- Millions of Covid-19 tests have been performed without incident , but in a rare case, a test led to life-threatening complications
- The US patient's case was documented in a medical journal this month
- Doctors who reported on the case emphasised the need for vigilance when carrying out tests
A 40-year-old US woman who underwent a Covid-19 nasal swab test experienced more than just an uncomfortable itch and tickle; the swab procedure ended up rupturing the lining at the base of her skull, causing cerebrospinal fluid (CSF) to leak from her nose and putting her at risk of brain infection.
The case was reported in the medical journal, JAMA Otolaryngology – Head & Neck Surgery this week.
The doctors wrote that the patient had an rare undiagnosed condition, and that the test she received may have been carried out improperly, causing the rupture. This means that health risks associated with nasal swab tests remain very low.
Oral testing better alternative in some cases
The patient had a compulsory Covid-19 test ahead of an elective hernia surgery.
Shortly afterwards, she started noticing clear fluid coming out of one nostril, and subsequently developed headache, vomiting, neck stiffness, metallic taste and photophobia (aversion to light), the case report reads.
Although her case is a rare event, Jarrett Walsh, senior author of the paper told AFP that her case shows that healthcare professionals should take special care to follow testing protocols closely, and that patients who have undergone extensive sinus or skull base surgery should consider requesting oral testing if available.
"She [the patient] had been swabbed previously for another procedure, same side, no problems at all,” said Walsh, adding: “She feels like maybe the second swab was not using the best technique, and that the entry was a little bit high.”
Patient’s case history played a role
The patient had also been treated years earlier for intracranial hypertension, according to the case report. This means that the pressure of the cerebrospinal fluid that protects and nourishes the brain was too high.
At the time, doctors drained some of the fluid and the condition resolved, but she later developed a defect at the base of her skull, called an encephalocele, which led to the brain's lining protruding into the nose, making it susceptible to rupture.
The encephalocele went unnoticed, but her new doctors picked it up when reviewing her old scans. They then performed surgery to repair the defect in July, and wrote that she had since fully recovered.
According to Walsh, she may have developed the symptoms due to irritation to the lining of the brain.
Had the problem remained untreated, it could have led to a life-threatening brain infection from bacteria travelling up the nose, or air could have entered the skull and put excess pressure on the brain.
Despite such cases being few and far between, Walsh stressed the need for high-quality training, considering that hundreds of millions more Covid-19 tests will be carried out before the pandemic is over.