Understanding Sinus Infections
How do I know when I have a sinus infection or chronic sinus infections?
- Why does the nose run?
- What causes it to run?
- What is the difference between a cold, allergies, sinus infection?
- What other structures or diseases can cause your nose to run?
- nasal masses
- reaction to pollution in the air
- The autonomic nervous system of the nose
By some accounts, sixty million people have a snotty nose in the United States of America. Most studies at least implicate 30 million. That’s almost one sixth of the population at the high end. The correct diagnosis of the snotty nose is an elusive character in today’s society because there are so many components of the environment that can trigger the nose to respond.
Nasal drainage and congestion can occur from a multitude of things:
- cat dander
- change of the weather
- and more!
Treatment for those conditions can be similar or different and they overlap. We doctors cannot always tell which one is causing the problem. Granted, we have many tests that may help us get an exact diagnosis, but when do you do them. Do all sixty million people get the same tests for every snotty nose? That would be extremely expensive, cumbersome, time consuming and likely unnecessary.
This means that determining what’s occurring when you have nasal signs and symptoms is complicated. Here is a short list of significant signs and symptoms of sinus infections:
- Nasal congestion
- Nasal drainage – both from the front and from the back (post-nasal drainage-
- Itchy nose
- Itchy eyes
- Watery eyes
- Teeth pain
- Facial pain
- over cheeks
- between the eyes
- over the forehead
- Facial tenderness
- Generalized Headaches
- Nose bleeds
- Swollen nasal tissues
Medically speaking, signs are physical exam parameters, meaning occurrences in the body you can see – drainage, swollen nasal lining, watery eyes, sneezing, tenderness, and bleeding in contrast to symptoms, which are the way you feel – itchy, congested, pain in your face and headaches. Often, but not always, signs of sinus infections can match up with symptoms such as nasal congestion correlating to swollen nasal tissues and the facial pain you feel matching up with facial tenderness when you push on your cheek.
To try to understand what is occurring in your nose when you have signs or symptoms, we really need to look at the mechanics of the nose. How the nose reacts to bad things – like pathogens and noxious stimuli. We learned about how the nose is constructed (the gross and microscopic anatomy) and the purpose and function of the nose in the discussion on what are sinuses and how do they work.
To understand how and why the nose reacts to the microscopic components of he air that get into the nose, we need to look at the microscopic reactions in the nose. This involves knowledge about basic immunology.
Understanding Basic Immunology in Regards to Nasal Passages
Your immune system is there to protect you from problems such as sinus infections, and other infections. It has a complex system of checks and balances to kill off bad things that get into your body, which scientists call pathogens. The word origin comes from the from Greek word pathos meaning suffering or emotion and gene, to give birth to. So pathogens give birth to suffering and death if not dealt with. But your body’s immune system incites an army when one of those invaders arrives on the scene into your body’s tissues.
The nose is just one way these pathogens, ie. bacteria, virus, fungi or protozoan, can get into your body. They can invade through a break in the skin, like a cut or abrasions, or invade through all the other holes in your body lined with mucous membranes – the mouth, eyes, or the genital area. Once inside the body, the immune system kicks in.
The basis for our ability to fight foreign invaders is for our body to recognize its own cells from the outside cells. In medicine this is called distinguishing between “self” and “non-self”. The cells that make up your body carry markers on the outside of the cell that mark it as “self.” Your own immune system will not attack these cells normally.
These “self” markers are called the major histocompatibility complexes (MHC) and have three main classes, MHC class I, on all cells and MHC II on specialized cells and MHC Class III on accessary cells of components of the immune system. They are compatibility proteins: to see if the cells are match to one another.
The immune system will accept or reject (attack) cells based on these complexes, which is why transplanted organs often get rejected if the MHC types are not matched up well. Just so you know, MHC matching is also call HLA, or Human Leukocyte Antigen matching. Leukocytes are another name for white blood cells, which are the cells that help control immunity. The word Leukocyte is composed of the Greek word leuko – meaning white and cyte meaning cell.
There are both white blood cells and red blood cells in your bloodstream. These names were given because when the blood was first being studied, it’s components were separated by spinning it quickly in a centrifuge. Three layers occur: a thin white layer of these immune protecting cells that occurred in a “buffy (frothy) coat” between a red layer (the red blood cells that contain hemoglobin that carry the oxygen through our body) and the plasma, which is a straw colored fluid of the leftover liquid and components of the blood, when the white and red blood cells are isolated.
Both the red and white blood cells come from our bone marrow. Bone marrow has stem cells. Stem cells are undifferentiated cells that have the potential to become any kind of cell they want. These are the cells doctors manipulate to create specific tissues and organs since they are like a blank canvass.
With respect to the immune system, these stem cells differentiate into two major precursors of the white blood cells: the Myeloid progenitor cell and the Lymphoid progenitor cell. These two main categories of our immune system affect the timing and the technique of the attack on the pathogens.
Even though these two groups overlap, generally speaking the Myeloid Progenitor cells develop into cells that respond early and nonspecific to infection.
The cells that develop from the Myeloid progenitor cells are the:
- Mast cells
- Red blood cells
The Myeloid Progenitor cells
Neutrophils are also called PMNs (polymorphonuclear leukocutes) because it looks like they have more than one nucleus as seen as the dark structures in the picture to the left. The nucleus is the brain of the cell where the DNA resides for the function of the cell.
Neutrophils consume bacteria upon contact and send out warning signals. Also part of the fast acting group are the monocytes that turn into macrophages and engulf bacteria and destroying them in your body’s tissues. Eosinophils and Basophils release granules to perform their functions, while basophils release histamine and other molecules that will stimuli your nasal response. Red blood cells (RBCs) and platelets are not really part of the immune system. RBCs carry hemoglobin and oxygen and platelets help out blood clot.
Each circle has a cell in the center of it that corresponds to a white blood cell. The smaller cells surrounding the white blood cell in the center are the red blood cells that carry hemoglobin and oxygen. 1,2: Eosinophils, 3, 4, 5: Neutrophils, 6, 7: Basophils
Lymphoid Progenitor cells
Lymphoid precursors develop into smaller white blood cells called T and B lymphocytes as well as natural killer cells and dendritic cells. Lymphocytes usually respond later in an infection. They form a more specific attack, and the T cells coordinate the attack. The dendritic cells, as well as the macrophages from the myelogenic line, engulf the bacteria or virus and then present these pathogens to the B cell, which turn into plasma cells and make specific antibodies to the bacteria or virus that has been processed. This takes more time, but also gives you a T cell line of lasting immunity called your “memory “ cells. Memory cells are primed and ready the next time that bacteria or virus gets into your body. They will kill it on the spot. These specific antibodies will be ready to help the attack by specifically binding to the unique bad bacteria.
This is how vaccines work. A little of the bacteria or virus is given to the body and this cascade of activity provides protective antibodies to ward off future attacks.
There are 5 types of antibodies, IgG, IgD, IgE, IgM and IgA
IgG accounts for most of our immunity in our body, IgA helps fight infection specifically in the nose and mouth and gastrointestinal tract, your “gut”, and IgE triggers the allergic response in your body. IgM and IgD play minor rolls. The allergic response is actually a malfunction of the immune system. Your body over-reacts and attacks particles, like pollen, grass, cat dander etc. that will not actually harm the body. Your body treats this allergen like it is a bacteria or virus, causing the same cascade of immunological particles to kill the particle and rid it from your body. This causes the same symptoms found in sinus infections, such as runny nose and nasal congestion.
So both myelogenous and lymphocytic cell lines have cells that kill on contact. Natural killer cells of the myelogenous cell line will interact with bacteria that it recognizes as “non-self” and will destroy it on the spot.
Cytotoxic T cells of the lymphoid cell line will also kill it on the spot, but it is more specific. Cytotoxic T-cells need a marker or receptor on their cell surface from a processed piece of the bacteria to recognize the pathogen. When that marker interacts with the bacteria, it recognizes it as bad and kills it.
Now that is the extremely simplified version, but generally how it works. All these groups of cells also work together to check and double check that what they are killing and producing antibodies to is right.
What Do Lymph Nodes Have To Do With Sinuses and Sinus Infections?
The lymph nodes in your body house most of the B cells that will eventually make our immunoglobulins, which are the specific attackers of each individual virus or bacteria. Lymph nodes occur all other the body, so the body is ready for an invasion anywhere when a break in the skin is occurs. The are connected to one another through the lymphatic system, which is the other major vascular system of tubes in the body, like the arteries and veins.
There are lymph nodes in the back of the nose and neck that work the same way.
You also have a ring of protective lymph tissue that surrounds the back of the nose and throat that work just like lymph nodes. These composed of 4 different but closely connected in in a ring. They include the adenoids (pharyngeal tonsils) that sit in the back of the nose as mentioned in chapter one, the tubal tonsils around the Eustachian tubes, the palatine tonsils and the lingual tonsils.
The palatine tonsils are the tonsils most people refer to as tonsils in the back of the throat. Lingual means tongue, like bilingual means the ability to speak two languages or tongues. The lingual tonsils sit on the back of the tongue and work like lymph nodes too, processing bacteria and viruses and making antibodies. All these tissues can become enlarged and /or infected and cause problems.
How The Nose Reacts to External Stimuli
So let’s get to the nose. Your nose reacts to the particles that get into it, whether that is a bacteria, virus, pollen, cat dander, dust, a particle of pollution or perfume or any other molecule. Initially, the bad particle encounters the very outside of the cell, which is the cilia on the top of the respiratory epithelium.
The cilia are in a gel aqueous (water) layer created by the goblet cells and sweep the offending particles to the back of the nose, as described in chapter one, where you swallow them and they are killed by your stomach acid.
If these cilia are impaired and they stop their sweeping motion, the secretions created by your nose stay in your nose and you don’t swallow them. This does not allow you to get rid of the pathogens, such as bacteria and viruses and you can get more infections, because they can penetrate into the deeper tissues of your nose because the hang around longer in your nose.
There are genetic medical conditions that will predispose to poor and impaired cilia function and nasal flow. The most widely encountered is Cystic Fibrosis. There is a genetic defect in secretory cells in which the cell membrane protein that performs that function is flawed.
So the cilia do not work well, which leads to problems in the nose and sinuses, respiratory tracts that lead to the lung and the gastrointestinal tract. Almost all children with Cystic fibrosis will have sinus symptoms similar to sinus infections, highlighting the important function of proper cilia motion in preventing disease.
Many noxious stimuli stop your cilia from beating as well, such as cigarette smoke or other toxins in the air. Noxious stimuli can also stimulate the nerves in your nose to react, as described in the discussion on the sinuses and how they work. These stimuli cause the release of chemical mediator’s that trigger sneezing, runny nose and congestion.
Similarly, cold air and barometric pressure changes can cause the nerves in your nose to react. Cold air is normally dry, because it chemically cannot hold as much water. Your nose likes to be moist to function, as described above, so it produces more mucus in cold drier air to try to maintain function. Your nose runs to produce more moisture in response to the cold air that is dry. Barometric pressure changes also stimulate the sensory nerves of the nose that can result in sneezing, runny nose, headaches and pain.
The junctions between the ciliated cells and goblet cells are normally tight. However if they are loosened, some pathogens or particles can get between the epithelial cells that line the nose and penetrate the basement membrane and get into the into layer underneath the epithelium called the lamina propria, which houses the blood vessels, like capillaries and sinusoids, as described in the discussion on how the sinuses work. That is also where many of the different types of immune cells reside.
If a bacteria or virus get down in these area, the immune system goes to work. It can engulf the pathogen and process it. It can recruit immune cells from other parts of the body by dilating the blood vessels present to allow them to bring in the rest of the army. When this occurs, the nose can get congested from the increase nasal swelling.
If the particle is an allergen, like a piece or pollen or cat dander, circulating IgE immunoglobulins previously produced from a prior expose can attach to immune cells and trigger the immune system to react. The immunoglobulins bind to Mast cells in the nose and signal them to release their chemical mediators, like histamine.
Histamine is a neurochemical mediator that can stimulate the sensory nerve in the nose, the trigeminal nerve, to cause tickling, sneezing, and rhinorrhea. It also can cause vasodilation of the small blood vessels of the nose and increase congestion. So the same symptoms that can occur from a bacteria or virus can occur with the allergic response, though the reaction or the immune system and nervous systems of the nose.
Additionally, the adenoids in the back of the nose will process the viruses and bacteria and will help you make antibodies to fight ailments such as sinus infections. This however, can cause the adenoids to swell, block the nose and cause congestion.
The Importance Of Adenoids Throughout Development
The adenoids begin their protective action making antibodies at birth and continue as the child grows. The adenoids often enlarge as the child gets older in response to their function. Enlargement can cause obstruction in the back of the nose, often by two to three years of age but occasionally as young as one year of age or earlier. The adenoids usually peak in size by five to seven years of age (when the child’s immune system is almost as mature as an adults) and then shrink by preteen or teenage years, so they may not be the culprit of nasal obstruction in a child older than eight to ten years of age. However, this is the general trend. There are always exceptions, so adenoid enlargement causing nasal congestion and nasal symptoms could occur at any age. These changes could lead to an increased or decreased risk of sinus infections.
And even if the adenoids do not get big enough to block the flow of mucus in the nose, they could still harbor bacteria and act as a nidus of infection. Bacteria can overwhelm the adenoids and take over the tissue. The bacteria can use the adenoid tissue as a fort and a basis of operations.
There the bacteria can grow and send out troops to infect the sinuses causing the nasal allergy symptoms. (In Medscape/Emedicine, one of the most trusted internet sources of medical information, there is a chapter on adenoidectomy written by me that describes this all in detail)
How To Handle A Runny Nose
So how do you tell what is occurring when you have a runny nose? How do you tell if there is an infection, or allergies, or pollution or just change in the weather? Are sinus infections always the answer?
In order to diagnose sinus infections, first we can evaluate the signs and symptoms you have. While many overlap, certain ones, like facial pain, long term symptoms lasting 10 to 14 day with thick yellow green mucus, fever, bad breath and absence of sneezing means you probably have a sinus infection and should consider treatment.
Sometimes that treatment may require nasal saline irrigation, but you should do something to get rid of the bacteria that is probably present and causing your symptoms.
What is Rhinitis?
Doctors largely name the runny nose, or rhinitis, under allergic rhinitis, which accounts for one half to two thirds of the 60 million people affected and non-allergic rhinitis, which is a combination of everything else.
Other causes of rhinitis include:
- Obstructing lesions like the adenoids
- Rhinitis from noxious stimuli
- Cigarette smoke
- Chemical irritants
- Rhinitis from air quality
- Inadequate moisture
The term rhinosinusitis is often used when there are common symptoms of sinus infections, like fever and yellow or green drainage, present with some for of the allergic and non-allergic rhinitis.
When doctors try to figure out which one of these rhinitis is occurring, we also have a battery of tests. We can order blood tests to see if sinus infections are suspected. If the white blood cells are elevated in your body, your body is reacting to a foreign invader.
In allergies, even though your immune system is reacting, it is reacting locally, so the white blood cells do not usually become elevated in your bloodstream. During an infection with a pathogen, like a virus or bacteria, they do.
And the components of the white blood cells will be elevated with different types of infections. The lymphocytes get more elevated with a viral infection. The neutrophils become more elevated in a bacterial infection. The eosinophils are more elevated in a parasitic infection. Occasionally your eosinophils can be elevated in allergy, but your entire total count may not be.
Doctors can perform nasal cultures to attempt to delineate if bacteria is present and what type, but a negative culture does not always mean there is no infection. It may mean the specimen was inadequate or processed wrong. We can even culture the sinuses by sticking a needle into the maxillary sinus under the cheek though the nasal cavity. (ouch!)
We can perform a nasal smear by looking at the secretions in your nose under a microscope and see what components are present. If there is a lot of eosinophils, the nasal symptoms cold be related to allergy. Often, however, when allergies affect the nose, the sinuses become blocked which can lead to sinus infections. So both allergies and infection can occur simultaneously. In fact, that’s often the case. The are multiple problems occurring at the same time, making the diagnosis even harder.
Allergy testing is also an option, both with blood tests and skin tests. We can test from hundreds of allergens, including food, chemical, insects, animals, stress, grasses, weeds, dust, fungus and so on. The skin tests can be divided into the prick test and the intradermal tests. The skin tests are generally more sensitive.
We can also perform x-rays, both regular x-rays, CT scans and MRIs. Regular x-rays in children can be wrong over 40% of the time and cause radiation, so we do not use these very often. CT scans are accurate for the presence of secretions, but do not tell you if the secretions are infected. And CT scans as well are accompanied by radiation exposure, which, if occurs over and over again, has been recently shown to potentially increase the risk of future cancers.
Over ten years ago, it was not uncommon for children to get several x-rays in the course of their sinus infections or disease. We are more judicious now. When surgery is indicated or when the diagnosis is unsure, CT scans are helpful and should be obtained. MRIs are rarely used specifically for sinus disease since they are expense and unnecessary for the diagnosis. However, if a nasal sinus tumor is suspected, they are indicated. MRIs however have n radiation risk.
If You Suffer From Sinus Infections, Consult With A Doctor
Other diseases like gastroesophageal reflux, autoimmune disease and specific syndromes can predispose to sinus disease and there are special tests for all of them. There are special tests for the immune system.
So when do you order them? In every patient? Every time they see you?
With so many possibilities, and so many new patients everyday, both doctors and patients alike have to put together pieces of a puzzle to diagnose sinus infections and other sinus problems. It’s important to pay attention to how the disease presents, which means asking the important questions:
- What are the signs and symptoms of the patient ?
- Is the patient male or female?
- How old is the patient?
- Where does the patient live?
- What are the patient’s living conditions like?
- Who does the patient interact with?
- What is the patient’s genetic history?
We use all of this information to construct a diagnosis to determine what tests to order or if to determine treatment. In order to make sure you receive the right tests, be sure to communicate with your doctor about any and all symptoms that give you reason for concern. If you suffer from sinus infections in Frisco, TX, call our office today at 214-494-4150 and schedule your appointment with Dr. John McClay!