Abstract
Reversible sensorineural hearing loss is a recognised complication of cryptococcal meningitis. Cryptococcal meningitis typically presents with usual symptoms of fever, headache and neck stiffness. This case highlights acute, profound, bilateral hearing loss as the initial symptom and presentation of cryptococcal meningitis in a young woman, who was later diagnosed with AIDS.
Keywords: cryptococcus, infectious diseases, HIV / AIDS, meningitis, ear, nose and throat/otolaryngology
Background
Cryptococcal meningitis is caused by Cryptococcus neoformans with infection occurring via inhalation, with subsequent haematogenous spread to the meninges and brain. Cryptococcal infection is more common in patients with AIDS, usually with a CD4 cell count <100 cells/UL. Patients typically present with usual meningitis symptoms including fever, headache, neck stiffness and photophobia. Acute hearing loss can be one of the less common symptom manifestation of cryptococcal meningitis.
Case presentation
A 46-year-old woman with no known comorbidities presented with decreased hearing acuity bilaterally. She exhibited slow mentation, reticent to respond, however, was able to communicate by writing slowly. She endorsed a 5-day history of feeling unwell reporting a constant headache, generalised weakness and decreased hearing acuity. Her history was limited as the patient was poorly alert, lethargic and very slow to respond.
Physical examination revealed a somnolent, cachectic, ill-appearing woman with a fever of 101.8F. The patient had loose skin, suggestive of recent excess weight loss with mild temporal wasting. The patient had profound bilateral hearing impairment requiring written text in order to facilitate history-taking. Otoscopic examination in the emergency department revealed clear auditory canals, however, the patient reacted with painful discomfort on manipulation of her neck during the examination of her ears. Despite her slowed mentation, she grimaced in painful discomfort on passive range of motion, most notably on head flexion. With her waxing and waning mental status, a CT head and urine drug screen was done.
Investigations
CT head revealed no acute pathology and urine drug screen returned negative. As the patient was febrile with neck stiffness and slow mentation, a lumbar puncture was pursued. Bedside funduscopy was not performed as the patient’s CT head revealed no evidence suggestive of increased intracranial pressure. Again, communication was limited by the patient’s new onset hearing loss, that the lumbar puncture procedure had to be described in writing in order for the patient to give consent.
Opening pressure was elevated at 49 cmH2O. Cerebrospinal fluid (CSF) analysis revealed a gram-stain suggestive of yeast with a positive cryptococcal antigen test. The patient was admitted for management of cryptococcal meningitis.
HIV testing returned positive. Blood cultures and CSF cultures confirmed C. neoformans.
Differential diagnosis
Initially, the patient’s hearing loss was thought secondary to typical cerumen impaction. Her slow mentation was attributed to her hearing difficulties as she was able to communicate by writing. On manipulating her head during otoscopic examination, she reacted in severe painful discomfort with neck stiffness. Given that the patient was febrile and physical examination revealed neck stiffness, meningitis was now part of the differential diagnosis.
As the otoscopic examination and CT head were non-revealing and the patient was pyrexic with neck stiffness, a lumbar puncture (LP) was pursued. Her markedly elevated opening pressures were concerning for meningitis, prompting CSF testing for cryptococcal antigen, which returned positive. This led to HIV testing, which confirmed the clinical suspicion of an underlying immunocompromised state.
Treatment
The patient was started on induction therapy for treatment of cryptococcal meningitis with liposomal amphotericin B and flucytosine. Her admission course was prolonged, as she required serial therapeutic lumbar punctures in view of her initial elevated opening pressure.
CD4 count was noted to be 39 cells/UL. The patient reported no prior history of AIDS defining illness or opportunistic infections. She did acknowledge unintentional significant weight loss of 30 pounds over the prior 2 months. The patient was started on azithromycin and atovaquone for Mycobacterium Avium Complex (MAC) and Pneumocystis jirovecii pneumonia (PCP) prophylaxis.
Therapeutic lumbar punctures were performed on days 1, 3, 14, 19 and 22 with corresponding opening pressures of 49, 39, 29, 31 and 19 cmH2O. On each lumbar puncture procedure, CSF was drained to a closing pressure of <20 cmH2O.
Outcome and follow-up
The patient’s hospital course was prolonged as she required serial therapeutic lumbar punctures. Just prior to discharge, repeat lumbar punctures revealed a decreased opening pressure <25 cmH2O. Her hearing deficits returned to near normal over the course of her hospitalisation. The patient was transitioned to consolidation therapy with fluconazole with plans to follow with infectious disease and otology for hearing evaluation.
Discussion
Cryptococcal neoformans is a serious opportunistic infection that occurs in patients with untreated AIDS, usually manifesting as meningitis. Cryptococcal meningitis is always fatal if left untreated, and even with treatment, mortality is up to 40% within 10 weeks.1 The most common symptoms of cryptococcal meningitis include fever, malaise and headache with some patients reporting neck stiffness, photophobia and vomiting. Less commonly reported symptoms include skin rashes, decreased visual acuity and hearing loss. Morbidity and mortality in cryptococcal meningitis are often related to the markedly elevated intracranial pressures which not only manifest with typical meningitis symptoms but can lead to visual loss, hearing loss and death.2
Sensorineural hearing loss has been reported in 27%–30.8% of patients with cryptococcal meningitis.3 The pattern of hearing loss can vary from mild to profound and may present unilaterally or bilaterally.4 Patients reporting acute hearing loss were found to have markedly elevated opening pressures on LP >35 cmH2O.5 Hearing loss is likely caused by infiltration or compression of the vestibulocochlear nerve. Pathologic studies of temporal bones in patients with deafness secondary to cryptococcal meningitis revealed damage to the cochlear nerve due to infiltration with cryptococcal antigens.6 One study reported that moderate/severe mixed hearing loss was common 8 weeks after a diagnosis of cryptococcal meningitis.7
Acute hearing loss can be a presenting feature of cryptococcal meningitis; however, it can also be a complication. Cryptococcal meningitis should be considered in the differential diagnosis of a cause of rapid hearing loss in immunocompromised individuals. Patients with hearing loss associated with cryptococcal meningitis have shown varying degrees of reversibility and as such consideration should be given for formal audiometry assessment in these patients.
Patient’s perspective.
“They kept telling me to go to the doctor when I was losing weight, but I just didn’t bother”
“I got so scared when I went deaf, didn’t realize it was an infection”
Learning points.
To highlight an atypical and lesser detailed symptom of meningitis.
To briefly discuss the underlying pathology of hearing loss associated with cryptococcal meningitis.
To include cryptococcal meningitis as one differential diagnosis of acute bilateral sensorineural hearing loss, particularly in high-risk populations/persons.
Footnotes
Contributors: AAA, NM and MO contributed to acquisition of data and drafting of the manuscript. CLI contributed to acquisition of data, drafting of the manuscript and critical revision of the manuscript.
Funding: The authors have not declared a specific grant for this research from any funding agency in the public, commercial or not-for-profit sectors.
Competing interests: None declared.
Provenance and peer review: Not commissioned; externally peer reviewed.
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