From the Guidelines
For a 5-year-old child with vomiting for one week, I strongly recommend a comprehensive laboratory workup including complete blood count (CBC), comprehensive metabolic panel (CMP), urinalysis, and stool studies to promptly identify potential underlying causes and guide appropriate management. The CBC will assess for infection or inflammation through white blood cell count and for dehydration through hematocrit 1. The CMP will evaluate electrolyte imbalances (particularly sodium, potassium, chloride, and bicarbonate), kidney function (BUN, creatinine), liver function (AST, ALT, bilirubin), and glucose levels. Urinalysis helps assess hydration status and rule out urinary tract infections. Stool studies should include culture for bacterial pathogens, ova and parasite examination, and testing for Clostridioides difficile if the child has had recent antibiotic exposure.
Considerations for the workup include:
- Clinical evaluation to differentiate between nonbilious and bilious vomiting, as the latter suggests a more distal obstruction 1
- Assessment for signs of dehydration, such as dry mucous membranes, decreased urine output, and lethargy, which may necessitate immediate IV fluid rehydration 1
- Abdominal ultrasound if there are concerns about appendicitis, intussusception, or other structural abnormalities
- The potential for various conditions ranging from viral gastroenteritis to more serious issues like intestinal obstruction, pancreatitis, or metabolic disorders, emphasizing the importance of a thorough laboratory evaluation for proper diagnosis and management 1.
Given the age of the child and the duration of vomiting, it is crucial to prioritize a comprehensive approach to identify any underlying serious conditions that could impact morbidity, mortality, and quality of life. The most recent and highest quality study 1 supports the importance of a thorough clinical evaluation and targeted laboratory tests in the assessment of vomiting in infants and young children, guiding the recommendation for a similar approach in this 5-year-old child.
From the Research
Laboratory Workup for Vomiting in a 5-Year-Old for 1 Week
- The clinical characteristics of rotaviruses disease, a major cause of viral gastroenteritis in infants and young children, include a wide spectrum of clinical signs and symptoms, such as diarrhea, vomiting, mild fever, and signs of respiratory infection 2.
- In the absence of acute abdominal pain, significant headache, or recent initiation of certain medications, acute nausea and vomiting is usually the result of self-limited gastrointestinal infections, and the likely cause can usually be determined by history and physical examination 3.
- Basic laboratory testing may include:
- Urinalysis
- Urine pregnancy testing
- Complete blood count
- Comprehensive metabolic panel
- Amylase and lipase levels
- Thyroid-stimulating hormone level
- Stool studies with cultures 3
- A comprehensive metabolic panel can help identify electrolyte abnormalities, such as potassium and chloride imbalances, as well as blood urea nitrogen and creatinine levels, which can reflect renal function and acid-base homeostasis 4
- Imaging studies, such as abdominal radiography, ultrasonography, and computed tomography, may be necessary if an acute abdomen or other underlying conditions are suspected 3