Hepatic encephalopathy
Hepatic encephalopathy (HE, Synonyms: portosystemic encephalopathy, Hepatoportal encephalopathy, minimal encephalopathy, Hepatoenzephalopathie ) is a potentially reversible brain disorder that results from an inadequate detoxification function of the liver.
Pathophysiology
This impaired detoxification function is a consequence of acute liver failure or chronic liver disease (eg cirrhosis of the liver with the formation of portocaval collateral circulation ), but also a therapeutically applied shunts, resulting in an increase in the concentration of various substances in the body. Mention may be made here:
- Ammonia, a decomposition product of amino acid metabolism which normally detoxifies via the urea cycle in the liver cells
- Mercaptans ( partly responsible for the fetor hepaticus )
- Gamma -aminobutyric acid ( GABA)
- Short-chain fatty acids
- Aromatic amino acids ( while the concentration of branched chain amino acids decreases)
The most severe form of hepatic encephalopathy (stage IV) is also referred to as hepatic coma, hepatic coma or hepatic coma decay.
Symptoms
After initially running with no obvious symptoms proliferation of glial cells in the brain ( gliosis ), there is initially mostly mild psycho- syndromes, which are often detected only for friends and relatives of the patient. This can result in a poverty of movement and facial expression, tremors, fluttering of the eyelids and other muscle twitching ( myoclonus ). In advanced stages, a compulsive need for sleep, muscle breakdown, grobschlägiges trembling of the hands ( " flapping tremor" ), unsteadiness of gait, and finally an increasing confusion, somnolence, sweet breath ( fetor hepaticus ), jaundice ( jaundice) and fluid retention in the abdomen you may also have ( ascites).
Staging
- Deferred or minimal hepatic encephalopathy ( MHE ): lack of concentration, disturbance in attention, memory difficulties, decreasing responsiveness, loss of volition. At most slight disturbances of fine motor skills.
- Stage I: Visible reduction in the level of consciousness with an increasing need for sleep, clearer drive failure and loss of intellectual capacity. Abnormal disturbances of fine motor skills with a change of typeface, " flapping tremor" and slowed movement.
- Stage II: Significant reduction in the level of consciousness with disorientation, pronounced memory impairment, impoverishment of emotional life and delayed response to verbal stimuli. Slurred speech (dysarthria ), " flapping tremor" and increased muscle tension. (Somnolence: severe drowsiness )
- Stage III: Severe disturbance of consciousness ( stupor: mostly sleeping, but erweckbarer patient), loss of orientation, disorientation, incoherent speech, decreased response to painful stimuli. Increased muscle tension through to muscle stiffness (spasticity ), bowel and bladder incontinence, gait and unsteadiness (ataxia).
- Stage IV: Unconsciousness with no reaction to painful stimuli ( coma). Extinction of the tendon reflexes, muscle stiffness with flexion and extension attitude, in the advanced stage loss of muscle tone.
Therapy
- Treatment of the underlying disease.
- Lactulose is a synthetic sugar ( disaccharide ) of galactose and fructose and influences the intestinal microflora in the sense of being overweight lactic acid forming intestinal bacteria, thereby forming ammonia intestinal bacteria are suppressed as well as the urease, which catalyzes a formation of ammonia is inhibited. Further, in the now lower pH protonated ammonia to ammonium, which is precipitated as a salt.
- Neomycin is a local antibiotic that is effective when administered orally in the gut to kill the ammonia- forming bacteria.
- Likewise, rifaximin, a non- absorbable and, therefore, local acting antibiotic, can be used to kill the bacteria. In an observation period of six months the occurrence of episodes of encephalopathy was reduced by about half.
- For certain patients plasmapheresis or an albumin dialysis using the MARS ® come (Molecular Adsorbents Recirculating System) in question.