The terms listed here are defined in the context of Sjogren’s.
ANA - See Antinuclear Antibody
ANA - See Antinuclear Antibody
A protein produced by a type of B cell lymphocyte, usually in response an infection. Antibodies are also referred to as immunoglobulins such as IgG, IgM, etc. See also Autoantibodies.
A ring-shaped skin rash found in 10% of people with Sjogren’s.
A substance that can be recognized by the immune system, usually a foreign invader such as a virus or bacterium. If the antigen is part of the body, it is called an autoantigen.
Joint pain and stiffness. This impacts more than 50% of Sjogren’s patients. May or may not be accompanied by inflammatory arthritis.
Antinuclear Antibodies (ANA)
Autoantibodies directed against components in the cell nucleus. Blood tests for ANA are almost always positive in SLE and Systemic Sclerosis. ANA is positive in 50-70 % of Sjogren’s patients. ANA is occasionally seen in healthy individuals, or triggered by certain infections or medications.
Antibodies that target the body’s own tissue.
A part of the body that is targeted by an autoantibody (or certain types of T cells).
A disease or condition is present but there are no obvious symptoms.
A type of immune-mediated disease where the body inappropriately produces antibodies against its own tissues. The role that autoantibodies play in Sjogren’s is unclear. Sjogren’s is considered to be an autoimmune disease, although it is probably more precise to call it "immune-mediated." For an explanation, see the blog post, So What is Sjogren’s, Really?
Organ-specific autoimmune diseases, such as autoimmune thyroid disease or type I diabetes, attack one specific organ. (The thyroid and the pancreas in these examples)
Systemic autoimmune diseases, such as Sjogren’s and rheumatoid arthritis attack multiple areas of the body.
Autoimmune Rheumatic Disease (AIRD)
An autoimmune disease that is systemic and involves connective tissues, organs and other areas of the body. Sjogren’s is included in this group of diseases, along with rheumatoid arthritis and others. Some AIRDs may not be purely autoimmune. For details, see the blog post, So What is Sjogren’s, Really?
A characteristic or indicator, that can be objectively measured.
A group of symptoms that describe difficulty thinking. There are many possible causes. The few studies on Sjogren’s patients document cognitive changes, mostly mild, with reduced concentration, memory, and/or executive function. More than 50% of Sjogren’s patients experience brain fog.
A broad term for diseases that impact the heart and blood vessels. Common cardiovascular comorbidities in Sjogren’s include coronary artery disease, cerebrovascular disease (e.g. strokes), hypertension, and deep venous thrombosis. Vasculitis, a direct Sjogren’s manifestation, is technically a vascular disease, but is usually categorized according to the body system impacted (e.g., skin, brain, heart, etc.).
Diseases associated with Sjogren’s but not caused directly by Sjogren’s. Comorbidities are also called "associated diseases" because they occur at higher rates in Sjogren’s patients than in the population as a whole.
Central Nervous System
The brain and spinal cord
Complement, C3 and C4
Complement is a group of proteins that play a complex role in the regulation of the immune system. Abnormal function of the complement system may play a role in the clinical expression of Sjogren’s and related diseases. In Sjogren’s, low C3 and C4 are associated with increased risk of severe disease
COPD- Chronic Obstructive Pulmonary Disease
A lung disease that causes less air flow in and out of the airways, making it hard to breathe. While COPD is typically occurs in smokers, it also impacts a significant number of Sjogren’s patients who have never smoked (158).
Connective Tissue Disease (CTD)
A broad term for disorders involving tissues that support the organs and other parts of the body. Examples of connective tissue include cartilage, synovium (the joint lining), tendons, ligaments, fat, bone and many of the structures that support the skin. Sjogren’s is considered to be a connective tissue disease, although it also impacts the exocrine glands and many organs and systems. Rheumatologists care for many, but not all, types of CTD.
On Sjogren’s Advocate and in most academic articles, complications refer to direct systemic (non-sicca) disease manifestations of Sjogren’s, not including general systemic features.
Damage or dysfunction of one or more cranial nerves. The cranial nerves arise directly from the brain. Trigeminal sensory neuropathy is thought to be the most common form of cranial neuropathy in Sjogren’s
Protein complexes circulating in the blood that are precipitated during cold. These can cause immune complex-mediated vasculitis, which can be severe or even life-threatening. Cryoglobulins are important prognostic indicators in Sjogren’s, associated with worsened outcomes and increased lymphoma risk.
Low number of various types of blood cells. Anemia occurs when red blood cells counts are low, Leukopenia refers to low numbers of white blood cells. Thrombocytopenia is a deficiency of platelets. Pancytopenia is a deficiency of all three parts of the blood.
A persistent state of imbalance of microorganisms on or within our bodies. While the term is often equated with altered gut bacteria, dysbiosis many also impact other parts of the body and involve other organisms such as fungi and viruses. Severe intestinal dysbiosis occurs in about 20% of people with Sjogren’s.
Abnormal function of the muscles of the gastrointestinal tract. All types of gastrointestinal dysmotility are common in Sjogren’s, resulting in constipation, diarrhea, dysphagia and gastroparesis.
Trouble swallowing. In Sjogren’s, this is often caused by dysmotility and reflux, made worse by dryness.
dRTA- Distal Renal Tubular Acidosis
A kidney malfunction, often asymptomatic, that occurs in 10-40% of Sjogren’s patients. In dRTA, the kidneys do not properly remove acids from the blood. This leads to electrolyte disturbance which may weaken bones or cause kidney stones. dRTA is often the first sign of TIN.
ESSDAI- EULAR Sjogren’s Syndrome Disease Activity Index
“EULAR” stands for the European League Against Rheumatism. The ESSDAI is a standardized scoring system that rates 12 specific “domains” of systemic manifestations. This is the primary tool that Sjogren’s researchers use to measure overall disease activity. Click here for more information.
Features / Manifestations
Signs and symptoms caused directly by Sjogren’s. On Sjogren’s Advocate, features and manifestations mean the same thing.
Functional Neurologic Disorder (FND)
Nervous system (neurological) symptoms that can't be explained by a neurological disease or other medical condition. Many people with undiagnosed conditions, especially SFN, SFPN, and dysautonomia are labeled with FND.
A disorder of chronic, widespread pain and tenderness, fatigue, unrefreshed sleep, and cognitive dysfunction. It is a diagnosis of exclusion; this means that patients should be thoroughly evaluated for other disorders, such as Sjogren’s. If you have Sjogren’s, the fibromyalgia label should be dropped.
Gamma Globulin- IgG (mostly)
IgG is the major immunoglobulin (antibody) type in blood and other body fluids. It is a key player in the part of the immune system that secretes antibodies in response to a specific antigen. Gamma globulin usually refers to IgG, but technically may include other proteins and antibodies.
General Systemic Features
Core Sjogren’s features such as severe physical fatigue, flu-like malaise, brain fog (difficulty with concentration and memory), widespread body aches, muscle pain and stiffness. General systemic features are often mislabeled fibromyalgia even though they are direct Sjogren’s manifestations. These core features are poorly researched and poorly understood, yet account for the greatest reduction in function and quality of life for most patients. Read more...
GERD- Gastroesophageal Reflux Disease
A severe type of kidney disease, impacting about 2% of Sjogren’s patients over time. Usually associated with low complement and cryoglobulins. Unlike TIN, it often has a sudden onset.
Health Related Quality of Life (HRQOL)
An overall assessment of an individual's or a group's perceived physical and mental wellbeing over time. There are various formal tools that assess HRQOL in individuals and populations.
HRCT- High Resolution Computerized Tomography (CAT Scan)
Elevated levels of immunoglobulins in the blood. In Sjogren’s this is almost always due to elevation of a number of types of IgG (“polyclonal” hypergammaglobulinemia). Immunoglobulin types are measured by the Serum Protein Electrophoresis (SPEP) test. Hypergammaglobulinemia is a common systemic manifestation of Sjogren’s. It often causes an elevated erythrocyte sedimentation rate (ESR).
Reduced levels of gamma globulins, or IgG, in the blood. This is an uncommon systemic manifestation of Sjogren’s.
ILD- Interstitial Lung Disease
Inflammation and scarring of the lung tissue. This is a common but underdiagnosed complication of Sjogren’s. Many cases of “idiopathic” ILD are actually undiagnosed Sjogren’s.
Click here to learn more about Sjogren’s lung disease and find links to the Pulmonary Clinical Practice Guidelines.
This is actually the correct term to use for “the body attacking self” vs. the more commonly used term, “autoimmune”. Immune-mediated diseases include both autoimmune and autoinflammatory processes. Sjogren’s is an immune-mediated disease. For details see the blog post, So What is Sjogren’s, Really?
A complex network of cells, proteins and tissues that defends the body against infection.
The immune system is elaborate and complicated. There are still many unknowns about how the immune system works and why it sometimes turns against the body.
Generally speaking, this refers to antibodies, although the technical definition is more complicated. The five main classes are IgG, IgM, IgA, IgD and IgE. Each class functions in different types of immune responses. Click here for more information.
Immunoglobulin G- IgG
Disease fighting glycoproteins made by plasma B cells. Glycoproteins are proteins with a type of sugar attached to them. IgG is one of the five major types of immunoglobulins.
A biological response that occurs when the immune system sends out inflammatory cells and messengers (e.g., cytokines) to attack an offending agent. This is a normal response to outside insults such as infection or trauma. In immune-mediated inflammatory disorders such as Sjogren’s, the immune system attacks the body’s own cells or tissues.
Please note: Inflammation can be measured many ways. In Sjogren’s the CRP and ESR do not correlate with Sjogren’s disease activity or severity or overall inflammation.
Joint inflammation caused by the immune system attacking the joint. This is different from osteoarthritis which is caused by wearing away of the joint cartilage. Tenderness and swelling of the joints usually indicate inflammatory arthritis.
Interstitial Nephritis- see TIN
ITP-Immune Thrombocytopenic Purpura
A blood disorder characterized by a decrease in the number of platelets in the blood.
LFN- Large Fiber Neuropathy
Malfunction of the large nerve fibers caused by damage to the axon or the myelin sheath that wraps around the axon. Damage can be detected by a typical neurologic examination and nerve conduction studies, unlike the damage caused by small fiber neuropathy.
Click here for more information about types of neuropathies.
Abnormally enlarged lymph nodes.
Manifestations / Features
Signs and/or symptoms caused directly by Sjogren’s. On Sjogren’s Advocate, manifestations and features mean the same thing.
MCI- Mild cognitive impairment
Many Sjogren’s patients are misdiagnosed with ME/CFS because of symptom overlap, including dysautonomia and extreme fatigue. It is possible, although not likely, to have both. It is important to distinguish the two conditions because treatments and exercise recommendations differ .See this link for a description.
MGUS- Monoclonal Gammopathy of Undetermined Significance
A non-cancerous condition where the body makes an abnormal protein, called M protein. MGUS is sometimes found in Sjogren’s and other rheumatology patients. It does not require treatment, but should be monitored because it can be a precursor to multiple myeloma.
Click here for more information.
Morbidity (not to be confused with mortality or comorbidity)
Refers to illness, or more broadly, any condition that reduces health or wellbeing. It is commonly used to indicate the amount of disease (prevalence) within a population. Morbidities are not deaths.
Sjogren’s is associated with a high degree of functional morbidity.
Lung disease, arthritis, sicca, and peripheral neuropathies are common Sjogren’s morbidities.
In medicine, mortality usually means mortality rate. This describes the number of deaths that occur in a population due to a specific illness or condition.
A cancer of blood cells called plasma cells. It is a rare complication of Sjogren’s.
A disease involving more than one organ or system in the body. “System” includes any organ (the skin is also an organ) or body system (such as the nervous system, hematology system).
Nerve conduction studies
These tests evaluate the electrical conduction of the myelinated motor and sensory nerves. Because they do not test for small unmyelinated nerve function, they cannot rule out SFN, SFPN, or dysautonomia.
Nephrogenic DI (diabetes insipidus)
Nephrogenic DI is caused when the kidneys don’t properly concentrate urine. It is not related to blood sugar. People with DI often are dehydrated and low on electrolytes such as such as sodium, potassium or calcium. It is often overlooked in Sjogren’s patients because excess water intake prompted by dehydration is attributed to sicca.
Pertaining to the nervous system, either the central nervous system or the peripheral nervous system.
Peripheral nervous system
The part of the nervous system outside the brain and spinal cord.
Disease or dysfunction of the peripheral nervous system.
PAH- Pulmonary (arterial) hypertension .
Pulmonary arterial hypertension damages the blood vessels in the lungs, causing high blood pressure in the lung arteries. This may cause the heart to become weak and fail. This uncommon but serious Sjogren’s complication may be fatal.
PBC-Primary biliary cholangitis (previously called primary biliary cirrhosis)
Impacting 2-5% of Sjogren’s patients, PBC is a chronic autoimmune liver disease resulting from progressive destruction of the bile ducts in the liver. See this link for more information.
PNS- peripheral nervous system
The part of the nervous system outside of the brain and spinal cord.
Lung disease. Pulmonary refers to the lungs.
Raynaud’s (Raynaud’s phenomenon)I
A condition that causes by narrowing of the small arteries that supply blood to the fingers or toes (occasionally other parts of the body), causing them to feel numb and cold in response to cold temperatures. 15-30 % of people with Sjogren’s have this systemic Sjogren’s feature.
RA- See Rheumatoid Arthritis
Kidney disease (renal refers to kidney)
RF- See Rheumatoid Factor
Immune-mediated and inflammatory diseases that cause the immune system to attack normal tissues in body, including joints, muscles, bones and organs. Rheumatic diseases are often grouped under the term “arthritis” - which is used to describe over 100 diseases and conditions. Sometimes called rheumatologic disease.
Rheumatoid Factor (RF)
An autoantibody present in the blood of most patients with rheumatoid arthritis (RA) and Sjogren's. RF may be detected in some healthy people. A significant number (30-40%) of people with RA and Sjogren’s do not have rheumatoid factor. NOTE: This should not be called "RA factor".
Rheumatologists are the specialists who are supposed to take the lead in treating Sjogren’s and other rheumatic diseases.
"A rheumatologist is an internist or pediatrician who received further training in the diagnosis (detection) and treatment of musculoskeletal disease and systemic autoimmune conditions commonly referred to as rheumatic diseases. These diseases can affect the joints, muscles, and bones causing pain, swelling, stiffness, and deformity." ~ American College of Rheumatology
Rheumatoid Arthritis (RA)
A systemic autoimmune rheumatic disease that mainly attacks the joints, especially in the wrists and hands. Sjogren’s patients who have inflammatory arthritis are sometimes misdiagnosed with RA, or they may have both Sjogren’s and RA.
This term is used by researchers and Sjogren's experts to refer to SS-A positive Sjogren’s patients. In the real world, “seropositive” is used much more loosely. Some rheumatologists will call SS-A or SS-B positive patients seropositive. Others will call patients seropositive if they have any of the following: SS-A, SS-B, ANA, or RF.
Many primary care providers are not familiar with Sjogren’s-related autoantibodies, including SS-A. They might use “seropositive” to mean RF-positive Sjogren’s.
In Sjogren’s, this technically refers to SS-A negative patients. Rheumatologists often use the term “seronegative” based their own preferences about which common autoantibodies count as seropositive. Common autoantibodies associated with Sjogren’s include SS-A, ANA, SS-B, and RF.
Many primary care providers use “seronegative” to mean any RF-negative rheumatology patient. This can be very confusing.
This is a general term for whether a blood test is positive or negative. In Sjogren’s, “serostatus” usually refers to whether typical autoantibodies are present.
SFN - See small fiber neuropathy
SFPN - See small fiber polyneuropathy
SIBO- Small Intestine Bacterial Overgrowth
An increase in the overall bacterial population of the small intestine, especially by types of bacteria not commonly found in that part of the digestive tract.
Objective evidence of a disease or condition that is evident upon physical examination or as measured by various tests.
Sicca is the part of Sjogren’s that causes dryness, inflammation, and other abnormalities of the exocrine (fluid-secreting) glands in the body, such as tear and saliva glands. While most Sjogren’s patients have sicca, not all of them do. Sjogren’s should never be called “sicca syndrome”.
Sjogren's antibodies: SS-A (anti-Ro) and SS-B (anti-La)
SS-A (anti-Ro) and SS-B (anti-La) have been traditionally called Sjogren’s antibodies. This can be confusing because they may also be seen in other autoimmune rheumatic diseases. SS-A and SS-B are members of the family of antibodies called anti-nuclear antibodies (ANAs)
“Antibodies” in this case actually means autoantibodies. For details, see the blog post So What is Sjogren’s, Really?
SLE - See Systemic lupus erythematosus
Small fiber neuropathy
Small fibers are the unmyelinated nerves outside the brain and spinal cord that detect sensations and control autonomic functions such as heart rate, blood pressure, bowel motility, sweating, etc. Neuropathy means that these nerves are not working correctly. In SFN, the number of nerve fibers is often reduced on skin biopsy. Sensory neuropathy and autonomic neuropathies often occur together.
Small fiber polyneuropathy
Small fiber neuropathy that impacts widespread areas of the body and a large number of nerves. Because most SFNs impact widespread areas, the term small fiber neuropathy is often used to refer to small fiber polyneuropathy.
SMR-Standardized Mortality Ratio
“The ratio between the observed number of deaths in a study population and the number of deaths would be expected, based on the age- and sex-specific rates in a standard population and the population size of the study population by the same age/sex groups. If the ratio of observed: expected deaths is greater than 1.0, there is said to be "excess deaths" in the study population.”
SS-A and SS-B - See Sjogren's antibodies
Subjective experience of the patient which may or may not be associated with signs.
Systemic lupus erythematosus (SLE)
An autoimmune rheumatic disease closely related to Sjögren’s. Like Sjogren’s,SLE may damage any organ or body system. While these diseases carry similar features, SLE and Sjogren’s each has its own spectrum of clinical manifestations. When they occur together, each disease deserves separate attention and management.
Read more about why Sjogren’s should never be called “secondary” to SLE or other diseases.
Systemic Manifestations / Features
Any non-sicca disease manifestation caused by Sjogren’s.
In Sjogren’s, the confusing convention is to divide the disease manifestations into two categories: sicca manifestations and systemic (non-sicca) manifestations. This may seem illogical and contradictory because the word “systemic” in medicine usually describes something that impacts multiple areas of the body and sicca impacts multiple exocrine glands in the body. Even so, in Sjogren’s, sicca is not considered systemic.
Many rheumatologists will tell their patients that they just have sicca disease. This is not correct because non-sicca (systemic) manifestations can be found in almost every Sjogren's patient. Read more…
The most common type of kidney disease caused by Sjogren’s, usually slowly progressive and easily missed early in the disease. Mild versions occur in up to 50 % of Sjogren’s patients. The first sign of TIN is often electrolyte disturbance caused by dRTA. See this link for more information.
Inflammation and/or destruction of blood vessel walls. Sjogren’s-related vasculitis includes cutaneous vasculitis, vasculitic neuropathy (often acute onset), and cerebral vasculopathy. Vasculitis may be systemic and involve almost any part of the body. Vasculitis is a marker of systemic disease activity included in the ESSDAI. Click here for more information.
Abnormally dry skin.