Background: E-cigarette or vaping-associated lung injury (EVALI) was first reported in 2019 in the United States (1-2). Reported lung findings in this disease include acute respiratory distress syndrome, acute eosinophilic pneumonia, hypersensitivity pneumonia, and giant cell interstitial pneumonitis (3-5). Considering the additional reports of diffuse alveolar hemorrhage and hemoptysis (6-11), we obtained coagulation studies prior to investigatory bronchoscopy and noted increased clotting time in the extrinsic coagulation pathway which caused a procedure delay. Clotting time improved with administration of vitamin K and steroids. The present study aimed to investigate whether this finding was an isolated phenomenon or a common characteristic in this patient population. Our study also aimed to report other clinical and laboratory findings in pediatric EVALI.

Methods: IRB approval was obtained to examine patient data for those admitted to the pediatric floor and pediatric intensive care units from January 2019 to October 2020. Patient population was selected using diagnosis codes J68.8 and U07.0; only patients >12 years old were included. Considering that these vaping-related codes did not exist until late 2019, we cross-referenced codes for pneumonia and pulmonary complications with marijuana or nicotine abuse codes and also included patients with positive urine drug screens for THC. Individual charts were reviewed by three physicians for clinical findings consistent with Confirmed or Probable EVALI according to the CDC case definition published August 2019 (12).

Results: Fifty-five patients met the coding criteria in our EMR database. Twenty-nine patients met criteria for Confirmed (n=22) or Probable (n=7) EVALI. Average age at admission was 16.1 ± 1.1 years and 20 of the patients were male. Vaping substance included Nicotine (n=1), THC (n=17), Both (n=8), or Unknown (n=3). Coagulation studies were found for ten patients with confirmed EVALI and one with probable EVALI. Aggregate data showed PT 18.6 ± 3.8 [Ref 10.5-12.6 sec], PTT 32.8 ± 7.2 [25.1-36.5 sec], INR 1.61 ± 0.3 [0.91-1.09], Platelets 346 ± 102.8 [150-400 k/uL], Fibrinogen 807 ± 176.8 [191-492 mg/dL] and D-dimer 1416 ± 1062 [0-500 ng/mL]. Liver enzymes and albumin were within normal limits. Vitamin K was administered to 8 of 10 patients, whereas steroids were administered to all 10 patients. Clotting time normalized in patients who had follow up labs performed within 48-72 hours after intervention. Seven patients underwent in-hospital pulmonary function testing (PFTs) which showed mild obstruction with decreased diffusion capacity of carbon monoxide. Eleven patients had post treatment PFTs with normal function. Other significant findings included WBC 14.5 ± 3.7 [5.24-9.74 k/uL] without eosinophilia, CRP 26.6 ± 11.5 [<1.0 mg/dL], and ESR 61.7 ± 25.2 [0-15 mm/hr].

Conclusions: Patients diagnosed with EVALI showed a significant increase in clotting time in the extrinsic pathway which improves after vitamin K and steroid supplementation. Our sample size is small but considering the findings of alveolar hemorrhage and hemoptysis in this population, we suggest that precautionary coagulation studies should be checked especially if patients are undergoing an invasive procedure. To date, this has not been published in the literature nor mentioned in the CDC diagnosis algorithm (13). Although the mechanism of this coagulopathy remains unclear, we hypothesize these findings are due to the hyperinflammatory status observed in EVALI (14-15).