Potential for Complications of H1N1 and Lupus Patients
Systemic lupus erythematosus (SLE, lupus) is an autoimmune disease. Autoimmunity is when a patient’s immune system mounts a response to antigens on their own cells and tissues. In the case of SLE the immune response is directed primarily against DNA contained within the nucleus of the cells. As well anti-nuclear antibodies (a-dsDNA), SLE patients can also produce antibodies to phospholipids in the blood known as antiphospholipid (aPL) antibodies.
The condition is characterized by periods of inactivity and flare ups and at its most serious can involve kidney damage. In order to control the disease, many patients are prescribed immunosuppressive drugs.
SLE patients have a greater risk of infection than healthy individuals for two main reasons:
Defects in the immune system, which reduces the response to infectious organisms.
The immunosuppressive drug treatment given to control the dangerous autoimmunity, can depress the protective immune response against infection.
Influenza related morbidity and mortality are higher in immunocompromised patients. Laboratory studies have shown that the level of immune response to influenza is lower in SLE patients compared to healthy people. These responses can be even further decreased during periods when their SLE is active.
The recent outbreaks of H1N1, a strain of influenza A, raises concern for SLE sufferers. Vaccination against H1N1 is recommended. However, there have been doubts as to whether this is safe and effective in SLE patients.
Safety of Influenza Vaccination in SLE Patients:
There is a general concern in all autoimmune conditions that vaccination can cause a problematic stimulation of the immune system, which exacerbates the autoimmune disease. Reports in the medical literature on safety of influenza vaccination in SLE patients generally support vaccination of these patients. One study in 2006 reported a rise in aPL and a-dsDNA antibodies in some SLE patients after influenza vaccination, but no significant worsening of SLE disease.
There is potential for complications of H1N1 and lupus patients, but at present vaccination is considered safe. This is particularly the case in patients with stable, inactive disease. A recent study comparing vaccination with Influvac (which has activity against A/H1N1) in both SLE and healthy people, showed no increase in SLE symptoms. Lupus patients did however show a greater incidence of vaccine induced side-effects than the healthy subjects. These side-effects included redness and itching at the vaccination site, but these were generally mild and short-lived.
Effectiveness of Influenza Vaccination in SLE Patients:
Several studies have shown that vaccination against influenza in SLE patients generates an immune response (antibody and T cells), but this is notably lower than in healthy people. This is likely to be due to the effects of immunosuppressive drug treatment taken by SLE patients. For example, use of the drug azathioprine has been clearly shown to decrease the effectiveness of influenza vaccination. However, the vaccine induced response may still be sufficient to provide protection against H1N1 infection.
“Influenza Vaccination and the Production of Anti-phospholipid Antibodies in Patients with Systemic Lupus Erythematosus.” P.Tarjan et al. Scandinavian Journal of Rheumatology, 2006, Vol 35, P241-243.
“Studies of Cell-Mediated Immune Responses to Influenza Vaccination in Systemic Lupus Erythematosus,” A.Holvast et al. Arthritis and Rheumatism, 2009, Vol. 60(8) P2438-2447.
“Safety and Efficacy of Influenza Vaccination in Systemic Lupus Erythematosus Patients with Quiescent Disease,” A. Holvast et al. Annals of Rheumatic Diseases, 2006, Vol 65(7), P913-8