As a gastroenterologist at the forefront of patient care, you may be facing challenges diagnosing and treating complex gastrointestinal (GI) and/or genitourinary (GU) conditions. From inflammatory bowel disease (IBD) to colorectal cancer, GI/GU conditions rank among the nation’s most serious health challenges, contributing to significant discomfort, treatment costs, lost work hours, and even mortality.
From screening and diagnosis to treatment and monitoring, Quest offers a vast gastroenterology testing portfolio that provides the reliable answers you and your patients deserve across the full care continuum, at every stage. Our peer-vetted, clinically relevant testing helps gastroenterologists provide differential diagnoses in even the most complex cases.
Inflammatory bowel diseases (IBD) includes Crohn disease (CD) and ulcerative colitis (UC).
In the US
Because CD and UC manifest differently in digestive tissue and have different prognoses and treatments, a differential diagnosis is paramount.
It is estimated that celiac disease affects affect 1 in 100 people worldwide, but only about 30% are properly diagnosed.4
For individuals with celiac disease, testing is one of the first steps to diagnosis and ongoing treatment monitoring over time to detect associated conditions and nutritional deficiencies.
Each year in the US, acute infectious diarrhea accounts for
For certain infections, an organism-specific diagnosis is important to guiding clinical management.5
Quest has made molecular testing more accessible with a qualitative PCR panel that can simultaneously, from a single specimen, detect 9 of the most common pathogens associated with infectious diarrhea.
More than 1 in 3 Americans are affected by Helicobacter pylori (H pylori).6 If undetected or left untreated, the infection can cause chronic, progressive damage to the gastric mucosa and can result in life-threatening outcomes, such as peptic ulcers or gastric cancer.
Quest offers comprehensive H pylori infection testing aligned with American College of Gastroenterology (ACG) guidelines,7 including urea breath testing (UBT) and stool antigen testing.
High rates of obesity, insulin resistance, and metabolic syndrome have led to an increase in metabolic dysfunction–associated steatotic liver disease (MASLD).a This can progress to metabolic dysfunction–associated steatohepatitis (MASH),a putting these patients at risk for cardiovascular disease and end-stage liver disease.
Because MASLD can progress with nonspecific symptoms, patients may not know they have it. The cardiometabolic test portfolio from Quest can provide early identification of patients with MASLD or MASH, as well as insights on disease progression.
a MASLD was formerly known as nonalcoholic fatty liver disease (NAFLD), and MASH was formerly referred to as nonalcoholic steatohepatitis (NASH).
Many at-risk patient populations are susceptible to chronic infections which, left untreated, can cause serious health problems including liver failure.
Screening
Diagnosis
We are a leading provider of genitourinary and gastroenterology pathology services:
Prognosis
Our advanced testing helps guide patient treatment decisions:
b Clinical guidelines recommend PSA as a front-line screening test for prostate cancer in men.
References
1. CDC. IBD facts and stats. June 21, 2024. Accessed November 4, 2024. https://www.cdc.gov/inflammatory-bowel-disease/php/facts-stats/index.html
2. Lynch WD, Hsu R. Ulcerative colitis. In: StatPearls [Internet]. StatPearls Publishing; January 2024. Updated June 5, 2023. Accessed November 15, 2024. https://www.ncbi.nlm.nih.gov/books/NBK459282/
3. Aniwan S, Park SH, Loftus EV Jr. Epidemiology, natural history, and risk stratification of Crohn’s disease. Gastroenterol Clin North Am. 2017;46:463-480. doi:10.1016/j.gtc.2017.05.003
4. Celiac Disease Foundation. What is celiac disease? Accessed October 12, 2024. https://celiac.org/about-celiac-disease/what-is-celiac-disease/
5. Shane AL, Mody RK, Crump JA, et al. 2017 Infectious Diseases Society of America clinical practice guidelines for the diagnosis and management of infectious diarrhea. Clin Infect Dis. 2017;65(12):1963-73. doi:10.1093/cid/cix669
6. Aldhaleei W, Wallace M, Harris D, et al. Helicobacter pylori: a concise review of the latest treatments against an old foe. Cleve Clin J Med. 2024:91(8):481-487. doi:10.3949/ccjm.91a.24031
7. Chey WD, Howden CW, Moss SF, et al. ACG clinical guideline: treatment of Helicobacter pylori infection. Am J Gastroenterol. 2024;119(9):1730-1753. doi:10.14309/ajg.0000000000002968
8. Olaru I, Beliz Meier M, Mirzayev F, et al. Global prevalence of hepatitis B or hepatitis C infection among patients with tuberculosis disease: systematic review and meta-analysis. EClinicalMedicine. 2023;58:101938. doi:10.1016/j.eclinm.2023.101938
9. CDC. Reported tuberculosis in the United States, 2022. Updated November 15, 2023. Accessed June 25, 2024. https://www.cdc.gov/tb/statistics/reports/2022/table17.htm
10. National Institutes of Health. HIV and opportunistic infections, coinfections, and conditions. Accessed February 24, 2025. https://hivinfo.nih.gov/understanding-hiv/fact-sheets/hiv-and-hepatitis-c
11. Hellard M, Sacks-Davis R, Gold J. Hepatitis C treatment for injection drug users: a review of the available evidence. Clin lnfect Dis. 2009;49(4):561-573. doi:10.1086/600304
12. Suryaprasad AG, White JZ, Xu F, et al. Emerging epidemic of hepatitis C virus infections among young nonurban persons who inject drugs in the United States, 2006-2012. Clin Infect Dis. 2014;59(10):1411-1419. doi:10.1093/cid/ciu643
13. Shayan SJ, Nazari R, Kiwanuka F. Prevalance of HIV and HCV among injecting drug users in three selected WHO-EMRO countries: a meta-analysis. Harm Reduct J. 2021;18(1):59. doi:10.1186/s12954-021-00505-4
14. Carney T, Rooney JA, Neiman N, et al. Transmission of tuberculosis among illicit drug use linkages (total): a cross-sectional observational study protocol using respondent driven sampling. PLoS One. 2022:17(2):e0262440. doi:10.1371/journal.pone.0262440
15. Magiorkinis G, Sypsa V, Magiorkinis E, et al. Integrating phylodynamics and epidemiology to estimate transmission diversity in viral epidemics. PLoS Comput Biol. 2013;9(1):e1002876. doi:10.1371/journal.pcbi.1002876
16. American Cancer Society. Key statistics for prostate cancer. Updated January 16, 2025. Accessed February 21, 2025. https://www.cancer.org/cancer/types/prostate-cancer/about/key-statistics.html
17. American Cancer Society. Can colorectal polyps and cancer be found early? January 29, 2024. Accessed November 8, 2024. https://www.cancer.org/cancer/types/colon-rectal-cancer/detection-diagnosis-staging/detection.html
18. NIH National Cancer Institute. Genetic testing for inherited cancer risk. Updated April 18, 2024. Accessed February 21, 2025. https://www.cancer.gov/about-cancer/causes-prevention/genetics/genetic-testing-fact-sheet
About our tests
Inflammatory bowel disease: Laboratory support for diagnosis and management
Celiac Disease Comprehensive Panel with Gliadin Antibody (IgG)
ACG clinical guideline: Treatment of Helicobacter pylori infection
InSure® ONE™: Helping your patients with easy-to-use, in-home colorectal cancer screening
Our Test Directory includes more than 3,500 tests ranging from routine screening to highly specialized testing.
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