Differential Diagnosis
The patient's presentation suggests a neurological condition affecting her motor skills, balance, and bladder control. Here's a categorized differential diagnosis:
- Single most likely diagnosis
- B. Atlantoaxial instability: This condition is common in patients with Down syndrome due to ligamentous laxity and can cause spinal cord compression, leading to ataxia, decreased muscle tone, hyperreflexia, and urinary incontinence.
- Other Likely diagnoses
- C. Hypothyroidism: Hypothyroidism is prevalent in individuals with Down syndrome and can cause ataxia, muscle weakness, and decreased coordination.
- E. Tethered cord syndrome: Although less common, tethered cord syndrome can cause similar symptoms, including ataxia, muscle weakness, and urinary incontinence, due to spinal cord tethering.
- Do Not Miss
- D. Spinal cord infarction: Although rare, spinal cord infarction can present with sudden onset of symptoms, including ataxia, muscle weakness, and urinary incontinence. It's essential to consider this diagnosis to provide timely and appropriate treatment.
- Rare diagnoses
- A. Alzheimer disease: Alzheimer's disease is unlikely in a 6-year-old child, even with Down syndrome, as it typically presents in much older individuals.
- Other rare conditions, such as spinal tumors or infections, could also be considered, but they are less likely given the patient's presentation and the absence of other symptoms like fever or weight loss.
It's essential to conduct further evaluation, including imaging studies (e.g., MRI), to confirm the diagnosis and guide treatment.