Differential Diagnosis

• Single most likely diagnosis
  • Ataxia-Telangiectasia: This diagnosis is highly likely due to the combination of bilateral cerebellar signs, history of clumsiness and delayed motor milestones, history of Hodgkin's lymphoma (indicating immune system dysfunction), and recurrent pneumonia. Ataxia-Telangiectasia is a genetic disorder that affects the nervous system, immune system, and other bodily systems, characterized by cerebellar ataxia, oculocutaneous telangiectasias, immune defects, and a predisposition to cancer.
• Other Likely diagnoses
  • Friedreich's Ataxia: This is another possible diagnosis given the patient's symptoms of ataxia, tremor, and past pointing. However, the presence of a history of cancer and recurrent infections makes Ataxia-Telangiectasia more likely.
  • Ataxia with Oculomotor Apraxia (AOA): This condition presents with ataxia and oculomotor apraxia, but the history of cancer and infections is less commonly associated with AOA compared to Ataxia-Telangiectasia.
• Do Not Miss
  • Metastatic Disease: Given the patient's history of Hodgkin's lymphoma, there is a possibility of metastatic disease affecting the cerebellum, which would be critical to diagnose and treat promptly.
  • Infections (e.g., CNS Lyme disease, Whipple's disease): Certain infections can cause ataxia and other neurological symptoms, and missing these diagnoses could lead to severe consequences if not treated appropriately.
• Rare diagnoses
  • Spinocerebellar Ataxia (SCA) types: There are many types of SCA, each with different genetic causes and varying symptoms. While some SCAs could present similarly, the combination of this patient's symptoms and medical history makes Ataxia-Telangiectasia more likely.
  • Abetalipoproteinemia: This rare genetic disorder affects fat absorption and can lead to neurological symptoms including ataxia, but it is less likely given the patient's overall clinical picture.