Hyperammonemia Syndrome After Lung Transplantation: A Single Center Experience.
BACKGROUND
Hyperammonemia is a rare, often fatal complication after transplantation. The etiology is unknown, but recognition and rapid treatment may help to improve the survival of this unusual syndrome. We present the largest case series to date of hyperammonemia after lung transplantation (LTx) and discuss a treatment protocol that has been developed at our institution.


METHODS
We conducted a retrospective cohort series of patients who underwent LTx between January 1, 2000, and December 31, 2013. Patients who developed hyperammonemia syndrome in the posttransplantation period, which was defined as symptoms of encephalopathy and plasma ammonia level exceeding 200 μmol/L on at least 1 occasion, were included. Data including demographics, antimicrobial and immunosuppression regimens, ammonia levels and other pertinent laboratory data, treatments administered, and outcomes were recorded.


RESULTS
Eight of 807 lung transplant recipients developed hyperammonemia syndrome postoperatively during this time period. Median time to onset was 9.0 days, and median peak ammonia level was 370 μmol/L. All 8 patients were treated with hemodialysis, 7 of 8 patients were treated with bowel decontamination, and 5 of 8 patients were treated with nitrogen scavenging agents. Six of the 8 patients died.


CONCLUSIONS
The incidence of hyperammonemia syndrome in LTx patients was approximately 1%. Future research is needed to determine the efficacy of treatment, including hemodialysis, bowel decontamination, antibiotics, and the use of nitrogen scavenging agents in lung recipients with hyperammonemia.
1 Division of Pulmonary and Critical Care Medicine, Washington University School of Medicine, St. Louis, MO. 2 Department of Pharmacy, Barnes-Jewish Hospital, St. Louis, MO. 3 Division of Cardiothoracic Surgery, Washington University in St. Louis, St. Louis, MO.
Catherine
C
Chen
Karen B
KB
Bain
Jennifer A
JA
Iuppa
Roger D
RD
Yusen
Derek E
DE
Byers
George A
GA
Patterson
Elbert P
EP
Trulock
Ramsey R
RR
Hachem
Chad A
CA
Witt
D000368:Aged; D000641:Ammonia / Q000097:blood*; D001120:Arginine / Q000627:therapeutic use; D015415:Biomarkers / Q000097:blood; D002331:Carnitine / Q000627:therapeutic use; D003131:Combined Modality Therapy; D003666:Decontamination / Q000379:methods*; D005260:Female; D006801:Humans; D022124:Hyperammonemia / Q000097:blood / Q000175:diagnosis / Q000209:etiology / Q000401:mortality / Q000628:therapy*; D007166:Immunosuppressive Agents / Q000627:therapeutic use; D016040:Lung Transplantation / Q000009:adverse effects* / Q000401:mortality; D008297:Male; D008875:Middle Aged; D008923:Missouri; D010648:Phenylacetates / Q000627:therapeutic use; D020011:Protective Agents / Q000627:therapeutic use*; D006435:Renal Dialysis; D012189:Retrospective Studies; D020160:Sodium Benzoate / Q000627:therapeutic use; D013577:Syndrome; D013997:Time Factors; D016896:Treatment Outcome; D015854:Up-Regulation
D015415:Biomarkers; D007166:Immunosuppressive Agents; D010648:Phenylacetates; D020011:Protective Agents; D000641:Ammonia; D001120:Arginine; C025136:phenylacetic acid; D020160:Sodium Benzoate; D002331:Carnitine