Viral cerebellitis: This condition is characterized by inflammation of the cerebellum, often following a viral infection. The initial presentation of fever followed by cerebellar signs such as ataxia, dysarthria, and nystagmus aligns with the clinical picture of viral cerebellitis. It is a common cause of acute cerebellar ataxia, especially in children.

Bacterial meningitis: Although less common, bacterial meningitis can present with fever and subsequently develop cerebellar signs due to inflammation affecting the cerebellum. The progression of symptoms can sometimes mimic cerebellitis.
Post-infectious cerebellitis: This condition occurs after a viral infection and is thought to be an autoimmune response. It presents similarly to viral cerebellitis but may have a slightly different time course and response to treatment.
Acute disseminated encephalomyelitis (ADEM): ADEM is a rare autoimmune disease characterized by a widespread attack of inflammation in the brain and spinal cord. It can present with fever, followed by neurological signs including cerebellar symptoms, although it typically involves more than one area of the central nervous system.

Brainstem encephalitis: This is an inflammation of the brainstem, which can be life-threatening. Early recognition and treatment are crucial, and it can present with fever and subsequent cerebellar signs among other neurological deficits.
Tuberculous meningitis: Although less common in some regions, tuberculous meningitis can present with fever and neurological signs, including cerebellar involvement. It requires prompt diagnosis and treatment to prevent severe outcomes.
Cerebellar abscess: A cerebellar abscess is a collection of pus in the cerebellum, usually due to a bacterial or fungal infection. It can present with fever, headache, and cerebellar signs, and is a medical emergency requiring urgent neurosurgical intervention.

Subacute sclerosing panencephalitis (SSPE): A rare chronic, progressive encephalitis that affects primarily children and young adults, caused by a persistent infection with the measles virus. It can present with a variety of neurological symptoms, including cerebellar signs, but typically has a more prolonged and progressive course.
Cerebellar vasculitis: Inflammation of the blood vessels supplying the cerebellum can lead to cerebellar signs. This is a rare condition and can be associated with systemic vasculitides or be isolated to the central nervous system.
Lymphoma or metastasis involving the cerebellum: Although rare, these conditions can present with cerebellar signs and may be preceded by systemic symptoms such as fever, especially in the case of lymphoma.