Pediatric neurotology.[FIGURE 1 OMITTED]
A 9 1/2-year-old girl presented with a 2-month history of painful aural fullness bilaterally, rotary vertigo, nausea, and severe headache. She was generally symptom-free when she awoke in the morning, and she experienced only minor symptoms during the day. However, her symptoms typically intensified after dinner and persisted into the evening. The ear pain was followed by 10-minute episodes of vertigo, which were followed in turn by bifrontal headaches that extended down to the maxillary sinuses. The intensity of the dizziness varied, and when it was severe, it would lead to nausea. Neither the ear pain nor the headaches were relieved by ibuprofen, although the dizziness was eased by lying down. The patient also reported some intermittent tinnitus in both ears, but it was not necessarily associated with the dizziness. There was some underlying clogging in the left ear, but no subjective hearing loss. Her family history was positive for dizziness.
On neurotologic evaluation, the sharpened tandem Romberg test was positive with either foot forward. Palpation revealed nuchal spasm bilaterally and tenderness on the left. Recent audiometry had demonstrated a low-frequency, mainly conductive hearing decline in the left ear with normal tympanometry. Videonystagmography detected a transient left-beating nystagmus with the head left. The patient was placed on 1 mg of cyproheptadine three times daily and asked to return 1 month later.
At her next visit, the patient reported that the nausea had disappeared and that the headaches were diminished, but she was experiencing even more ear pain. Electronystagmography found no spontaneous or positional nystagmus. The alternate binaural bithermal caloric test showed a 38% reduced vestibular response right and a directional preponderance of 54% to the right. The simultaneous binaural bithermal test showed a type 1 response with no nystagmus produced. The sinusoidal vertical-axis rotation test showed normal gains, a phase lead at 0.32 Hz, and no abnormal symmetry. Thin-section computed tomography of the temporal bones detected evidence of bilateral otosclerosis-like lesions (spongiotic and sclerotic lesions) and pericochlear lucency. Distortion-product otoacoustic emissions testing showed less of a response on the left (figure 1). The laboratory evaluation revealed a flat glucose tolerance test with hyperinsulinemic levels and elevated age-adjusted levels of total cholesterol (191 mg/dl) and low-density lipoprotein (LDL) cholesterol (124 mg/dl). She was placed on a modified hypoglycemic diet low in fat, and she was prescribed a regimen of sodium monofluorophosphate, calcium, and vitamin D. The cyproheptadine was continued. (For purposes of elucidating the chronology of this case, treatment of the patient's symptoms is considered to have been initiated at this second visit.)
[FIGURE 2 OMITTED]
Three months later, she returned and reported that her headaches had disappeared altogether and that her nausea had not recurred. However, she complained of some bilateral neck to shoulder pain while lying down and associated ear pain. Her dizziness was "not really too bad;' occurring occasionally when she got into and out of bed. She was able to discontinue the cyproheptadine. Tinnitus would occur when she felt dizzy while lying down. She had complied with her diet "more or less" and her total cholesterol and LDL cholesterol levels fell slightly to 184 and 121 mg/dl, respectively. A 2-hour glucose tolerance test again showed flat responses, and her insulin level had decreased. Sinusoidal vertical-axis rotation testing showed normal gains and normal phases; the latter represented an improvement over the previous test, indicating that a shift in peripheral vestibular function had occurred (figure 2). There was abnormal symmetry to the right at 0.01 and 0.04 Hz, which indicated incomplete central vestibular compensation of the improved vestibular function. Otoacoustic emissions testing revealed improved responses in the left ear (figure 3). Her current treatment was continued.
[FIGURE 3 OMITTED]
She returned 10 months into treatment and reported no aural fullness, ear pain, dizziness, nausea, headache, neck ache, or tinnitus. Her elevated serum cholesterol levels remained the same. A follow-up sinusoidal vertical-axis rotation test again revealed normal gains and normal phases, and her previously abnormal symmetry improved into the normal range, but the previous findings at 0.16 and 0.32 Hz had migrated into the abnormal range and to the right. Her regimen of sodium monofluorophosphate, calcium, and vitamin D was continued, and her dietary management was passed on to her pediatrician.
[FIGURE 4 OMITTED]
She returned 18 months into the treatment and remained completely asymptomatic. Her dietary compliance had waned since her previous visit. Sinusoidal vertical-axis rotation testing continued to show normal gains and phases; the previous abnormal symmetry reverted to normal, and the previous finding at 0.01 Hz became abnormal right (figure 4).
This case illustrates several clinical points. First, children may present with neurotologic symptoms caused by early-onset otosclerosis-like lesions of the otic capsule. Symptoms of this nature are unusual in this age group, and otosclerosis as an etiology is rare. In this case, the patient's abnormality was demonstrated by electronystagmography--particularly caloric testing--rather than by rotation testing. This circumstance highlights the importance of performing both tests of vestibular function. The rotation test was delayed compared with electronystagmography in demonstrating a vestibular abnormality, and the rotation test findings remained abnormal even as the patient's symptoms abated.
A second important clinical point is that while this child demonstrated normal hearing to 20 kHz, she showed abnormal otoacoustic emissions before beginning treatment. This abnormality resolved early during treatment.
Third, the search for answers to vestibular problems by looking for metabolic abnormalities led to the discovery of abnormal levels of both blood glucose and lipids. But the patient's good response to the otosclerosis treatment made it seemingly less urgent to comply with recommended diet and lifestyle changes. Finding metabolic abnormalities and getting the cooperation of the parents, pediatricians, and patients in treating them are likely to prevent future health problems. Since full bone growth does not occur until patients reach the age of 18 to 20 years, the use of bisphosphonates in children is contraindicated.
Fourth, the sinusoidal vertical-axis rotation test continued to show abnormal symmetry even when the patient was asymptomatic. This finding suggests that early discontinuation of treatment could have resulted in a recurrence of symptoms.
Finally, a young girl in such a situation may experience a recurrence of symptoms driven by menarche.
Kenneth H. Broolder, MD, MS, FRCSC