Scientists have decoded an extremely rare case in which a Chinese woman with diabetes was periodically hospitalized for severe vomiting more than 30 times in a few days.
The 27-year-old woman, according to a study published last month in the journal Frontiers in Endocrinologyhave type 1 diabetes (T1D), an autoimmune disease in which a person’s immune system attacks the healthy cells in their pancreas that produce the hormone insulin.
An additional autoimmune disorder due to genetic factors and dysregulated immunity is suffered by one in five individuals who have T1D, the researchers, including those at the University of Hong Kong, pointed out.
They suspect the woman’s autoimmune disease may be causing her to vomit, with the volume sometimes found in litres.
“The episodes were so severe that the patient vomited more than 30 times a day and the vomit volume could be up to six liters,” the scientists wrote in the study.
Doctors reportedly first examined the patient in 2016. Since then, she has been hospitalized “almost once a month” with primary complaints of vomiting and abdominal pain.
Whenever the woman experienced a full-blown vomiting episode, she had a “sense of impending doom” and came to the hospital in a state of panic.
Within hours of admission, she was feeling nausea, vomiting, and relentless retching along with abdominal pain, and was in a manic mood due to the “unbearable” pain.
The patient underwent several tests, including an intensive physical examination of the whole body and imaging diagnoses such as ultrasound, endoscopy, CT scan and MRI to find out if there were any pathogenic factors causing the vomiting and abdominal pain.
But doctors found no significant findings from these evaluations.
The woman’s gastric emptying tests — which assess how long it takes for food to empty from her stomach — were normal. Blood cell counts and urine and stool tests were also normal.
In her blood plasma, doctors found extremely high levels of antibodies to an enzyme produced by the pancreas, despite the fact that it had been nearly 12 years since she was diagnosed with T1D.
They diagnosed the 27-year-old with ‘cyclic vomiting syndrome’ (CVS), a disorder in which patients experience sudden bouts of vomiting interspersed with long periods without symptoms.
While the patient’s vomiting subsided within days of admission, her blood sugar would plummet and stay low for days, the researchers pointed out.
Scientists are still trying to uncover the exact mechanism behind the 27-year-old’s symptoms, specifically what appeared to have caused her blood sugar levels to drop.
“We observed an unusual ‘insulin recycling’ phenomenon in this patient, where the hormone re-entered the bloodstream instead of being efficiently broken down by cells,” said Aimun Xu, one of the case study authors. Live science.
“Although extremely rare, antibodies to both endogenous and exogenous insulin are capable of inducing intractable hypoglycemia by binding with insulin and disrupting its normal function,” explained the researchers in the study.
Doctors then tried Rituximab, a drug that tags certain antibody-producing immune cells for destruction.
They found that it reduced the number of antibodies attacking the patient’s insulin-producing cells.
It also corrected her low blood sugar and reduced her cyclical vomiting episodes.
“Rituximab treatment to suppress AIs [an antibody type] was associated with marked improvement in hypoglycemia. Unexpectedly, episodes of cyclic vomiting were also dramatically reduced,” the scientists wrote in the study.
The researchers suspect that CVS may be a separate autoimmune disease that needs to be studied further, and they hope to conduct clinical trials of rituximab against the condition.