AST is a marker of hepatocellular injury, predominantly alcohol-related liver injury (chronic hepatitis C) and cirrhosis (chronic hepatitis B). In alcoholic liver disease, P-5-P becomes deficient, which is greater on ALT activity compared to AST activity. Consequently, ALT activity is reduced, whereas AST activity is increased ². The hallmark finding for alcohol liver disease is the AST to ALT ratio of at least 2:1 ³. The marked laboratory findings for ischaemic hepatitis is an elevated bilirubin level, however, AST levels are > 10 times the upper reference range limit ². Acute viral hepatitis, drug or toxin induced liver disease and ischaemic liver injury are characterised by extremely elevated aminotransferase levels ³.

Muscular dystrophy, including Duchenne muscular dystrophy is characterised by hypertransaminasemia. Elevations in both ALT and AST are most striking in the early stages of muscular disease, prior to the onset or only when subtle symptoms are present. Consequently, during these initial stages, ALT/AST testing can enable the early identification of disease and so the early intervention of treatment plans ⁴.

A correlation between serum albumin concentrations and ill-health has been identified, with an astonishingly strong inverse correlation between serum albumin and mortality risk ². The association of it with other confounding variables increase mortality (fig 1). The concentration is related to the rates of synthesis and catabolism, but also influenced by state of hydration, lymphatic return, external losses (burns), and rates of transcapillary escape. In starvation, both the synthesis and catabolism fall, whereas in nephrotic syndrome, synthesis rises and catabolism falls ³.

Fig. 1. Potential associations between serum albumin and mortality ³

A direct, casual relationship between serum albumin and mortality is represented by arrow a or the sequence b, a. A non-casual, confounding relationship is represented by arrows b and c. A co-causal relationship is represented by arrows a and c.

Low circulating albumin is associated with an adverse metabolic profile characterised by increased adipose tissue inflammation, glucose concentrations, and adiposity. It inversely correlates with type 2 diabetes mellitus (T2DM) risk ⁴. Moreover, serum albumin concentrations are inversely correlated with the risk of ketosis in hospitalised patients with T2DM and may require the early initiation of insulin therapy to prevent complications. It is a promising prognostic marker in hospitalised diabetic patients with acute hyperglycaemia ⁵.

Low levels of serum albumin is common in cirrhosis and is associated with a reduced survival rate. In this setting, the native isoform can be severely reduced as a result of several post-transcriptional changes that impair the non-oncotic properties of the molecule ⁶.