An Acute Infection due to Hepatitis E in the Context of a Patient with Rituximab and Methotrexate Therapy.

Background: This report presents the influence of immunosuppression by new rheumatological therapies on hepatitis E virus infection in a 54-year-old male patient with an anti-synthetase syndrome and treatment with methotrexate and rituximab. Case description: The patient arrived at the Emergency Department with epigastric pain, vomiting and dark urine. Initial examination revealed signs of inflammation and hepatic dysfunction. Subsequent laboratory tests and imaging confirmed acute hepatitis E infection in the context of recent initiation of rituximab therapy. Despite initial suspicion of pancreatitis, subsequent investigations ruled out pancreatic involvement. Treatment with ribavirin, along with supportive measures, led to significant clinical improvement with resolution of jaundice, ascites, and oedema. Conclusions: This case underscores the importance of considering hepatitis E in patients with autoimmune conditions, especially when initiating immunosuppressive therapies, a situation that is not well described in scientific literature and is increasingly common, necessitating proper recognition. LEARNING POINTS: Suspect hepatitis E virus infection in the presence of persistent liver failure of unknown cause.Recognise immunosuppression as a cause of increased risk of hepatitis E infection.Take into account the repercussions of immunosuppressive therapy such as rituximab regarding hepatitis E infections in immunocompromised patients.

The Role of GAB1 in Cancer.

GRB2-associated binder 1 (GAB1) is the inaugural member of the GAB/DOS family of pleckstrin homology (PH) domain-containing proteins. Upon receiving various stimuli, GAB1 transitions from the cytoplasm to the membrane where it is phosphorylated by a range of kinases. This event recruits SH2 domain-containing proteins like SHP2, PI3K's p85 subunit, CRK, and others, thereby activating distinct signaling pathways, including MAPK, PI3K/AKT, and JNK. GAB1-deficient embryos succumb in utero, presenting with developmental abnormalities in the heart, placenta, liver, skin, limb, and diaphragm myocytes. Oncogenic mutations have been identified in the context of cancer. GAB1 expression levels are disrupted in various tumors, and elevated levels in patients often portend a worse prognosis in multiple cancer types. This review focuses on GAB1's influence on cellular transformation particularly in proliferation, evasion of apoptosis, metastasis, and angiogenesis-each of these processes being a cancer hallmark. GAB1 also modulates the resistance/sensitivity to antitumor therapies, making it a promising target for future anticancer strategies.