Ultrasound Evidence of Acute Appendicitis in a Patient with Hemolytic Uremic Syndrome

Introduction: Hemolytic uremic syndrome (HUS) is a clinical syndrome characterized by microangiopathic hemolytic anemia, thrombocytopenia, and acute kidney injury. Children with HUS often present with gastrointestinal complaints, including abdominal pain, vomiting, and diarrhea. This presentation can mimic other gastrointestinal illnesses, including appendicitis, which further adds to the known diagnostic challenge. Case Report: We report an 8-year-old male who presents with abdominal pain and diarrhea-associated HUS. Kidney ultrasound obtained for acute kidney failure showed incidental findings of dilated appendix which were confirmed on a follow-up appendix ultrasound. Patient lacked the typical findings of acute appendicitis such as fever, abdominal tenderness or rigidity. We observed the patient without medical or surgical treatment for acute appendicitis as ultrasound findings were attributed to HUS, and the patient’s abdominal pain and HUS resolved without any intervention. Conclusion: Self-limited appendiceal inflammation may be seen in diarrhea-associated HUS, and the diagnostic utility of appendix ultrasound to evaluate for acute appendicitis may be limited in a patient with HUS and abdominal pain.

___

  • 1. Whitington PF, Friedman AL, Chesney RW. Gastrointestinal disease in the hemolytic-uremic syndrome. Gastroenterology 1979;76:728-33.
  • 2. Edmonson MB, Chesney RW. Hemolytic-uremic syndrome confused with acute appendicitis. Arch Surg. 1978;113(6):754-5.
  • 3. Tune BM, Leavitt TJ, Gribble TJ, et al. The hemolytic-uremic syndrome in California: A review of 28 nonheparinized cases with long-term follow-up. J Pediatr. 1973;82(2):304-310.
  • 4. De la hunt MN, Morris KP, Coulthard MG, et al. Oesophageal and severe gut involvement in the haemolytic uraemic syndrome. Br J Surg. 1991;78(12):1469-72.
  • 5. Fenton SJ, Kastenmeier A, Pysher TJ, et al. Acute appendicitis in a patient with hemolytic uremic syndrome: an unusual clinical scenario. Pediatr Surg Int. 2008;24(4):439-41.
  • 6. Jokiranta TS. HUS and atypical HUS. Blood. 2017;129(21):2847-2856.
  • 7. Mayer CL, Leibowitz CS, Kurosawa S, et al. Shiga toxins and the pathophysiology of hemolytic uremic syndrome in humans and animals. Toxins (Basel). 2012;4(11):1261-87.
  • 8. Talarico V, Aloe M, Monzani A, et al. Hemolytic uremic syndrome in children. Minerva Pediatr. 2016;68(6):441-455.
  • 9. Siegler RL. Spectrum of extrarenal involvement in postdiarrheal hemolytic-uremic syndrome. J Pediatr. 1994;125(4):511-8.