic tumor screening for at least 3 years after the neurologic diagnosis. Serum and urine immunofixation studies should be considered in patients with peripheral neuropathy of unknown cause; detection of a monoclonal gammopathy suggests the need for additional studies to uncover a B cell or plasma cell malignancy. For germ-cell tumors of the testis and teratomas of the ovary ultrasound and MRI may reveal tumors undetectable by PET.
Qual o manejo da encefalite paraneoplasica?
(1) Most types of paraneoplastic encephalitis and encephalomyelitis respond poorly to treatment. Approximately 30% of patients with anti-Ma2-associated encephalitis respond to treatment of the tumor (usually a germ-cell neoplasm of the testis) and immunotherapy
(2) Stabilization of symptoms or partial neurologic improvement may occasionally occur, particularly if there is a satisfactory response of the tumor to treatment.
(3) The roles of plasma exchange, intravenous immunoglobulin (IVIg), and immunosuppression have not been established.
Qual o manejo da polineuropatia paraneoplasica?
(1) As with anti-Hu-associated encephalomyelitis, the therapeutic approach focuses on prompt treatment of the tumor.
(2) Glucocorticoids occasionally produce clinical stabilization or improvement. The benefit of IVIg and plasma exchange is not proved.
Opsoclonus-mioclonus e tipicamente um achado paraneoplasico. Qual a conduta?
Opsoclonus is a disorder of eye movement characterized by involuntary, chaotic saccades that occur in all directions of gaze; it is frequently associated with myoclonus and ataxia. Opsoclonus-myoclonus may be cancerrelated or idiopathic. When the cause is paraneoplastic, the tumors involved are usually cancer of the lung and breast in adults and neuroblastoma in children. The pathologic substrate of opsoclonus-myoclonus is unclear, but studies suggest that disinhibition of the fastigial nucleus of the cerebellum is involved. Most patients do not have detectable antineuronal antibodies. A small subset of patients with ataxia, opsoclonus, and other eye-movement disorders develop anti-Ri antibodies; in rare instances muscle rigidity, autonomic dysfunction, and dementia also occur.
(1) The tumors most frequently involved in anti-Ri-associated syndromes are breast and ovarian cancer. If the tumor is not successfully treated, the neurologic syndrome in adults often progresses to encephalopathy, coma, and death.
(2) In addition to treating the tumor, symptoms may respond to immunotherapy (glucocorticoids, plasma exchange, and/or IVIg).
Quais as principais síndromes paraneoplasicas?
(1) cortical encephalitis, which may present as “epilepsia partialis continua”; (2) limbic encephalitis, characterized by confusion, depression, agitation, anxiety, severe short-term memory deficits, partial complex seizures, and sometimes dementia (the MRI usually shows unilateral or bilateral medial temporal lobe abnormalities, best seen with T2 and fluid-attenuated inversion recovery sequences, and occasionally enhancing with gadolinium); (3) brainstem encephalitis, resulting in eye movement disorders (nystagmus, opsoclonus, supranuclear or nuclear paresis), cranial nerve paresis, dysarthria, dysphagia, and central autonomic dysfunction; (4) cerebellar gait and limb ataxia; (5) myelitis, which may cause lower or upper motor neuron symptoms, myoclonus, muscle rigidity, and spasms; and (6) autonomic dysfunction as a result of involvement of the neuraxis at multiple levels, including hypothalamus, brainstem, and autonomic nerves (see autonomic neuropathy).
Quais as três características das encefalites com anticorpos anti-neurais positivos?
These disorders are important for three reasons: (1) they can occur with and without tumor association, (2) some syndromes predominate in young individuals and children, and (3) despite the severity of the symptoms, patients usually respond to treatment of the tumor, if found, and immunotherapy (glucocorticoids, plasma exchange, IVIg, rituximab, or cyclophosphamide).
