November 21, 2019
4 min read

CDC updates guidance on vaping-associated lung injury in wake of flu season

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As the outbreak of electronic cigarette- or vaping-associated lung injuries, or EVALI, continues, CDC has updated its interim guidance to help clinicians diagnose and treat patients with the condition in light of the approaching 2019-2020 influenza season.

As of Nov. 20, 2,290 cases of EVALI have been reported to CDC from 49 states, the District of Columbia, Puerto Rico and the U.S. Virgin Islands. These cases included 47 EVALI-associated deaths in 25 states and the District of Columbia.

The new recommendations, published in MMWR, are an update to the interim clinical guidance released Oct. 11.

“Because patients with EVALI can experience symptoms similar to those associated with influenza or other respiratory infections (eg, fever, cough, headache, myalgias or fatigue), it might be difficult to differentiate EVALI from influenza or community-acquired pneumonia on initial assessment,” the researchers wrote. “This report summarizes recommendations for health care providers managing patients with suspected or known EVALI when respiratory infections such as influenza are more prevalent in the community than they have been in recent months.”

Important recommendations

The new guidance contains several key recommendations.

  • When evaluating patients with respiratory, gastrointestinal or constitutional symptoms such as fever, chills or weight loss, health care providers should ask about the use of e-cigarette or vaping products in a confidential and nonjudgmental manner. They should also ask about the types of products used, such as those containing tetrahydrocannabinol (THC) and from where the products were obtained.
  • Health care providers should assess vital signs and pulse oximetry as well as obtain chest imaging, as clinically indicated.
  • Health care providers should consider whether a patient can be managed on an outpatient basis, as not all patients with EVALI require hospitalization. Outpatient management may be possible if the patient has normal oxygen saturation levels, no respiratory distress, no comorbidities that might compromise pulmonary reserve, reliable access to care, strong social support systems and should be able to ensure follow-up within 24 to 48 hours of the initial evaluation or if symptoms worsen.
  • Influenza testing is strongly encouraged and treatment with empiric antimicrobials, including antivirals, should be considered if clinically indicated.
  • Corticosteroids might be helpful for treating EVALI, but health care providers should be aware that the treatment has not been well studied among outpatients and could potentially worsen respiratory infections.
  • Consultation with a variety of specialists, including those from infectious disease, pulmonary, psychiatry and addiction medicine, should be considered and treatment strategies such as behavioral counseling are recommended to help patients discontinue use of e-cigarette or vaping products.
  • Follow-up after discharge for EVALI should be conducted within 1 to 2 weeks.

Additionally, as CDC has emphasized since the beginning of the outbreak, people should consider refraining from using e-cigarette or vaping products until the cause of the outbreak has been determined. Because many patients with EVALI have reported use of THC-containing products, CDC also recommends against their use, especially when the products have been obtained from informal sources, such friends, dealers or off the street.

Although vitamin E acetate has been implicated as a possible cause of EVALI, CDC emphasizes that it has not isolated a specific contributor and multiple substances may be responsible for the outbreak. Therefore, CDC states that people should not modify or add substances to e-cigarette or vaping products.

Characteristics of nonhospitalized patients

A second report published in MMWR discussed details of hospitalized and nonhospitalized patients with EVALI. The case report information derives from data collected through Nov. 5 and includes information on 2,016 patients with EVALI, including 1,906 who were hospitalized and 110 who were not.

Among hospitalized and nonhospitalized patients, most were men (68% vs. 65%, respectively; P = .4), white (79% vs. 82%, respectively; P = .5) and younger than 35 years (78% vs. 74%, respectively; P = .3). Use of THC-containing products (93% vs. 84%, respectively; P = .9) and nicotine-containing products (60% vs. 73%, respectively; P = .06) were also similar between hospitalized and nonhospitalized patients.

Notably, however, more hospitalized patients than nonhospitalized patients were deemed confirmed rather than probable cases of EVALI (55% vs. 12%; P < .01).

At the initial outpatient visits for nonhospitalized patients with EVALI, most reported experiencing respiratory symptoms (85%), gastrointestinal symptoms (57%) and constitutional symptoms (76%), with only 9% reporting just one type of symptom. Thirty percent of patients also had oxygen saturation less than 95% and 40% had tachycardia.

Furthermore, 82% of the 34 patients with reported results for initial chest radiographs had abnormal findings and 76% had bilateral findings. All 28 patients with reported results for chest CT had abnormal findings, with all but one having bilateral findings. Thirty-eight percent of 15 patients with both a chest radiograph and a chest CT had an initial normal chest radiograph but an abnormal chest CT and 63% had abnormal findings on both chest radiograph and chest CT.


“Given the similarity between hospitalized and nonhospitalized EVALI patients, the potential for large numbers of respiratory infections during the 2019-20 influenza season, and the potential difficulty in distinguishing EVALI from respiratory infections, CDC will no longer collect national data on nonhospitalized EVALI patients,” the researchers wrote. – by Melissa Foster

Disclosures: The authors report no relevant financial disclosures.

Editor's note: This article was updated on Nov. 22 to include new information on the number of EVALI cases and EVALI-associated deaths.