PANDAS and anorexia nervosa--a spotters' guide: suggestions for medical assessment

Pediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcal infection (PANDAS) should be considered in sudden onset, prepubertal Anorexia Nervosa (AN), arising shortly after an apparent streptococcal infection. However, the absence of a specific biological marker of PANDAS renders the diagnosis difficult. This paper critically reviews available tests for PANDAS and recommends a standardized approach to its investigation.

Medline database review between 1990 and 2008.

Existing tests may be categorized as: (i) Non-specific markers of inflammation or immune response (Erythrocyte sedimentation rate, ESR; C-reactive protein, CRP; Neopterin), (ii) specific markers of streptococcal infection (throat swab and anti-streptococcal antibodies, Anti-streptolysin, ASO; Antideoxyribonuclease B, antiDNaseB), (iii) non-specific markers of auto-immune reaction (Antineuronal antibodies, AnAb; D8/17). No one test reliably identifies PANDAS. The lack of specificity and methodological problems may lead to errors of diagnosis.

When PANDAS-Anorexia Nervosa (PANDAS-AN) is suspected clinically we recommend conducting all the above investigations. The more positive results there are the more likely is the diagnosis, but particular weighting should be given to AnAb and D8/17.