# Hypoaminoacidemia and Pyroglutamic Aciduria: Potential Biomarkers in Malnutrition‐Related Hyperammonemia

## TL;DR

This paper identifies hypoaminoacidemia and pyroglutamic aciduria as potential biomarkers for malnutrition-related hyperammonemia, aiding in faster diagnosis and treatment.

## Contribution

The study introduces a novel biochemical pattern to identify malnutrition-related hyperammonemia more rapidly.

## Key findings

- Three patients with malnutrition-related hyperammonemia showed hypoaminoacidemia and pyroglutamic aciduria.
- Low levels of tyrosine, tryptophan, methionine, and branched-chain amino acids were observed in all patients.
- Recognizing this pattern can lead to quicker protein supplementation in affected individuals.

## Abstract

Hyperammonemia is a medical emergency, and the cause must be identified quickly in order to treat appropriately. Malnutrition is a known risk factor for hyperammonemia; however, there are limited reliable lab indicators used to identify malnutrition. Early identification of the etiology of hyperammonemia is crucial to optimizing care, specifically reintroduction of appropriate amounts of protein into the diet. Herein, we discuss three patients with complex medical histories and clinical signs of malnutrition who presented with hyperammonemia. In all three patients, both hypoaminoacidemia and pyroglutamic aciduria were observed. Specifically, all patients had low tyrosine, tryptophan, methionine, and branched‐chain amino acids. Recognizing this biochemical pattern could result in more rapid initiation of supplementing protein, a primary tenet of treatment in malnutrition‐related hyperammonemia. We highlight the unique features of malnutrition‐related hyperammonemia, propose mechanisms to explain the pattern, and suggest a framework for managing these cases.

We present three patients who underwent a metabolic work‐up for hyperammonemia, later found to have malnutrition‐related hyperammonemia and a biochemical pattern of hypoaminoacidemia and pyroglutamic aciduria suggesting that this pattern could be used to indicate the diagnosis earlier and therefore allow for more rapid initiation of protein supplementation.