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short - lasting unilateral neuralgiform headache attacks with conjunctival injection and tearing , ( sunct 3.3 ) is a rare idiopathic headache syndrome characterized by a strictly unilateral headache with prominent autonomic symptoms . in the sunct
the pain is abrupt in onset , of short duration , stabbing or burning in quality , and accompanied by prominent ipsilateral cranial autonomic features , particularly lacrimation and conjunctival injection .
diagnostic criteria are now established which require at least 20 attacks of unilateral , moderately severe , orbital or temporal , stabbing or throbbing pain , lasting for 5240  s and associated with ipsilateral conjunctival injection and lacrimation .
generally , a clustering pattern is reported , with active phases erratically alternating with remissions . during symptomatic periods ,
although the international diagnostic criteria does not refer to symptomatic sunct , more frequently , in previous studies sunct - like syndrome secondary to posterior fossa abnormalities ( arteriovenous malformations , brainstem lesions , skull malformation ) [ 49 ] or associated with neoplastic lesions within the cavernous sinus and pituitary adenomas are reported [ 10 , 11 ] .
many of the basic features of sunct , such as periodicity , autonomic symptoms and unilaterality , are shared with other syndromes , such as trigeminal autonomic cephalalgias ( tacs)i.e . , cluster headache ( ch , 3.1 ) and paroxysmal hemicrania ( ph , 3.2)and trigeminal neuralgia ( tn , 13.1 ) .
though similar pathophysiological basis would subtend these syndromes , the differential diagnosis is a challenge in clinical practice , in order to optimize the therapeutic approach .
in addition , the very early age is a misleading factor for a correct diagnosis .
while a different clinical expression of primary headaches between adult and childhood age is generally recognized , the features of tacs in children are less defined .
the age of onset of sunct is reported from 23 to 77  years with a mean age of around 50 , though sunct - like symptoms were described in single 5- to 10-year - old cases ( table  1).table  1clinical features of pediatric sunctdandrea et al .
skhara et al unalp sexfemalemalemaleage of onset ( years)1056quality of painstabbingburning , stabbingshottingseverity of painvery severevery severevery severesite of maximal painforeheadforehead , orbitorbitattacks per day10180/h46/h every 23  days34/days for 15  daystotal durationmonths with partial remission5  months4  years , regressed after lmt clinical features of pediatric sunct we describe a case of a 2-year - old child presenting symptoms compatible with sunct syndrome , aiming to add further knowledge to tacs features in childhood .
a 2-year - old female came to the neurological emergency room of  giovanni xxiii  hospital in bari , 6  h after the onset of severe facial pain , which occurred soon after awakening . during the first neurological examination ,
the child had a typical pain attack , consisting of an incomplete ptosis of the right eye , with impressive ipsilateral conjunctival injection and tearing .
the location and intensity of pain were deduced by the fact that the child repeatedly beat her right frontal and periorbital regions , showing great suffering and crying to her mother .
the attack lasted 25  s , after which she was pale and very tired .
we thus decided to admit the little patient to our neurological division . on the same day
, the attacks were stereotyped for the occurrence and features of autonomic signs and suffering , with duration , varying from 5 to 30  s. the child presented 40 further attacks during the afternoon , being particularly frequent after the nap and disappearing during night sleep . the next morning
the attacks recurred in a single stab ( from 1 to 6 stabs / h ) , for a total of more than of 40 attacks .
there had been no apparent complications during her mother s pregnancy and subsequent delivery and there was no first degree inheritance for primary headaches or tacs .
cranium magnetic resonance imaging ( mri ) and angiography mri were completely normal without evidence of intracranial or orbital abnormalities .
based on the typical clinical findings and the normal mri , we excluded a secondary trigeminal autonomic syndrome , and supposed a primary sunct .
the spontaneous remission within a few hours made prophylactic therapy unnecessary . at follow - up , after 3  months , the patient was still symptom free .
this is the first case of sunct syndrome occurring in the pre - school - aged child .
the repetitive paroxysmal unilateral pain attacks , associated with ipsilateral conjunctival injection , swelling of the eyelids and tearing , could satisfy the ichd - ii criteria for sunct .
the clinical features of this rare headache resemble other exceptionally rare headaches at this age , but have the following salient differences .
the prominence of autonomic signs , may contribute to exclude trigeminal neuralgia ( 13.1 ) and paroxysmal hemicrania ( 3.2 ) , very rare syndromes in children .
in addition , pain in sunct is maximal in the ophthalmic division , whereas trigeminal neuralgia most commonly affects the maxillary and/or mandibular divisions of the trigeminal nerve .
the short duration of single attacks , could further exclude cluster headache ( 3.1 ) .
sunct syndrome has been reported only in four children aged from 5 to 11 [ 1215 ] .
it was reported as idiopathic in three cases and symptomatic in one case , where an astrocytoma in the ipsilateral pontocerebellar angle was described . in our case , after an active period lasting 2  days , the disease completely disappeared . despite the variability of primary headaches
features in children , the presence of unilateral high - frequency attacks of intense and short - lasting pain , with prominent ipsilateral autonomic signs , number of attacks , seemed to completely satisfy the criteria for sunct diagnosis .
the short duration of the syndrome occurrence , did not exclude sunct in our child and could be the expression of the clinical variability of this disease whose natural history is poorly understood above all in childhood .
a prolonged follow - up will clarify its outcome in our young patient , contributing to add further knowledge to the natural history of this very rare disease .
a 2-year - old female came to the neurological emergency room of  giovanni xxiii  hospital in bari , 6  h after the onset of severe facial pain , which occurred soon after awakening . stabbing 
 pain affected the right frontal and periorbital area , with ipsilateral conjunctival injection , swelling of the eyelids and tearing . except the duration , from 5 to 30  s. 
 , the attacks were stereotyped including the occurrence and features of autonomic signs . 
 based on the typical clinical findings and the normal magnetic resonance imaging ( mri ) , we diagnosed short - lasting unilateral neuralgiform headache attacks with conjunctival injection and tearing syndrome ( sunct ) . the spontaneous remission within a few hours made prophylactic therapy unnecessary . at the last follow - up , after 3  months , the patient was still symptom free . in our case , 
 after an active period lasting 2  days the disease disappeared completely . 
 however the typical features of the disease ( unilateral pain , short duration and high frequency of the attacks , autonomic signs ipsilateral to pain , numbers of attacks ) were all present . while the diagnostic criteria of the international headache society classification for sunct did not include the duration of disease , it is likely that the active period lasting 2  days could be an expression of the clinical variability of the disease .