Clinical characteristics of paediatric Hashimoto's encephalopathy

Hashimoto's encephalopathy, also known as steroid responsive encephalopathy, is associated with thyroid antibodies (SREAT) and is a rare but serious form of encephalopathy. In this paper, we describe the signs, symptoms, outcome, and treatments as noted in the case reports reviewed.

We searched PubMed, Embase, and the Cochrane library for articles in which cases of Hashimoto's encephalopathy were described. The case description had to include the diagnosis, age, sex, presenting symptoms, and diagnostic tests.

We retrieved 360 articles and 65 fulfilled the inclusion criteria. These articles gave reports of 100 cases, with a mean age of 10.9 (range 2.8-19), 78 of whom were female. Epilepsy (79) - including epileptic state [24] - behavioural problems [36], hallucinations [21], headache [21], and decline in school performance [19] were most often reported. Antithyroid peroxidase (aTPO) was reported elevated in all patients. Most children [70] recovered fully, however 16 had late sequelae, mostly epilepsy. Therapies used include steroids, intravenous gammaglobulines, and cytostatics.

Epilepsy, behavioural problems, decline in school performance, and hallucinations are frequent symptoms of Hashimoto's encephalopathy. Steroids are the basis of treatment, although other immunomodulatory drugs seem to be successful. About one in ten children will experience late sequelae. In any child with unexplained neurological, psychiatric, or psychological dysfunction, serum anti-thyroidperoxidase (aTPO) should be determined.