A case study details three teenagers with mild or asymptomatic COVID presented with suicidal thoughts, “paranoia-like fears,” delusions and “foggy brain”, which could be explained by anti-neural antibodies – ‘turncoat’ antibodies that may attack brain tissue.
Mounting evidence points to neurological and psychiatric effects of COVID, with a UK study finding a 13% risk of a first-time diagnosis after COVID. The study, published in JAMA Neurology, is the first to look at anti-neural antibodies in paediatric patients previously infected with SARS-CoV-2.
Over five months in 2020, 18 children and teens were hospitalised with confirmed COVID at UCSF Benioff Children’s Hospital San Francisco, three of whom were the patients in the study who underwent neurological evaluations.
The researchers examined the patients’ cerebrospinal fluid (CSF) and found that two of the patients, both of whom had histories of unspecified depression and/or anxiety, had antibodies indicating that SARS-CoV-2 may have invaded the central nervous system. They also had anti-neural antibodies in their CSF, suggesting a rampant immune system accidentally targeting the brain.
The research follows a previous UCSF study that also found a high level of autoantibodies in the cerebrospinal fluid of adult patients with acute COVID, who experienced neurological symptoms, including intractable headaches, seizures and loss of smell.
“It is way too soon to know whether COVID is a common trigger for neuropsychiatric illnesses, but it does seem to be a potent trigger for the development of autoantibodies,” said co-corresponding author Samuel Pleasure, MD, PhD. “It is currently totally unknown whether patients predisposed to neuropsychiatric illnesses are more likely to develop worsened symptoms after COVID, or whether COVID infection can act as an independent trigger.”
Unlike most psychiatric presentations, the three patients in the UCSF study had symptoms with sudden onset and rapid progression, representing a marked change from their baselines, said co-first author Claire Johns, MD. “The patients had significant neuropsychiatric manifestations despite mild respiratory symptoms, suggesting potential short and long-term effects of COVID.”
After hospitalisations lasting weeks and ongoing psychiatric medications, the two UCSF patients, whose cerebrospinal fluid tested positive for SARS-CoV-2 antibodies and anti-neural antibodies, were treated with intravenous immunoglobulin, an immunomodulatory therapy that curbs inflammation in autoimmune disorders. After five days, the first patient had “more organised thoughts, decreased paranoia and improved insight.”
Autoantibodies targeting the protein TCF4 were also found, which has genetic links in some schizophrenia cases. However, “we don’t know that the antibodies are actually interfering with the protein’s function,” said co-corresponding author, Michael R. Wilson, MD, noting that the diagnosis of schizophrenia is based on a constellation of symptoms, not a biomarker.
The second patient partially responded to immunotherapy with improved cognition and working memory, but continued to have “impaired mood and cognitive symptoms” six months later. The third patient, with no psychiatric history and without SARS-CoV-2 antibodies or anti-neural antibodies in their cerebrospinal fluid, recovered with psychiatric medications. Their symptoms were attributed to recreational drug use.
In another case study, a 30-year-old patient with mildly symptomatic COVID who presented at a hospital emergency department with delusions, violent outbursts, hyper-anxiety and paranoia was unresponsive to antipsychotic medication but after being diagnosed with possible “autoimmune-mediated psychosis”, responded to intravenous immunoglobulin.
Nonetheless, the researchers agree it’s unlikely that there were pre-existing autoantibodies, and they point to other disorders with psychiatric symptoms, like anti-NMDAR encephalitis syndrome, that are caused by anti-neural antibodies and respond to treatment directed at these rogue antibodies.
The researchers agree that more study is warranted, although Dr Pleasure noted that the rarity of cerebrospinal fluid samples from paediatric patients is a challenge, as they rarely have severe enough COVID to warrant a lumbar puncture.
