Varicella-Zoster Virus Infection and Nummular Headache: a Possible Association with Epicranial Neuralgia

□ CASE REPORT □

Varicella-zoster Virus Infection and Nummular Headache: A Possible Association with Epicranial Neuralgia

Wei-Hsi Chen, Tzu-Hui Li, Lian-Hui Lee and Chih-Cheng Huang

Abstract

A nummular headache (NH) is a type of primary headache that results from cranial neuralgia without a known cause. We herein report the case of a woman who suffered two episodes of focal headache in the left parietal area with identical characteristics that were compatible with NH. During the recovery phase of the second NH episode, the pain resurged with shingles coinciding with the painful area. The patient’s NH subsided in parallel with resolution of the shingles. These findings support a diagnosis of peripheral neuralgia with NH. Latent virus infections, such as Varicella-zoster virus, that frequently cause distal nerve damage in patients with zoster sine herpete may be associated with epicranial neuralgia and NH.

Key words: nummular headache, varicella-zoster virus, shingle, zoster sine herpete, neuralgia, neuropathy

(Intern Med 51: 2439-2441, 2012) (DOI: 10.2169/internalmedicine.51.7998)

area measured approximately 4.0×3.0 cm. The pain was Introduction sharp and electric in nature and was described as being lo- cated just beneath the surface of the skin. It occurred spon- The phenomenon of nummular headache (NH), or coin- taneously, reached its maximum point within 10 minutes, shaped cephalgia, was first reported in 2002 (1). The inci- persisted for hours and then later subsided. The headache dence of NH is estimated to be 6.4/100,000/year (2). NH was continuous with episodic exacerbation. Neither aura nor differs from other headache syndromes in its characteristics any associated features were reported. The intensity of the of consistent location, size and shape of the affected area pain was mild to moderate. Triggering, aggravating or re- during each attack (3). In the appendix of the second edition lieving factors were denied; however, the pain was reported of the International Classification of Headache Disorders to significantly worsen when brushing her hair or pressing (ICHD-II), NH was categorized as a component of “cranial the scalp in the painful area (static and dynamic allodynia) neuralgia and central causes of pain” (3). Despite reports of during an attack of pain. The patient denied any antecedent a few cases of intracranial secondaries (4-6), the etiopatho- cutaneous vesicle formation, craniofacial trauma, recent in- genesis of NH is factually unknown at present. We herein fection, chemical exposure or previous history of migraine, report the case of a woman who subsequently developed stroke, herpetic labialis or shingles. She had been diagnosed shingles in an area affected by NH. A seropositivity of IgM with chronic inflammatory demyelinating polyneuropathy and IgG to Varicella-zoster virus (VZV) was identified. The three years prior to the attack. Diagnoses of lymphoma and relationship between viral neuralgia of latent viruses and IgM macroglobulinemia were later confirmed, and both re- NH is discussed. mitted after the patient received appropriate treatment. The patient’s first visit occurred two days after headache Case Report onset. No papilloedema was observed in the fundus. A neurological examination showed no consistent abnormal find- A 62-year-old woman suffered an acute onset of first ings of higher cortical function, cranial nerves, motor func- headache 18 months ago. Her pain was confined to the left tion, sensory system, equilibrium or co-ordination. No per- high parietal area in an oval shape with a clear margin. The cussion pain at the sinus or spine or nodulation or tender-

Department of Neurology, Kaohsiung Chang Gung Memorial Hospital, and College of Medicine, Chang Gung University, Taiwan Received for publication April 19, 2012; Accepted for publication June 7, 2012 Correspondence to Dr. Wei-Hsi Chen, [email protected]

2439 Intern Med 51: 2439-2441, 2012 DOI: 10.2169/internalmedicine.51.7998

acteristics, size or shape of the affected parietal area. In ad- dition, she also felt the same sharp and electric pain in her head at the left ear. At that time, she accidentally found clusters of vesicles within the affected area and in the left ear. On presentation, clusters of vesicles with erythematous bases were seen in the affected area and in the left ear (Fig- ure). A dermatologist confirmed a diagnosis of shingles based on the cutaneous findings and a seropositivity of IgM- VZV and IgG-VZV. Famciclovir was administrated. Head magnetic resonance imaging and autoimmune indices did not disclose any consistent abnormalities. The dose of gabapentin was then increased to 300 mg/day. The patient’s pain completely subsided within six weeks, and a seronega- tivity of IgM-VZV and scarring of the scalp were noted at that time (Figure). Gabapentin was then discontinued. The patient’s lymphoma and macroglobulinemia did not recur during the course of treatment.

Discussion

For our patient, the occurrence of shingles in an area af- Figure. Shingles occurred 14 days after the recurrence of fected by recurrent headaches may be argued to be an acci- nummular headache. The extent of the shingles coincided ex- dental coincidence. However, the congruity of coverage, the actly with the area affected by recurrent nummular head- characteristics of pain and the simultaneous recovery be- aches. The patient placed herbs over her shingles so that they tween the shingles and NH reasonably support the presence looked like discrete black spots (arrows) (A). Shingles were of an association between shingles and NH. Therefore, the also seen on the left ear (arrow) (B). Two months later, the pa- findings of our single patient clearly provide two rational tient had recovered from shingles with some scarring noted pieces of evidence regarding NH: a peripheral origin of pain (arrows) (C). and a probable infection with a latent virus responsible for neuralgia. Until now, there have been two theories postulated regard- ness at the temporal artery were reported. Except for allo- ing NH. The central theory proposes a central sensitization dynia and hypesthesia to pinprick pain and cotton fine of a pain pathway in NH. This theory is supported by a few touch, no changes regarding skin, hair or focal atrophy at cases of intracranial secondaries associated with NH (4-6), the affected area were observed. The results of skull radiog- the complete recovery of pain in a patient after the removal raphy, biochemistry and hemogram were normal. After dis- of a meningioma (6) and the failure of pain control in nerve cussion, gabapentin 100-200 mg/day was prescribed. The block. On the other hand, the peripheral theory proposes the patient’s spontaneous pain and stimulus-evoked allodynia involvement of nociceptive receptors or terminal endings in progressively subsided within one week. Gabapentin was local epicranial tissue. This theory is broadly encouraged by discontinued soon afterwards. the consistent characteristics of pain at the affected area dur- The patient remained well until 18 months later when her ing each pain attack, as well as the alteration of focal sen- headache recurred with characteristics identical to the previ- sory algometry (7) or trophic changes (8) confined to the af- ous headache. As the pain persisted, she consulted the out- fected area in some NH patients. The superficial location of patient service 10 days after recurrence. Upon presentation, pain and stimulus-evoked (static and dynamic mechanical the patient’s vital signs were stable. No fever was noted. A stimulus) allodynia provide additional evidence for a periph- neurological examination did not reveal any remarkable ab- eral origin of pain in NH. Accordingly, the clinical findings normalities. No focal changes related to the scalp, skin or in our patient clearly support a peripheral origin of NH hair at the affected area were observed, except for allodynia. pain. No pain was provoked by percussion at the sinus, spine or Besides the mention of antecedent head injury in a few temporomandibular joint. The ear canals were free of ves- reports of NH (1), the cause of neuropathic change in NH icles. The patient denied any preceding infections. Clini- has not been identified; however, epicranial neuralgia is con- cally, a recurrence of NH was interpreted. Treatment with sidered to be responsible for NH. In our patient, two epi- 200 mg/day of gabapentin was initiated. sodes of painful attack and shingles occurred during the sec- The patient’s pain progressively faded within the initial ond episode of headache. Since the extent and characteris- three days. On the morning of the fourth day, she felt an ex- tics of the pain did not change when the shingles occurred, acerbation of pain intensity without any changes in the char- we believe that the second episode of NH was compatible

2440 Intern Med 51: 2439-2441, 2012 DOI: 10.2169/internalmedicine.51.7998 with VZV-related neuralgia. In fact, VZV can cause neuro- to uncover any latent or subclinical disorders. pathic pain with cutaneous vesicle formation (shingles) or without skin rash (zoster sine herpete) in both the preher- The authors state that they havenoConflictofInterest(COI). petic, acute and postherpetic stages (9, 10). Importantly, post-herpetic neuralgia also occurs with a consistent loca- References tion, shape and size (11), similar to that observed in our patient. Therefore, epicranial neuralgia in NH may be a form 1. Pareja JA, Caminero AB, Serra J, et al. Nummular headache: a of zoster sine herpete. coin-shaped cephalgia. Neurology 58: 1678-1679, 2002. The limitation to our findings is that NH patients are ex- 2. Pareja JA, Pareja J, Barriga FJ, et al. Nummular headache: a pro- spective series of 14 new cases. Headache 44: 611-614, 2004. pected to present with other medical disorders if VZV or 3. Headache Classification Subcommittee of the International Head- other latent viruses are responsible for the neuralgic pain. ache Society. The International Classification of Headache Disor- However, no such studies have been conducted in NH pa- ders, 2nd edition. Cephalalgia 24 (Suppl 1): 1-149, 2004. tients to date. Nevertheless, the simultaneous occurrence of 4. Guillem A, Barriga FJ, Giménez-Roldán S. Nummular headache VZV and NH in our patient establishes a viral model of associated to arachnoid cysts. J Headache Pain 10: 215-217, 2009. 5. Alvaro LC, García JM, Areitio E. Nummular headache: a series epicranial neuralgia for NH. Therefore, NH may not be a with symptomatic and primary cases. Cephalalgia 29: 379-383, primary headache or a headache with a central cause. A de- 2009. tailed investigation between latent viral neuralgia and NH is 6. Guillem A, Barriga FJ, Giménez-Roldán S. Nummular headache warranted. secondary to an intracranial mass lesion. Cephalalgia 27: 943-944, Clinically, NH exhibits a shorter duration of pain than 2007. 7. Cuadrado ML, Valle B, Fernández-de-las-Peñas C, et al. Pressure that observed in zoster-related pain. Regarding trigeminal pain sensitivity of the scalp in patients with nummular headache: neuralgia, the pain in both NH and trigeminal neuralgia lo- a cartographic study. Cephalalgia 30: 200-206, 2010. cates superficially and exhibits consistent characteristics. 8. Pareja JA, Cuadrado ML, Fernández-de-las Peñas C, Nieto C, Sols However, the pain in NH persists for hours and does not M, Pinedo F. Nummular headache with trophic changes inside the have a specific triggering factor as in trigeminal neuralgia. painful area. Cephalalgia 28: 186-190, 2008. Accordingly, NH, zoster-related pain and trigeminal neural- 9. Gilden D, Cohrs RJ, Mahalingam R, Nagel MA. Neurological disease produced by varicella zoster virus reactivation without rash. gia may belong to separate, specific forms of trigeminal Curr Top Microbiol Immunol 342: 243-253, 2010. pain. 10. Mueller NH, Gilden DH, Cohrs RJ, Mahalingam R, Nagel MA. In conclusion, we herein report the case of a woman who Varicella zoster virus infection: clinical features, molecular patho- developed shingles in an area affected by NH two weeks af- genesis of disease, and latency. Neurol Clin 26: 675-697, 2008. ter the onset of the second episode of NH. This association 11. Yawn BP, Wollan PC, Kurland MJ, St Sauver JL, Saddier P. Her- pes zoster recurrences more frequent than previously reported. raises the notion of a potential relationship between latent Mayo Clin Proc 86: 88-93, 2011. virus infection and neuralgic pain in NH patients. Therefore, we suggest the need to establish an appropriate test for NH

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