Valproate is widely used because of broad spectrum of action, but it can produce an encephalopathy resulting from hyperammonemia even at the therapeutic range of valproate and is called as valproate-induced encephalopathy (VHE). Delay in recognition of VHE can result in the development of potentially life-threatening complications. Fortunately, it is reversible with discontinuing valproate. A 65-year-old man became progressively lethargic with impaired gait and poor cognitive function while taking valproate as alternative to zonisamide. Routine investigations of admission profiles were performed but revealed no abnormalities. Next, we checked serum ammonia level to identify other possible causes and detected hyperammonemia despite the therapeutic range of valproate in the absence of any abnormalities in liver enzymes. On cessation of valproate, he has achieved dramatic clinical improvement including the reversal of hyperammonemia. We confirmed the diagnosis of VHE. This emphasizes the importance of rapid diagnosis and proper management of VHE in order to prevent the neurological damage and minimize complications.
Aged ; Ammonia ; Gait ; Humans ; Hyperammonemia ; Isoxazoles ; Liver ; Valproic Acid

Seventeen dogs were treated with L-ornithin-L-aspartate (LOLA; experimental group). Three dogs were treated with lactulose recognized therapy (control group). Following LOLA administration, 15 dogs experienced a significant decrease in ammonia level (p < 0.05) and showed clinical signs of improvement. However, there were no clinical signs of improvement in two dogs, even though the ammonia level decreased. Conversely, the clinical signs of the control group also improved and the ammonia level decreased, although these changes were not significant (p > 0.05). These results suggest that LOLA is an effective drug to treat hyperammonemia in veterinary medicine.
Ammonia ; Animals ; Dogs* ; Dipeptides* ; Hepatic Encephalopathy* ; Hyperammonemia ; Lactulose ; Veterinary Medicine

Neonatal hyperammonemia is a disorder of ammonia metabolism that occurs in the neonatal period. It is a clinical syndrome characterized by abnormal accumulation of ammonia in the blood and dysfunction of the central nervous system. Due to its low incidence and lack of specificity in clinical manifestations, it is easy to cause misdiagnosis and missed diagnosis. In order to further standardize the diagnosis and treatment of neonatal hyperammonemia, the Youth Commission, Subspecialty Group of Neonatology, Society of Pediatrics, Chinese Medical Association formulated the expert consensus based on clinical evidence in China and overseas and combined with clinical practice experience,and put forward 18 recommendations for the diagnosis and treatment of neonatal hyperaminemia.
Humans ; Infant, Newborn ; Ammonia ; China ; Consensus ; Hyperammonemia/therapy*

Cardiomyopathies ; diagnosis ; Carnitine ; deficiency ; Humans ; Hyperammonemia ; diagnosis ; Infant, Newborn ; Male ; Muscular Diseases ; diagnosis

BACKGROUND: Differential diagnosis between a generalized tonic-clonic seizure and syncope may be difficult due to similar clinical features. The need for a biological marker to distinguish a seizure from syncope has been emphasized from past studies. Transient hyperammonemia could be an indicator of recent convulsive seizure. The purpose of this study is to review the use of plasma ammonia level in the differential diagnosis of seizure and syncope. METHODS: Adult patients who were admitted to the Department of Neurology at Gangnam Severance Hospital with final diagnosis of a generalized tonic-clonic seizure or syncope were eligible for this study. Plasma ammonia levels were checked within 8 hr after an insult. RESULTS: Among the patients with a loss of consciousness who underwent analysis of plasma ammonia level, diagnoses were made with a seizure (n=65) and syncope (n=38). The seizure group had 70.29+/-70.86 micromol/L and the syncope group had 28.37+/-10.27 micromol/L of ammonia level, respectively. The seizure group presented with a significantly increased plasma ammonia (p<0.05) compared to the syncope group. The cut-off value with the reliable diagnostic level was defined as 36 micromol/L (=61.308 microg/dL) with a sensitivity of 0.65 and specificity of 0.80 by receiver operating characteristic (ROC) curve analysis. CONCLUSIONS: Plasma ammonia measurement during acute post-ictal period may be a useful test for the identification and the differential diagnosis of seizures and syncope.
Adult ; Ammonia ; Biomarkers ; Diagnosis, Differential ; Humans ; Hyperammonemia ; Neurology ; Plasma ; ROC Curve ; Seizures ; Sensitivity and Specificity ; Syncope ; Unconsciousness

5-Fluorouracil (5-FU) is a chemotherapeutic agent commonly used in the treatment of a variety of solid tumors. Common adverse effects of fluorouracil chemotherapy include diarrhea, mucositis and myelosuppression. However, neurologic toxicities including hyperammonemic encephalopathy are rare and not well recognized. Transient hyperammonemic encephalopathy related to continuous infusion of high-dose 5-FU has rarely been reported. We report four cases of transient hyperammonemic encephalopathy in patients receiving continuous infusion of 5-FU. The mentality of all patients was altered during or just after the infusion of 5-FU. There were no focal neurological signs, laboratory excluding hyperammonemia or radiological abnormalities. After patients received adequate hydration and repeated lactulose enema, the mental status completely recovered within one or two days, and serum ammonium level subsequently returned to normal. In conclusion, we suggest that a transient hyperammonemic encephalopathy should be considered in differential diagnosis of patients receiving continuous 5-FU infusion with altered mentality.
Ammonium Compounds ; Diagnosis, Differential ; Diarrhea ; Drug Therapy ; Enema ; Fluorouracil* ; Humans ; Hyperammonemia ; Lactulose ; Mucositis

Transient hyperammonemia in a newborn is an overwhelming disease manifested by hyperammonemic coma. The majority of affected newborns are premature and have mild respiratory syndrome. The diagnosis may be difficult to determine. This metabolic disorder is primarily characterized by severe hyperammonemia in the postnatal period, coma, absence of abnormal organic aciduria and normal activity of the enzymes of the urea cycle. Hyperammonemic coma may develop within 2-3 days of life, although its etiology is unknown. Laboratory studies reveal marked hyperammonemia (>4,000 micromol/L). The degree of neurologic impairment and developmental delay in this disorder depends on the duration of hyperammonemic coma. Moreover, the infant may succumb to the disease if treatment is not started immediately and continued vigorously. Hyperammonemic coma as a medical emergency requires dialysis therapy. Here, we report a case of severe transient hyperammonemia in a preterm infant (35 week of gestation) presented with respiratory distress, seizure, and deep coma within 48 hours and required ventilatory assistance and marked elevated plasma ammonia levels. He survived with aggressive therapy including peritoneal dialysis, and was followed 2 years later without sequelae.
Ammonia ; Coma ; Dialysis ; Emergencies ; Humans ; Hyperammonemia ; Infant ; Infant, Newborn ; Infant, Premature ; Peritoneal Dialysis ; Plasma ; Seizures ; Urea

A deficiency of the urea cycle enzyme, argininosuccinate synthetase which is produced in liver, makes citrullinemia, which is an autosomal recessive disorder. As the liver is the only organ which transforms ammonia into urea, liver transplantation has been considered as an effective alternative therapy to classical dietary and medical therapy. We have experienced perioperative anesthetic care for a 27-year-old male with citrullinemia undergoing successful living donor auxiliary partial orthotopic liver transplantation (APOLT). After the liver transplantation, the postoperative clinical courses of the patient were uneventful, and the neurological symptoms were completely resolved. The plasma concentrations of ammonia and citrulline normalized rapidly without any kinds of protein dietary restrictions. We present this case with a brief review of literature.
Adult ; Ammonia ; Argininosuccinate Synthase ; Citrulline ; Citrullinemia ; Humans ; Hyperammonemia ; Liver ; Liver Transplantation ; Living Donors ; Male ; Plasma ; Urea

The clinical syndrome of hyperammonemic encephalopathy is often encountered in the context of decompensated liver disease. Although it is rare in patients without hepatic disease, non-hepatic causes cannot be excluded. Anesthesiologists should be careful in choosing the anesthetic agent and perioperative management for hyperammonemic patients in order to avoid acute hyperammonemia and encephalopathy. We report successful general anesthesia during GDC (Guglielmi detachable coil) embolization for a large unruptured aneurysm in the right distal internal carotid artery in a female patient with hyperammonemic encephalopathy that was caused by a portal-systemic shunt.
Anesthesia ; Anesthesia, General ; Aneurysm ; Carotid Artery, Internal ; Female ; Hepatic Encephalopathy* ; Humans ; Hyperammonemia ; Intracranial Aneurysm* ; Liver Diseases

Hyperammonemia in the newborn often leads to severe fatal illness associated with hyperammonemic encephalopathy. Transient hyperammonemia in newborns (THAN) is characterized by self-limiting, transient hyperammonemia during the neonatal period. THAN may have favorable long-term outcomes if it is diagnosed early and appropriately managed. However, severe hyperammonemia can develop even in newborns with THAN, which may require emergent management. Here we report a case of THAN with severe hyperammonemia during the neonatal period that was successfully treated with continuous renal replacement therapy and nitrogen-scavenging medications. Our patient went on to develop normally and has not re-experienced a hyperammonemic episode until 9 months of age without the administration of a protein restricted diet or medications.
Diet, Protein-Restricted ; Humans ; Hyperammonemia ; Infant, Newborn ; Renal Replacement Therapy ; Urea Cycle Disorders, Inborn