[2] Basophilia can be attributed to many causes and is typically not sufficient evidence alone to signify a specific condition when isolated as a finding under microscopic examination.

As an example, additional evidence of left-shifted neutrophilia alongside basophilia indicates a potential likelihood primarily of chronic myeloid leukemia (CML), or an alternate myeloproliferative neoplasm.

Elevation of basophils may also be representative of multiple other underlying neoplasms such as polycythemia vera (PV), myelofibrosis, thrombocythemia, or, in rare cases, solid tumors.

Since basophilia is present in a vast range of clinical conditions, depending on a variety of underlying causes, supplemental signs and symptoms must be investigated for a diagnosis.

Intrinsically related symptoms such as fever, malaise, pruritus (itching) due to the release of histamine,[5] fatigue, and right upper quadrant pain may be present in the afflicted patient.

Specifically in cases of allergic reactions or associated with chronic inflammation, treating the underlying cause is critical to avoid further, potentially irreparable damage to the body's organ systems.