This is a rare condition in which a young child develops a neuropsychiatric disorder (usually obsessive-compulsive disorder (OCD) or tics) following a Group A beta-haemolytic streptococcal infection (GABHS). Although the acronym PANDAS was first cited in 1998,¹ the neurological sequelae of streptococcal infection have been well recognised (e.g. Sydenham's chorea described by William Osler in 1894).²

Epidemiology

There is still dispute as to whether this syndrome exists as a separate entity from Sydenham's chorea and rheumatic fever. It is likely to have a similar autoimmune aetiology. Onset is between age 3 and puberty (typically aged 6 or 7).³

Presentation

This is usually dramatic, with the sudden development of psychiatric/behavioural problems such as emotional lability, anxiety, night-time fears, hyperactivity and oppositional behaviour with some cognitive deficits. There may be dyskinesias, e.g. mild facial or vocal tics.

The condition follows a relapsing and remitting course. For the diagnosis to be made there should be a temporal relationship between onset/exacerbation (worsening of tics or choreiform movements) and GABHS infection (throat culture or elevated anti-GABHS antibody titres).

If overtly choreiform movements develop, the child should be considered to have developed Sydenham's chorea and these children require antibiotic prophylaxis against subsequent GABHS infection.¹

Management

This is mainly supportive. The case has been made for looking for active streptococcal infection (i.e. take throat swabs if children develop sore throat with pyrexia),¹ and subsequent treatment with antibiotics. Some have even recommended immunomodulatory therapy;^4,5 however, results have been variable.³ Some advocate tonsillectomy.⁶

Tics may be treated conventionally (e.g. with neuroleptic agents). OCD is treated in similar ways whatever the cause, e.g. with behavioural therapy or SSRIs.

Document references

1. Swedo SE, Leonard HL, Garvey M, et al; Pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections: clinical description of the first 50 cases. Am J Psychiatry. 1998 Feb;155(2):264-71. [abstract]
2. Osler W, On Chorea and Choreiform Affections. 1894
3. Gabbay V, Coffey BJ, Babb JS, et al; Pediatric autoimmune neuropsychiatric disorders associated with streptococcus: Pediatrics. 2008 Aug;122(2):273-8. [abstract]
4. Singer HS; PANDAS and immunomodulatory therapy. Lancet. 1999 Oct 2;354(9185):1137-8.
5. Perlmutter SJ, Leitman SF, Garvey MA, et al; Therapeutic plasma exchange and intravenous immunoglobulin for Lancet. 1999 Oct 2;354(9185):1153-8. [abstract]
6. Lynch NE, Deiratany S, Webb DW, et al; PANDAS (Paediatric Autoimmune Neuropsychiatric Disorder Associated with Streptococcal Infection). Ir Med J. 2006 May;99(5):155. [abstract]

Acknowledgements