Medical Care
Common variable immunodeficiency (CVID) patients were divided into four distinct clusters correlating to perceived health, a potentially important factor in providing care. [45]
The mainstay of treatment for common variable immunodeficiency (CVID) is Ig replacement therapy. Although expensive, Ig replacement therapy stops the cycle of recurrent infections. See the image below.
Ig may be administered intravenously or subcutaneously. Solutions of 3-12% intravenous immunoglobulin (IVIG) can be used on a regular basis to maintain a trough level of 400-500 mg/dL in adults. A dose of 400-600 mg/kg every 2-4 weeks is usually required. In patients with structural lung damage, a trough level of 700-800 mg/dL is required.
A solution of 16% subcutaneous injection of IV immunoglobulin (SCIG) is also an effective treatment in patients with poor intravenous access. As expected, the volume required to achieve adequate trough levels is much higher with SCIG than with IVIG. A dose of 160 mg/kg/wk is comparable to an IVIG dose of 400 mg/kg/mo.
Adverse reactions to Ig administration must be monitored during therapy. The most common reactions include backache, nausea, vomiting, chills, low-grade fever, myalgias, and fatigue. Adverse effects occur within 30 minutes of the infusion and usually last for several hours. Slowing the rate of infusion or interrupting the infusion for a few minutes greatly helps in preventing symptoms. The effects can be treated with antipyretics, diphenhydramine, and/or corticosteroids. Although anaphylactic reactions to IVIG are uncommon, patients with IgA deficiency have an increased risk for these effects. Long-term intravenous access is not recommended because it can increase the risk of infection.
The transmission of infectious agents during infusion has caused problems in the past. Although no cases of HIV infection have been linked to Ig therapy, the transmission of hepatitis C virus has been reported. Current methods of viral inactivation help prevent transmission. These methods include treatment with organic solvents and detergents, pasteurization, and storage at a low pH. In the United States, Ig products are derived from pooled human plasma, which undergoes a manufacturing process that includes cold ethanol fractionation and viral inactivation steps.
In most patients, CVID responds well to Ig therapy. The recurrence of infections, arthritic symptoms, and the severity and/or incidence of the autoimmune disease are reduced. Gastrointestinal disease shows little improvement with IVIG. In some patients with severe autoimmune disease, the concurrent use of steroids or other immunosuppressive drugs may be needed.
Cyclosporin A has been successfully used in patients with CVID and lymphoid interstitial pneumonitis. The administration of anti-CD20 monoclonal antibody has been used to treat autoimmune thrombocytopenia and neutropenia. Studies are underway to evaluate the efficacy of IL-2 administration in conjunction with polyethylene glycol. Results of early in vitro studies show an increase in Ig production by B lymphocytes.
Antimicrobial therapy should be initiated at the first sign of infection. A narrow spectrum of drugs should be used when culture and sensitivity results are available. The prophylactic use of antibiotics should be avoided because of an increased risk of infection with fungi or other resistant organisms.
Specific therapy is often necessary to target the organ system involved. For instance, patients with chronic lung disease often develop airway obstructive disease that requires treatment with inhaled corticosteroids and other asthma medications.
Patients with CVID at risk of coronavirus disease 2019 (COVID-19) represent a challenge. [46] Use of convalescent plasma and intravenous immunoglobin may be considered, with efficacy not yet determined. A small sampling of ten CVID patients in New York City developed COVID-19, only one of whom was hospitalized and all recovered. [47]
In pregnant patients with CVID and lung disease, the pulmonary deficit is often exacerbated in the third trimester. If the mother receives adequate IVIG replacement therapy during pregnancy, her neonate (with CVID) has IgG levels in the reference range because the antibody is actively transported across the placenta.
Patients and their families may benefit from a periodical health-related quality-of-life assessment, highlighting the value of psychological support. [48]
Inpatient care may be necessary, depending on the severity of the clinical manifestations secondary to CVID.
Surgical Care
Surgery is required to treat the complications of common variable immunodeficiency (CVID). Chronic sinusitis may require endoscopic sinus surgery. Severe autoimmune thrombocytopenia or hemolytic anemia can be treated with splenectomy. Biopsy should be considered to exclude infection or malignancy in enlarging lymph nodes.
Consultations
A specialist should be consulted whenever necessary.
Prevention
Because at least some CVID patients can produce protective antibody titers, one should consider the inclusion of polysaccharide vaccine in an immunization program for them. [49] Most CVID patients would benefit from seasonal influenza vaccination. [50]
Long-Term Monitoring
The mainstay of outpatient care is the prevention of secondary medical conditions. IVIG should be administered every 2-4 weeks to keep the level of serum antibodies in the reference range.
Although long-term intravenous access is often required for IVIG therapy, it is not recommended. The use of a plastic cannula should be avoided because it can increase the risk of venous sclerosis. Butterfly needles should be used in their place. Alternatives to implantable venous access devices should be sought, although such devices have been used for long periods without problems.
Patients should see their physicians annually, unless they develop associated infections, which warrant immediate treatment. Physicians should obtain a thorough history and perform a thorough physical examination. Patients should be evaluated for associated conditions such infection, autoimmune disease, and malignancy.
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Intravenous immunoglobulin infusion. Courtesy of Wikimedia Commons (Steve Brew, own work).