Patients with CVID will be offered to participate in this observational trial during the routine annual visit in the outpatient clinic at the Center of chronic Immunodeficiency (CCI) of the University Medical Center Freiburg, Germany.

Clinical and laboratory data at the time of presentation will be assessed. Additionally, parameters of abdominal ultrasound, duplex sonography of the liver and spleen, and liver and spleen stiffness at the time of presentation will be evaluated. If applicable, clinical and/or interventional parameters indicating clinically significant portal hypertension (i.e. presence of varices or portal-hypertensive gastropathy in esophago-gastroduodenoscopy, presence of ascites) within 12 months prior and after the index visit will be assessed. During the visit, serum/plasma samples and peripheral blood mononuclear cells (PBMC) are collected and stored in an associated biobank.

Patients with CVID can be included in the study. The study cohort will consist of three subgroups: 1) Patients with CVID and autoimmunity, but no liver involvement. 2) Patients with CVID and liver involvement, defined by elevated liver enzymes, abnormal ultrasound and/or abnormal liver biopsy, but no signs of clinically significant portal hypertension and 3) Patients with CVID and clinically significant non-cirrhotic portal hypertension. Further, patients with CVID and diagnosed non-cirrhotic portal hypertension between 01/01/2004 and the start of the prospective part of this study (01/01/2023) will be included retrospectively in this study.

Patients will be recruited during the routine annual visit in the outpatient clinic at the Center of chronic Immunodeficiency (CCI) of the University Medical Center Freiburg, Germany. During the visit a standard ultrasound protocol, including size and morphology of liver and spleen, duplex-sonography of the liver, and measurement of liver and spleen stiffness via transient elastography will be performed as a part of the routine clinical diagnostic. Results from endoscopy or other interventions (esophago-gastroduodenoscopy, invasive measurement of hepatic venous-portal pressure gradient, or TIPS implantation, if applicable) within 12 months prior and after the index visit will be assessed. All non-invasive and invasive interventions will be conducted solely based on clinical decisions made independently from the study inclusion as the study is designed as an observational study.

Detailed patient characteristics, epidemiologic, clinical, imaging and laboratory parameters will be assessed and included in an electronic database.

Apart from these data, patients will be asked to participate in biobank sampling including serum/plasma and peripheral blood mononuclear cells (PBMC) samples from the peripheral veins.

All patients recruited in this study will be followed-up for at least 12 months.

Outcome parameters include parameters from abdominal ultrasound, duplex-sonography and stiffness of liver and spleen, presence or development of clinically significant portal hypertension and non-invasive fibrosis scores based on laboratory and ultrasound parameters.

Inclusion Criteria:

• Patients with CVID

Exclusion Criteria:

• no written informed consent
• concomitant chronic liver disease (viral hepatitis, alcoholic liver disease, steatitic liver disease, hemochromatosis, primary biliary cholangitis, primary sclerosis cholangitis, M. Wilson, alpha-1-antitrypsin deficiency)

Patients with CVID will be included in the study. Patients will be divided into three subgroups: 1) Patients with CVID and autoimmunity, but no liver involvement (n=75) 2) Patients with CVID and liver involvement, defined by elevated liver enzymes, abnormal ultrasound and/or abnormal liver biopsy, but no signs of clinically significant portal hypertension (n=75) 3) Patients with CVID and clinically significant non-cirrhotic portal hypertension (n=75).

Further patients with CVID and diagnosed non-cirrhotic portal hypertension between 01/01/2004 and the start of the prospective part of this study (01/01/2023) will be included retrospectively in this study (n=25)