In cardiovascular disease, increased white blood cell counts have been shown to indicate a worse prognosis.

An increase in eosinophil granulocyte is known as eosinophilia.

Granulocytosis can be a feature of a number of diseases:

- Infection, especially bacterial

- Malignancy, most notably leukemia (it is the main feature of chronic myelogenous leukemia, CML)

- Autoimmune disease

Diagnostic testing in a possible paraneoplastic syndrome depends on the symptoms and the suspected underlying cancer.

Diagnosis may be difficult in patients in whom paraneoplastic antibodies cannot be detected. In the absence of these antibodies, other tests that may be helpful include MRI, PET, lumbar puncture and electrophysiology.

Treatment options include:

1. Therapies to eliminate the underlying cancer, such as chemotherapy, radiation and surgery.

2. Therapies to reduce or slow neurological degeneration. In this scenario, rapid diagnosis and treatment are critical for the patient to have the best chance of recovery. Since these disorders are relatively rare, few doctors have seen or treated paraneoplastic neurological disorders (PNDs). Therefore, PND patients should consult with a specialist with experience in diagnosing and treating paraneoplastic neurological disorders.

A specific prognosis for those afflicted with paraneoplastic syndromes links to each unique case presented. Thus, prognosis for paraneoplastic syndromes may vary greatly. For example, paraneoplastic pemphigus often included infection as a major cause of death. Paraneoplastic pemphigus is one of the three major subtypes that affects IgG autoantibodies that are characteristically raised against desmoglein 1 and desmoglein 3 (which are cell-cell adhesion molecules found in desmosomes). Underlying cancer or irreversible system impairment, seen in acute heart failure or kidney failure, may result in death as well.