A Rare Cause of Abdominal Pain.

CASE: A 54 year old woman with hypothyroidism presented with right flank pain that began acutely one week prior to presentation. She was told initially she had a urinary tract infection and treatment resulted in mild symptomatic improvement. The pain returned and she presented to another Emergency Department (ED); and was told the pain was due to constipation. She returned to the ED the next day when her pain worsened and her labs were notable for WBC of 19,000/uL, BUN/Cr of 28/0.75 mg/dL, AST of 31 U/L, ALT of 92 U/L and total bilirubin of 0.6 mg/dL. RUQ ultrasound was notable for dilation of the common bile duct. Given concern for choledocholithiasis, she was started on cefepime and metronidazole. MRCP demonstrated a distended gallbladder without stones and a small amount of pericholecystic fluid. Also noted were two areas of increased signal in the right kidney, concerning for neoplasia or infarction. Contrasted abdominal Computed tomography showed a moderate size area of hypodensity, consistent with renal infarct. Workup for embolic source of the infarction was unrevealing. Renal artery angiogram demonstrated a spontaneous dissection of the superior branch of the right renal artery. PCI was not performed due to risk of jeopardizing the other vessels and so she was managed medically with rivaroxaban along with hydrochlorothiazide and metoprolol succinate to keep her systolic blood pressure below 140 mmHg. The morning after the procedure, the patient told the treatment team that her grandson liked to jump from a height and she would catch him on her right side. This was felt to be a likely etiology of her spontaneous dissection. At the time of discharge, her pain was improved and repeat angiogram performed eight weeks later noted healing of the dissection.

DISCUSSION: Spontaneous renal artery dissection is a rare cause of abdominal pain and often presents a diagnostic and therapeutic challenge. This case highlights the importance of considering alternate etiologies of localized abdominal pain when other common pathologies have been excluded.