AbstractPatients on anti-tuberculosis (anti-TB) therapy are at risk of developing drug-induced liver injury (DILI). Cytokeratin-18 (K18) is an exploratory DILI biomarker that has been developed predominately in Caucasian populations and not African populations in whom TB is common. Our aim was to determine the K18 concentration in different populations with mycobacterial infection and investigate whether K18 has potential as a biomarker of anti-TB DILI.European patients receiving anti-TB therapy were recruited at the Royal Infirmary of Edinburgh, UK (ALISTER - ClinicalTrials.gov Identifier: NCT03211208). African patients with HIV-TB coinfection, receiving anti-TB and anti-retroviral therapy (ART), were recruited at the Infectious Diseases Institute, Kampala, Uganda (SAEFRIF - NCT03982277). Serial blood samples, demographic and clinical data were collected. K18 was quantified using the M65 ELISA.The study had 235 participants (healthy volunteers (n=28); ALISTER: active TB (n=30), latent TB (n=88), non-tuberculous mycobacterial infection (n=25); SAEFRIF: HIV-TB coinfection (n=64)). There was no difference in K18 across the groups and treatment did not affect K18 in the absence of DILI. Alanine transaminase activity (ALT) and K18 were correlated (r=0.42, 95%CI=0.34-0.49, P<0.0001). Variability was higher for K18 than ALT. There were two DILI cases: baseline ALT was 18 and 28 IU/1, peak ALT 431 and 194 IU/L; baseline K18 58 and 219 U/L, peak K18 1247 and 3490 U/L, respectively.Circulating K18 was comparable in UK and Ugandan patients. K18 correlated with ALT and increased with DILI. Further work should determine the diagnostic and prognostic utility of K18 in this global context-of-use.
MicroRNA‐122 and cytokeratin‐18 have potential as a biomarkers of drug‐induced liver injury in European and African patients on treatment for mycobacterial infection