Man’s aHUS likely triggered by acute pancreatitis, scientists say
Signs of hemolysis end with treatment for inflammation in pancreas alone
A 68-year-old man was diagnosed with atypical hemolytic uremic syndrome (aHUS) that, in an “extremely rare case,” appeared to have been triggered by acute pancreatitis, or inflammation of the pancreas, according to a recent case report.
The patient was admitted to a hospital in Japan with lower abdominal pain. A CT scan identified pancreatitis, and laboratory tests found signs of intravascular hemolysis, or red blood cell destruction inside blood vessels.
He improved with treatment for the pancreatitis, and his aHUS resolved without a therapy being given.
The report, “Atypical Hemolytic Uremic Syndrome Secondary to Pancreatitis: A Case Report,” was published in the journal Cureus.
aHUS secondary to acute pancreatitis ‘extremely rare’
aHUS is marked by the abnormal activation of the complement cascade, part of the immune system. This triggers inflammation and blood clot formation in small blood vessels.
This rare disorder is a type of thrombotic microangiopathy (TMA), a group of diseases marked by the formation of blood clots in the body’s small blood vessels, which can lead to organ damage.
Infections are known to be a common aHUS trigger. Some medications can also lead to its onset, as can some types of cancer, autoimmune diseases, and pregnancy.
A direct relationship between known triggers of acute pancreatitis, such as heavy alcohol consumption or high cholesterol levels, and TMA is not known, although the scientists noted that “pancreatitis itself may trigger TMA.”
To date, “cases of aHUS triggered by acute pancreatitis are extremely rare in the literature,” they wrote.
The man had no family history of blood clotting problems and was not a heavy alcohol drinker. He was being treated for diabetes, high blood pressure, and high cholesterol/triglycerides, or elevated levels of fatty molecules in the blood.
Sudden pain in the lower abdomen, combined with nausea and vomiting, led him to seek treatment at a local hospital.
A CT scan revealed severe acute pancreatitis, and the patient was transferred to the scientists’ hospital, in Kurume, for treatment.
A physical examination revealing jaundice (yellowing) in his eyes, but there was no evidence of anemia. Exams also showed tenderness in the middle lower portion of the abdomen and reduced intestinal peristalsis, the wave-like muscle contractions that help move food through the digestive system.
Signs indicated macroscopic hemoglobinuria, with the patient’s urine displaying an orange to red color. This can occur when red blood cells are destroyed and their contents, including hemoglobin, are released into the bloodstream. At excessive levels, hemoglobin — the protein in red blood cells that’s responsible for oxygen transport — can appear in the urine, causing it to change color.
A CT scan found signs of inflammation in the pancreas and surrounding areas of the abdominal cavity.
With these findings, the scientists considered a TMA diagnosis, most likely caused by acute pancreatitis.
After several tests that allowed them to exclude other forms of TMA, they concluded that aHUS, specifically, was causing his symptoms.
The man started treatment for pancreatitis on his first day at the hospital, and the abdominal symptoms eased and hemoglobinuria “resolved” the next day, the scientists reported.
Laboratory tests also confirmed that pancreatitis treatment addressed the hemolysis in the absence of any aHUS-specific treatment.
A later CT scan, given after seven days, also showed that inflammation in and around the pancreas had eased. As a result, two of the three pancreatitis medicines were stopped. Since there were no complications almost a month after his admission, the man then was transferred to his local hospital.
“When hemolytic anemia is a complication of pancreatitis, the cause of hemolysis must be differentiated,” the scientists wrote, adding that “aHUS should be suspected.”
“Clinicians should be aware that acute pancreatitis may be a potential cause of aHUS,” they noted.