Worn-out Tip Shoes as a Clue for a Family Genetic Diagnosis

Background: Gait abnormalities and muscle weakness can be the presentation of different conditions, namely inflammatory, infectious, traumatic or degenerative diseases. The etiology is not always easy to define, as the findings of the physical exam can be nonspecific to a general pediatrician, such as lower limb hypertonia and orthopedic deformities. Therefore, it is fundamental to perform a detailed interview and physical exam.

Clinical case: A previously healthy, 11-years old male was observed in a general pediatrics appointment due to pain referred to the feet, muscle weakness, and progressive difficulties to walk associated with worn-out tip shoes. No sphincter complaints. Family history of an uncle and grandfather with similar symptoms, but no definitive diagnosis. General physical examination was normal. He had normal cognitive development, but showed lower limb increased osteotendinous reflexes, and discrete cavus feet. Routine laboratory findings were normal. At this point, the adolescent was referred to a Neuropediatric center. Neurologic evaluation revealed a spastic paraplegia, lower limbs hyperreflexia with right ankle clonus and bilateral Babinski. Brain and medulla magnetic resonance imaging were normal. Further investigation included a hereditary spastic paraplegia (SPG) genetic panel, which allowed the identification of a pathogenic gene mutation, on BSCL2 gene (SPG 17), which is associated with a dominant type of SPG. He is under physiotherapy treatment, and two years after diagnosis, he manages to walk independently.

Discussion: Hereditary spastic paraplegia is a syndromic designation for a clinically and genetically heterogeneous group of inherited neurodegenerative disorders, in which the main neurological symptoms and signs are lower limb spasticity and weakness. In childhood, the most prevalent are SPG 3 and 4. Clinicians should be aware of this diagnosis, especially when combining both clinical symptoms/signs with similar familiar history. Despite the positive family history, this was the first case with a genetic diagnosis, allowing family genetic counseling.