TORONTO -- Canadian doctors have linked natural, oil-based decongestants to a case of persistent pneumonia in a 30-year-old patient who regularly gargled with flax seed oil and used a sesame oil nasal spray.
According to a case report published in the peer-reviewed on Tuesday, the Polish man, who had been living in Toronto as a student for the majority of the previous two years, visited the emergency department for left-sided chest pain.
The report notes that he had been diagnosed with pneumonia in Poland about two weeks earlier and was treated with a 14-day course of clarithromycin, an antibiotic.
The man was a lifelong non-smoker, rarely drank alcohol and did not use any recreational drugs or electronic cigarettes. According to the report, his medical history included irritable bowel syndrome, recurrent sinusitis and persistent symptoms of dry mouth that started after a tonsillectomy.
Despite multiple courses of antibiotics, doctors said his symptoms of chest pain and shortness of breath recurred repeatedly and the pneumonia failed to resolve.
While multiple CT scans ruled out pulmonary embolism, the report said the scans showed "persistent bilateral consolidations, nodules and ground-glass opacities" in the right middle lobe, right lower lobe and left lower lobe of the lung.
Upon further investigation, the doctors say a biopsy detected a foreign substance surrounded by inflammation in the patient's lung. Another test also showed yellow mucoid secretions arising from the right lung.
According to the case report, the patient's cell samples were normal and culture samples showed no evidence of harmful bacteria, fungi or viruses, including SARS-CoV-2, the virus that causes COVID-19. Abnormal deposits in the lungs were also excluded.
"This prompted us to take a detailed history of environmental exposures to vaping liquids, silica, asbestos, talc and numerous other organic and inorganic materials," the report's authors wrote.
The physicians report that the patient denied these exposures, but had disclosed that he had been "swishing and spitting" flax seed oil for the past 12 years to help with his symptoms of dry mouth. He also said he recently began coughing after this process.
In addition, the patient reported that he had been using a nasal decongestant of natural sesame oil for the past two years to help with his sinusitis.
Doctors report that the use of these products caused the patient to inhale small oil droplets, which led to lung inflammation and pneumonia.
"Given this exposure history and consistency with the pathology results, we diagnosed exogenous lipoid pneumonia and counselled the patient to stop the antibiotics and oil products," the author's wrote.
According to the case report, exogenous lipoid pneumonia is a rare cause of non-resolving pneumonia that may present with a superimposed bacterial infection.
Doctors reassessed the patient three months after he stopped using the flax seed oil and sesame oil nasal spray. The patient reported feeling better and less tired, but still experienced some shortness of breath if he exerted himself. Doctors said pulmonary function tests done at this time also showed improvements in his lung volumes.
The authors note that this case emphasizes the value of taking into account a full patient history in making an accurate diagnosis.
"Our case highlights the importance of taking a detailed history that includes exposure to fatty or oily substances, particularly when inhaled or applied to the nasopharynx or oropharynx, as part of the work-up for non-resolving pneumonia," they wrote.
The authors have reported this adverse event from using the sesame oil nasal spray to the Natural Products Directorate of Health Canada.
