Chronic kidney disease (CKD) arises from many heterogeneous disease pathways that alter the function and structure of the kidney irreversibly, over months or years. The diagnosis of CKD rests on establishing a chronic reduction in kidney function and structural kidney damage. The best available indicator of overall kidney function is glomerular filtration rate (GFR), which equals the total amount of fluid filtered through all of the functioning nephrons per unit of time
The definition and classification of CKD have evolved over time, but current international guidelines define CKD as decreased kidney function shown by GFR of less than 60 mL/min per 1·73 m2, or markers of kidney damage, or both, of at least 3 months duration, regardless of underlying cause . When GFR is less than 15 mL/min per 1·73m2 , a person has reached end stage kidney disease (ESKD), at which point kidney function is no longer able to sustain life over the long term. Options for patients with ESKD are kidney replacement therapy (in the form of dialysis or kidney transplantation), or conservative care (also called palliation or non-dialytic care
Encephalopathy detected in patients with chronic kidney disease results from their exposure to several factors, such as uremia, hypertension, and fluid, and electrolyte disturbances (Brouns R, DyDeyn pp,2004)
Uremic encephalopathy features include alterations of mental status (alertness and awareness alterations, poor concentration, psychosis, and hallucinations, without treatment of which stupor, and coma may develop) and motor system abnormalities, such as clouding of the sensorium as an early feature and delirium, seizures, and coma as late features (Palmer sc ,etal,2010)EEG is useful in assessing patients in uremic encephalopathy and in monitoring their progress. Electroencephalographic (EEG) findings correlate with clinical symptoms and, therefore, may be of diagnostic value. In addition, it can be useful to exclude other causes of confusion such as infection or structural abnormalities (Dijck Annemie Van,etal,2012).
The EEG in uremic encephalopathy is generally abnormal, showing generalized slowing that becomes more severe as the condition worsens. EEG in CKD usually shows irregular low voltage with slowing of the posterior dominant alpha rhythm and occasional theta bursts. Prolonged bursts of bilateral, synchronous slow and sharp waves or spike and waves are characteristic. These changes stabilize with dialysis. EEG abnormalities in uremic encephalopathy is reflected through appearance of theta waves, disappearance of normal basic rhythms and diminished reactivity of EEG to afferent stimulation and domination by generalized delta activity. All these changes are mostly appreciated in the frontal leads (Al Arieff,Philadelphia,Ssaunders,2004)(Cl fraser, Arieff,Philadelphia,2001)
A lot of studies have been done about uremic encephalopathy in acute renal failure patients. Very few data are available regarding EEG changes in CKD. This study evaluates the EEG findings in different stages of CKD.
