Prevalence and Predictors of Giardia in the United States

• Published in: Digestive diseases and sciences Vol. 62; no. 2; pp. 432 - 440
• Main Authors: Zylberberg, Haley M., Green, Peter H. R., Turner, Kevin O., Genta, Robert M., Lebwohl, Benjamin
• Format: Journal Article
• Language: English
• Published: New York Springer US 01.02.2017; Springer; Springer Nature B.V
• Subjects: Adolescent; Adult; Age Factors; Analysis; Biochemistry; Biopsy; Coinfection - epidemiology; Cross-Sectional Studies; Development and progression; Diarrhea; Duodenum - pathology; Endoscopy; Ethnic Groups - statistics & numerical data; Female; Gastritis, Atrophic - epidemiology; Gastroenterology; Giardia lamblia; Giardiasis - epidemiology; Giardiasis - pathology; Health aspects; Helicobacter Infections - epidemiology; Helicobacter pylori; Hepatology; Humans; Male; Medical laboratories; Medical research; Medicine; Medicine & Public Health; Medicine, Experimental; Middle Aged; Multivariate Analysis; Oncology; Original Article; Prevalence; Retrospective Studies; Risk Factors; Rural Population; Seasons; Sex Factors; Southeastern United States - epidemiology; Stomach - pathology; Transplant Surgery; United States - epidemiology; Urban Population; Young Adult; Southeastern United States; United States; Diarrhea; Giardia; Endoscopy; Epidemiology
• ISSN: 0163-2116; 1573-2568
• DOI: 10.1007/s10620-016-4447-0

Background Infection with Giardia lamblia is a common cause of diarrheal disease in the developing and industrialized world. Aims We aimed to assess the prevalence of giardiasis in the United States (US) among patients with duodenal biopsies, investigating demographic and clinical factors associated with this condition. Methods We conducted a cross-sectional study of patients with duodenal biopsies submitted to a national pathology laboratory between January 2, 2008, and December 31, 2015. The prevalence of giardiasis was calculated and categorized by the following patient sociodemographic and clinical data: age, sex, ethnicity, endoscopy indication, season, year, urban–rural setting, region, and presence of H. pylori and atrophic gastritis. Results Among all patients ( n  = 432,813), the mean age was 52.2 years. The prevalence of giardiasis was 0.11%. Patients with giardiasis were more likely to be male (57.8 vs. 34.1%, p  < 0.0001). Among patients who had a gastric biopsy ( n  = 363,788), those with giardiasis were more likely to be colonized with H. pylori (25.7 vs. 9.4%, p  < 0.0001). There was no statistically significant association with age, endoscopy indication, urban–rural setting, ethnicity, season, or the presence of atrophic gastritis. On multivariate analysis, male sex, Southern region, and the presence of H. pylori were independently associated with giardiasis. Conclusions To our knowledge, this is the largest study to date to assess predictors of giardiasis in the US. We found that male sex, being colonized with H. pylori, and residing in the Southern US are independently associated with giardiasis infection.