Background and Objective: The most common cause of acute kidney injury (AKI) in children is hemolytic uremic syndrome (HUS). HUS is characterized by the triad of thrombocytopenia, non-immune hemolytic microangiopathic anemia, and AKI. HUS has no specific manifestations, but it usually presents with fatigue, pallor and decreased urine output. Abdominal pain is one of the symptoms usually caused by Shiga toxin-producing E. coli, although fever is rare. Severe gastrointestinal tract involvement occurs in 5 to 10% of cases. The patient described presented with diarrhea, vomiting and abdominal pain and underwent surgery for an acute abdomen with a diagnosis of toxic megacolon. This is a rare complication of HUS.
Case report: A 7-year-old boy was admitted to the emergency room with fever, vomiting, and bloody diarrhea and received conservative treatment. On the second day, the abdominal pain worsened and he had tenderness and guarding on examination, which was diagnosed as acute abdomen. After the diagnosis of acute abdomen, surgery was performed, which led to a diagnosis of toxic megacolon. The day after surgery, the patient became pale and oliguric. The patient's tests included Hb: 7.5gr/dl, PLT: 67000ml, Cr: 2.5 mg/dl, BUN: 42mg/dl, LDH: 3320 U/L and schistocytes were observed on the peripheral blood smear, the patient was diagnosed with HUS and underwent hemodialysis treatment.
Conclusion: This case reminds us that HUS can present with very rare symptoms such as toxic megacolon. Therefore, it is necessary to be familiar with all the symptoms of HUS.