HaNDL Syndrome: The Innocent Lymphocytic Pleocytosis.

Introduction: HaNDL syndrome is a transient and rare condition that presents with neurological deficit and headache accompanied by lymphocytosis on cerebrospinal fluid (CSF) analysis. It is usually characterized by spontaneous recovery without neurological sequelae. This is a benign condition, which has not yet been adequately defined and includes many diseases in the differential diagnosis. We indicated 2 different cases that applied with acute neurological findings.

Case Report: Two patients who were admitted to our hospital with transient neurological deficits and headaches were evaluated. There was no significant pathology in cranial imaging and EEG reports. Lymphocytic pleocytosis was observed in CSF. Patients were followed up with attacks but were discharged without deficits. We diagnosed the patients with HaNDL syndrome with clinical features, imaging, and laboratory findings.

Conclusion: HaNDL is an underdiagnosed syndrome and it should be considered especially for young patients with headaches is prominent without a risk factor for ischemia, recurrent episodes with neurological symptoms, CSF pleocytosis, and normal imaging findings.Therefore, we wanted to raise awareness for the existence of this rare disease which is a waste of time by performing unnecessary tests and therapies during the diagnosis period.