Abstract
Sensorineural hearing loss (SNHL) is a known complication of cryptococcal meningitis; however, it is unusual for a patient to present with isolated otologic symptoms. We review the case of a patient who is not immunocompromised and who presented with progressive gait instability and sudden onset of left-sided SNHL followed by progression to bilateral SNHL within a 3-week period. Cryptococcal meningitis was confirmed by lumbar puncture with positive cryptococcus antigen in the cerebrospinal fluid. The patient was treated with systemic antifungals, and the hearing loss persisted. The presented report outlines this patient’s unusual presentation and his treatment course and reviews the literature on the otologic manifestations of cryptococcal meningitis.
1
Introduction
Cryptococcal meningitis is an opportunistic fungal infection of the cerebral meninges caused by the pathogen Cryptococcus neoformans , generally seen in patients with human immunodeficiency virus (HIV) or another form of immune suppression. Cryptococcal infection is much more common in patients with acquired immunodeficiency syndrome (AIDS) than in the general population . Cryptococcus infects humans after environmental exposure to soil or pigeon droppings, primarily via inhalation, producing either an acute disease state or latent infection . The central nervous system and respiratory tract are the most commonly affected organ systems.
Central nervous system involvement by the fungus can cause a life-threatening meningoencephalitis, and patients may present with acute, subacute, or chronic infection. Clinical signs and symptoms may be present for several weeks and include fever, headache, cranial neuropathies, altered level of consciousness, memory loss, signs of meningeal irritation, or coma . Patients who are infected but not immunosuppressed are more likely to present with chronic headache or altered mental status, and these nonspecific and vague symptoms may delay diagnosis and treatment considerably.
Of interest to the otolaryngologist are the otologic manifestations of cryptococcal meningitis. Among all patients with cryptococcal meningitis, the incidence of SNHL has been reported to be 27% to 30.8% . Frequently, the change in hearing remains unnoticed as the severity of hearing loss is mild or overshadowed by more obvious neurologic symptoms. Most previous reports of SNHL from cryptococcal meningitis have described the hearing loss as bilateral, sudden in onset, and slowly progressive . Otologic impairment has not previously been reported as an isolated finding in a patient who is not immunosuppressed and with cryptococcal meningitis. We report a case involving a patient with no immunosuppression and isolated otologic findings who was ultimately found to have cryptococcal meningitis.
2
Case
A 62-year-old white man with a several-year history of bilateral presbycusis presented to the otolaryngology clinic for the sudden onset of left-sided hearing loss, tinnitus, and aural fullness 5 days earlier. The patient reported an increase in overall weakness and gait instability for the previous month and was using a cane. An electronystagmogram had been ordered by an outside neurologist and showed a left-beating nystagmus after head shake as well as mild left-beating nystagmus on both left and right Dix-Hallpike maneuvers. Caloric testing showed 39% weakness in the left ear.
Physical examination revealed a normal neurologic examination other than loss of hearing and moderate instability on standing. The patient could not maintain balance without assistance during Romberg testing. Audiogram showed a left-sided profound SNHL at all frequencies and a right moderate high-frequency SNHL (consistent with the patient’s history of presbycusis) ( Fig. 1 ). Magnetic resonance imaging (MRI) of the brain and internal auditory canals (IACs) revealed nodular enhancement in the left IAC, bilateral enhancing facial nerves, and small vessel ischemic disease ( Fig. 2 ). The patient was encouraged to take a course of high-dose steroid tapered for the next several weeks; however, he was reluctant to take systemic steroids and agreed to a low-dose 6-day taper of oral methylprednisolone as well as oral valacyclovir for 10 days as an outpatient.
The patient was seen 2 weeks later with no significant change in hearing or symptoms. Three weeks after initial presentation, the patient developed sudden right-sided hearing loss, which resolved overnight but recurred the following day. In addition, the patient noted new-onset right ear pressure, roaring tinnitus, and a mild spinning sensation leading to occasional falls. The patient’s left-sided hearing loss was unchanged. Physical examination at this time showed a normal otologic and neurologic examination other than loss of hearing bilaterally and moderate instability on standing. A repeat audiogram was obtained and showed a continued profound left-sided SNHL along with a new flat moderate-to-severe right-sided SNHL with a right-sided speech discrimination score of 72% (left side could not be tested) ( Fig. 3 ). A repeat MRI of the brain and IACs showed minimal right IAC enhancement and mild enhancement of the left IAC, slightly more prominent than the prior study.
The patient was admitted to the hospital for further workup of his sudden and progressive SNHL. A neurologic consultation was obtained. Serum Venereal Disease Research Laboratory, toxoplasma titer, lyme titer, cytomegalovirus titer, C-reactive protein, erythrocyte sedimentation rate, antinuclear antibody, and angiotensin-converting enzyme studies were sent and were normal. The result of the HIV test was negative. Empiric methylprednisolone was injected intratympanically on the patient’s right side on hospital day 2. The result of a repeat video nystagmogram was negative for peripheral vestibulopathy, but abnormal saccades on smooth pursuit were noted. A lumbar puncture was performed and showed the following abnormalities of the cerebrospinal fluid (CSF): elevated white blood cell count with lymphocytic predominance, highly elevated protein level, and decreased glucose. Cryptococcus antigen was found to be present in the CSF on latex agglutination test.
The infectious disease team initiated treatment with intravenous amphotericin B and then switched to liposomal amphotericin B (due to worsening renal function during treatment) along with flucytosine. The patient underwent repeat lumbar puncture at 2-week intervals after initiation of treatment for measurement of CSF cryptococcal antigen level, which was still significantly elevated at 4 weeks after initiation of treatment. Serum measurements of cryptococcal antigen were also followed. The patient underwent a full 6-week course of amphotericin. He was then switched to oral fluconazole to complete a 6-month course. The patient did have an episode of catheter-related bacteremia while on his intravenous antifungal regimen that was successfully treated. Repeat audiogram at 4 months postpresentation showed a stable profound left-sided hearing loss and a slightly improved moderate right-sided hearing loss ( Fig. 4 ). The patient underwent several weeks of vestibular rehabilitation and was given an assistive listening device and later a right-sided hearing aid with which he functioned well.
