Preliminary results from our ongoing FEP project seem to be promising. There are certain sample features making our cases unique regardless of their autoimmune status, which is unclear at this stage. Out of 15 recruited patients, seven were under 20 years. Our 3-month criteria for FEP, compared to our earlier samples with six-month criteria (
17-
19), let us recruit a younger population compared to some other studies. This is in concert with recent proposed criteria for autoimmune psychosis as well (
1). Moreover, anti N-Methyl-D-aspartate receptor (anti-NMDAR) encephalitis is more frequent in children and can present with psychosis (
8). As Moreno et al. found, we are hoping that younger age of onset could lead to more cases of identifiable autoimmune psychosis (
20).
Almost all of the patients had prodromal symptoms characterized by either psychiatric or physical symptoms, such as viral or neurological symptoms. This is in line with studies like Dalmau et al. (
21) and Maneta et. al., who described flu-like symptoms among the factors that should prompt consideration of anti-NMDAR encephalitis in FEP (
22).
We enrolled four Afghan cases, which is proportionally higher than expected. This is interesting as there is a growing body of evidence suggesting an increased risk of developing psychosis in migrant groups (
23). Data on ethnic proportionality of autoimmune encephalitis is limited (
24), and findings of our study may shed light on this uncovered area. In general, this group clinically resembled the common population of FEP in their presentations.
The most prevalent type of delusion was persecutory delusion, with reference delusion coming afterward. Our findings were consistent with few existing data on the theme of delusions in FEP reporting paranoid and reference delusion, the two most common delusions (
25,
26). Eleven patients experienced hallucinations. This is in accordance with previous studies reporting the prevalence of hallucination in FEP at about 75% (
26). Similarly, auditory hallucinations was reported to be the most prevalent type of hallucination in FEP followed by visual hallucinations (
26).
However, there are some findings making our sample somewhat distinct. Five patients presented with catatonic symptoms. The prevalence of catatonia is not clear in FEP, but it is estimated to be range from 0.6 to 17% in children and adolescents (
27) and 10 - 25% in mixed inpatient populations of psychiatric institutions (
28,
29). In a recent case series, Averna et al. described four cases of FEP with accompanying symptoms of catatonia (
27). Two of the cases were tested positive for anti-NMDAR antibodies. They were treated with risperidone without any benefits. The authors suggested psychiatrists should be aware of anti-NMDAR encephalitis in patients presenting with psychosis and dyskinesia, seizures, or catatonia to reduce diagnostic and therapeutic time delays.
Nearly half of our patients had formal thought disorders. In their study in 2019, Gibson et al. proposed psychiatric patients with anti-NMDAR encephalitis may suffer from formal thought disorders more than those with the typical presentations of FEP (
30).
The prevalence and criteria for the identification of autoimmune psychosis cases have been the subject of various recent studies (
1,
3). Our ongoing study similarly aims to investigate specific psychiatric profiles of such cases.
5.1. Challenges
This study has been underway in a large nationally known psychiatric hospital (Roozbeh Hospital). Some specialized services for patients with FEP, including medication and patient and family psychoeducation, are well established in this hospital. However, the referral rate has been lower than expected, given the prevalence rate of psychosis. This requires a more active recruitment strategy and education for relevant colleagues.
As a psychiatric hospital, we lack timely access to other medical teams. This, in turn, leads to practical challenges with regard to medical workups. We had to outsource some investigations; for instance, there is no MRI unit in the hospital, and specialized serum and CSF tests are not provided in the hospital laboratory. Also, patients with high fever and loss of consciousness had to be transferred to general hospitals. There are also conceptual barriers working in a psychiatric hospital as some patients and even staff consider psychiatric disorders as non-medical conditions. As such, some patients and families may feel reluctant to undergo lumbar puncture as an invasive intervention.
In this preliminary report, we provided information for the first 115 patients recruited to the study, which is obviously limited and far from our actual sample size; thus, it prevents us to draw any absolute conclusions. The most likely limitation of our study is loss to follow-up, especially in patients who became completely symptom-free after the experience of the initial episode. To address this potential barrier, we will keep our touch and educate the patients and their families. Another potential reason for patients being lost to follow-ups may be financial issues. Therefore, the costs of all diagnostic workups in addition to patient and caregiver transportation is covered by the study.
5.2. Conclusions
Studying FEP with acute onset is of paramount significance to estimate the prevalence and characteristics of autoimmune psychosis cases as a potential curable group of patients. However, there are challenges to achieve this goal, particularly working in a psychiatric hospital. Identifying specific criteria to arrive at the diagnosis of autoimmune psychosis would be a major milestone to achieve in future studies.