key: cord-0043735-dtpu6qde
authors: Mago, Sheena; Young, Patrick E.; Tadros, Micheal
title: Positive FIT or Cologuard in the Era of COVID-19 Pandemic
date: 2020-05-23
journal: Gastroenterology
DOI: 10.1053/j.gastro.2020.04.046
sha: fb6f90c9375ad0f235b4f7d20e457845f7538348
doc_id: 43735
cord_uid: dtpu6qde

nan

To the Editor, We have encountered a few patients with positive FIT (fecal immunochemical test) and multitarget DNA/FIT tests (MT-DNA/FIT) in midst of the COVID-19 pandemic which have required us to have detailed discussions with our patients and balance the pros and cons of proceeding with colonoscopy now verses postponing it for possibly more than 6 weeks, until the end of this crisis.

The COVID-19 pandemic has caused drastic changes amongst healthcare facilities around the world, leaving routine healthcare follow-ups and screenings as a distant priority. To date there are over 1 million cases worldwide with over 29% of cases in the USA [1] . This disease gained its infamy due to its well-known symptoms of cough, shortness of breath, and fevers [2] .

As the incidence of cases worldwide continue to increase, a certain percentage of patients have been noted to have gastrointestinal (GI) symptoms -such as nausea and diarrhea -in conjunction with or in lieu of the other more common respiratory symptoms [2] . In a retrospective study of 850 hospitalized COVID-19 positive patients done by Han et al. in February 2020, those exclusively with GI symptoms were compared to patients with only respiratory symptoms or a combination [3] . It was seen that patients with only GI symptoms had delayed diagnosis, longer time to viral clearance, and were more likely have stool positive for the viral RNA in comparison to those patients with solely respiratory symptoms [2] . Given the concern for this deadly virus to transmit via droplets/fecal shedding, it poses a significant risk during GI procedures [3] . There is also concern as a significant number of patients are asymptomatic viral carriers. Doing GI procedures on these seemingly healthy patients poses an unknown threat [3] .

The unified guidelines for endoscopic procedures were published on March 31 st , 2020 by multiple gastroenterological professional societies [3] . American Gastroenterological Association also published their own 'Rapid Recommendations for Gastrointestinal Procedures during the COVID-19 Pandemic' on April 1 st [4] . Based on these guidelines, it is recommended that all elective procedures be delayed, such as screening and surveillance colonoscopy in asymptomatic patients [4] . It is also now recommended to use a N95 and full personal protective equipment (PPE) when doing colonoscopies [4] .

While it is clearly reasonable to delay screening and surveillance colonoscopies in asymptomatic patients, what about patients with a positive FIT or MT-DNA/FIT test? What are the risks versus benefits of prolonged delay for follow-up colonoscopy [4] ? For asymptomatic patients with a positive FIT or MT-DNA/FIT test a colonoscopy is classified as a non-urgent procedure and for most cases is acceptable to delay by at least 8 weeks [4] .

Colorectal carcinoma (CRC) is the third most commonly diagnosed form of cancer, however the evolution of precancerous lesions are usually a relatively slow process and early detection is essential in efficacious outcomes [5] . Colonoscopy has been the gold-standard for identifying pre-malignant and malignant colonic lesions, however FIT and MT-DNA/FIT can also be used for the detection of colon cancer/adenomas [5] . When these tests result as 'positive' it is followed-up with an endoscopic procedure for direct visualization of the colon [5] .

Overall, MT-DNA/FIT and FIT testing for the detection of CRC have a sensitivity of 92.3% and 73.8% respectively, whereas for advanced adenoma (AA) it is 42.4% and 23.8% respectively [6] .

The specificity of MT-DNA/FIT (86.6%) and FIT (94.9%) are low for patients CRC or AA [6] .

When a positive MT-DNA/FIT test is encountered, 3.72% of patients have CRC and 19.86% have AA [6] . With positive FIT tests, 2.9%-7.8% have CRC and 33.9%-54% have AA [7] . The false positive rates for MT-DNA/FIT (13.4%) and FIT ( 5.1%) are associated with peptic ulcer disease and non-steroidal anti-inflammatory drug usage [6, 8] . These numbers are important when discussing with patients for adequate shared decision-making. It is important to take into account patient's prior colonoscopies, personal/familial risk factors, and evidence of any 'redflag symptoms' -such as significant weight/appetite loss, rectal bleeding, or abdominal pain -to decide the necessity of prompt endoscopy.

Based on this data (the slow progress from adenoma to CRC, relatively high percentage of false positive and approximate 5% of colon cancer found for a positive FIT or MT-DNA/FIT test) we agree that it would be judicious to delay endoscopic screening for asymptomatic individuals with a positive FIT or MT-DNA/FIT test to minimize the risk of disease transmission to medical providers, risk of infection to the patients themselves, and to save essential PPE for those on the frontline who need them the most.

World Health Organization. Coronavirus disease (COVID-19) Pandemic

American Society for Gastrointestinal Endoscopy. Gastroenterology Professional Society Guidance on Endoscopic Procedures During the COVID-19 Pandemic

Summary of Safety and Effectiveness Data