Adenomyosis Uteri is a glandular derangement of the muscle of the uterus. It's a common cause of uterine symptoms after the age of 30. Rather than just throw out that clinical definition without further explanation, I think it makes sense to cover a few basics.
The first thing to know about adenomyosis is how to pronounce it. The introductory "a" is short, pronounced like the "a" in "apple." The "den" is pronounced like a lion's den or the informal room in your home. In other words, the "e" is short. The rest of the word is pronounced just as it appears, with accents on the "a" and the second "o".
The second thing to know about adenomyosis is what it is. The medical term adenomyosis uteri is succinct and descriptive if you remember your high school Latin (ok, I may be dating myself here). The "adeno-" part of the word is a medical term that indicates something that has glands. The "myo" part of the word refers to muscle. The "-osis" is a generic suffix that implies a derangement (irregularity) of the organ or tissue that precedes this suffix. In other words, adenomyosis is an irregularity of glands in muscle tissue. In Latin, "uteri" is the possessive case of the word for uterus. Put all these thoughts together and you get Adenomyosis Uteri: a glandular derangement of the muscle of the uterus.
Anatomy of the uterus
The uterus is a structurally simple organ that has basically only two types of tissue: the endometrium and the myometrium.
1. The endometrium
This is the interior lining of the uterus which produces the menstrual flow and into which the fertilized egg implants in early pregnancy. The most superficial layers of the endometrium slough and shed each month with the menstrual flow, then regenerate from the deeper layers. The endometrium has glands within its tissue structure.
2. The myometrium
This is the relatively thick muscle wall which gives the uterus its pear shape. Muscular activity is important for expelling a baby from the uterus during delivery. This muscular activity can also be painfully obvious when the uterus is expelling large clots that can occur during a heavy menstrual flow.
Normally, these two tissues don't mix. In the condition adenomyosis, the muscle wall of the uterus is invaded by tissue from the lining. There are two theories to explain how the muscle comes to be invaded by the endometrial lining. It is thought that many cases are explained by direct invasion of the endometrium into the immediately adjacent myometrium. This theory is supported by the fact that during microscopic examination of adenomyosis in the lab, it is possible in some cases to follow the endometrium in a continuous non-broken layer from its normal location on the lining and observe it invading the muscle.
A second possibility is that the muscle tissue for some reason may undergo change into tissue which resembles the endometrial lining. The change of one type of tissue into another is called metaplasia. Metaplasia is supported by the fact that some "islands" of adenomyosis can exist within the muscle wall of the uterus with no apparent direct contact with the uterine lining.
We don't know why some women develop adenomyosis, but it becomes more common as women get older. It is most commonly diagnosed in the 30-45 year old age group. Some authors have rendered the opinion that this disease is related to pregnancy, with the possibility that the stresses of labor and delivery and subsequent uterine repair allow the lining cells to invade the muscle wall. However, adenomyosis can also occur in women who have never been pregnant.
Uterine pain and bleeding are the main symptoms of adenomyosis. The symptoms most commonly begin after the age of 25, but adenomyosis can occur in younger women. Pain is no surprise when you consider that the hormonally active glands which invade the muscle very likely secrete something which irritates the muscle. You could imagine how your biceps (upper arm) muscle might hurt if you had little glandular factories within it that were manufacturing lemon juice or some other irritative fluid.
Uterine pain can come in several forms. The most obvious would be uterine cramping with the menstrual flow, but some women can have this cramping begin days or even weeks before the flow. A few unlucky women suffering from adenomyosis may have uterine cramping all month long, with particular aggravation during the menstrual flow. It's as if the uterus is being irritated like it has a hot coal within it.
This more chronic irritation can lead to other types of pain. If the uterus hurts like a sprained ankle, then anything that physically hits the uterus may be painful. The uterus lies directly at the end of the vagina and is hit directly during sexual intercourse. If the uterus is irritated by adenomyosis, painful intercourse can result, particularly around the time of the menstrual flow.
To its rear, the uterus can also be hit by stool passing by in the rectum, and this can produce pain with bowel movements.
Expansion and contraction of the urinary bladder can also affect the uterus, and some patients may have pain during urination as a result.
In a rare patient, the "hot coal" analogy can be more accurate than you might expect. I have seen occasional cases of diarrhea, bloating and nausea clear up after removal of a uterus involved by adenomyosis.
Adenomyosis is not thought to reduce fertility, although the real effect on fertility is virtually impossible to know since it is so difficult to diagnose the disease in women who have a uterus. Adenomyosis used to be called "endometriosis interna", since it can look somewhat like endometriosis under the microscope but occurs within the muscle wall of the uterus, not on pelvic surfaces as does endometriosis.
Adenomyosis does not seem to occur more commonly in patients with endometriosis. However, both are frequent causes of pain so some women may have pain early in life from endometriosis and later in life from adenomyosis.
The personal medical history is obviously important in the diagnosis of any medical condition. Unfortunately the symptoms of adenomyosis (pain with the menstrual flow, painful sex, painful bowel movements with the flow, etc.) can closely resemble the primary symptoms of endometriosis. Careful questioning and listening can help to begin to distinguish the two.
Occasionally a patient will describe this pain as being like the uterine cramping she experienced during labor and delivery. This may be helpful in pointing a finger at the uterus rather than at endometriosis.
Many patients will point at the center of the pubic bone as the source of their pain and may be convinced that they can distinguish the uterus as the source of the pain. The doctor should listen to these patients and believe them.
While patients with endometriosis sometimes describe a sense of cramping from their disease, they seldom seem to relate this cramping to a definite uterine source.
Another helpful part of the history is that the pain of adenomyosis seems to begin later in life than does the pain of endometriosis. Patients with endometriosis describe pain beginning virtually with the onset of the menstrual flows, and additional layers of pain can be added into the mid-20's. Patients with adenomyosis seem to begin experiencing pain from this disease in the early 30's.
The uterus has physical attachments to the lower back via the uterosacral ligaments, to the upper thighs through the round ligaments, and to the umbilical area through the urachus and obliterated umbilical arteries that come off the uterine arteries. Therefore many patients with a uterine source of pain may describe pain radiating to these areas. This may help differentiate uterine pain from endometriosis pain.
Endometriosis pain can radiate to the lower back in some patients with invasive disease of the uterosacral ligaments, but rarely radiates pain to the upper legs or belly button.
The physical exam may be helpful since the uterus may be tender with adenomyosis, while the rear of the pelvis may be tender with endometriosis. Unfortunately, not all pelvic exams are done with a view toward palpation of the uterus individually or the rear of the pelvis individually to see if either or both areas are painful. Many doctors are mainly interested in the size, shape and position of the uterus and the size of the ovaries, not whether there are specific points of tenderness.
There is no blood test for adenomyosis, and it infrequently shows up on ultrasound, CT or MRI scans since the density of the tissue may not differ sufficiently from the surrounding uterine muscle wall. Occasionally the uterus may be described as slightly enlarged in a symmetrical fashion, with a fuzzy shadowy pattern seen in the muscle wall.
Some forms of adenomyosis can resemble nodules or clumps of disease which can show up on scans like small marbles within the muscle wall, although some nodular adenomyosis can reach the size of a ping pong ball. When nodular adenomyosis of this size is present on a scan, it is usually misdiagnosed as uterine fibroids, another benign uterine condition that can be associated with pain and bleeding.
The bottom line is that in most cases adenomyosis will not be diagnosed by scanning and it will remain the doctor's clinical impression that it is present. Scans have only two possible results: the scan will either be completely normal or the scan will identify some abnormality (which may not even be related to the uterus).
If the scan is normal, the patient will still hurt. If the scan is abnormal, the patient will still hurt. Thus we are back to the doctor's opinion which will be based almost entirely on the medical history and physical exam. While this may seem archaic, remember that you are paying your doctor to exercise judgment based on the available evidence, and you will frequently have to trust him or her.
The visual appearance of the uterus at surgery is not always helpful in diagnosing adenomyosis. In many cases, the uterus may appear to be completely normal. In this case, the adenomyosis is contained entirely within the muscle wall and may not be associated with any enlargement of the uterus.
Occasionally, the doctor may palpate (touch) the uterus with a probe at laparoscopy or with the fingers at laparotomy and describe it as feeling "boggy," this term indicating a sense that the uterus is softer and spongier than average. "Bogginess" is somewhat of a soft call, since the uterus can occasionally be slightly enlarged and "boggy" in women who have had children, even if no adenomyosis is present.
In some patients, nodules of adenomyosis may be present, but they will resemble fibroids, so the diagnosis can be misleading. In a few patients, the adenomyosis may have erupted to the surface with resultant discoloration that will be obvious to the eye.
Like scans, the visual appearance of the uterus at surgery has only two possible variations. The uterus may appear to be completely normal, or it may appear to have some abnormality. If the uterus looks normal, the patient will still hurt. If the uterus looks abnormal, the patient will still hurt. The ball is back in the court of the doctor's opinion.
Biopsy of the uterus is possible, either at hysteroscopy or at laparoscopy. However, the surgeon typically has no obvious target to biopsy, and a blind biopsy must be done. Like scans of the uterus and the visual appearance of the uterus, a blind biopsy will have only two possible outcomes: it will either be entirely normal or it may show some abnormality such as adenomyosis. If the biopsy is normal, the patient will still hurt and may have adenomyosis hidden elsewhere under the surface of the uterus. So the biopsy can be misleading and hasn't helped the patient's pain. If the biopsy shows adenomyosis, the patient will still hurt and the presumption is usually made that the rest of the uterus is probably involved by adenomyosis.
Whether it is a scan, the visual appearance of the uterus at surgery, or blind biopsy, the doctor must ask the question, "What will I do with the results of this test?". If the results are normal, will the patient be told that there is nothing wrong and that her symptoms aren't real? Hopefully not.
If the results are abnormal, do they point toward anything specific which can be treated with a high probability of pain relief without removal of the uterus? Usually not.
In most cases the only way to diagnose adenomyosis with certainty is to remove the uterus and see if adenomyosis is present under the microscope. Even then, up to 15% of patients with clear-cut uterine symptoms of pain and bleeding will have no obvious finding under the microscope. This does not mean that these patients had unnecessary hysterectomies, since they are finally cured of their symptoms. It just means we aren't smart enough to know all the ways the uterus can misbehave.
Diagnosis and the ultimate treatment of adenomyosis both require hysterectomy. If a patient has symptoms and signs of adenomyosis and has completed her childbearing career, then removal of the uterus will provide the highest chance of relief of uterine symptoms with the lowest chance of future surgery for those symptoms.
Given the inability of scans to diagnose the disease, and since results of scans or even biopsies would not enlarge the treatment options for significant uterine symptoms, it is certainly acceptable and common for gynecologists to recommend hysterectomy on the basis of medical history and physical findings alone, with no further testing.
Removal of the uterus does not treat endometriosis, so endometriosis should be removed if it is found during the hysterectomy for adenomyosis. Women with significant uterine symptoms are typically thrilled with how they feel after removal of the uterus.
It is not necessary to remove the ovaries to treat adenomyosis since the condition affects only the uterus. Of course, some women have the bad luck of having ovarian problems such as pain or cysts. Such women can sometimes benefit from removal of the ovaries as well.
Medical treatment may be an option for women who have not completed their childbearing careers or who are not quite ready for removal of the uterus. Since no medicine eradicates adenomyosis, medical treatments are frustrating for patients as well as physicians and at best may mask some symptoms, occasionally with accompanying side effects.
Since the uterus is a hormonally responsive organ, hormones are the mainstay of medical treatment of symptoms. Your doctor may prescribe birth control pills or progesterone pills or shots. Although gonadotropin-releasing hormone agonists such as Lupron have been found to reduce uterine symptoms of adenomyosis during treatment, the symptoms return quickly after the medicine wears off.
Pain pills, whether over the counter or prescription, can be used to tide the patient over rough spots. These may only incompletely mask symptoms and narcotics can have long term problems of tolerance or even addiction.
Adenomyosis is a common cause of uterine symptoms in women over the age of 30. In the end, diagnosis of adenomyosis depends primarily on a thorough review and understanding of the woman's personal medical history and information from a physical examination. Removal of the uterus is the best treatment currently available for this condition.