Key Takeaways
A 68-year-old man presented with persistent abdominal bloating and constipation for 7 days. Initial assessments suggested bowel obstruction, which was supported by physical examination and abdominal x-ray findings.
However, an abdominal CT scan revealed an intimal flap at the T10-L1 level with an associated intramural haematoma, confirming a diagnosis of Stanford type B aortic dissection.
Muoyly Pav, MD, a paediatrician at Sunrise Japan Hospital Phnom Penh, Phnom Penh, Cambodia, described this rare case of aortic dissection (AD).
The Patient and His History
The patient reported no episodes of chest pain, tearing abdominal pain, nausea, or vomiting. On arrival, his vital signs were as follows: body temperature, 36.2 °C; heart rate, 84 beats/min; respiratory rate, 19 breaths/min; and blood pressure, 135/97 mm Hg.
Findings and Diagnosis
Physical examination revealed mildly decreased bilateral pulmonary air entry, attributed to abdominal distension, accompanied by hypoactive bowel sounds on abdominal auscultation. No other abnormal findings were noted. Laboratory evaluation showed elevated dyslipidaemia, with a low-density lipoprotein (LDL) level of 155 mg/dL. However, other measured parameters, including liver function, electrolytes, and complete blood cell count, were within normal limits as follows:
- Total bilirubin: 0.9 mg/dL (reference range: 0.2-1.0 mg/dL)
- Direct bilirubin: 0.3 mg/dL (reference range: 0-0.3 mg/dL)
- Aspartate aminotransferase: 72 U/L (reference range: 15-37 U/L)
- Alanine aminotransferase: 50 U/L (reference range: 16-63 U/L)
- Gamma-glutamyl transferase: 49 U/L (reference range: 15-85 U/L)
- Amylase: 60 U/L (reference range: 25-115 U/L)
- Total cholesterol: 224 mg/dL (reference range: 0-200 mg/dL)
- High-density lipoprotein cholesterol: 22 mg/dL (reference range: 40-60 mg/dL)
- LDL cholesterol: 155 mg/dL (reference range: 0-99.9 mg/dL)
- Triglycerides: 166 mg/dL (reference range: 0-150 mg/dL)
- Blood urea nitrogen: 8 mg/dL (reference range: 7-18 mg/dL)
- Creatinine: 0.94 mg/dL (reference range: 0.8-1.3 mg/dL)
- Sodium: 139 mEq/L (reference range: 136-145 mEq/L)
- Chloride: 102 mEq/L (reference range: 98-107 mEq/L)
- Potassium: 3.5 mEq/L (reference range: 3.5-5.1 mEq/L)
- Serum glucose: 108 mg/dL (reference range: 74-106 mg/dL)
- Haemoglobin A1c: 6.0% (reference range: 4.5-6.4%)
- C-reactive protein: 5.2 mg/dL (reference range: 0-0.3 mg/dL)
- White blood cell count: 8120/μL (reference range: 3900-9800/μL)
- Red blood cell count: 4.24 × 10⁶/μL (reference range: 4.27-5.70 × 10⁶/μL)
- Haemoglobin: 12.6 g/dL (reference range: 13.5-17.6 g/dL)
- Haematocrit: 37.1% (reference range: 39.8%-51.8%)
- Mean corpuscular volume: 87.5 fL (reference range: 82.7-101.6 fL)
- Mean corpuscular haemoglobin: 29.7 pg (reference range: 28.0-34.6 pg)
- Mean corpuscular haemoglobin concentration: 34% (reference range: 31.6%-36.6%)
- Platelet count: 450,000/μL (reference range: 131,000-362,000/μL)
- Neutrophils: 53.7% (reference range: 40%-70%)
- Basophils: 0.5% (reference range: < 1%)
- Eosinophils: 13.1% (reference range: 1%-6%)
- Lymphocytes: 23.6% (reference range: 20%-40%)
- Monocytes: 9.1% (reference range: 2%-10%)
Chest x-ray demonstrated no mediastinal widening, no enlargement of the aortic knob, and no evidence of cardiomegaly. An abdominal x-ray revealed an air-fluid level on the right side, while the left side showed bowel distension without an air-fluid level. A small amount of gas was observed in the lower right quadrant, and the gas distribution was uneven.
Because bowel obstruction and ileus could not be excluded on the basis of the x-ray findings, a contrast-enhanced abdominal CT scan was performed. The scan revealed an intimal flap at the T10-L1 level, with an associated intramural haematoma extending from the descending aorta into the abdominal aorta, with a maximum thickness of 9 mm.
Notably, there were no signs of organ damage (malperfusion syndrome) or pleural effusion in either lower lung. CT angiography of the aorta was then performed to assess the extent of the AD, and it demonstrated no dissection at the aortic arch.
On the basis of these imaging findings and clinical symptoms, the patient was diagnosed with uncomplicated Stanford type B AD and secondary ileus.
He was admitted to the ICU and started on bisoprolol 2.5 mg and valsartan 80 mg to manage his blood pressure and heart rate. After admission, the patient remained stable until discharge on day 7. Six days after discharge, the patient presented again with abdominal pain. Follow-up CT angiography of the aorta revealed no significant changes in AD.
His current condition was stable, with well-controlled systolic blood pressure maintained below 120 mm Hg with amlodipine 5 mg once daily.
Discussion
Clinicians should consider a differential diagnosis of AD when ileus-like symptoms are present without an identifiable cause, as some cases may be painless, increasing the risk for misdiagnosis and delayed treatment. Early identification and consideration of AD can lead to timely intervention, potentially reducing the morbidity and mortality associated with this serious condition. Clinicians should consider the differential diagnosis of AD when ileus-like symptoms are present without an identifiable cause.
This story was translated from Univadis Germany.