The objective of the present study was to evaluate the integrity of the peripheral and central auditory systems of sickle cell disease (SCD) patients, through electrophysiological evaluation utilizing auditory evoked potentials, and comparing the results obtained in SCD patients with individuals without SCD. A total of 80 individuals were evaluated: 40 SCD patients; and 40 healthy age- and sex-matched controls. Brainstem auditory evoked response (BAER) was used to check neural integrity and electrophysiological thresholds, and cognitive potential (P300) to analyse the auditory selective attention. Despite the exclusion of individuals with comorbidities typical of SCD, the predominance of hearing loss among the patients was detected in 16 ears (20%). The absolute latencies of the BAER were within the expected range but the SCD group showed a small but statistically significant reduction of the interpeaks I-V, indicative of cochlear alteration. P300 latency and amplitude were adequate for both groups suggesting the absence of central auditory system abnormalities. The present findings suggest that SCD causes variable degree of cochlear abnormalities without evidence of neural problems.

Fanconi anaemia (FA) is a recessive autosomal disease determined by mutations in genes of at least eleven complementation groups, with distinct distributions in different populations. As far as we know, there are no reports regarding the molecular characterisation of the disease in unselected FA patients in Brazil. Objective: This study aimed to investigate the most prevalent mutations of FANCA and FANCC genes in Brazilian patients with FA. Methods: Genomic DNA obtained from 22 racially and ethnically diverse unrelated FA patients (mean age ± SD: 14.0 ± 7.8 years; 10 male, 12 female; 14 white, 8 black) was analysed by polymerase chain reaction and restriction site assays for identification of FANCA (∆3788-3790) and FANCC (∆322G, IVS4+4A → T, W22X, L496R, R548X, Q13X, R185X, and L554P) gene mutations. Results: Mutations in FANCA and FANCC genes were identified in 6 (27.3%) and 14 (63.6%) out of 22 patients, respectively. The disease could not be attributed to the tested mutations in the two remaining patients enrolled in the study (9.1%). The registry of the two most prevalent gene abnormalities (∆3788-3790 and IVS4 + 4 → T) revealed that they were present in 18.2% and 15.9% of the FA alleles, respectively. Additional FANCC gene mutations were found in the study, with the following prevalence: ∆322G (11.4%), W22X (9.1%), Q13X (2.3%), L554P (2.3%), and R548X (2.3%) of total FA alleles. Conclusion: These results suggest that mutations of FANCA and FANCC genes are the most prevalent mutations among FA patients in Brazil.

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