Abdominal rigidity is a stiffness of your stomach muscles that occurs when the abdomen is touched. This is an involuntary response to prevent pain caused by pressure on your abdomen. Another term for this protective mechanism is “guarding.”
This symptom is not the same as intentionally flexing your abdominal muscles or the rigidity associated with severe gas. Guarding is a completely involuntary response of the muscles. In other words, you have no control over it. It is a sign that your body is trying to protect itself from pain and can be a symptom of a very serious and even life-threatening medical condition.
If you have abdominal rigidity, you should see your doctor right away.
Abdominal rigidity and pain often occur together. Every condition that causes abdominal pain can cause guarding. Disorders of your abdominal organs can cause abdominal pain. Organs inside your abdomen include your:
- small and large intestines
- aorta (main artery)
- vena cava (main vein)
- kidneys and ureters
Problems with your pelvic organs can also cause abdominal pain. Your pelvic organs include:
- bladder and lower ureters
- uterus, fallopian tubes, and ovaries (in women)
- prostate gland (in men)
It is less common to find diseases of the lower lung as a cause of abdominal pain and rigidity, but it does sometimes happen.
Abdominal rigidity is a medical emergency. Symptoms of greatest severity that could mean that you are in a life-or-death situation include:
- vomiting blood (also called hematemsis)
- rectal bleeding
- black, tarry stools (this is associated with bleeding from the stomach or small intestines)
- inability to eat or drink anything
- severe vomiting
- increased abdominal girth (distended abdomen)
- shock (very low blood pressure)
Other symptoms include:
- yellowing of the skin or jaundice
- loss of appetite (anorexia)
- feeling of fullness after eating small amounts of food (early satiety)
- inability to pass gas from the rectum
- pale skin
The location of pain varies with the location of the organ that is causing the problem. For medical purposes, your stomach is divided into four sections called quadrants. For instance, stomach ulcers can cause pain in the left upper quadrant of your abdomen where they are located. Gallstones can cause right upper quadrant pain, because they are located in the upper right part of your abdomen.
Abdominal pain can also travel to other areas of the abdomen. Appendicitis can start off as right lower quadrant pain, but the pain can start to move toward your belly button.
The causes of abdominal pain (and rigidity) can be different based on age.
Adults (most common in elderly adults):
- abscess inside the abdomen
- cholecystitis (gallbladder inflammation)
- bowel obstruction or blockage
- perforation or hole in the intestines, stomach, or gall bladder
- trauma to the abdomen
- painful menstruation (dysmenorrhea)
- pelvic inflammatory disease (from sexually transmitted infections)
- ovarian cysts
- pregnancy (includes ectopic)
- peritonitis (inflammation of the tissue lining the abdomen)
- urinary tract infections (UTIs)
- ingested toxins (poisons)
- gastroenteritis (digestive irritation caused by a virus)
- viral infection
- pyloric stenosis (narrowing of the stomach outlet)
If you have involuntary abdominal rigidity, you should see a doctor right away to rule out serious problems. Although something as minor as a stomach virus could cause guarding, you will not know until your doctor gives you a proper diagnosis.
Do not attempt to take medication to dull the pain before seeing your doctor. It will alter the pain pattern and make it more difficult for your doctor to diagnose your condition.
When you talk to your doctor, it is helpful for you to be aware of the following:
- when the symptoms started
- qualities of the pain (if it’s dull, sharp, occurring off and on, or travels to another area)
- how long the pain lasts
- what you were doing when the rigidity/pain began
- what makes it better
- what makes it worse
- other symptoms and when they started
- time of your last meal (in case you need surgery)
Being aware of these factors will help your doctor establish your diagnosis.
The first steps in finding the cause of abdominal rigidity are to discuss your medical history. A physical exam will usually reveal the cause. Your doctor may order the following tests:
- CBC (complete blood count)
- serum electrolytes (potassium, sodium, chloride, bicarbonate)
- BUN (blood urea nitrogen)
- creatinine (indication of kidney functioning)
- liver function tests
- test for blood in your stool
Additional tests include:
- abdominal X-rays (to evaluate for obstruction or perforation)
- abdominal ultrasound (uses sound waves to make images of abdominal organs)
- abdominal CT scan (uses high-resolution X-rays to make images of your abdominal organs)
The treatment your doctor chooses to use will depend on the cause of the abdominal rigidity. Obviously, treatment for colic in an infant will be different than treatment for cancer, for instance. While more minor conditions may only require monitoring, self-care, and prescription antibiotics, more serious causes of abdominal rigidity could warrant more aggressive treatments.
Depending on your diagnosis, aggressive treatment can include:
- intravenous fluids to prevent dehydration
- nasogastric (feeding) tube to provide nourishment
- intravenous antibiotics
Untreated causes of abdominal rigidity can be fatal. Abdominal infection can cause bacteria to enter the blood. This can cause your blood pressure to fall dangerously low (shock). Severe blood loss can also cause death. Dehydration and electrolyte imbalance from prolonged vomiting can cause dangerous heart rhythm problems, shock, and kidney failure.