Sara Redenšek

By Sara Redenšek and Vita Dolžan

Psoriasis is a chronic systemic, immune-mediated disorder of unknown aetiology, usually presenting with typical inflammatory skin lesions and/or joint manifestations, but systemic inflammation that may lead to the development of co-morbidities may also be present. First-line therapy encompasses local cutaneous treatment and phototherapy, but with more severe symptoms or systemic course, systemic treatment with methotrexate (MTX), immunosuppressant cyclosporine, retinoid acitretin or biologicals may be used. Treatment response varies between patients in terms of efficacy and/or toxicity, which could, among other reasons, be due to genetic differences between patients. Approximately 10–30% of patients experience adverse drug reactions with MTX treatment, leading to discontinuation of MTX mostly due to hepatotoxicity. Around 15% of patients experience adverse events when treated with biologicals; however, the most frequent reason for discontinuation is inefficacy or loss of the initially favourable response over time. Inefficacy or occurrence of adverse drug reactions cannot be predicted, so genetic biomarkers of drug response in combination with clinical data could be helpful in treatment planning. Several polymorphic genes have already been associated with treatment outcome, most of them involved in drug metabolism, transport and target pathways. Genetic biomarkers could be helpful in personalized care of psoriasis patients in order to prevent adverse events or predict inefficacy of a certain drug.

Part of the book: Psoriasis

By Sara Redenšek, Maja Trošt and Vita Dolžan

Parkinson’s disease (PD) is a chronic progressive neurodegenerative brain disorder presenting with motor signs and symptoms, such as akinesia, rest tremor, rigidity, and later in disease progression postural instability. However, nonmotor symptoms may harm patients’ quality of life even more than the motor ones. The etiopathogenesis is not clear yet. PD may develop due to a combination of genetic and environmental factors. It is treated symptomatically with dopaminergic drugs. The gold standard of PD management is L-Dopa, however also other drugs are frequently used, such as dopamine agonists, MAOB inhibitors, COMT inhibitors, and occasionally amantadine and anticholinergic drugs. Many patients experience several adverse events of L-Dopa treatment, such as different motor complications. Furthermore, nonmotor adverse events of dopaminergic treatment may occur. The efficacy of drugs varies between patients as well. Several polymorphic genes have already been associated with treatment outcome in PD, such as metabolic enzymes, transport and receptor genes, and might serve as treatment outcome prediction factors. As gene-environment interactions were also shown to contribute to PD development, they might also be able to predict treatment response. Such genetic biomarkers could be helpful in personalized care of PD patients to prevent adverse events and inefficacy of a certain drug.

Part of the book: Parkinson's Disease