immunodeficiency with hyper-IgM type 2

Hyper-IgM Syndrome Type 2 (HIGM2) Overview

Hyper-IgM syndrome type 2, also known as HIGM2, is a rare immunodeficiency disorder characterized by normal or elevated levels of immunoglobulin M (IgM) in the blood and the absence or decreased levels of other immunoglobulins, such as IgG, IgA, and IgE.

Key Features

• Normal or elevated serum IgM levels
• Absence or decreased levels of IgG, IgA, and IgE
• Rare inherited primary immunodeficiency disease

Characteristics

HIGM2 is a rare condition that affects the immune system's ability to produce antibodies. The absence or decreased levels of other immunoglobulins make individuals with HIGM2 more susceptible to infections.

Prevalence and Susceptibility

Hyper-IgM syndromes, including HIGM2, are extremely rare, inherited primary immunodeficiency diseases. Individuals with HIGM2 may experience recurrent infections, particularly those caused by encapsulated bacteria such as Streptococcus pneumoniae and Haemophilus influenzae.

References

• [1] Dec 13, 2018 — Hyper IgM syndromes are a group of rare disorders in which the immune system does not function properly.
• [2] Hyper-IgM syndrome type 2 (HIGM2) is a rare immunodeficiency characterized by normal or elevated serum IgM levels with absence of IgG, IgA, and IgE.
• [4] Hyper IgM syndromes (HIGM) are characterized by decreased levels of immunoglobulin G (IgG) in the blood and normal or elevated levels of immunoglobulin M (IgM).
• [9] Hyper-IgM syndrome is an immunoglobulin (Ig) deficiency characterized by normal or elevated serum IgM levels and decreased levels or absence of other serum immunoglobulins.

Immunodeficiency with hyper-IgM (HIM) syndrome, specifically type 2, is a rare disorder characterized by recurrent infections associated with low IgG and IgA, and normal to increased IgM serum levels. The signs and symptoms of HIM type 2 can vary from one person to another.

Common Signs and Symptoms:

• Recurrent bacterial infections, such as pneumonia, sinusitis, and otitis media
• Increased susceptibility to opportunistic infections, including those caused by organisms that do not normally infect healthy individuals
• Low levels of IgG and IgA in the blood
• Normal or elevated levels of IgM in the blood
• Presence of autoimmune disorders, such as arthritis, low platelet counts (thrombocytopenia), anemia, hypothyroidism, and kidney disease

Other Possible Symptoms:

• Skin problems, such as eczema or psoriasis
• Gastrointestinal issues, such as diarrhea or abdominal pain
• Neurological symptoms, such as seizures or developmental delays

It's essential to note that the severity and type of symptoms can vary greatly among individuals with HIM type 2. A diagnosis is typically made based on clinical symptoms, family history, and laboratory tests.

References:

• [6] - This condition is a primary immunodeficiency disease, which means it is inherited and present at birth.
• [7] - Autoimmune disorders may also occur in patients with hyper IgM syndrome. These may include arthritis, low platelet counts (thrombocytopenia), anemia, hypothyroidism, and kidney disease.
• [8] - Hyper IgM syndrome is a rare primary immune deficiency disorder characterized by low or absent levels of serum IgG, IgA, IgE, and normal or increased levels of serum IgM.

Diagnostic Tests for Hyper-IgM Syndrome Type 2

Hyper-IgM syndrome type 2 (HIGM2) is a rare immunodeficiency characterized by normal or elevated serum IgM levels with absence of IgG, IgA, and IgE. The diagnosis of this condition involves several clinical and laboratory tests.

Clinical Criteria

The diagnosis of HIGM2 is suspected based on clinical criteria, including:

• Recurrent sinopulmonary infections
• Chronic diarrhea
• Lymphoid hyperplasia

These symptoms are often accompanied by a history of recurrent infections, particularly those affecting the respiratory tract and gastrointestinal system.

Laboratory Tests

The diagnosis of HIGM2 is confirmed through laboratory tests, including:

• Genetic Testing: Genetic testing is used to confirm the diagnosis of HIGM2. This involves analyzing the DNA sequence of the CD40 ligand gene (ICOS) or other genes associated with this condition.
• Immunoglobulin Levels: Measuring levels of immunoglobulins in the blood, including IgG, IgA, and IgE, can help confirm the diagnosis of HIGM2. Patients with this condition typically have low levels of these antibodies.

Other Diagnostic Methods

In addition to genetic testing and immunoglobulin level measurements, other diagnostic methods may be used to rule out other conditions or to confirm the diagnosis of HIGM2. These include:

• MRI: Magnetic resonance imaging (MRI) may be used to evaluate lymphoid hyperplasia.
• Chest Radiography: Chest X-rays may be performed to assess lung function and detect any abnormalities.

References

1. [2] - Hyper-IgM syndrome type 2 is a rare immunodeficiency characterized by normal or elevated serum IgM levels with absence of IgG, IgA, and IgE.
2. [5] - Diagnosis of hyper-IgM syndrome is suspected based on clinical criteria, including recurrent sinopulmonary infections, chronic diarrhea, and lymphoid hyperplasia.
3. [4] - Hyper IgM syndromes (HIGM) are characterized by decreased levels of immunoglobulin G (IgG) in the blood and normal or elevated levels of immunoglobulin M (IgM).
4. [9] - Testing for X-linked hyper IgM syndrome includes looking for the absence of CD40 ligand on activated T-cells.
5. [3] - Hyper IgM syndromes type 2 and 5 are usually confirmed through genetic testing.

Note: The numbers in square brackets refer to the search results provided in the context, which were used to generate this answer.

Treatment Options for Hyper-IgM Syndrome Type 2

Hyper-IgM syndrome type 2 is a rare primary immunodeficiency characterized by abnormal levels of antibodies, leading to recurrent infections and autoimmune complications. The treatment for this condition typically involves immune globulin replacement therapy.

• Immunoglobulin Replacement Therapy: This is the standard treatment for individuals with antibody deficiencies, including hyper-IgM syndrome type 2 [10]. Immunoglobulins (Ig) are given intravenously (IVIG) or subcutaneously (SCIG) to replace the missing antibodies and prevent infections.
• Prophylactic Antibiotic Therapy: In some cases, prophylactic antibiotic therapy may be necessary to prevent infections in individuals with hyper-IgM syndrome type 2 [8]. This is especially true for those who are unable to receive immunoglobulin replacement therapy.

It's worth noting that treatment options may vary depending on the individual case and the severity of the condition. In some cases, stem cell transplantation may be considered as a potential treatment option [9].

References:

• [1] Treatment of hyper-IgM syndrome usually includes immune globulin replacement therapy.
• [8] Hyper IgM syndromes are a group of rare primary immunodeficiencies that occur when people have abnormal levels of antibodies, called immunoglobulins.
• [10] Ig replacement therapy is the standard treatment for individuals with antibody deficiencies.

Immunodeficiency with Hyper-IgM Type 2 Differential Diagnosis

Hyper-IgM syndrome (HIGM) is a group of rare primary immunodeficiency disorders characterized by decreased levels of immunoglobulin G (IgG) and normal or elevated levels of immunoglobulin M (IgM). Immunodeficiency with hyper-IgM type 2 is one of the subtypes of HIGM. The differential diagnosis for this condition involves considering other causes of impaired class-switch recombination, which leads to elevated IgM levels.

Possible Causes:

• CD40 deficiency: This is a combined B cell and T cell immunodeficiency that can present with hyper-IgM syndrome (HIGM) type 2. CD40 deficiency impairs the interaction between B cells and T cells, leading to defective class-switch recombination [8].
• AID and UNG deficiency: These are B cell intrinsic immunodeficiencies that can also cause HIGM type 2. AID and UNG deficiencies impair the ability of B cells to switch from IgM to other classes of immunoglobulins [6].
• Other genetic defects: Various other genetic defects, such as those affecting the CD40 ligand (CD154) or the activation-induced cytidine deaminase (AICDA), can also lead to HIGM type 2.

Clinical Presentation:

The clinical presentation of immunodeficiency with hyper-IgM type 2 is similar to other subtypes of HIGM. Patients typically present with recurrent sinopulmonary infections, chronic diarrhea, and lymphoid organ enlargement [3].

Diagnostic Criteria:

Diagnosis of immunodeficiency with hyper-IgM type 2 is suspected based on clinical criteria, including elevated IgM levels, decreased IgG levels, and impaired class-switch recombination. Genetic testing can confirm the diagnosis by identifying mutations in the CD40 or AID/UNG genes [4].

References:

• [8] Elevated IgM levels are a hallmark of HIGM type 2.
• [6] AID and UNG deficiencies impair B cell function, leading to elevated IgM levels.
• [3] Recurrent sinopulmonary infections and chronic diarrhea are common clinical features of HIGM type 2.
• [4] Genetic testing can confirm the diagnosis by identifying mutations in the CD40 or AID/UNG genes.