Technical notes on high-frequency ultrasound duodenography and colonography imaging of giardial lesions

Abstract

Background: Worldwide G. lamblia is the third most common agent of diarrheal disease with over 300 million cases annually. Simple technical notes for clinicians are presented on use of high-frequency ultrasound imaging for duodenography and colonography in patients with Giardia lamblia infection. Methods: Ultrasound images were obtained from 100 consecutive patients with symptomatic giardiasis and 40 healthy controls. High-frequency annular array transducer of 7.5 MHz was used to obtain B-mode ultrasound grayscale and color images of the duodenum and colon with and without water contrast. The diagnosis of G. lamblia was based on clinical presentation, serial stool microscopy, and finding of flagellates in duodenal aspirates. Results: We demonstrated normal duodenum and colon echoanatomy in control subjects. In patients with giardiasis, the lesions of the duodenum and colon were associated with increased dimensions and wall thickness compared to healthy controls (P < 0.05). The ultrasound features of giardial lesions were characterized by increased wall echogenicity, flattening or loss of duodenal folds and/or colonic haustration, hyperechoic floating foci demonstrating chaotic motility, increased perilesional tissue echogenicity, and altered colonic peristalsis. Conclusion: In conclusion, high-frequency B-mode ultrasound imaging with and without water contrast demonstrated the details of duodenal and colonic echoanatomy in normal subjects and patients with giardiasis. The technique could be applied in the clinical setting of rural practitioners.