Caracterización clínica de pacientes chilenos con displasia fibrosa/síndrome de McCune-Albright / Clinical features of Chilean patients with Fibrous Dysplasia/McCune-Albright Syndrome

BACKGROUND: Fibrous Dysplasia/McCune-Albright Syndrome (FD/MAS) is characterized by a spectrum of manifestations that may include fibrous dysplasia of bone and multiple endocrinopathies. AIM: To describe the clinical spectrum, the study and follow-up of patients with FD/MAS cared at our institution. MATERIAL AND METHODS: Review of medical records of 12 pediatric and adult patients (11 women) who met the clinical and genetic diagnostic criteria for FD/ MAS. RESULTS: The patients' mean age at diagnosis was 4.9 ± 5.5 years. The most common initial clinical manifestation was peripheral precocious puberty (PPP) in 67% of patients and 75% had café-au-lait spots. Fibrous dysplasia was present in 75% of patients and the mean age at diagnosis was 7.9 ± 4.7 years. Ten patients had a bone scintigraphy, with an age at the first examination that varied between 2 and 38 years of age. The most frequent location of dysplasia was craniofacial and appendicular. No patient had a recorded history of cholestasis, hepatitis, or pancreatitis. In four patients, a genetic study was performed that was positive for the pathogenic variant of guanine nucleotide binding protein, alpha stimulating (GNAS). CONCLUSIONS: These patients demonstrate the variable nature of the clinical presentation and study of FD/MAS. It is essential to increase the index of diagnostic suspicion and adherence to international recommendations.

Observed Frequency and Characteristics of Hearing Loss in Osteogenesis Imperfecta

ABSTRACT Background: Osteogenesis imperfecta (OI) is a rare group of genetic disorders affecting connective tissue, with consequent bone fragility, frequent fractures and skeletal deformity. Depending on the type, patients can have blue sclera, dentinogenesis imperfecta, and hearing loss. Aim: To determine the frequency, type and audiometric characteristics of hearing loss in a group of patients with OI. Material and Methods: A prospective cohort study was completed. A clinical and diagnostic hearing evaluation with tympanometry, acoustic stapedial reflex, pure-tone and speech audiometry were performed. Results: Thirty patients completed the study; mean age of 22 years (range 6-63 years). Sixty seven percent had a type I OI. Overall, nine (30%) patients had hearing loss (15/60 ears). Of these, six had bilateral hearing loss. Of the 15 affected ears, six showed conductive hearing loss, five sensorineural hearing loss, and four mixed hearing loss. Patients with hearing loss were older than patients with normal hearing. Only one pediatric patient developed hearing loss. Of the ears without hearing loss, 13% did not have an acoustic stapedial reflex. Conclusions: In this group of patients with OI, 30% had hearing loss and among those ears with normal hearing, 13% did not have an acoustic stapedial reflex. Patients with OI should be monitored for hearing loss.

Antecedentes: La osteogénesis imperfecta (OI) es un grupo raro de trastornos genéticos que afectan al tejido conectivo, con la consiguiente fragilidad ósea, fracturas frecuentes y deformidad esquelética. Según el tipo, los pacientes pueden presentar escleras azules, dentinogénesis imperfecta e hipoacusia. Objetivos: Determinar la frecuencia, tipo y características audiométricas de la hipoacusia en un grupo de pacientes con OI. Material y Métodos: Se completó un estudio de cohorte prospectivo. Se realizó una evaluación clínica, y de la audición con timpanometría, reflejo estapedial, audiometría tonal y logoaudiometría. Resultados: Treinta pacientes completaron el estudio; edad media de 22 años (rango 6-63 años). El 67% tenía una OI tipo I. Nueve pacientes (30%) tuvieron hipoacusia (15/60 oídos). De estos, seis tenían hipoacusia bilateral. De los 15 oídos afectados, seis tenían hipoacusia de conducción, cinco hipoacusia neurosensorial y cuatro hipoacusia mixta. Los pacientes con hipoacusia eran mayores que los pacientes con audición conservada. Sólo un paciente pediátrico desarrolló hipoacusia. De los oídos sin hipoacusia, el 13% tenía un reflejo estapedial ausente. Conclusiones: En este grupo de pacientes con OI, el 30% tenía hipoacusia. Además, el 13% de los oídos con audición normal no tenía reflejo acústico estapedial. Los pacientes con OI deben ser monitoreados para detectar hipoacusia.