Title:
Posterior Reversible Encephalopathy Syndrome (PRES) in the Postpartum After Postdural Puncture Headache.
Background:
Posterior Reversible Encephalopathy Syndrome (PRES) is rare and characterized by insidious onset of headache, altered mental status, seizures and cortical blindness with posterior leukoencephalopathy on imaging studies.1 Incidence and pathophysiological mechanism are unknown. It has been associated with hypertensive encephalopathy, immunosuppression and postpartum eclampsia2. 
We describe a case of PRES associated with postdural puncture headache (PDPH).

Case Report:
25YO female, ASA1. PDPH following epidural analgesia for labour. Headache improved after 4 days of conservative treatment. Hospital discharge. 2 days after, readmission: generalized tonic-clonic seizure, bilateral amaurosis and headache (no longer postural). Acute Pain Unit activated. Cerebral computed tomography scan(CT): bilateral occipital hypodensities; Venous-CT excluded thrombosis. Brain magnetic resonance(MR) imaging: hyperintense areas on T2/FLAIR within the bilateral parietooccipital lobes with vasogenic edema; patchy left parietal area with cytotoxic oedema. MR angiography: arterial vasospasm, especially at posterior circulation, and subdural effusions. 
Treatment: Dorsal decubitus at 0º, hydration, paracetamol, nonsteroidal anti-inflammatory drug, caffeine and nimodipine. She remained hemodynamically stable; clinical and imaging improvement. After complete recovering from blindness she was discharged. She remained asymptomatic at six month and one year evaluation.
Discussion:
In this case clinical symptoms and neuroimaging findings are compatible with PRES.
The exact PRES mechanism remains unknown. The temporal association of encephalopathy with diffuse cerebral vasospasm after an episode of PDPH may be causative.
Prompt recognition and treatment are crucial to avoid the permanent damage leading to sequelae and mortality.
References:
1-	T Hammad et al. Posterior Reversible Encephalopathy Syndrome Secondary to CSF Leak and Intracranial Hypotension: A Case Report and Literature Review. Case Reports in Neurological Medicine 2015; 
2-	H Chiu-Ming, C Kwok-Hon.Posterior Reversible Encephalopathy Syndrome with Vasospasm in a Postpartum Woman After Postdural Puncture Headache Following Spinal Anesthesia. AnesthAnalg 2007; 105:770-2.

Learning points: PRES is a possible complication of postdural puncture. It must be early diagnosed and properly treated.

Posterior Reversible Encephalopathy Syndrome (PRES) in the postpartum after postdural puncture headache