Clinical analysis of contributors to the delayed gallbladder opacification following the use of water-soluble contrast medium

Gallbladder and Small Intestinal Luminal Opacification by Vicarious Contrast Medium Excretion Can be Observed on Delayed Computed Tomography in Healthy Dogs

Vicarious excretion is a nonrenal pathway of excretion for intravenously injected iodinated contrast media, with a limited understanding of its influencing factors and imaging features. In this prospective pilot study, gallbladder opacification (GBO) and small intestinal luminal opacification (SILO) were assessed to identify vicarious excretion patterns following intravenous contrast media administration for CT in clinically healthy dogs. Eight beagles were studied using a crossover method, divided into fed and fasted groups. The fed group was fed at 5 and 13 h after the first CT scan, while the fasted group was fed only at 13 h. Noncontrast and postcontrast CT scans were performed at 90 s, 10 min, 1 h, 4 h, 12 h, and 24 h after iohexol injection. The GBO was subjectively scored from grade 0 to 5 based on the attenuation value and area of opacification. The SILO was evaluated subjectively based on contrast intensity (weak or marked) and distribution. The GBO was observed from 1 h after contrast injection. Significant differences were noted in median GBO scores within the groups at 4, 12, and 24 h on Friedman's test followed by the post hoc Wilcoxon signed-rank test. The scores were significantly higher in the fasted group at 12 h on the Wilcoxon signed-rank test. The SILO occurred 10 min after contrast administration, with various distributions. In conclusion, GBO and SILO can be observed during delayed CT phases, and fasting increases the intensity and duration of GBO in clinically healthy dogs. These findings should not be interpreted as pathological changes.

Cholecystitis and Cholangitis during Continuous Renal Replacement Therapy in a Patient with Retroperitoneal Hemorrhage Requiring Large Amounts of Contrast Medium for the Assessment and Intervention

Intravenous use of contrast medium (CM), which may cause kidney dysfunction, is admissible for hemodialysis patients because of the efficient removal by hemodialysis. We herein report a 61-year-old woman on hemodialysis who suffered from cholecystitis and cholangitis after large-volume CM administration during continuous renal replacement therapy. After catheter ablation, she developed life-threatening retroperitoneal hemorrhage, which led to the use of 500 mL CM for 5 consecutive days. It should be kept in mind that excessive vicarious CM excretion in the biliary system may become a predisposing factor of cholecystitis and cholangitis in patients who frequently undergo radiological interventions and imaging.

Octreotide-induced acute life-threatening gallstones after vicarious contrast medium excretion: A case report

BACKGROUND

Octreotide is widely used for the treatment of acromegaly, neuroendocrine tumors, and secretory diarrhea. However, long-term octreotide treatment can increase the incidence of gallstones. Vicarious contrast medium excretion (VCME) through the hepatobiliary system is well known. However, few studies have reported octreotide-induced acute gallstones following VCME.

CASE SUMMARY

A 69-year-old man presented with left lower back pain and hematuria caused by a fall. The patient had a history of polycystic kidney disease. VCME occurred following renal artery embolization for a ruptured polycystic kidney. After 5 d of treatment with octreotide, the patient developed acute gallstones and intrahepatic cholestasis which further induced pancreatitis and cholangitis. He was discharged after hemodialysis, antibiotics, and supportive treatments.

CONCLUSION

For patients with a high-risk of VCME, octreotide should be cautiously administered and carefully monitored.

A young woman with right upper quadrant pain

Patients with right upper quadrant pain are commonly encountered in the emergency department. The causes of right upper quadrant range from infection or inflammation to malignancy. Thus, prompt and accurate diagnoses are essential in the emergency department. However, vicarious excretion of contrast media via the gallbladder, presenting as right upper quadrant pain, has been rarely reported and is not well known. The present case is instructive because gallbladder opacification is often considered a pathologic condition in patients with right upper quadrant pain. Although vicarious excretion via the gallbladder is uncommon in patients with right upper quadrant pain, inaccurate or delayed diagnoses may prolong hospitalization and increase medical costs due to unnecessary and invasive diagnostic procedures.