Immune thrombocytopenic purpura (ITP) may occur in conjunction with a number of conditions. A diagnosis of idiopathic or primary ITP can be made ONLY if all of these diagnoses have been ruled out.
Systemic autoimmune disease:
(1) systemic lupus erythematosus (SLE)
(2) ulcerative colitis (UC)
(3) Sjogren' syndrome
Hematologic neoplasm or preneoplasm:
(1) B-cell malignant lymphoma
(2) myelodysplastic syndrome (MDS)
(3) chronic lymphocytic leukemia (CLL)
Carcinoma:
(1) malignant melanoma
(2) prostate adenocarcinoma
(3) pancreatic adenocarcinoma
(4) sarcomatoid carcinoma
Infection:
(1) cytomegalovirus (CMV)
(2) viral hepatitis C (HCV) and viral hepatitis B (HBV)
(3) human immunodeficiency virus (HIV)
(4) infectious mononucleosis (EBV)
(5) other viral infection (rubella, parvovirus B19, mumps, varicella, etc)
(6) Helicobacter pylori
Drug-related:
(1) adalimumab
(2) immune drug reaction
Some patients with an underlying cause may present with ITP prior to the diagnosis of the disorder. Therefore, a diagnosis of primary ITP requires a follow-up period during which there is monitoring for a previously occult disorder.
In a patient with a carcinoma it is important to exclude a chronic DIC before a diagnosis of ITP is made.
