At the start of the Monkeypox (MPX) outbreak in New York City in June 2022, the Centers for Disease Control provided materials to validate the MPX test to only five major commercial reference labs. Montefiore providers waited a week to 10 days to receive the test results. The slow turnaround time delayed time-sensitive patient care and increased the likelihood of disease transmission.
To speed up the processing time, the department of Pathology's Virology lab set out to develop an in-house test. Led by D. Yitzchak Goldstein, MD, a self-described 'data wonk' with a passion for advanced molecular diagnostics, the lab worked closely with its Montefiore infectious diseases partners Inessa Gendlina, MD, PhD, and Greg Weston, MD.
Dr. Goldstein, Director of the Molecular Pathology Laboratory and Virology Laboratory and Assistant Professor of Pathology at Montefiore Einstein, explains what providers need to know about MPX testing, the technology, and the lab's newest testing platforms. Dr. Gendlina describes how the in-house Monkeypox test has impacted patient care and streamlined the process for providers.
Once the lab receives a MPX specimen, what's the technology? How sensitive is the test?
YG: The dual target PCR assay can detect DNA of non-Variola orthopoxviruses (NVOs) (vaccinia virus and monkeypox virus) and the West African clade of the monkeypox virus DNA. It was essential to have multiple targets to improve sensitivity, in case new variants of the monkeypox virus developed.
In-house testing uses a control to ensure that the reaction works correctly and that the lesion swab sample is of sufficient quality. While other labs may use a control covering the reaction, we decided a cellular control, informing about the adequacy of collection, provided the most accurate results for our patients.
How has the collection of monkeypox specimens changed since bringing the test in-house?
YG: We converted the specimen collection to a wet swab in a viral transport medium. This method allows us to use a single tube to collect the specimen for MPX as well as for herpes and varicella and perform all the necessary tests on these lesions, which can present similarly. Clinicians no longer have to deal with multiple collection tubes going to different laboratories avoiding mismatched labels.
What does an 'invalid' MPX test mean?
YG: In a nutshell, an invalid test means that while we didn't detect either of the targets, we also didn't have the cellular material necessary to provide a valid result which may indicate a suboptimal collection. While swabbing monkeypox lesions can be quite painful, we encourage clinicians to try their best to ensure adequate cellularity to get a valid result.
Has the in-house testing improved your ability to treat patients?
IG: In-house testing has significantly improved our patient care. We frequently get same-day results and can initiate therapy immediately, dramatically impacting overall patient well-being. Waiting for MPX test results is very stressful for patients; a rapid turnaround can ease the burden. Knowing the testing results for hospitalized patients also improves throughput and infection control practices and reduces staff and patient exposure.
Designing the in-house MPX was a great accomplishment. What was most challenging?
YG: It's important to realize that until mid-October, there were no commercially available reagents for monkeypox testing. This testing was designed and validated from the ground up using the expertise and coordination of the pathology department and achieving NYS approval in record time. The lab had to have specialty reagents synthesized and only received the materials to validate the tests at the end of July.
MPX results went from taking about five days to most often having results available the next day. As with the first in-house COVID PCR test, which we also designed, the faster turnaround time demonstrates the talent, teamwork, drive, and organization of the pathology department when resourced to succeed.
How else is the Virology Lab using innovative diagnostic testing?
YG: We recently updated our diagnostic tests for vaginosis and vaginitis from an old slide-based Gram stain evaluation to a rapid modern molecular test that evaluates the differential quantities of good and bad bacteria. We're also now using molecular testing for candida instead of simply looking for yeast on a slide.
The lab has also updated its testing platform for Cytomegalovirus (CMV) to a random-access instrument, which has decreased the turnaround time. We'll soon be bringing Epstein Barr Virus (EBV) testing in-house.
What should providers know about working with Pathology?
YG: If you have a question, ask us. One of the most significant advantages of performing this testing in-house is that providers can pick up the phone and call the laboratory; we're here to help. We want to make sure that we're offering a valuable service. We view ourselves as partners in the patient's clinical care. The partnership with the clinical teams has always benefited everyone involved. We hope that coordination continues.
To contact the pathology labs, dial 718-920-4695 and select option 3 for customer service.
Posted on: Thursday, November 17, 2022