HEADACHES IN CHILDREN : A CLINICAL APPROACH

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1 HEADACHES IN CHILDREN : A CLINICAL APPROACH Chong Shang Chee A physician is commonly faced with a child presenting with headaches. The assessment of a child s headache is challenging, but an accurate assessment is critical, so that a proper diagnosis with appropriate investigations and treatment can be instituted. An approach to paediatric headaches, with an evaluative process, management, and some common diagnostic pitfalls and red-flags, is presented. Contents Overview of the problem Challenges in paediatric headache diagnosis and management Evaluation of a child with headache History Specific clues aiding paediatric migraine diagnosis Physical examinations Investigations Medical and non-medical aspects of headache treatment 1

2 Headaches are common in children, and because of their varied etiologies, they are a diagnostic challenge to the primary physician and paediatrician. Although the underlying cause is benign in majority of children, fear of the organic cause eg. intracranial tumours continues to cause much anxiety and concern to parents. From a practical approach, headaches can be divided into two main categories; primary and secondary headaches. Primary headaches encompass of migrainous and tension headaches, which are most common in children. Secondary headaches include conditions related to intracranial and extracranial infections, intracranial mass lesions, and head and neck trauma. Overview of the problem Worldwide epidemiological studies show that, 70% of school children have headaches at least once a year. Chronic recurrent headaches occur in approximately 40% of children at age seven, increasing to 75% by the age of 15. Prepubertal boys are more affected than girls, but after puberty, headaches are more common in girls. The profile of headache types varies according to different settings. Most neurology and headache centres reveal a high prevalence of migraine cases. Local data also shows that paediatric migraine is the most common primary headache type seen in a tertiary setting. In various studies of paediatric emergency setting, the most frequently identified etiology is viral infections (29-39%), followed by migraine and tension headaches (2-29%), rhinosinusitis (9-16%), meningitis (2-9%), shunt malformation or hydrocephalus (2-11%) and tumour (3-4%). Challenges in paediatric headache diagnosis and management The approach to headaches in children is similar to that in adults, but certain diagnoses are less common, while other headache manifestations are more peculiar to children. Often, the diagnosis and description of pain may be difficult, especially in young children. Inference of pain from a child s behaviour, and a detailed history relating to observed signs and symptoms are often required to aid in the diagnosis. Increasingly, neurologists and paediatricians are also recognising the differences between adult and childhood migraine. Treatment differences also exist between adult and paediatric headaches. Evaluation of a child with headache Evaluation of a child with headache begins with a thorough history and medical examination. Priorities in the clinical examination are to exclude a secondary cause. The clinical course of a child s headache often helps to determine the possible underlying causes. There are generally four major clinical profiles of headaches in 2

3 children (Rothner, 1978) and their temporal patterns will assist the physician to the likely causes (Table 1). Table 1: Headache temporal patterns and etiologies Headache patterns Acute Acute recurrent Chronic, nonprogressive Chronic, progressive Suggested etiologies Localised - Acute URTIs eg. sinusitis, otitis media - Dental causes eg. dental abscess, temporal-mandibular joint dysfunction Genera used - Systemic infection eg. meningitis Central - Acute intracranial haemorrhage Migraine Tension-type headache Psychogenic / psychiatric causes Space occupying lesion Benign intracranial hypertension Further detailed questions in the headache history must include location, duration, severity and intensity of headaches. From various studies, it has been found that headaches of chronic duration of more than six months, in the absence of any associated neurological findings or abnormalities, are unlikely to be secondary to an intracranial pathology. A chronic recurring headache, where each episode is short (less than half hour) with mild intensity, and without any associated neurological abnormalities, is also most likely benign. In terms of location, an occipital location of headaches is less common then frontal or temporal, and though a feature of tension headache, should raise the suspicion of a posterior fossa tumour. It is often useful to adopt a pain-scoring system, in particular a pain-faces scoring method for children to help tell mild from severe headaches, as well as monitor a child s response to medications. Necessity for medication use, assess the severity of pain, and bear in mind medication-overuse and medication withdrawal headaches. One should also assess trigger factors and relief factors for headaches. All matters relating to school, friends, hobbies, eating and sleeping habits, and the child s reaction to stressful situations should be discussed. The table below shows the red-flags in headache history, and should alert the physician to a lower threshold for neuroimaging or further investigations. 3

4 Table 2: Red flags in headache history a) A short history ( First or worst ), or recent recurrent severe headache for few weeks b) Accelerated course, change in character over weeks or days c) Headache suggesting raised intracranial pressure (early morning headache, vomiting in morning, pain disturbing sleep, headache worse with cough or valsalva) d) Associated symptoms of personality changes, weakness, visual disturbances, confusion, focal weakness, seizures or fever e) Underlying history of neurocutaneous syndrome, history of systemic illnesses eg. known malignancy with possible metastases, hypercoagulopathy f) Young age of child (<three years old) In the absence of complaints suggesting an organic cause, the history should be directed at establishing the symptoms of a primary headache disorder. Diagnosis of primary headache disorders rests principally on the criteria set by the International Headache Society (IHS) Criteria (Appendix). Specific clues aiding paediatric migraine diagnosis In recent years, there has been increasing awareness of the peculiarities of paediatric migraine, leading to revisions in the IHS diagnostic criteria. Under the new classification, headaches of bilateral location, and also those of shorter duration (one hour instead of two hours) are currently modified for migraine diagnosis in children. Particular to establishing a migraine diagnosis, it is often useful to elicit a family history (familial aggregation in 65-80% of patients), trigger factors, relief by sleep, and also impairment of the child s social functioning. The presence, if any, of aura symptoms, often helps in diagnosis. Migraine in children is strongly associated with other childhood periodic syndromes eg. cyclical vomiting, abdominal migraine, and benign paroxysmal vertigo. Very often, children with migraine frequently suffer from travel sickness and giddiness. Other strong associations are that of stress, depression and psychiatric comorbidities. Physical examination A careful physical examination cannot be overemphasised. A tentative diagnosis is usually obtained after history, and physical examination further substantiates the clinical impression. The neurological examination has a high sensitivity for intracranial pathology, and a careful neurological examination focusing on mental state, coordination, deep tendon reflexes, sensory, motor, eye movement and fundoscopic examination, can exclude a 4

5 brain tumour in 98% of cases (The Childhood Brain Tumour Consortium, 1991). In evaluating a child with suspected meningitis, a physician should be alerted that it is a common phenomenon, even where meningeal infection is present, that neck stiffness or a positive Kernig s sign would be absent, especially in young children. Even in various adult studies, the sensitivity and diagnostic accuracy of Kernig s sign, Brudzinski s sign and nuchal rigidity have been found to be low. Hence if the suspicions of meningitis in a child are high, the child should be carefully evaluated and observed, with appropriate investigations where necessary. The blood pressure should be measured, because hypertension can be potentially missed as a cause of acute or long-standing headaches. A systemic examination for a neurocutaneous syndrome, and for systemic diseases should be performed. Measurements of the head circumference should be done in a young child, to assess for macrocephaly or hydrocephalus. Palpation of the skull and scalp, should be done to elicit localised areas of trauma or skull defect. Temporo-mandibular joint mobility and tenderness, with dental tenderness, and tympanic membrane opacity and mobility should be assessed. If the history is further suggestive, a quick examination for signs of acute rhinosinusitis (sinus tenderness, purulent nasal discharge) may allow effective treatment and resolution of symptoms. In a child where the headache pattern suggests a frontal location and in the eyes, especially after prolonged visual tasks, referral for careful examination by an ophthalmologist to exclude a miscorrected or uncorrected refractive error may be useful. In a child with primary headaches, the physical examination is invariably normal. In clinical practice, increased pericranial tenderness recorded by simple manual palpation can be the single most significant abnormal finding in tension-type headache, and might be useful in assisting in its diagnosis. Investigations In the setting of a child presenting with an acute headache, with abnormalities in history or examination suggesting intracranial pathology, meningitis / encephalitis, or raised intracranial pressure, neuroimaging studies and CSF examination (with measurement of the opening pressure) may be appropriate. Other routine laboratory investigations, and electroencephalogram (EEC) may be indicated in specific clinical settings. For a child with recurrent headaches with no significant neurological findings on examination, current literature does not support performing routine laboratory studies, lumbar puncture or EEC as part of the diagnostic evaluation. Pooled data from various studies also indicate that the EEC is either normal or demonstrate non-specific abnormalities in most headache patients. Currently, data also does not suggest that there are differences in EEG between children with migraine and non-migraine type headaches which may be diagnostically helpful. 5

6 A neuroimaging study is not indicated on a routine basis in a child with recurrent headaches and a normal neurological examination. Neuroimaging should be considered in cases if the history reveals features as discussed previously (Table 2), or physical examination reveals focal neurological findings, signs of increased intracranial pressure, and significant alteration in consciousness or co-existence of seizures (Evidence from AAN. Practice parameter: Evaluation of children and adolescents with recurrent headaches, 2002). In children with non-migrainous headaches lasting more than six months, with a normal neurological examination, the baseline risk for brain tumour is 0.01%. This baseline risk increases to 0.4% in children with migraine symptoms, but this risk does not translate to routine neuroimaging as a cost-effective strategy in the diagnostic evaluation process. Medical and non-medical aspects of headache treatment Secondary headache treatment involves addressing the underlying cause. The diagnosis of headaches should always be reviewed after such treatment, to ensure resolution of symptoms. Children with a short headache history should always be reviewed early, and should be followed up at least six months, to ensure the benign nature of the symptoms. Most studies on treatment and prophylaxis of primary headaches focus on migraine, and in clinical practice, analgesics have not always been shown to be effective in true tension-headache type patients. However, both headache types do involve common physiological mechanisms involving central pain control mechanisms, so treatment must still be tailored to each individual patient s needs and response. Pharmacological treatment In children aged 4-15 years, paracetamol (acetaminophen) at 15 mg/kg and ibuprofen at 10 mg/kg were effective and well-tolerated in headache and migraine treatment. Though paracetamol was more rapid in onset, ibuprofen was more effective in aborting migraine at two hours. Anti-emetics are frequently used concomitantly in children with significant nausea and vomiting associated with migraine, and these include motilium for the younger children, and metoclopromide and prochlorperazine in older ones. The triptans are specific 5-HT lb/1d agonists, and has been favoured in specific instances in acute abortive treatment of migraine. These can be given as oral tablets, injections, and most recently, nasal sumatriptan has been studied as a favourable alternative route of administration. The use of triptans is however more limited in experience for younger children, and more studies on their adverse effects are needed. Adult studies in prophylactic drugs for migraine are more established, though in children the evidence is less convincing. In a Cochrane review of evidence on the use of various prophylactic medications in children, only trials involving propanolol and flunarizine were found to be conclusive in efficacy, when headache frequency was 6

7 analysed as a primary outcome measure (Cochrane database of systematic reviews, 2003). The use of anti-epileptic medications are awaiting larger trials, and their side effects require much consideration when making treatment decisions. Non-pharmacological treatment Stress, problems at school, difficulties in peer relationships, and conflicts in the family can trigger migraine and tension-type headaches. Commonly in migraine patients, flickering or bright lights, smell, fasting and sleep deprivation may also trigger migraine attacks. Often, the child and parents should be informed of such common triggers, and be asked to maintain a sound rhythm in daily life, which includes regular meals, sufficient rest and sleep, and protection against bright sunlight. Food triggers for migraine are common points of controversy, but temporary elimination of specific foods may be advised after close study of a patient s headache and diet diaries. Biofeedback methods, with relaxation therapy have been proven to be effective in headache management in adults and children. Stress management and cognitive therapy may be important aspects of headache management. The clinical interview should identify children with excessive anxiety, behavioural problems, or those who respond poorly to pharmacological methods, and referral for psychological evaluation and counseling may be appropriate in specific clinical cases. Frequent and chronic headache sufferers can encounter significant disability and disruption to social life and school work. Effective treatment of headaches in children results in improvement in their daily functioning. The physician should help monitor the child s attacks with a headache diary, and should refer the child whose headaches may require specific inputs from a paediatrician or neurologist, early. 7

8 Appendix Most recent IHS diagnostic criteria for paediatric migraine with and without aura. MIGRAINE WITHOUT A URA (IHS 1.1) MIGRAINE WITH AURA (IHS 1.2.1) A. At least five attacks fulfilling At least two attacks fulfilling B B-D Aura consisting of at least one of the B. Headache attacks lasting 1-72 hours in following but no motor weakness: children. 1. Fully reversible visual symptoms - positive eg. flickering lights or - negative eg. loss of vision 2. Fully reversible sensory C. Headache has at least two of the following: 1. Unilateral in older children, bilateral in younger children 2. Pulsating quality 3. Moderate to severe pain intensity 4. Aggravation by routine physical activity D. During the headache, at least one of the following: 1. Nausea and / or vomiting 2. Photophobia and phonophobia (in young children inferred from behaviour) E. Not attributed to another disorder. symptoms - positive eg. pins and needles - negative eg. numbness C. At least two of the following: 1. Homonymous visual symptoms and/or unilateral sensory symptoms 2. At least one aura symptom develops gradually over > five minutes and / or different aura symptoms occur in succession over > five mm, 3. Each symptom lasts > five minutes and <60 minutes. D. Headache fulfilling migraine description begins during the aura or follows aura within 60 minutes. E. Not attributed to another disorder. 8

9 Most recent IHS diagnostic criteria for tension headache Infrequent Episodic Tension Headache (IHS 2.1) A. At least ten episodes occurring on <one day per month on average (<12 days per year) and fulfilling criteria B - D B. Headache lasting from 30 minutes to seven days C. Headache has at least two of the following characteristics: 1. Bilateral location 2. Pressing / tightening (non- pulsating) quality 3. Mild or moderate intensity 4. Not aggravated by routine physical activity eg. walking or climbing stairs D. Both of the following: 1. No nausea or vomiting (anorexia may occur) 2. No more than one of photophobia or phonophobia E. Not attributed to another disorder Frequent Episodic Tension Headache (IHS 2.2) A. At least ten episodes occurring on >one day but < 15 days per month per month for at least three months (>12 and <180 days per year) and fulfilling criteria B - D B. Headache lasting from 30 minutes to seven days C. Headache has at least two of the following characteristics: 1. Bilateral location 2. Pressing / tightening (non- pulsating) quality 3. Mild or moderate intensity 4. Not aggravated by routine physical activity eg. walking or climbing stairs D. Both of the following: 1. No nausea or vomiting (anorexia may occur) 2. No more than one of photophobia or phonophobia E. Not attributed to another disorder From: The International Classification of Headache Disorders, 2nd Edition. Cephalalgia 2004, 24(1):

10 Most recent IHS diagnostic criteria for tension headache Chronic Tension Headache (HIS 2.3) A. Headache occurring on> 15 days per month on average for> three months (>180 days per year) and fulfilling criteria B-D B. Headache lasts hours or may be continuous C. Headache has at least two of the following characteristics: 1. Bilateral location 2. Pressing/ tightening (non- pulsating) quality 3. Mild or moderate intensity 4. Not aggravated by routine physical activity eg. walking or climbing stairs D. Both of the following: 1. No more than one of photophobia, phonophobia or mild nausea 2. Neither moderate or severe nausea or vomiting E. Not attributed to another disorder From: The International Classification of Headache Disorders, 2nd Edition. Cephalalgia 2004, 24(1):