Abstract
The paper by Leone et al. (1) is interesting, as it presents a case of cluster headache sine headache, i.e. cluster headache exclusively with autonomic symptoms. A similar case has recently been described in the literature (2). This patient had originally cluster headache sine headache but developed typical cluster headache 6 years later. The case by Leone et al. (1) had never had headache during the 15 years she had experienced the autonomic cluster headache symptoms. It is highly likely that cluster headache sine headache is cluster headache. Substantial support for this view is that the first case later developed cluster headache, while the second case had a father and a son with cluster headache. The spectrum of cluster headache may be even broader. One of the twins in an identical twin pair had cluster headache, while the other had cluster headache-like symptoms a few times a week of very short duration, and years later developed cluster headache (3). Another patient had cluster headache without autonomic symptoms (4). The latter had an uncle with typical cluster headache.