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HYPERORNITHINEMIA-HYPERAMMONEMIA-HOMOCITRULLINURIA (HHH-SYNDROME)

HYPERORNITHINEMIA-HYPERAMMONEMIA-HOMOCITRULLINURIA (HHH-SYNDROME)
ORNITHINE TRANSLOCASE DEFICIENCY
238970
OMIM = Online Mendelian Inheritance of Men
415
mitochondrial ornithine transporter 1
13q14.11
E72.4
rare (<1:2000000, < 100 patients)
autosomal recessive
mutation in the SLC25A15 gene

Adult presentation of hyperornithinemia-hyperammonemia-homocitrullinuria syndrome has rarely been described [Silfverberg T et al. 2018, Filosto M et al. 2013]
Laboratory findingsAmmonia inc (blood)
Hippuric acid normal/inc (urine)
Homocitrulline inc (urine)
Ornithine inc (plasma)
  Orotic acid normal/inc (urine)
    2-Aminopiperid-2-one inc (urine)
    bleeding time dec (blood)
    Citrulline inc (urine)
    Creatine normal/dec (plasma)
    Glutamine inc (plasma)
    L-Lactic acid normal/inc (blood)
    L-Lactic acid normal/inc (urine)
    L-Lysine inc (urine)
    Lactate/Pyruvate ratio normal/inc (urine)
    Ornithine inc (urine)
    Transaminases (ASAT/ALAT) normal/inc (serum)
    Uracil inc (urine)
    Urea normal/dec (serum)
Symptoms  lens opacities
   altered consciousness, consciousness disturbance
   ataxia
   coma
   developmental delay
   encephalopathy
   feeding, protein aversion or intolerance
   liver failure
   liver involvement or dysfunction
   seizures
   spastic diplegia/quadriplegia/tetraplegia
   spastic paraplegia
   strokelike episodes
   temperature instability
   vomiting
    apnea
    behavior, hyperactive, restless
    Coagulopathy/Coagulation factors
    Encephalopathic crisis, acute
    episodic course (clinical symptoms)
    failure to thrive
    feeding difficulties, poor feeding
    growth retardation, poor growth
    hepatomegaly (large liver)
    hyperammonemia
    hypothermia
    hypotonia
    lactic acidosis
    lethargy, drowsiness, apathy
    mental retardation
    night blindness
    onset, adolescent
    onset, childhood
    onset, infancy
    onset, neonatal
    paraparesis/paraplegia
    paresis
    photophobia or photosensitive defect in light-exposed area
    respiratory distress
    tachypnea, hyperpnea, dyspnea, hyperventilation