P0874 - An Unusual Presentation of Volvulus Revealed a Rare Variant of Heterotaxy Syndrome: A case Report

Heterotaxy with asplenia, also referred to as situs ambiguous with asplenia, is a rare congenital condition resulting from abnormal arrangement of organs in the abdominal and thoracic cavities during embryologic development. It is characterized by disruption of the normal left-right axis orientation of visceral organs. Heterotaxy is divided into incomplete lateralization (i.e., heterotaxy) and complete (i.e., situs inversus totalis). Cardiac anomalies are major manifestations of heterotaxy that leads to early detection of such a syndrome. This case report demonstrates an unusual presentation of volvulus in a five-year old female who was unexpectedly found to have heterotaxy syndrome with asplenia in absence of cardiac malformation.

We report the case of a five-year old previously healthy female who presented with abdominal pain for 1 day followed by non-bloody, non-bilious vomiting. On exam, patient was afebrile, tachycardic, tachypneic but normotensive. Oxygen saturation: 98% in room air. She was awake and alert. Lungs were clear. Normal heart sounds and no murmurs. Well perfused. Abdomen soft, non-tender but distended, no guarding, rigidity nor organomegaly. No skin rash. Rest of physical exam was normal.

Complete blood count was significant for leukocytosis of 22,000/uL and bandemia of 21%. Hyperglycemia of 400 mg/dL with high anion gap metabolic acidosis in light of pH: 7.12, bicarbonate: 10 mmol/L and anion gap: 26. High blood urea nitrogen: 19 mg/dL and creatinine: 1.6 mg/dL. With presumptive diagnosis of diabetic ketoacidosis (DKA), patient was admitted to intensive care unit. Further labs showed normal β-hydroxybutyrate and urinalysis showed no ketones or glucose. Worsening acidosis on repeated labs raised concern for another underlying problem. Lactic acid found to be elevated at 17 mmol/L. Perfusion worsened and patient became hypotensive requiring multiple fluid boluses, pressors and antibiotics due to presumed septic shock. Cardiac echocardiogram was normal. Abdominal CT-scan was done due to worsening abdominal distension; surprisingly showed swirling of mesentery highly concerning for midgut volvulus with ischemic changes and remarkable abdominal situs ambiguous with asplenia. During emergent laparotomy, small bowel and proximal colon were found to be malrotated, volvulized, black and nonviable. Necrotic segments were resected, which left the patient with approximately 10 cm of small bowel.

In situs ambiguous with asplenia, there is abnormal arrangement of the organs and major blood vessels due to right atrial isomerism with congenital heart disease occurring in 50%–100% of cases which usually prompts early diagnosis of the syndrome, however, in our case, echocardiogram was normal. Our case was challenging given the fact that the patient's volvulus presented in a way mimicking DKA as well as being the first presentation of her heterotaxy syndrome. We emphasize on the importance of considering volvulus in the differential diagnosis of DKA as early diagnosis and intervention improves outcomes.