Differential Diagnosis for a 7-year-old child with fever, chills, nausea, vomiting, abdominal pain, and headache

• Single most likely diagnosis:
  • Viral gastroenteritis: This is a common condition in children, characterized by inflammation of the stomach and intestines, often due to a viral infection. Symptoms such as fever, chills, nausea, vomiting, abdominal pain, and headache are typical for this condition.
• Other Likely diagnoses:
  • Appendicitis: Although more commonly associated with localized abdominal pain, appendicitis can present with a variety of symptoms including fever, nausea, vomiting, and abdominal pain. The headache could be secondary to the systemic response to infection.
  • Urinary Tract Infection (UTI): UTIs can cause significant discomfort in children, including fever, chills, nausea, vomiting, and abdominal pain. The headache might be related to the systemic infection.
  • Influenza: Influenza can present with a wide range of symptoms including fever, chills, headache, nausea, and vomiting. Abdominal pain can sometimes be associated with influenza, especially in children.
• Do Not Miss (ddxs that may not be likely, but would be deadly if missed.):
  • Meningitis: Although less common, meningitis is a life-threatening condition that requires immediate medical attention. Symptoms can include fever, headache, nausea, vomiting, and sometimes abdominal pain. It's crucial to consider this diagnosis, especially if there are signs of neck stiffness or altered mental status.
  • Septicemia: Sepsis is a life-threatening condition that arises when the body's response to infection causes injury to its own tissues and organs. Symptoms can be non-specific and include fever, chills, nausea, vomiting, abdominal pain, and headache.
  • Intussusception: A condition where a part of the intestine slides into an adjacent part, potentially cutting off blood supply. It's more common in younger children but can occur at any age. Symptoms include abdominal pain, vomiting, and sometimes fever.
• Rare diagnoses:
  • Kawasaki Disease: An acute febrile illness of childhood characterized by inflammation in the walls of medium-sized arteries throughout the body. Symptoms include fever, abdominal pain, vomiting, and headache, among others.
  • Hemolytic Uremic Syndrome (HUS): Typically follows a bacterial infection, often with E. coli, and can cause fever, abdominal pain, and symptoms related to renal failure and hemolysis.
  • Brain abscess: A rare but serious condition that could present with headache, fever, nausea, vomiting, and sometimes abdominal pain if the abscess affects areas of the brain that regulate gastrointestinal function.