Infectious Processes and Lupus

Infections from pathogens like bacteria, viruses, and fungi are a major issue for people with lupus. They may even serve as a catalyst for symptoms of autoimmunity.

Systemic lupus erythematosus, or SLE, is a chronic autoimmune disease with a wide range of symptoms — most of which are caused by inflammation throughout the body. Inflammation is a normal part of the autoimmune response, helping the body to protect itself. However, autoimmunity occurs when the same inflammation processes misidentify and attack healthy tissues.

Root causes for autoimmunity include genetic predisposition and environmental triggers. Anecdotes and research are beginning to suggest that a person may develop symptoms of autoimmunity after an infection. In people who have vulnerabilities in their immune defenses, even often otherwise innocuous infections can potentially break down the body’s ability to censor and destroy antibodies that target the body’s own cells.

Aside from understanding the causes of disease, infections provide plenty of concerns for Lupus Warriors. People with lupus are more vulnerable to infections and can become sicker, even requiring hospitalizations. In fact, infections are a leading cause of morbidity and mortality in patients with lupus. This is caused by two factors:

• immune system inefficiencies caused by lupus;
• medications, like immunosuppressants, which reduce the activity of the immune system down lupus symptoms, people with lupus are vulnerable and can become sicker than usual

Let’s look more closely at the links between infections and autoimmunity.

Infections and Lupus

Genetics, age, and the environment are thought to be the main factors that lead to the development of lupus. However, when people have these vulnerabilities, infections can trigger the onset of lupus.

Typically, the body has ways to prevent the immune system from attacking the body’s own tissues. For example, the immune system has a process for eliminating autoantibodies (immune system cells that accidentally target the body’s own cells). However, some pathogens (infection-causing agents) can mimic the body’s own identifying proteins. This helps the pathogens avoid detection, like camouflage. Eventually, the immune system finds a way past this disguise, but sometimes it does it in the wrong way. By creating antibodies for the camouflage, the body’s identifying proteins, instead of something that identifies the pathogen itself.

Targeting the body’s identifying proteins makes it more likely for the immune system to damage the tissues and organs of the body, especially in times of high immune system activity, such as during an infection. This can lead to autoimmune disease.

You can read more about the immune system and lupus here.

But, the relationship between pathogens and autoimmune disease can be complicated.

The Hygiene Hypothesis is the idea that infection by certain bacteria or parasites might actually be protective. This claims that autoimmune diseases and allergies result from a lack of contact in childhood with harmless dirt due to cleaning. It’s not confirmed, and the risks of infection and illness outweigh any benefits.

Interestingly, infection with malaria and harmless bacteria had shown some beneficial effects in mice with lupus. And of course the gut microbiome is important to consider people with lupus.

Infection-caused inflammatory disorders are a potential starting point to understand lupus, and might also cause chronic fatigue syndrome, among other disorders. They are also important for SLE treatment and detection. Since infections can also mimic SLE symptoms (and vice versa) making it difficult to diagnose infections when they arise.

The general consensus is that the infection doesn’t cause SLE or autoimmune disease.

Instead, the autoimmune disorder was already there, but either dormant or not noticed. The infection activates a flaw or vulnerability caused either by a person’s genetics or by damage from the environment. Often, this damage or vulnerability has been present for a while, and might have been building up over time. However, the infection, and the inflammation and immune response that it causes, can push the body over the edge into a recognizable onset of disease. Certain diseases have a stronger link to autoimmune diseases than others.

Many pathogens can cause an abnormal immune response including:

• viruses
• bacteria
• parasites

Certain pathogens seem more likely to lead to an emergence of lupus symptoms and disease activity. Researchers have noted that, in people with SLE, the immune response towards several viruses is weaker. These viruses include include: Epstein–Barr virus, parvovirus B19, cytomegalovirus and human immunodeficiency virus type 1. There are also are some bacterial infections that may be involved along with Hepatitis C.

Treating Infection and Lupus

Infections can be treated with various medications, depending on the infection. However, it is vital to distinguish between a lupus flare and an acute infection. Lupus medications can create vulnerabilities to infection, and some medications can interact with each other in unpredictable ways.

In either case, it is important to treat these infections quickly, before they cause serious harm.