spontaneous remission of anti-Ma associated paraneoplastic mesodiencephalic and brainstem encephalitis

Case Details

Disease Location

Left mesencephalon and diencephalon

Personal Characteristics

39 -year-old female

Clinical Characteristics

Presented with diplopia. MRI found enhancing lesions of the left mesencephalon and diencephalon. Lumbar puncture was normal one months later, MRI showed marked extension of the lesions. Csf showed slightly elevated protein ad mild pleocytosis. Patient had blurred vision and severe bilateral headaches. Muscle tone, power, and sensation were normal. Arm reflexes were normal, leg reflexes were hyperactive with clonus. Pupillary responses were intact. There was bilateral gaze-evoked nystagmus, and eye fixation revealed skew deviation. Smooth pursuit showed saccadic movement. Vestibulo-ocular reflexes were intact. There was marked short-term memory impairment. No blood or urine abnormalities. One IGG band was found in the csf but not in serum, cytology was negative for malignant cells. MRI found diffuse mesodiencephalic abnormalities with nodular contrast enhancement. Screening for onconeuronal antibodies found anti-pnma2 and anti-pnma1. Positive titer and MRI findings suggested a paraneoplastic syndrome, endoscopy included biopsies, abdominal ultrasonogram, mammography, genitourinary ad skin exams. Repeated body cts revealed no neoplastic changes. Control lumbar puncture revealed multiple oligoclonal bands. Whole body fdg-PET showed an area of hypermetabolism in the left lung, thin section CT failed to show a corresponding lung mass and bronchoscopy was normal despite findings, surgery was held off 6 weeks later, neurological symptoms were unchanged except the headaches were considerably reduced. Thoracic CT revealed no lung mass 4 months later, MRI showed complete remission of mesodiencephalic encephalitis

Remission Characteristics

4 months later, MRI showed complete remission of mesodiencephalic encephalitis, PET no long revealed area of hypermetabolism between 10 and 19 months, neurological symptoms improved with a remaining mild skew deviation anti-ma1/-ma2 antibodies were persistently undetectable PET at last visit was normal csf at last visit was normal

Treatment & Mechanisms

Proposed Remission Mechanisms

The probable anti-cancer effect of the anti-ma immune response paraneoplastic antibodies are known to bind to tumor cells the transient anti-ma reactivity might have evolved in the course of a para- or postinfectious immune response

Clinical Treatment

None reported

Non-Clinical Treatment

None reported