Bullous pemphigoid and amyotrophic lateral sclerosis: a new clue for understanding the bullous disease?

BACKGROUND Bullous pemphigoid (BP) occurs in many patients with multiple sclerosis. Isolated cases of BP in patients with other neurological disorders further support a pathogenic association between cutaneous and neurological diseases. Any description of BP in patients with amyotrophic lateral sclerosis is lacking. OBSERVATIONS We studied a French population of 168 patients with typical amyotrophic lateral sclerosis. Among these, 3 had clinical and histological features of BP. The mean age of the patients was 54 years. None was known to have autoimmune disorders. Results of immunoblot analysis disclosed both anti-BP antigen 1 and anti-BP antigen 2 antibodies. CONCLUSIONS Bullous pemphigoid seems to be unexpectedly associated with amyotrophic lateral sclerosis. On the basis of the cases presented herein, we discuss the epidemiological significance of the association and the possible interrelation between BP antigen 1 and neurofilaments in the pathogenesis of both disorders.