With the popularization of the internet and education, people have started to realize the importance of the immune system, acknowledging it as our guardian. But what happens if the immune system malfunctions? Let's learn about Idiopathic Late-Onset Hypogammaglobulinemia. What causes Idiopathic Late-Onset Hypogammaglobulinemia?
(1) Etiology: The cause is unknown, with no apparent genetic predisposition, although there are reports of several members of the same family being affected by this disease.
(2) Pathogenesis: The pathogenesis is still unclear. Molecular genetic studies suggest that this disease and IgA deficiency may be associated with the same susceptibility gene, namely the complement 4A gene (C4A) located in the MHC class III region on chromosome 6.
What are the manifestations of Idiopathic Late-Onset Hypogammaglobulinemia and how is it diagnosed? Most cases occur in individuals aged 10 to 30 years, primarily affecting adults. 45% of patients are diagnosed before age 21, with an equal distribution between males and females. There is often a history of autoimmune diseases or immunoglobulin abnormalities in the family. Clinically, patients are highly susceptible to pyogenic bacteria, with recurrent infections by bacteria such as Haemophilus influenzae, Streptococcus pneumoniae, Streptococcus hemolyticus, and Staphylococcus aureus. They often suffer from recurrent sinusitis, bronchitis, otitis media, and pneumonia. Chronic progressive bronchiectasis may develop over time. Sprue-like syndrome is also common, with most patients experiencing diarrhea, steatorrhea, and sometimes protein-losing enteropathy and malabsorption. Some patients may improve with a gluten-free diet or by avoiding milk. Patients are also prone to autoimmune diseases (about 22%), such as SLE, vitiligo, thrombocytopenic purpura, pernicious anemia, and autoimmune hemolytic anemia. Some authors have reported that 90% of patients have diarrhea, often accompanied by steatorrhea, hypochlorhydria, and giardiasis; 28% have bronchiectasis and splenomegaly; 12% have thyroid disease; and 6% have keratoconjunctivitis sicca and pernicious anemia. The incidence of malignancies of the lymphatic and reticular system is also high, such as gastric cancer, colorectal cancer, and rectal lymphoma, especially in those aged 50 to 60 years. Another characteristic is the frequent occurrence of granulomas of unknown cause, without caseous necrosis, and no microorganisms are found in the lesions. They often affect the skin, lungs, spleen, and liver, and corticosteroid therapy is effective. Granulomas often occur for unknown reasons, without caseous necrosis, and microorganisms are not found in the lesions. They often affect the skin, lungs, spleen, and liver, and corticosteroid therapy is effective. There is almost no antibody response after vaccination, and delayed-type skin test reactions are weak. Histopathological examination of lymph nodes reveals a lack of plasma cells and obvious hyperplasia of lymph follicles but with a lack of vitality. Lamblia is often found in duodenal biopsy, and improvement can be seen with metronidazole treatment.
Treatment of Idiopathic Late-Onset Hypogammaglobulinemia
(1) Treatment
1. General Therapy
(1) Enhance care and nutrition: to improve the patient's resistance and immunity.
(2) Prevent infection: Isolation measures should be taken to minimize contact with pathogens.
2. Anti-infective Therapy
Due to low humoral immunity, the body cannot kill infected pathogens. In case of infection, broad-spectrum antibiotics should be selected. Bacteriostatic antibiotics cannot prevent the spread of pathogens, so bactericidal antibiotics should also be used for treatment.
3. Immune Substitute Therapy
(1) Human serum γ-globulin: Mainly using γ-globulin for replacement or compensatory therapy can allow children to survive normally, even into adulthood. The dose is 100-200 mg/kg each time, intramuscularly, once a month. A serum immunoglobulin concentration of 3.0 g/L is helpful for controlling infections. Since the half-life of γ-globulin is 0.5 to 1 month, subsequent doses of 100 mg/kg, intramuscularly, once a month, can maintain its serum
