Primary immunodeficiencies (PID) are a heterogeneous group of disorders with a variable clinical spectrum of manifestations. The central nervous system may be involved in PIDs with symptoms which may present initially or develop at later stages. Neurological manifestations of primary immunodeficiencies are common with diverse pathologic mechanisms. Neurological deficits may be mild or they may greatly influence the course of the disease with major impacts on the quality of life of the patients. Physical examination may give the clinician valuable clues to the cause of PIDs that underlie the neurological signs. Certain neurological abnormalities may later signify a PID. Therefore physicians should be aware of the neurological features accompanying immunodeficiencies. Neuromascular abnormality presenting with ataxia(ataxia-telangiectasia) , flaccid paralysis after live poliovirus immunization (combined or antibody deficiencies) ,pernicious anaemia (CVID), cognitive impairment, nystagmus and cerebellar, spinal and peripheral neuropathies(Chediac-Higashi syndrome), seizures, ataxia and occulomotor and reflex abnormalities(Griscelli syndrome) are examples of neurologic features seen in different immunodeficiency syndromes. Early recognition and treatment is important to prevent or reduce future irreversible neurological sequelae. The aim of this study is to review the neurological manifestations of different primary immunodeficiency syndromes
