A 15-year-old girl comes to the office with gait instability. Since age 12, the patient has had mild weakness and "clumsiness" in her lower limbs that have progressed. She has to hold on to the railing when walking down stairs due to several recent falls. Physical examination reveals kyphoscoliosis, pes cavus, and bilateral lower extremity ataxia. Joint position and vibration sense are also impaired. Further evaluation reveals that she is suffering from an inherited disease. This patient is at greatest risk of dying from which of the following conditions?

Question

A 15-year-old girl comes to the office with gait instability.  Since age 12, the patient has had mild weakness and "clumsiness" in her lower limbs that have progressed.  She has to hold on to the railing when walking down stairs due to several recent falls.  Physical examination reveals kyphoscoliosis, pes cavus, and bilateral lower extremity ataxia.  Joint position and vibration sense are also impaired.  Further evaluation reveals that she is suffering from an inherited disease.  This patient is at greatest risk of dying from which of the following conditions?

Quizplus · Accepted Answer

11ec160b_39bd_e4a7_9249_576d8f536b4b_MD0001_00 This patient likely has Friedreich ataxia, an autosomal recessive condition that typically presents during childhood/adolescence with progressive gait ataxia (due to degeneration of the spinocerebellar tracts) and impaired joint and vibration sense (due to degeneration of the posterior columns and dorsal root ganglia). Lateral corticospinal tract involvement may result in spastic muscle weakness and a positive Babinski sign. Other characteristic features of Friedreich ataxia include hypertrophic cardiomyopathy, skeletal abnormalities (eg, kyphoscoliosis, pes cavus), and diabetes mellitus. Complications from cardiomyopathy (eg, cardiac arrhythmias, congestive heart failure) are the most common cause of death. (Choice A) Marfan syndrome is an autosomal dominant connective tissue disorder associated with aortic dissection, mitral valve prolapse, ectopia lentis, and skeletal findings (eg, pectus excavatum, arachnodactyly, joint hypermobility). (Choice B) Neurofibromatosis types 1 (NF1) and 2 (NF2) are autosomal dominant disorders. NF1 is associated with optic gliomas, whereas NF2 is associated with bilateral acoustic schwannomas and meningiomas. (Choices D and F) Autosomal dominant polycystic kidney disease usually presents in adults and is associated with hypertension, renal failure, and intracranial bleeding due to ruptured Berry aneurysms. (Choice E) Wilson disease (hepatolenticular degeneration) is an autosomal recessive disorder associated with liver failure, movement abnormalities, and psychiatric symptoms. Educational objective: Friedreich ataxia is an autosomal recessive condition that presents during childhood/adolescence with progressive gait ataxia (due to degeneration of the spinocerebellar tracts) and impaired joint and vibration sense (due to degeneration of the posterior columns and dorsal root ganglia). Other features include hypertrophic cardiomyopathy (most common cause of death), skeletal abnormalities (eg, kyphoscoliosis, pes cavus), and diabetes mellitus. __________ References: Clinical features of Friedreich's ataxia: classical and atypical phenotypes. (http://www.ncbi.nlm.nih.gov/pubmed/23859346)

A 15-Year-Old Girl Comes to the Office with Gait Instability