Non-cirrhotic Hyperammonemia - Differential Diagnosis Framework



Hematologic & Vascular:

 • Multiple myeloma & Acute leukemia (plasma cells —Y t amino acid metabolism)

 • Congenital portosystemic shunt (Abernethy Malformation)



Infections:

 • Urease-producing bacteria: Proteus mirabilis, Escherichia coli, Klebsiella

 • Results in severe hyper-NH3 if elderly + urinary retention



Unmasked Urea Cycle Defects

 • OTC deficiency (XLR)

 • Deficiency unmasked by:

    - Seizure, Starvation (↑ muscle catabolism)

    - TPN, GI bleeding (↑ nitrogen loading)

    - Infections (direct ↑)



Drugs:

 • Valproic acid 

 • Carbamazepine

 • Salicylates

 • Sulfadiazine



By Andrew Sanchez M.D. @ASanchez_PS



#Hyperammonemia #ammonia #Differential #Diagnosis #Pathophysiology