What laboratory tests are indicated for a patient presenting with nausea for over two weeks, without known dietary changes, and accompanied by mild abdominal pain?

From the Guidelines

For persistent nausea over two weeks with mild abdominal pain and no known diet changes, I recommend a comprehensive laboratory workup including complete blood count (CBC), comprehensive metabolic panel (CMP), lipase, amylase, thyroid stimulating hormone (TSH), urinalysis, and pregnancy test if applicable, as suggested by the most recent and highest quality study 1.

The CBC can identify infections or inflammation, while the CMP assesses liver, kidney, and electrolyte status. Lipase and amylase help evaluate for pancreatitis, which can cause persistent nausea. Thyroid function tests are important as thyroid disorders can manifest with gastrointestinal symptoms. A urinalysis can detect signs of infection or ketones suggesting metabolic issues.

Additionally, an abdominal ultrasound would be valuable to examine the gallbladder, liver, and pancreas, as gallstones or other structural abnormalities could explain these symptoms, as noted in the study 1. If symptoms are severe or accompanied by warning signs like weight loss, blood in stool, or vomiting, more urgent evaluation with endoscopy might be warranted.

The study 1 highlights the importance of a careful history and physical examination in assessing patients with nausea and vomiting, and the need to differentiate between various conditions that may cause these symptoms. However, the most recent study 1 provides more relevant guidance on the laboratory workup and imaging studies that should be performed in this scenario.

Some key points to consider when evaluating a patient with persistent nausea and mild abdominal pain include:

• The need for a comprehensive laboratory workup to rule out underlying infections, inflammation, or metabolic disorders
• The importance of imaging studies, such as abdominal ultrasound, to evaluate for structural abnormalities
• The potential need for more urgent evaluation with endoscopy if symptoms are severe or accompanied by warning signs
• The importance of considering the patient's overall clinical presentation and medical history when determining the appropriate course of evaluation and treatment, as noted in the study 1.

From the Research

Laboratory Tests for Nausea and Abdominal Pain

To evaluate nausea and mild abdominal pain over two weeks with no known diet changes, several laboratory tests can be considered:

• Complete blood count (CBC) to check for signs of infection or inflammation 2, 3, 4
• Comprehensive metabolic panel (CMP) to evaluate electrolyte levels and kidney function 2, 3, 4
• Urinalysis to check for urinary tract infections or other abnormalities 2, 3
• Urine pregnancy testing to rule out pregnancy as a cause of nausea 2, 3
• Amylase and lipase levels to evaluate for pancreatitis 2
• Thyroid-stimulating hormone (TSH) level to check for thyroid disorders 2
• Stool studies with cultures to check for gastrointestinal infections 2

Imaging Studies

Imaging studies may also be necessary to evaluate the cause of nausea and abdominal pain:

• Abdominal radiography to check for intestinal obstruction or other abdominal abnormalities 3, 4
• Ultrasonography to evaluate the gallbladder, liver, and other abdominal organs 3
• Computed tomography (CT) scan to evaluate the abdomen and pelvis for various causes of nausea and abdominal pain 2, 3, 4

Additional Considerations

It is essential to consider the patient's medical history, physical examination findings, and other symptoms when selecting laboratory tests and imaging studies. The presence of alarm signs such as dehydration, acidosis, or acute abdomen may warrant additional evaluation 2. If gastroparesis is suspected, a gastric emptying study may be recommended 2.