Five-year-old female (DK) was referred for vestibular testing and an audiogram by the pediatric ENT to investigate vestibular neuritis as a cause of dizziness. DK’s mother relayed the history information—she thinks the dizzy episodes were related to vaccinations.
The initial episode happened at two years old, DK was seen by her pediatrician for her wellness check and she received a varicella vaccine. The episode began 11 days after her vaccine, the symptoms lasted five to 40 minutes over a period of seven days. She described the dizziness at the time as “the room is moving.” Her mother also noted that DK was having a difficult time walking. She was taken to the emergency room and diagnosed with ataxia. Blood and urine testing, MRI, and EEG were all negative. After seven days the symptoms resolved. The second episode happened four months later, lasting five days, approximately 30 days after receiving a hepatitis B vaccine. DK’s mother noted that the patient was very tired, and her eyes were moving back and forth. DK was taken to the ER for this episode as well, and all testing was negative. The most recent episode was four months before testing. DK’s mother noted that she had been sick for about a week before the episode.
In addition to the symptoms stated earlier, DK also has an infrequent history of a beeping tone in her ears and fullness, and denied a history of hearing loss and visual impairment. There is a family history of dizziness (paternal grandmother) and migraines (mother and aunt). DK’s mother partly filled out the Dizziness Handicap Inventory-Patient Caregiver (DHI-PC), but she did not want it to be part of the medical report since the symptoms were not consistent. The patient is currently in school and participates in horseback riding, swimming, ice skating, and tennis. When asked, DK’s mother stated that her coaches noted she has good balance. When asked, DK reported that she enjoys school and her activities.
Initial Differential Diagnosis
When we examine the symptoms related to the history we note vertigo, nystagmus, ataxia, and fatigue with the episodes. Other significant history is occasional tinnitus, fullness, family history of migraines, great balance (noted by the mother), intermixed history of vaccinations, and all previous testing was normal.
If we pick a few initial theories, the first would be the ENT thought of vestibular neuritis. The timing for the vaccinations and vertigo attacks vary, so the causal relationship is a little strained. Vestibular neuritis can have several causes, but has been related to viral infections. If vestibular neuritis is the cause of the dizziness, the results will present typically as a unilateral peripheral vestibular pattern. Since vestibular neuritis can attack the superior vestibular nerve, inferior vestibular nerve or both, it is important to assess both branches when testing. Labyrinthitis is another vestibular pathology related to viral infections, but labyrinthitis has a sudden unilateral onset of sensorineural hearing loss with the dizziness. There were no complaints of sudden onset of hearing loss.
Migraine would be another suspected pathology in this case given a strong family history of migraine. When queried further, DK’s mother reports that her sister (DK’s aunt) has very bad migraines. She also noted that two other physicians also suggested migraine as the culprit for DK’s vertigo episodes.
Looking at all other potential pathologies, there are reasons to rule most of them out. For example, large vestibular aqueduct syndrome (LVAS) is right for the age, but no significant changes in hearing was noticed, and she seems to be a child with good balance, where many LVAS children tend to be clumsy. If it were LVAS we would see unilateral or bilateral vestibular and hearing loss on testing. Because of her age other pathologies like Meniere’s can be put further down the list because it is very rare in childhood.
Otoscopy was normal bilaterally. Postural screening showed normal postural with Romberg with eyes open and closed on a firm surface, and Romberg eyes open on foam. DK had sway and fall on Romberg eyes closed on foam. Saccades, pursuit, optokinetics, headshake, vertebral artery screening, Hallpike and positionals were all normal.
For calorics, our clinical protocol is warm monothermal water unless abnormal then add cool. We started with right warm, which yielded a great response, but made her cry because she felt it was too hot. (This was a lesson for myself and my AuD students, although I’ve had children tested with warm before and tolerate it, maybe starting with cool would be better). After she was calm, she was brave enough to try again on the other ear with cooler water. This clearly is not the ideal, as it is best to compare the same temperature for each ear, but like testing children in a booth: try to get whatever you can.
For right warm we obtained 29 deg/sec and left cool 27 deg/sec, we cannot calculate a true unilateral weakness, but we can say that each ear on its own is working normally (see FIGURE 1). To correlate these results, we did sinusoidal harmonic acceleration (SHA) testing on rotary chair at 0.04Hz, which was normal (see FIGURE 2).
Cervical vestibular-evoked myogenic potentials (cVEMP) were completed, which showed normal latencies and amplitudes, and an amplitude asymmetry ratio of 4 percent left ear larger, which falls within the normal limits (see FIGURE 3).
Pure-tone testing revealed an essentially mild flat/cookie bite sensorineural hearing loss (see FIGURE 4). Tympanometry and acoustic reflexes were normal. Otoacoustic emission (OAE) screening was completed, which showed robust emissions in the higher frequencies (3-6kHz) (see FIGURE 5).
Going back to our initial list of diagnoses, it does not appear that neuritis or labyrinthitis is the cause. There is no vestibular loss on either side and although surprisingly there was hearing loss, it is not unilateral. Given the completely normal vestibular testing in combination with the history, it appears that migraine is our most likely diagnosis.
The hearing loss was a complete surprise given no history of hearing complaints. Her speech and language are completely appropriate if not advanced for her age. When DK’s mother was questioned further about the hearing loss, she reported that DK failed newborn OAE hearing screening in the hospital and was retested again the following day and failed; this was attributed to DK being born by cesarean section.
DK had a follow-up auditory brain stem response (ABR) testing with normal results at the local children’s hospital, passed OAE, passed school language tests, and failed the hearing screening at school. OAEs performed by a pediatrician in an office setting were normal. DK’s mother was told that since OAEs were normal in the office that it was a more reliable test than the school screening since OAEs are an objective test. Therefore, DK’s mother believed her daughter’s hearing was normal.
Regarding the vestibular complaints, counseling focused around migraine including an official diagnosis by a neurologist, symptoms, and potential progression. According to the International Headache Society’s The International Classification of Headache Disorders, 3rd edition (ICHD-III) classification (2018), benign paroxysmal vertigo (BPV-C) is a migraine variant that affects children, which must meet these diagnostic criteria of five episodes of vertigo plus at least one of the following: nystagmus, ataxia, vomiting, pallor, or fearfulness with normal neurological, audiological and vestibular results between episodes.
As of now, it appears she has three significant episodes that meet these criteria, and there may have been others that did not rise to the same level of concern as the three major episodes. Also, the symptoms appear to have started in a typical age range for BPV-C (Spiri et al, 2014). Long term, it is possible that she will be an adult migraineur (Krams et al, 2010). It was recommended that she follow up with a neurologist to pursue diagnosis and treatment.
Counseling on the hearing loss was more in depth as this was a more unexpected finding with a confusing history. The fact that there were contradictory findings in the mother’s eyes made things more difficult. In this case, the hearing loss is most likely congenital given the configuration and not related to the dizziness. We explained why the OAEs would pass with a mild hearing loss; although the pediatrician was correct about present OAEs and it being an objective test, OAEs are not perfect and there is a range that OAEs can miss a mild hearing loss. We discussed the mild hearing loss in relation to academic success and talked to DK’s mother about amplification options for school.
Since I’m not a “pediatric” audiologist, we had DK’s mother and father return for more counseling, particularly focusing on the hearing loss with our resident pediatric expert. Although amplification was recommended with medical clearance by ENT, DK and family have not returned yet to pursue amplification. Also, DK’s mother also had her hearing tested to see if she had the same hearing loss, her hearing was normal. Finally, they were going to make an appointment with a neurologist to evaluate DK for migraines.
Pediatric vestibular testing is becoming more prevalent and requires modifications to test this population compared to normal adults. This can be a challenge because attention spans are shorter, tracings can be messier, and normative data is not as prevalent as adult data (although it is growing).
Being a vestibular audiologist, the vestibular diagnosis and recommendations comes easier. But diagnosing a child with hearing loss is not as common for me, and I had to draw on information that I do not use regularly. For me, it was a reminder that although I’m a vestibular audiologist who sees pediatric dizziness on occasion, I need to remember that with pediatrics to expect the unexpected.