COMBINED CENTRAL AND PERIPHERAL DEMYELINATION SYNDROME/DEMYELINATING POLYNEUROPATHY; This spontaneous report was received from literature. This report concerned a 59 year old female of an unspecified race and ethnicity. The objective of this case report was to report a case of combined central and peripheral combined demyelination (CCPD) syndrome after COVID19 vaccine with brick improvement to steroids and PLEX (unspecified) and provide a brief literature review of CCPD etiology and management. The patient's weight, height, and medical history were not reported. The patient had previously received covid-19 vaccine ad26.cov2.s (Unspecified manufacturer) (Dose number in series: 1) (suspension for injection, route of admin, and batch number were not reported, expiry: Unknown) dose was not reported, 1 total, dose 1 (first dose) administered on an unspecified date for covid-19 prophylaxis. It was unknown whether patient had any adverse events following vaccination with first dose of covid-19 vaccine ad26.cov2.s (Unspecified manufacturer) (Dose number in series: 1). The patient received covid-19 vaccine ad26.cov2.s (Dose number in series: 2) (suspension for injection, route of admin, and batch number were not reported, expiry: Unknown) dose was not reported, 1 total, dose 2 (second dose) administered on an unspecified date for covid-19 prophylaxis. The batch number was not reported. Per procedure, no follow-up will be requested for this case. No concomitant medications were reported. On an unspecified date (four weeks after receiving second dose of covid-19 vaccine ad26.cov2.s), the patient experienced progressive lower extremity pain, weakness and urinary incontinence (Dose number in series: 2). On examination the patient was notable for mild somnolence, restricted lateral gaze, right eye red desaturation without APD (Afferent Pupillary Defect), ocular ataxia, left lower facial weakness, and lower extremity paresis with decreased reflexes (Dose number in series: 2). Laboratory data (dates unspecified) included: MRI (Magnetic resonance imaging) of the brain and spinal cord showed multifocal supratentorial, intratentorial, cervical and thoracic cord white matter signal abnormalities with trace enhancement in combination with marked cauda equina enhancement and CSF test showed albuminocytologic dissociation (protein of 184 and 2 nucleated cells). The patient was tested negative for NMO (Neuromyelitis optica spectrum), Anti-MOG (Anti-myelin oligodendrocyte glycoprotein) and neurofascin-155 antibodies. The patient underwent for Electromyelogram and nerve conduction studies, and showed consistent with a demyelinating polyneuropathy (combined central and peripheral demyelination syndrome) (Dose number in series: 2). The patient was treated with a 1 gram IV (Intravenous) methylprednisolone daily and five treatments of plasma exchange. It was reported that at six months, the patient had nearly returned to her previous baseline. The action taken with covid-19 vaccine ad26.cov2.s was not applicable. The patient was recovering from combined central and peripheral demyelination syndrome/demyelinating polyneuropathy. The authors emphasized that CCPD (central and peripheral demyelination syndrome) is a rare inflammatory neurologic condition of peripheral and central demyelination. The etiology remains unclear, though viral infections and immunizations have been reported to proceed CCPD in some patients and limited data was available to guide treatment but PLEX (Unspecified), IVIG (Intravenous Immunoglobulin) and steroids are the most common. Outcomes are heterogeneous and methods to predict long term course remains uncertain. Also stated that to their knowledge, this is the first reported case of CCPD after the COVID 19 vaccine. This report was serious (Other Medically Important Condition).; Sender's Comments: V0: 20221240107-combined central and peripheral demyelination syndrome/demyelinating polyneuropathy- The event has an compatible/suggestive temporal relationship, is unlabeled, and has unknown scientific plausibility. There is no information on any other factors potentially associated with the event. Therefore, the WHO Causality is considered indeterminate. The company causality is considered unassessable.