From the Guidelines
The recommended laboratory workup for a teenager with new onset psychosis should include a thorough pediatric and neurological evaluation, complete blood cell counts, serum chemistry studies, thyroid function analyses, urinalyses, and toxicology screens. When evaluating a teenager with new onset psychosis, it is essential to consider the possibility of an organic psychosis and rule out other neurological or medical problems 1. The laboratory workup should be justified on the basis of the clinical presentation and significant findings in either the history or physical examination.
Some key considerations in the laboratory workup include:
- Complete blood cell counts to rule out infections or inflammatory conditions
- Serum chemistry studies to evaluate metabolic function and rule out endocrinopathies
- Thyroid function analyses to assess for thyroid disorders
- Urinalyses to evaluate for urinary tract infections or other renal abnormalities
- Toxicology screens to assess for substance use, which is common in adolescents with schizophrenia 1
Additional tests may be indicated based on the clinical presentation, such as:
- Testing for human immunodeficiency virus if risk factors are present
- Chromosomal analysis if there are clinical features suggestive of a developmental syndrome
- Neuroimaging studies, electroencephalogram, and/or a neurology consultation if there is evidence of neurological dysfunction 1
It is crucial to note that early identification of an underlying cause is vital for appropriate management, as treating the primary condition may resolve psychotic symptoms without requiring long-term antipsychotic medication. Even when primary psychiatric disorders are diagnosed, establishing baseline metabolic parameters is important before initiating antipsychotic medications, which can affect metabolic function.
From the Research
Laboratory Workup for New Onset Psychosis in Teenagers
The recommended laboratory workup for a teenager with new onset psychosis is not well-established, but several studies provide guidance on the approach to take.
- A study published in 2022 2 found that extensive medical testing in the acute setting for psychosis had a low yield for identifying medical etiologies of new-onset psychotic symptoms.
- The study suggests that a thorough history, examination, and workup are necessary to evaluate the patient with first episode psychosis (FEP) 3.
- A conceptual review published in 2009 4 proposes a medical work-up for first-episode psychosis that combines broad screening, exclusion of specific diseases informed by treatability and epidemiology, and medical baseline measures.
Components of the Laboratory Workup
The laboratory workup for new onset psychosis in teenagers may include:
- Laboratory tests such as complete blood count, electrolyte panel, liver function tests, and urine drug screen 2, 4
- Encephalographic and imaging studies where appropriate 3
- Psychological testing and rating scales to assess psychotic symptoms and their differential diagnoses 5
- Liver function tests, which are a helpful screening tool to detect hepatic dysfunction 6
Approach to the Laboratory Workup
The approach to the laboratory workup for new onset psychosis in teenagers should be clinically guided, with a thoughtful consideration of the differential diagnoses and a tiered approach to the workup 3.