Medical Excellence - Issue 2

Discussion Red ear syndrome is a clinical diagnosis for which there is no specific diagnostic test. One hundred cases have been reported in the literature so far, with an estimated male-to-female ratio of 1:1.25 and a median age at onset of 44 years (with a wide range of ages: 4 to 92 years) [1]. Lance [2] was the first to describe RES in the literature in a 1996 report of 12 patients with recurrent RES. Pain in RES varies from mild to severe [3,4]. Its duration may be seconds [5] or hours [2]. The frequency of episodes may be several times per day, or there may be year-long remission periods [6]. Raieli and colleagues [4] reported that unilateral or bilateral 30- to 60-minute episodes can occur in isolation and be associated with migraine (before, during or after). In 10% of the cases they reported, red ears preceded onset of a painful migraine attack. In their series of 96 children admitted with headache, who ranged from 6 to 18 years of age, 55 (57%) had migraine, and RES was found in 16 migraine cases. RES did not occur in the other headache groups. It was associated with severe pain in 62.5% and neurovegetative symptomatology (nausea, vomiting, phonophobia and/or photophobia) in 50% [4]. Episodes have been reported to occur spontaneously or to be triggered by heat [2]; by entering a hot room [7]; by touch [2,5]; by neck movement [2,5]; by sneezing, coughing, hair- brushing, physical exercise, chewing, and stress [2]; and by expo- sure to cold and lying on the affected side [8]. There are various views regarding the pathophysiology of this condition. Lance [2] suggested that the syndrome is induced in patients with cervical disorders, predominantly C3 root dis- charge causing antidromic release of vasodilator peptides (pe- ripheral mechanism). He proposed that the primary mechanism is activation of the trigeminovascular system. He pointed out, and Hirsch [9] reiterated, that parasympathetic vasodilatation is greater in the nose and cheek than in the ear; therefore, red ears must be mediated primarily by inhibition of sympathetic vasoconstriction or activation of sympathetic vasodilatation. Thus, the presence of RES suggests an underlying dysregula- tion of sympathetic outflow. Purdy [10] noted that, in RES, there is pain in and around the ear associated with autonomic phe- nomena, including erythema of the ear ipsilateral to the pain. He suggested that the condition be labeled auriculo autonomic cephalalgia or be placed in the trigeminal autonomic cephalgia group. Several authors, including Kumar and colleagues [5], have used brainstem trigeminovascular activation to explain RES as- sociated with migraine. Lambru and colleagues suggested that it is possible that trigeminoautonomic parasympathetic activation occurs with sympathetic deficit. The imbalance between para- sympathetic and sympathetic systems thus may facilitate inhibi- tion of sympathetic tone of the ear. Sympathetic dysregulation, not parasympathetic activation as formerly believed, may be the predominant mechanism of RES [1]. Another group [7] has suggested that RES is an auricular form of erythromelalgia with similar burning pain, erythema and increased skin temperature. Erythromelalgia is a condition affecting hands and feet that might be caused by sensory and sympathetic nerve dysfunction. Red ear syndrome has been associated with various condi- tions, including upper cervical pathology (arachnoiditis, facet joint spondylosis and cervical root traction), glossopharyngeal and trigeminal neuralgia, temporomandibular joint (TMJ) dys- function and thalamic syndrome [2]. Associations have been reported with primary headache disorders, including migraine, chronic paroxysmal hemicranias [3], hemicrania continua and the short-lasting unilateral neuralgiform headache with con- junctival injection [11]. Other cases are idiopathic. Donnet and Valade proposed two types of RES: (1) a primary form that occurs in young people and is associated with migraine and (2) a second- ary form that occurs in older adults and is associated with cervical disorder or trigeminal autonomic cephalalgia phenomenon [6]. Various treatments for RES have been used with varying success. Among the 12 patients Lance described, one improved with methysergide therapy. One experienced partial symptomat- ic relief with indometacin, and others with propranolol, applica- tion of a cold pack, amitriptyline, or imipramine [2]. Inconsistent results have been reported following treatment with non-steroidal anti-inflammatory drugs [12], topical anes- thetics, cooling the ear [7], verapamil and gabapentin [8] and greater auricular nerve blockade with a combination of local anesthetics and steroids. Some authors have reported relief over an eight-week period, and others have noted no benefit [2,13]. Bender [14] suggested that in primary or idiopathic cases, treat- ment of the coexisting headache disorder with drugs such as propranolol, amitriptyline, imipramine and flunarizine helps to resolve these cases to varying degrees. Secondary forms may be more resistant to treatment [12]. In one review, secondary cases appeared to have a greater response to treatment than idiopathic cases [15]. In secondary cases, such as those associated with TMJ dysfunction, a dental plate was reported to be useful in reliev- ing symptoms [2,9]. In cases associated with chronic paroxysmal hemicrania, indometacin was found to be effective [3,16]. Transient unilateral sensation of aural fullness with tinnitus was described in one of Lance’s original cases [2] and blockage without tinnitus in 2 further cases of chronic paroxysmal hemi- crania [3]. Aural fullness was present in our case on the first presentation; additional subjective hearing loss in background noise without evidence of hearing loss on audiometry was pos- sibly due to central auditory pathway changes. Issue-2  |  3 MEDICAL EXCELLENCE