Etiologies of hearing loss in Fanconi Anemia

We aim to describe types of hearing loss associated with Fanconi anemia patients who underwent a bone marrow transplant (BMT) to identify possible etiologies of hearing loss. Additionally, we hope to investigate hearing loss early in life as a potential predictor of needing a BMT surgery. Fanconi anemia is a rare autosomal recessive disease that is the most common inherited bone marrow failure syndrome, characterized by bone marrow failure and multiple congenital anomalies, including hearing loss. This is the largest study to date reviewing types of hearing loss in patients with Fanconi anemia, specifically in those who have undergone BMTs.

A retrospective chart review of patients diagnosed with Fanconi anemia at a single institution, tertiary, referral-based children's hospital with a bone marrow transplant team specializing in Fanconi anemia was conducted from 4/19/1976 to 10/19/2015. History, physical examination, audiometry, and imaging findings were reviewed in patients with and without history of bone marrow transplant. Patient hearing levels, as measured by pure tone audiometry at 500 Hz, 1, 2, and 4 kHz, were evaluated. Patients were grouped by transplant status and results and were assessed to determine type and degree of hearing loss. Statistical analysis was performed to compare the likelihood of bone marrow transplant procedures in Fanconi anemia patients with normal and abnormal hearing.

There were 252 patients with Fanconi anemia identified via diagnosis search in institutional electronic medical records using CPT codes and cross referencing with the Fanconi Anemia database, 58 of whom had available audiometric data. Of the 58 Fanconi anemia patients with available audiograms, 21 (36%) had abnormal audiograms; 37 patients had normal audiograms. Twenty out of 21 (95%) patients who had abnormal audiograms had undergone bone marrow transplants. Thirty-one of 37 (84%) patients with normal audiograms had received bone marrow transplants. Statistical analysis showed that patients with hearing loss were more likely to require a BMT in the future (OR = 3.87, p = 0.05). Of the patients with abnormal audiograms and a bone marrow transplant (n = 20), 14 (70%) had conductive hearing loss, 5 (25%) had mixed hearing loss, and 1 patient (5%) had sensorineural hearing loss. 13 of 20 patients (65%) had bilateral hearing loss and eight of 20 (40%) had unilateral hearing loss. Of those patients with conductive hearing loss (n = 15), the most common etiologies were Eustachian tube dysfunction (47%), external auditory canal stenosis (33%), and abnormal middle ear anatomy (13%).

Hearing loss is a common finding in Fanconi anemia patients who have undergone BMTs with conductive hearing loss being the most common audiologic manifestation in our cohort of patients. This demonstrates the necessity of frequent hearing screenings in this population and close collaboration with audiology throughout patient care. Our study indicates that hearing status early in life may be a predictor of needing a bone marrow transplant in the future. Further studies should explore the long-term impact of BMT surgery on hearing status.