Case report: Kinetics of human leukocyte antigen receptor HLA-DR during liver injury induced by potassium para-aminobenzoate as assessed for causality using the updated RUCAM.

Potassium para-aminobenzoate (POTABA) is used to treat Peyronie's disease by decreasing fibrosis and plaque size progression. Among potential side effects, drug-induced liver injury (DILI) attributed to POTABA administration has been reported in a few cases and inferred to immune hypersensitivity. In the present case, we investigated clinical, biochemical, and serological features as well as searched for non-drug-related causes, and applied the updated Roussel Uclaf Causality Assessment Method (RUCAM) confirming a highly probable causality of POTABA-induced liver injury. Moreover, we here observed specific activated CD3+ T lymphocytes during the acute phase of liver injury by monitoring of human leukocyte antigen receptor (HLA-DR) expression. Furthermore, improvement of biochemical markers of liver injury after POTABA withdrawal was associated with a rapid decline of CD3+ HLA-DR+ immune cells. In contrast, CD14+ monocytes expressing HLA-DR remained stable during recovery from liver injury. These observations implicate a specific involvement of activated T lymphocytes in liver injury mediated by POTABA. Clinicians should be aware of POTABA-induced liver injury, and measurement of activated immune cells by assessment of HLA-DR could provide pathomechanistic insights enabling biomonitoring of recovery from DILI.

NFATc1 signaling drives chronic ER stress responses to promote NAFLD progression.

OBJECTIVES: Non-alcoholic fatty liver disease (NAFLD) can persist in the stage of simple hepatic steatosis or progress to steatohepatitis (NASH) with an increased risk for cirrhosis and cancer. We examined the mechanisms controlling the progression to severe NASH in order to develop future treatment strategies for this disease. DESIGN: NFATc1 activation and regulation was examined in livers from patients with NAFLD, cultured and primary hepatocytes and in transgenic mice with differential hepatocyte-specific expression of the transcription factor (Alb-cre, NFATc1c.a . and NFATc1Δ/Δ ). Animals were fed with high-fat western diet (WD) alone or in combination with tauroursodeoxycholic acid (TUDCA), a candidate drug for NAFLD treatment. NFATc1-dependent ER stress-responses, NLRP3 inflammasome activation and disease progression were assessed both in vitro and in vivo. RESULTS: NFATc1 expression was weak in healthy livers but strongly induced in advanced NAFLD stages, where it correlates with liver enzyme values as well as hepatic inflammation and fibrosis. Moreover, high-fat WD increased NFATc1 expression, nuclear localisation and activation to promote NAFLD progression, whereas hepatocyte-specific depletion of the transcription factor can prevent mice from disease acceleration. Mechanistically, NFATc1 drives liver cell damage and inflammation through ER stress sensing and activation of the PERK-CHOP unfolded protein response (UPR). Finally, NFATc1-induced disease progression towards NASH can be blocked by TUDCA administration. CONCLUSION: NFATc1 stimulates NAFLD progression through chronic ER stress sensing and subsequent activation of terminal UPR signalling in hepatocytes. Interfering with ER stress-responses, for example, by TUDCA, protects fatty livers from progression towards manifest NASH.

Cytomegalovirus colitis in inflammatory bowel disease and after haematopoietic stem cell transplantation: diagnostic accuracy, predictors, risk factors and disease outcome.

BACKGROUND: Concurrent cytomegalovirus (CMV) colitis in inflammatory bowel disease (IBD) and after haematopoietic stem cell transplantation (HSCT) is an important clinical entity associated with high rates of morbidity and mortality. METHODS: A retrospective study of 47 patients with IBD and 61 HSCT patients was performed regarding the evaluation of diagnostic accuracy of applied methods, predictors, risk factors for CMV disease manifestation, the proportion of patients with antiviral treatment and disease outcome. RESULTS: The sensitivity of quantitative PCR (qPCR) with a cut-off value of >250 copies/mg for CMV colitis in patients with IBD and HSCT patients was 79% and 92%, respectively. Predictors for CMV colitis in the IBD cohort were anaemia and the presence of endoscopic ulcers. Glucocorticoids, calcineurin inhibitors and >2 concurrent lines of treatment with immunosuppressive drugs could be identified as risk factors for CMV colitis in the IBD cohort with an OR of 7.1 (95% CI 1.7 to 29.9), 21.3 (95% CI 2.4 to 188.7) and 13.4 (95% CI 3.2 to 56.1), respectively. Predictors and risk factors for CMV gastroenteritis in the HSCT cohort was the presence of endoscopic ulcers (OR 18.6, 95% CI 3.3 to 103.7) and >2 concurrent lines of treatment with immunosuppressive drugs. Antiviral therapy was administered in 70% of patients with IBD and 77% of HSCT patients with CMV disease. 71% of antiviral-treated patients with IBD showed an improvement of their disease activity and 14% underwent colectomy. The mortality rate of HSCT patients was 21% irrespective of their CMV status. CONCLUSIONS: In addition to the implementation of histological methods, qPCR may be performed in patients with suspected high-risk IBD and HSCT patients for CMV colitis. Independent validations of these results in further prospective studies are needed.