Symptoms of HUS
What are the Signs and Symptoms of Post Diarrheal Hemolytic Syndrome (D+HUS) and how is the Diagnosis Made?
The bowel inflammation that occurs prior to the onset of hemolytic uremic syndrome is generally referred to as the prodrome. Usually within a week (although the range can be 1-10 days) after ingesting Shiga toxin-producing E. coli, the colon becomes severely inflamed, causing diarrhea that soon becomes bloody.
A stool specimen obtained within the first 10 days of illness is usually positive for E. coli O157:H7 or Shiga toxin. However, in many patients the window for capturing E. coli O157:H7 is narrow.
During the prodromal phase of HUS, the initial diagnosis is often acute surgical abdomen, acute appendicitis, or ulcerative colitis. The large bowel inflammation (colitis) can be mistaken for acute appendicitis because the site of intense inflammation is in the right lower part of the abdomen. If this leads to an appendectomy, the appendix is almost always found to be normal, but the surrounding bowel is swollen and hemorrhagic. If a colonoscopy is conducted, severe inflammation, ulceration and pseudomembranes (comprised of sloughed mucosal cells, white blood cells and fibrin) are found.
If computerized tomography (CT) of the abdomen is performed, a thickened (inflamed) bowel is usually identified. Following several days of diarrhea, thrombocytopenia (low platelet count), hemolytic anemia, and acute renal failure converge to form the trilogy that defines HUS.
What are the Physical Signs and Laboratory Values on Admission to the Hospital with HUS?
Physical findings on admission to the hospital may include lethargy, abdominal tenderness, bruising (purpura), swelling, or dehydration. Features on admission that portend a severe or fatal outcome include coma, rectal prolapse, decreased or absent urine output (oligoanuria), or an elevated white blood cell count (WBC)—one greater than 20 x 10^9/l (i.e. greater than 20,000 per liter).