Tag Archives: lupus

What the heck is a connective tissue disease?

This week, I was called to evaluate a young man with several aneurysms (ballooning of his blood vessels) and a dilated (widened) aorta.  The medical team thought he had a “connective tissue disease” because a family member also had a connective tissue disease–she had lupus.  Unfortunately, doctors can mean very different things when they talk about a “connective tissue disease;” this is a common source of confusion for doctors and patients alike.  After reading this post, I hope you’ll be able understand the difference.

Connective tissue is the “stuff” that holds your body together.  That is, the bones, ligaments, tendons, cartilage, fat, and “glue” that keeps all your organs in place.  Two very different types of diseases can affect these tissues–you can have problems in MAKING the connective tissues, or these tissues can be ATTACKED by the body’s own immune system.

In the first type of “connective tissue disease,” the body is unable to produce strong connective tissues.  It’s like trying to build a house with weak materials.   If the materials are weak, the house is likely to develop cracks on the walls, holes in the roof, and the whole structure may fall down.  There are many genetic (heritable) diseases that prevent the body from making high-quality building blocks.  Marfan syndrome, for example, is a disease where the body is unable to make high-quality fibrillin (a protein present in many types of connective tissues).  This causes weakness of various parts of the body including the eye (causing lens dislocation), the aorta (causing dilation and potential to rupture), and lungs (causing pneumothorax, or collapse of a lung).   Ehlers-Danlos is another group of diseases where patients have difficulties making collagen, another protein necessary for high-quality connective tissues.  In this disease, patients have loose joints that often dislocate, fragile skin that is unusually “stretchy,” and have difficulties healing after injuries.  In the most severe cases of Ehlers-Danlos, the blood vessels are also weak, making them prone to breaking and causing internal bleeding.  Because these types of connective tissue diseases are genetic (hereditary), medical geneticists are the experts in this field.

The second type of “connective tissue disease” does not involve problems in making the building blocks of the body.  In fact, the body is able to make all of the connective tissues without a problem.  However, once these tissues are made, they are attacked by the body’s own immune system (and thus they are autoimmune diseases).  The body’s own immune cells (white blood cells) are tricked into thinking that the connective tissue is abnormal, and thus they  attacking those tissues.  In a sense, the body can build a house with high-quality materials, but the house is invaded by wild animals that can damage the structure of the house.  In Sjogren syndrome, for example, the glands that make tears and saliva are attacked.  In scleroderma, the skin and internal organs are attacked.  In lupus, many organs can be attacked, including the kidneys, skin, and lung.  To date, we have very little idea what causes these diseases.  Because these types of diseases are autoimmune and often involve inflammation, rheumatologists are the experts in these types of illnesses.

Don’t you think we should change the name that we use to refer to these two very different types of diseases?  What names do you propose?

After reading this post, what kind of disease do you think my patient had? Genetic or autoimmune?

What the heck is rheumatology?

When I meet someone for the first time and tell them that I’m a rheumatologist,  I usually get blank stares, as if I had spoken to them in a foreign language.  It doesn’t matter if they are a medical student, family member,  or even an immigration officer.  It doesn’t matter if they have a PhD or they are a high school dropout.  I even see patients in my rheumatology clinic who have no idea what rheumatology is, nor how I’m supposed to help them.

I can’t blame them.  Rheumatology is a weird field.  Just look at the origin of the word “rheumatology.”  The prefix “rheuma,” meaning “to flow,” was first used by a Greek physician 2000 years ago,  referring to the phlegm that flows from the nose when a person is ill.   But rheumatology, as it is practiced today, has nothing to do with phlegm (talk about false advertising!).  Cardiologists don’t have this identity problem because they, of course, manage the heart.   Dermatologists treat your skin.  Proctologists…well, you get the picture.  

A quick web search about rheumatology is not fruitful either.  Rheumatology is defined as: “the medical specialty that manages rheumatic diseases.”  My rheumatology textbook doesn’t even try to define what field is all about.

In addition, we’re not a popular specialty.  I don’t know of one famous rheumatologist.  We’re not usually in the news.  We’re not  the heroes in any movie.  In fact, I don’t  think I’ve ever seen a TV character who is a rheumatologist (even though there is at least one paleontologist on TV!).   The TV character that most closely approximates what a rheumatologist does is my hero Dr. House (no relation, unfortunately) on the TV show House, MD.  He is actually board certified in nephrology and infectious diseases, but he gets consulted on very complicated cases, much like rheumatologists often do.  However, he’d make a lousy rheumatologist because, according to him, “it’s never lupus!”

As I see it, rheumatology is the study of inflammation (swelling, redness, warmth, and pain) occurring in the structures that hold up the body, such as the bones, muscles, and joints.  Arthritis, or inflammation of the joints, is the most common disease that we see, both in children and adults (kids get arthritis too!).  Arthritis comes in a variety of flavors, including juvenile, rheumatic, psoriatic, gouty, osteoarthritis, etc..

We also take care of complex diseases such as systemic lupus erythematosus, systemic sclerosis,  and dermatomyositis, in which the immune system attacks various different organs.  Vasculitis, or inflammation within a blood vessel, is another disease which we treat.  Other strange illnesses (with even stranger names) such as Kawasaki disease, Sjögren syndrome, and relapsing polychondritis are all within the field of rheumatology.

Most of the above-mentioned diseases are considered autoimmune, in which the immune system loses the ability to recognize self from non-self.  When a cell of the immune system passes through the kidney, it should be able to recognize it and say: “Hello! You are my kidney, I will protect you against infections!” However, in autoimmune diseases, the immune cell gets confused and says: “Whoa! What is this bean-shaped organ doing here? You look foreign, I will fight you to the death!”   As a result, the immune cell begins a process of inflammation that causes organ damage.  Many different organs can be affected in autoimmune diseases, and the name of the disease depends on which organ is affected.

At the other end of the rheumatology spectrum are autoinflammatory diseases (my favorite!).  These diseases occur when the machine that produces inflammation goes awry.   Immune cells are tightly regulated to produce inflammation only when needed (such as in response to a microbe or to damaged tissue).  However, in most autoinflammatory diseases, there is a mutation within the inflammation machine that causes it to produce inflammation at inappropriate times.  The immune cell in autoinflammatory diseases says: “Darn, I’m leaking inflammatory fluid yet again!”  Thus, the patient develops episodes of fevers, rashes, and joint pain without any other explanation.

As you can see, rheumatologists manage a wide variety of illnesses that affect many different organs.  Most of these diseases do not have clear causes, which makes rheumatology a fascinating field to study.  At least until a smart marketing team comes up with a better name for our specialty (I vote for “inflammatology!”), you won’t have to look at me weird when I tell you what I do for a living.