Skip to main content

IGGR4

 IGGR4



overview

IgG4-related disease (IgG4-RD) is a chronic, fibro-inflammatory condition affecting multiple organs, characterized by the infiltration of IgG4-positive plasma cells, fibrosis, and elevated serum IgG4 levels. It can mimic tumors, infections, or other immune-mediated diseases, making diagnosis challenging. 

Symptoms

Fatigue: Persistent and unexplained tiredness.

Weight Loss: Unexplained loss of weight, sometimes significant.

Lymphadenopathy: Enlarged lymph nodes, often symmetrical and involving multiple areas like the neck, axillae, or mediastinum.

Low-grade fever: A persistent, but not very high, fever. 

Organ-Specific Symptoms:

Pancreas: Abdominal pain, nausea, jaundice (if bile ducts are affected), or symptoms of pancreatic insufficiency (e.g., gas, diarrhea, weight loss). 

Salivary and Lacrimal Glands: Dry eyes and dry mouth. 

Bile Ducts: Jaundice, abdominal pain. 

Kidneys: Flank pain, kidney dysfunction. 

Lungs: Shortness of breath. 

Nervous System: Headaches, cranial nerve dysfunction (e.g., double vision, facial numbness), and rarely, motor weakness or limb numbness. 

Heart and Aorta: Symptoms of coronary artery disease or aortic aneurysms. 

Retroperitoneum: Can cause ureteral obstruction leading to flank pain, kidney damage, or aortic aneurysms. 

Eyes: Bulging eyes or eye discomfort. 

Cause

1. Immune System Involvement:

IgG4-RD is characterized by an abnormal immune response, where the body produces excessive IgG4 antibodies and infiltrates affected tissues with IgG4-positive plasma cells. 

This immune response leads to chronic inflammation and fibrosis (scarring) in various organs. 

While the specific triggers for this immune response are not fully understood, it's believed to involve a complex interplay of genetic, environmental, and potentially infectious factors. 

2. Potential Contributing Factors:

Genetic Predisposition:

Certain genetic factors, such as specific HLA haplotypes, have been associated with IgG4-RD in some populations. 

Environmental Factors:

Smoking is a well-established risk factor for retroperitoneal fibrosis, a type of IgG4-RD. Exposure to certain substances like solvents and metal dusts has also been suggested as a potential risk factor. 

Autoimmunity:

IgG4-RD is considered an autoimmune disease, meaning the immune system mistakenly attacks the body's own tissues. 

Infections:

While not definitively proven, some studies suggest that certain infections, like E. coli and H. pylori, may play a role in triggering the disease, possibly through molecular mimicry (where the body's immune system reacts to a foreign antigen that resembles a self-antigen). 

3. Ongoing Research:

Research is ongoing to identify the specific autoantigens (self-antigens that are targeted by the immune system) and the precise mechanisms that drive the disease process. 

Studies are also exploring the roles of different immune cells, such as T cells and B cells, in the pathogenesis of IgG4-RD. 

In summary, while the exact cause of IgG4-RD is still unknown, it is understood to be an immune-mediated condition likely triggered by a combination of genetic, environmental, and potentially infectious factors, leading to chronic inflammation and fibrosis in various organs. 

1. Clinical Evaluation:

A thorough history and physical exam are essential, paying attention to potential symptoms like swelling, pain, or organ dysfunction related to affected areas. 

2. Laboratory Tests:

Serum IgG4 levels: While helpful, elevated levels alone are not sufficient for diagnosis. 

Other blood tests: May include CBC with differential (for eosinophilia), complement levels (for kidney involvement), and other tests depending on suspected organ involvement. 

3. Imaging:

Radiological findings can be suggestive of IgG4-RD, but are often not definitive on their own. 

Examples: MRI, CT scans, or ultrasound may show organ enlargement, masses, or other abnormalities. 

4. Histopathology:

Biopsy of affected organs: Provides the most definitive evidence of IgG4-RD. 

Characteristic findings: Include lymphoplasmacytic infiltration, storiform fibrosis, and obliterative phlebitis. 

Immunostaining: Confirms the presence of IgG4-positive plasma cells in the tissue. 

5. Exclusion of Mimickers:

It is crucial to rule out other conditions that can mimic IgG4-RD, such as cancer or infections. 

Organ-Specific Considerations:

In some cases, like Autoimmune Pancreatitis (AIP), radiological features may be sufficiently specific to suggest IgG4-RD, potentially reducing the need for biopsy. 

Different organs may have slightly varying histological criteria for IgG4-RD diagnosis. 

In summary, the diagnosis of IgG4-RD involves a multi-faceted approach, with histopathology playing a key role. A careful evaluation of clinical findings, imaging results, and laboratory data, alongside the exclusion of other potential diagnoses, leads to a definitive diagnosis. 

Treatment

The initial recommended dose of oral prednisolone for induction of remission is 0.6 mg/kg/day, administered for 2-4 weeks. This dose is gradually tapered to a maintenance dose of 2.5-5 mg/day over a period of 2-3 months.

Type of Doctor Department : Gastroenterologists, rheumatologists, and ophthalmologists


Comments

Post a Comment

Popular posts from this blog

Charge Syndrome

Overview CHARGE syndrome is a recognizable genetic syndrome with known pattern of features. It is an extremely complex syndrome, involving extensive medical and physical difficulties that differ from child to child. CHARGE syndrome is correlated with genetic mutation to CHD7 and the prevalence of CHARGE syndrome is 1:10,000-1:15,000 live births. Babies with CHARGE syndrome are often born with life-threatening birth defects. They spend many months in the hospital and undergo many surgeries and other treatments. Swallowing and breathing problems make life difficult even when they come home. Most have hearing two little girls sitting on a carpet, one girl has a trach and is biting her finger.loss, vision loss, and balance problems that delay their development and communication. Despite these seemingly insurmountable obstacles, children with CHARGE syndrome often far surpass their medical, physical, educational, and social expectations. One of the hidden features of CHARGE syndrome is the ...
7 comments
Read more

Acral Peeling Skin Syndrome

Overview Acral peeling skin syndrome is a skin disorder characterized by painless peeling of the top layer of skin. The term "acral" refers to the fact that the skin peeling in this condition is most apparent on the hands and feet. Occasionally, peeling also occurs on the arms and legs. The peeling is usually evident from birth, although the condition can also begin in childhood or later in life. Skin peeling is made worse by exposure to heat, humidity and other forms of moisture, and friction. The underlying skin may be temporarily red and itchy, but it typically heals without scarring. Acral peeling skin syndrome is not associated with any other health problems. Symptoms The main symptom of APSS is the painless peeling of the skin. Most people can remove this skin by hand, and it may come off in sheets, similar to peeling skin after a sunburn. 1. blistering 2. itching 3. easily removable hairs If a person exposes their skin to heat, sweat, or water, they may notice that the...
Post a Comment
Read more

Sjogren's syndrome

Sjogren's syndrome Overview Sjogren's (SHOW-grins) syndrome is a disorder of your immune system identified by its two most common symptoms — dry eyes and a dry mouth. The condition often accompanies other immune system disorders, such as rheumatoid arthritis and lupus. In Sjogren's syndrome, the mucous membranes and moisture-secreting glands of your eyes and mouth are usually affected first — resulting in decreased tears and saliva. Although you can develop Sjogren's syndrome at any age, most people are older than 40 at the time of diagnosis. The condition is much more common in women. Treatment focuses on relieving symptoms. Symptoms The two main symptoms of Sjogren's syndrome are: Dry eyes . Your eyes might burn, itch or feel gritty — as if there's sand in them. Dry mouth. Your mouth might feel like it's full of cotton, making it difficult to swallow or speak. Some people with Sjogren's syndrome also have one or more of the following: Joint pain, swel...
Post a Comment
Read more