'Complete' twist of fallopian tube sent girl to hospital with sudden belly pain

Doctors discovered that a girl's sudden and mysterious belly pain had a rare cause: One of her fallopian tubes was completely twisted. 

This condition is rare, overall, but especially rare in children.

The 11-year-old girl's severe abdominal pain had come on over the course of a day and triggered nausea and vomiting, according to a recent report of the case, published Aug. 9 in the journal Case Reports in Surgery. At the emergency room, doctors found that the pain extended from the center of the girl's lower stomach below the belly button to the right side of her pelvis. Tests showed elevated levels of immune cells in her blood, and an ultrasound revealed that the muscles that normally move food through the digestive system were not contracting properly.  

Upon further examination, doctors discovered that the girl had a blob of excess fluid in her pelvis measuring about 2.3 by 2.8 by 1.9 inches (5.9 by 7.2 by 4.9 centimeters). However, her ovaries, located near the fluid buildup, seemed to be functioning normally and didn't have any obvious signs of damage. 

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The doctors performed an additional scan to look closer at the fluid and found that it was in contact with the girl's ovaries but wasn't coming directly from them. She also had extra fluid that was just floating "free" in her pelvis. Initially, they thought she might have an inflammatory disease in the pelvis that had caused a swollen mass to form in tissues of the reproductive system, or that it might be caused by a condition in another part of the body, like the intestines. 

Unsure of this fluid's mysterious cause, the team decided to conduct a type of surgery known as laparascopy, in which doctors make small incisions in the abdomen and guide a tiny camera inside. The procedure confirmed that the free fluid in her pelvis looked a lot like blood, and it revealed the source of that blood: the girl's left fallopian tube was completely twisted. This twist, or "torsion," caused a bleeding cyst to develop, which, in turn, stopped the flow of blood to the tube and led to tissue death. 

This rare condition, in which a fallopian tube gets twisted without affecting its nearby ovary, is known as isolated fallopian tube torsion (IFTT). It's slightly more common for ovaries to twist, or for an ovary and fallopian tube to twist together; but ovarian torsion is still relatively uncommon, affecting about 6 in 100,000 women in a year, a South Korean study found.  

By comparison, IFTT is estimated to affect around 1 in 1.5 million reproductive-age women worldwide, and it's even rarer in pediatric and postmenopausal populations. Most of the time, IFTT causes the right fallopian tube to twist, but 40% of cases occur in the left tube. 

The condition is difficult to diagnose, as there isn't one definite set of symptoms. Patients may have severe, sharp pain in their lower belly, which is often accompanied by nausea and vomiting. However, these common symptoms make IFTT easy to confuse with other conditions, such as appendicitis or urinary tract disease. 

The team had to remove the girl's left fallopian tube due to the dead tissue, but they were able to spare her right tube and both ovaries, and she completely recovered. The authors of the case report noted that the procedure could affect the patient's fertility in the future, but because she has both ovaries and an intact tube, "it is expected that it will not have major repercussions."  

They added that IFTT should be treated as quickly as possible, because delays of 10 hours or more can greatly increase the risk of tissue death. 

The exact cause of IFTT is unclear, but scientists have several theories as to why it happens, the authors added. Some theorize, for example, that it may be caused by abnormalities in the sheet of tissue that normally surrounds the fallopian tubes, or perhaps by problems in the fallopian tube itself that disrupt how it shuttles eggs to the uterus. Others say it may be driven by untreated infections that lead to fluid buildup; physical trauma; or "sudden changes in body position" that cause the reproductive organs to shift in an odd way. 

The 11-year-old didn't have any known risk factors for torsion upon arriving at the emergency room. "However, she did have a large tubal cyst, which likely facilitated torsion," meaning it likely exacerbated the twist as it formed, the authors noted.