Pediatric Acute-onset Neuropsychiatric Syndrome (PANS) and Pediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcal Infections (PANDAS) are complex conditions affecting children, causing a sudden and dramatic onset of neuropsychiatric symptoms. Their unique presentation and proposed underlying immune mechanisms challenge medical understanding.
Understanding PANS and PANDAS
PANS and PANDAS are characterized by the abrupt appearance of neuropsychiatric symptoms in children. These often include obsessive-compulsive disorder (OCD), tics, anxiety, and mood changes.
PANDAS is a specific subtype of PANS, where symptoms are triggered by a Group A Streptococcal (GAS) infection, such as strep throat or scarlet fever. In PANDAS, the immune system mistakenly attacks healthy brain tissue following the infection, leading to inflammation and neurological symptoms.
PANS, a broader classification, can be triggered by various infections or other inflammatory processes, not solely strep. The sudden and severe nature of symptom onset is a hallmark for both conditions, distinguishing them from more gradual presentations. Symptoms can include sudden changes in mood, behavior, motor function, and sensory processing.
Current Estimates of Prevalence
Estimating the exact prevalence of PANS and PANDAS remains a challenge, yet available data provide some insight. PANDAS is considered a rare disorder, with incidence estimated at approximately 1 in 1,000 children per year in some studies, or as low as 1 in 11,765 for children aged 3 to 12 years. Other estimates suggest PANDAS affects around 1 in 200 children in the United States, often from parent and physician networks.
PANS encompasses PANDAS and is also considered rare, with its precise prevalence largely unknown. However, some research suggests that as many as 25% of children diagnosed with OCD might meet the criteria for PANS or PANDAS. The PANDAS Network estimates 1 in 200 children are affected by PANS/PANDAS. These conditions typically manifest between ages 3 and 13, with a peak age of onset between 4 and 9 years. Boys are diagnosed more frequently than girls, particularly before age 8, with a ratio of nearly 5 boys for every 1 girl in that age group.
Challenges in Ascertaining Prevalence
Determining the precise prevalence of PANS and PANDAS is difficult due to several interconnected factors.
One significant challenge stems from the evolving diagnostic criteria for both conditions. The criteria have been refined over time, and a lack of universal agreement on these definitions complicates consistent diagnosis across different clinical settings and research studies. This ongoing refinement means that what qualifies as a case of PANS or PANDAS can vary, affecting reported numbers.
Another barrier is the absence of definitive laboratory biomarkers to confirm a diagnosis. PANS and PANDAS are diagnosed clinically, based on a specific set of symptoms and medical history, rather than a conclusive blood test. This reliance on clinical presentation, coupled with the wide range of symptoms and presentations, makes it challenging to standardize diagnosis and epidemiological tracking.
The symptoms of PANS/PANDAS can overlap with other psychiatric and neurological conditions, leading to potential misdiagnosis or underdiagnosis. Children might be incorrectly diagnosed with conditions like OCD, Tourette’s syndrome, or anxiety disorders without considering the underlying immune-mediated cause.
A lack of awareness among healthcare professionals further contributes to underreporting and delayed diagnosis. Many medical providers may not be familiar with PANS and PANDAS, or they might be skeptical about their existence as distinct conditions, which can lead to symptoms being dismissed or attributed solely to psychiatric causes. This limited recognition means that many children with PANS/PANDAS may not receive the correct diagnosis or appropriate care, thus skewing prevalence data.
Impact of Recognition on Reported Incidence
Increased recognition and understanding of PANS and PANDAS are influencing their reported incidence, rather than necessarily indicating a true increase in how common they are. As awareness grows among healthcare professionals and the public, more cases are being identified and correctly diagnosed. This improved diagnostic vigilance means that conditions previously misdiagnosed or overlooked are now being accurately categorized, contributing to higher reported figures.
Advocacy groups and research initiatives play a significant role in this shift by disseminating information and supporting studies. Organizations like the PANDAS Network and the PANS/PANDAS Physicians Network actively work to educate clinicians and families, leading to better identification of symptoms and appropriate referrals.
The ongoing research also helps refine diagnostic criteria, making it easier for medical professionals to identify affected children, thereby impacting the reported incidence. This enhanced recognition ensures that a greater proportion of children experiencing these conditions receive a diagnosis, moving closer to a more accurate understanding of their true prevalence.