What is the cause of right upper quadrant (RUQ) colic in a patient who is nil per os (NPO)?

From the Guidelines

The most likely cause of right upper quadrant (RUQ) colic in a patient who is nil per os (NPO) is biliary pathology, such as cholecystitis, cholelithiasis, or biliary colic, which should be investigated promptly using imaging studies like US, MRI, or CT. The patient's presentation with RUQ pain, fever, and elevated WBC count suggests a possible diagnosis of acute cholecystitis, which can be confirmed by imaging studies like US or MRI 1.

Diagnostic Approach

The diagnostic approach to RUQ pain should involve a step-wise approach, starting with a thorough history and physical examination, followed by laboratory tests and imaging studies.

• US is a useful initial imaging modality for evaluating the gallbladder and bile ducts, and can help identify gallstones, gallbladder inflammation, and bile duct dilation.
• MRI with MRCP can provide more detailed information about the biliary system and help distinguish between acute and chronic cholecystitis 1.
• CT with IV contrast can also be used to evaluate the patient, especially if US or MRI are not available or if the patient has a high risk of complications like gangrene or perforation.

Management

While investigating the underlying cause of RUQ pain, it is essential to manage the patient's pain and discomfort.

• Parenteral analgesics like IV ketorolac or IV morphine can be used to control pain, while maintaining the patient's NPO status.
• Antispasmodics like hyoscine butylbromide may also be helpful if the pain has a spasmodic component.
• The patient's medication regimen should be monitored closely for side effects, and pain should be reassessed regularly to ensure adequate control.

Recent Evidence

A recent study published in the Journal of the American College of Radiology in 2019 1 highlights the importance of imaging studies in evaluating RUQ pain, and provides guidance on the appropriate use of US, MRI, and CT in this setting.

• The study recommends that US be used as the initial imaging modality, followed by MRI or CT if the diagnosis is unclear or if complications are suspected.
• The study also emphasizes the importance of considering alternative diagnoses, such as peptic ulcer disease, pancreatitis, and bowel obstruction, in patients with RUQ pain.

From the FDA Drug Label

• Hepatotoxicity: Inform patients that severe hepatotoxicity (including acute hepatitis and fatal events) has been reported in patients taking ciprofloxacin tablets Instruct patients to inform their physician if they experience any signs or symptoms of liver injury including: loss of appetite, nausea, vomiting, fever, weakness, tiredness, right upper quadrant tenderness, itching, yellowing of the skin and eyes, light colored bowel movements or dark colored urine

The cause of right upper quadrant (RUQ) colic in a patient who is nil per os (NPO) may be hepatotoxicity associated with ciprofloxacin use, as evidenced by right upper quadrant tenderness being a sign or symptom of liver injury 2.

From the Research

Causes of Right Upper Quadrant (RUQ) Colic

• The cause of right upper quadrant (RUQ) colic in a patient who is nil per os (NPO) can be attributed to various factors, including gallbladder and biliary disease, as well as conditions affecting other organ systems such as the liver, pancreas, adrenal glands, kidneys, gastrointestinal tract, vascular system, and thoracic cavity 3.
• Acute cholecystitis is the most common diagnosable cause of RUQ pain in patients presenting to the emergency department, but over one-third of patients initially thought to have acute cholecystitis actually have RUQ pain attributable to other causes 3.
• Ultrasonography (US) is the primary imaging modality of choice for initial imaging assessment and can help identify a variety of ultrasonographically diagnosable disease processes, including conditions of hepatic, pancreatic, adrenal, renal, gastrointestinal, vascular, and thoracic origin 3, 4.

Differential Diagnosis

• The differential diagnosis for RUQ colic includes renal colic, which can be caused by kidney stones, and other conditions such as hepatic and biliary disease, pancreatic disease, and gastrointestinal disorders 5, 6, 7.
• Renal colic is a common condition that affects up to 12% of the population and can be managed with a combination of parenteral opioids and NSAIDs, as well as other treatments such as desmopressin and alpha-adrenoceptor antagonists 5, 6, 7.
• The choice of initial analgesia and route of administration for renal colic is important, with intramuscular non-steroidal anti-inflammatory drugs offering the most effective sustained analgesia and having fewer side-effects compared to opioids 5.

Diagnostic Imaging

• Ultrasonography (US) is a valuable tool in the diagnosis of RUQ colic, allowing for the identification of various disease processes and guiding further management 3, 4.
• Computed tomography (CT) and other imaging modalities may also be used to further evaluate patients with RUQ colic, depending on the clinical situation and US findings 3, 4.