Background and Aims

A 71-year-old Caucasian female presented to Emergency Department due to sudden worsening of a slow-onset gait impairment and instability. Clinical evaluation revealed ataxia, reduced reflexes, distal hypoesthesia in lower limbs with hypopallesthesia and hyposthenia of the legs. Neurophysiological study showed signs of sensorimotor polyneuropathy.

Methods

Serum testing for onconeural antibodies on linear immunoblotting (EUROIMMUN), anti-GAD antibody in ELISA assay (EUROIMMUN) and additional in-house immunohistochemistry (IHC) on fixed rat cerebellum tissue were performed.

Results

Strong positivity was found for anti-Hu and anti-CV2 antibodies, moreover anti-GAD was >2000 KUI/L. Expanded antigen-panel line blot confirmed high anti-Hu, weak anti-CV2 and weaker anti-GAD65 reactivity and detected weak anti-Zic4 signal. IHC showed a neuronal nuclear pattern.

Thoracic CT scan, transbronchial biopsy of mediastinal lymphadenopathies and a PET/CT study diagnosed metastatic small cell lung carcinoma; 3 months after first hospital admission she died in hospice care.

Conclusions

While the diagnostic value of onconeural antibodies in PNS is well established, their prognostic correlation on survival is still debated, since they can be associated to particularly aggressive neoplastic diseases.