Dr. Edgar H. Tan, a consistent honor student graduated Bachelor of Science major in Biology cum laude from Silliman University in 1982. A Faculty Silver Medal Awardee and graduated cum laude when he earned his Medical Degree from Cebu Doctors' College of Medicine in April of 1986.

He spent one year of post graduate internship at the prestigious Philippine General Hospital from May 1, 1986 to April 30, 1987 and subsequently passed his Philippine Medical Licensure Exam rank #15 in August of 1987. He pursued further training in Internal Medicine from 1989-1993 under the New York Medical College Program where he served as the Administrative Chief Medical Resident for one year. He subsequently did his Fellowship Training in Clinical/Invasive Cardiology under the consortium of Metropolitan & New York Medical College Program from 1993-1996. After his medical training in New York he practiced Internal Medicine/Invasive Cardiology in the State of South Carolina from 1996-1997 with privileges at Marlboro Park Hospital Bennettsville SC & McLeod Regional Medical Center in Florence SC. He holds an active medical license in the State of South Carolina from 1996 up to the present. He decided to come back to Cebu and practice his profession starting February 1998. His foresight at keeping his US medical license active inspite of practicing medicine outside the US has come handy for US expats currently in the Philippines wanting medical care recognized by US HMO's.

Dr. Tan is board certified by the American Board of Internal Medicine, American Board of Cardiovascular Disease and Philippine College of Physicians. He is also trained and certified in the field of Nuclear Cardiology. He is a Fellow of the American College of Physicians, American College of Cardiology and Philippine College of Physicians. His extensive background comes handy by making available the highest standard of US quality medical care right in the heart of Cebu City.

He is affiliated with Cebu Doctors' University Hospital, where he is currently the Section Head of Cardiology Department. He is also affiliated with UCMed and Perpetual Succour Hospital. His practice includes General Internal Medicine & Adult Clinical/Interventional Cardiology. He has admitting privileges at the University of Cebu Medical Center, Cebu Doctors' University Hospital & Perpetual Succour Hospital.

His office is located at Cebu Doctors' University Hospital Medical Arts Building 1, Suite 203-B, OsmeƱa Blvd. Cebu City Philippines. His office hours are 9am-12pm Mon-Sat. and 2pm to 5pm except Wed. and Sat. Tel: (032) 412-5136.

Email:EdgarTan62@yahoo.com or EdgarTanMD@gmail.com

Tuesday, November 03, 2020

Covid-19 " Cytokine Storm " a Misnomer?

When Covid-19 came into this world, we soon realized that the havoc wreaked by such a novel virus is due to the accumulation of inflammatory cytokines of which medical experts describe as " Cytokine Storm". This remains to be the prevailing theory up to this time and our local experience echos what has been observed.   The presence of a persistent and unrelenting rise in measurable inflammatory cytokines among Covid-19 infected patients that is responsible for determining the overall clinical outcome. 

After having seen quite a few Covid-19 infected patients, my view has changed. I look at “cytokine storm” as a misnomer because it seems to imply a sudden unpredictable surge in inflammatory levels. I prefer to describe Covid-19 infection as  "an inflammatory condition associated with a progressive cytokine build-up".  Our body compensates very well early on as these cytokines start building up but,  it comes to a point when the body’s compensatory mechanisms start to fail and clinically failure comes in two phases:

1st Phase is Respiratory:  As the name implies, this is characterized by a progressive increase in patients' need for oxygenation along with lung infiltrates on the CXR that could progress and lead to intubation on some select patients.  One important observation is that these infiltrates are often inversely proportional  to the degree of hypoxemia suggesting that there is more to it that what meets the eye when you look at the chest X-ray. Simply put, the degree of hypoxemia more often than not is disproportionately worst when compared to the degree and extent of pulmonary infiltrates seen on the chest X-ray.

2nd Phase is Autonomic Collapse:  This is usually a terminal event associated with hyperinflammatory cytokines with the patient having intractable hypotension with multiorgan failure & eventual death. This is a very common terminal event that we see & call as cytokine storm.
 
In the most recent randomized clinical trial from Harvard, by John H. Stone et. al. published in the NEJM Oct. 21, 2020 "Efficacy of Tocilizumab in Patients Hospitalized with Covid-19." (https://www.nejm.org/doi/full/10.1056/NEJMoa2028836) on patients with severe respiratory distress syndrome, the use of Tocilizumab did not seem to confer any benefit in terms of preventing intubation. Furthermore patients randomized on that study had a very wide range of baseline inflammatory levels suggesting that patients have different thresholds with regard to when they show signs of clinical decompensation. This observation suggests that if we try to seek the answer and predict decompensation by looking at levels of inflammatory cytokines, we  might not find one. It reenforces my belief that the presence of known comorbidities like obesity, diabetes, heart disease (CAD and CHF), COPD play  a greater role in determining the overall clinical course and outcome of Covid-19 infected patients. These highly variable inflammatory cytokine levels at baseline on recruited patients is in keeping with my proposition that best describes Covid-19 infection as a condition characterized by  “progressive cytokine build-up” alongside clinical deterioration determined largely by the presence or absence of comorbidities as mentioned earlier.

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