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PSC-Related Medical Terms & Reference Links

Below is a list of common PSC-related medical terms, abbreviations, and medical websites.


-omics - In biology, the word -omics refers to the sum of constituents within a cell. The   -omics sciences share the overarching aim of identifying, describing the molecules and molecular processes that contribute to the form and function of cells and tissues, to identify, characterize, and quantify all biological molecules that are involved in the structure, function, and dynamics of a cell, tissue, or organism. Examples include proteomics, transcriptomics, genomics, metabolomics, lipidomics, and epigenomics, which correspond to global analyses of proteins, RNA, genes, metabolites, lipids, and methylated DNA or modified proteins in chromosomes, respectively.

Acute - symptoms or conditions that occur suddenly and/or last a relatively short period of time. The length of time depends on the illness, but typically lasts a day or two, or a week or so, but not months

Anastomosis - a surgical connection between two structures. It usually means a connection that is created between tubular structures, such as blood vessels or loops of intestine

Ascites - the build-up of fluid in the space between the lining of the abdomen and abdominal organs. The most common causes of ascites are cirrhosis, heart failure, and cancer. Ascites results from high pressure in the blood vessels of the liver (portal hypertension)

Asymptomatic - a disease or condition showing no symptoms

Anti-TNF Medications – anti-tumor necrosis factor medications, including infliximab or adalimumab, may be used to block TNF in patients with inflammatory bowel disease that is not responding to conventional medications (corticosteroids, immunomodulators)

Atypical - an unusual or abnormal finding or symptom

Autoimmunity - refers to immune system overactivity, where the body attacks and damages its own tissues (autoimmune disease). This is currently being studied as a factor contributing to the development of PSC, along with genetic and environmental factors

Bacterial cholangitis - a bacterial infection in the bile ducts

Bile - a liquid made by the liver, containing water, cholesterol, bile salts, electrolytes, and waste products such as bilirubin. Bile is stored in the gallbladder and passes through the bile ducts into the intestine where it helps digest fat

Bile ducts - the tube-like structures that carry bile from the liver to the intestines

Biliary system - also called biliary tree or biliary tract, refers to the liver, gall bladder and bile ducts which creates, moves, stores, and releases bile into the small intestine

Bilirubin – an orange-yellow substance made during the normal process when red blood cells break down. Bilirubin goes through the liver, mixing with bile, and then is removed from the body through the stool (feces)

Calcifications - calcium build up in body tissue, causing the tissue to harden. This can be a normal or abnormal process and can be visible through X-rays.

Cholangiocarcinoma (CCA) - a rare cancerous (malignant) growth in one of the bile ducts

Cholangiography - the imaging of the bile ducts by x-rays aided by the injection of a dye

Cholangitis - inflammation of one or more bile ducts. Cholangitis may be caused by a bacterial infection, a blockage caused by gallstone(s) in the biliary tree, or a blockage caused unintentionally from manipulation during a medical procedure

Cholestasis - reduction or stoppage of bile flow. Disorders of the liver, bile duct, or pancreas can cause cholestasis, as can certain medications

Choledocholithiasis - biliary stones or gallstones in the bile ducts. Stones may form when there is a high level of cholesterol or bilirubin in the bile. Calcium salts may also form stones

Chronic - refers to something that continues over a long period of time or often recurs. A chronic condition usually does not go away easily or quickly. Chronic is the opposite of acute

Cirrhosis - a late stage of scarring (fibrosis) of the liver caused by many forms of liver diseases

Comorbidity - two health conditions that are present at the same time, such as PSC and IBD

Crohn’s Disease – a type of inflammatory bowel disease, Crohn’s most commonly affects the end of the small bowel (the ileum) and the beginning of the colon, but it may affect any part of the gastrointestinal (GI) tract

DEXA/DXA - a bone densitometry scan using a small dose of radiation to produce pictures of the inside of the body (usually the lower (or lumbar) spine and hips) to measure bone loss. Often used to evaluate osteoporosis. Also called dual-energy x-ray absorptiometry

Diagnosis of Exclusion - a diagnosis of a medical condition reached by a process of elimination, which may be necessary if the condition cannot be confirmed with testing. Sometimes the diagnosis of exclusion is made by careful detective work during the history and physical examination, reviewing symptom patterns, and excluding other known diseases

Dys - a prefix used to convey the idea of being difficult, impaired or abnormal

Edema - swelling or puffiness caused by excess fluid trapped in your body's tissues, often seen in the hands, ankles and feet

Epidemiology - the study of patterns, frequencies, causes and risk factors of how often diseases or health-related events occur in different groups of people and why. In the case of PSC, epidemiology helps to understand disease prevalence

Endoscopy - also called esophagogastroduodenoscopy, a nonsurgical procedure used to examine a person's digestive tract. Using an endoscope, a flexible tube with a light and camera attached to it, the doctor can view the digestive tract and perform certain procedures, such as a biopsy or stent (tube). Endoscopic ultrasound (EUS) uses ultrasound during endoscopy

ERCP - Endoscopic Retrograde Cholangiopancreatography is a procedure using an endoscope to see and diagnose diseases of the gallbladder, biliary system, pancreas, and liver. The test looks "upstream" where digestive fluid comes from -- the liver, gallbladder, and pancreas -- to where it enters the small intestines. If there is a blockage, a stent (tube) may be placed

Extrahepatic - situated or originating outside the liver

Fecal microbiota transplant (FMT) - the procedure in which stool from a healthy donor is placed into the gut of a patient in order to treat some conditions. This procedure is typically done via colonoscopy

Fibrosis - scarring of the liver tissues when the liver tries to repair and replace damaged or inflamed cells. Scar tissue does not work as well as healthy liver tissue

Genotype - the set of genes that make up a cell or an individual or an organism. Genotype can also refer to a particular gene or set of genes carried by an individual

Graft - a piece of living tissue that is surgically transplanted

Hepatic Encephalopathy (HE) - deterioration of brain function that occurs in people with severe liver disease, also called “brain fog.” HE is caused when toxins that are normally cleared from the body by the liver build up in the blood, and eventually affect the brain

Hepatitis – an inflammation of the liver, commonly caused by a viral infection, but also may be from autoimmune disease, or as a result of other infections, medications, or toxic substances (alcohol or certain drugs)

Hepatomegaly - an enlarged liver

Hyper (prefix) - excessive or increased beyond normal

Hyperplasia – an increase in the number of cells in an organ or tissue. These cells look normal under a microscope. The cells are not cancer but may become cancer

Hypo (prefix) - less than normal, deficient, a lack of, or shortage

Idiopathic - of unknown cause. Any disease or condition with uncertain origin or where the cause is unknown

Immunomodulators - medications to help regulate or normalize the immune system, such as azathioprine, methotrexate, or sulfasalazine

Immunosuppression - suppression of the body’s immune system, reducing its ability to fight infections and other diseases. The body's immune system may be intentionally stopped from working, or is made less effective, usually by drugs, to help the body accept an organ that has been transplanted. Immunosuppression may also result from some diseases or medications

Inflammatory bowel disease (IBD) - an umbrella term used to describe disorders that involve chronic inflammation of the digestive tract, such as ulcerative colitis and Crohn’s disease. Symptoms of ulcerative colitis and Crohn’s can include severe diarrhea, bloody stools, abdominal pain, fatigue, and weight loss

International normalized ratio (INR) - is a test used to measure how quickly a patient's blood forms a clot, compared with normal clotting time. It is also know as prothrombin time (PT) test. Prothrombin is a protein produced by the liver. When liver disease is suspected, a medical provider may use an INR to test liver function. A high INR may mean that the liver is not working as well as it could, because it is not making the blood clot normally. This test is also commonly used to measure the effectiveness of blood thinners.

Interventional Radiology (IR) - uses minimally-invasive, image-guided procedures to diagnose and treat medical conditions that may have required open surgery. IR utilizes ultrasound, X-rays, CAT scans, MRI scans or other innovative imaging methods

Itis (suffix) - refers to inflammation, e.g. cholangitis or colitis

Jaundice - a condition in which the skin, whites of the eyes and mucous membranes turn yellow because of a high level of bilirubin, a yellow-orange bile pigment. Jaundice has many causes, including liver disease (hepatitis), gallstones, blockage of the bile ducts, blood disorders, and tumors, as well as a disease called Gilbert’s syndrome, or medication side effects

Liver Biopsy - a small sample of liver tissue is removed by inserting a special needle through the abdominal wall and into the liver. Ultrasound guidance is often used and numbing medicine is applied before the needle is placed. The tissue can then be examined under a microscope for signs of damage or disease, to help decide the best treatment, or to find out how a treatment for liver disease is working

Lesion - a region in an organ or tissue which has suffered damage through injury or disease

MELD - Model for End-Stage Liver Disease is a method to identify who most needs a liver transplant for patients with chronic liver disease. The MELD score includes the laboratory values of bilirubin, creatinine, and international normalized ratio (INR), and sodium. For children under 12, the PELD (Pediatric End-Stage Liver Disease) score is used to indicate disease severity

Metabolic bone disease - umbrella term for any of several diseases that cause various abnormalities or deformities of bone, with the most common being osteoporosis, a disease where the bones become weak and brittle

Microbiome/Microbiota - The human microbiota consists of the 10-100 trillion symbiotic (involving beneficial or harmful interaction among cells) microbial cells harbored by each person, primarily bacteria in the gut; the human microbiome consists of the genes these cells harbor

MRCP - Magnetic Resonance Cholangiopancreatography is a non-invasive exam with a special type of magnetic resonance imaging (MRI) to show detailed images of the hepatobiliary and pancreatic systems, including the liver, gallbladder, bile ducts, pancreas, and pancreatic duct

Necrosis - death of cells or tissue through disease or injury

Nodule - a growth or lump of tissue that can be felt either under the skin or deeper in the body, that may be malignant (cancer) or benign (not cancer)

Pathology - the study of the causes and effects of disease or injury, especially the medical specialty that deals with the laboratory examination and diagnosis of body tissue samples

Patient Reported Outcome (PRO) - is an outcome directly reported by the patient and pertains to the patient’s health, quality of life, or functional status associated with health care or treatment. This places patients at the center of health care research and clinical care evaluation. Patient outcomes may include general health, ability to complete various activities, mood, level of fatigue, or pain

Phenotype - the observable physical characteristics or traits that result from the interaction of the genotype (set of genes responsible for a trait) with the environment, such as height, eye color, overall health, disease history, and behavior

Prebiotics - foods, typically high fiber, that act as food to promote the growth of beneficial microorganisms in the intestines

Probiotics - live microorganisms that when administered in adequate amounts, can confer a health benefit on the person by improving or restoring the gut flora

Plasty (suffix) - surgical procedures that repair, replace, restore or improve a part of the body

Portal hypertension - an increase in the pressure within the portal vein (the vein that carries blood from the digestive organs to the liver). A blockage in the blood flow through the liver, such as from cirrhosis (scarring) or blood clots in the portal vein, can cause portal hypertension.

Pruritus - localized or generalized itching, a prevalent and distressing symptom of cholestasis

Registry - a standardized database of medical data that can include information such as diagnosis, family history, medications, surgeries, quality of life, and test results. Often registries are disease-specific and data can be either patient reported or physician reported

Rejection (post-transplant) - occurs when the immune system of the recipient of a transplant attacks the transplanted organ or tissue. This is because a normal, healthy human immune system can distinguish foreign tissues and attempts to destroy them, just as it attempts to destroy infective organisms such as bacteria and viruses. Immunosuppressant (anti-rejection) medications help prevent the immune system from attacking (“rejecting”) the donor organ

PSC Partners Patient Registry - a patient-driven, patient-reported registry that serves to facilitate PSC research and clinical trials

Sclerosis - stiffening or abnormal hardening of a body tissue

Splenomegaly - an abnormal enlargement of the spleen

Stent - a short, narrow metal or plastic tube, often in the form of a mesh, that is inserted into a blood vessel or bile duct to keep a blocked passageway open

Stricture - an abnormal narrowing of a body passage, especially a tube or canal like the bile duct, which can slow or obstruct the flow of body fluids. Inflammation, cancer, or scar tissue may cause a stricture

Transient Elastography (TE, Fibroscan) - a non-invasive test using a specialized ultrasound machine and low-frequency elastic waves to assess the hardness (or stiffness) of the liver and estimate the degree of liver fibrosis or cirrhosis

Ultrasound - a radiation-free imaging method that uses high-frequency sound waves which reflect off body structures to create images (pictures) of the inside of your body

Ulcerative colitis - an inflammatory bowel disease that causes long-lasting inflammation and sores (ulcers) in the innermost lining of the large intestine (colon) and rectum. PSC is often associated with ulcerative colitis

Xanthomas - fatty, irregular, yellow patches or nodules containing lipid-filled cells occurring on skin (e.g. eyelids, neck, back) or internal tissue, often associated with disturbances of lipid (fat) metabolism. If caused by an underlying medical condition, such as high cholesterol, diabetes, cholestasis, or medication side effects, the cause should be addressed



5-ASA5-aminosalicylic acid
AIH-autoimmune hepatitis
ALP-alkaline phosphatase
ALT-alanine aminotransferase
AST-aspartate aminotransferase
CA19-9-carbohydrate antigen 19-9
CBD-common bile duct
CC or CCA-cholangiocarcinoma
CD-Crohn’s disease
CEA-carcinoembryonic antigen
ERCP-endoscopic retrograde cholangiopancreatography
FNA-fine needle aspiration
FISH-fluorescent in-situ hybridization
HA-hepatic artery
HE-hepatic encephalopathy
IBD-inflammatory bowel disease
INR-international normalized ratio
LFT-liver function test
LT-liver transplantation
MRCP-magnetic resonance cholangiopancreatography
PBC-primary biliary cholangitis (previously known as primary biliary cirrhosis)
PSC-primary sclerosing cholangitis
PTT-prothrombin time
RUQ or URQ-upper right quadrant or torso

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