Idiopathic thrombocytopenic purpura: a practice guideline developed by explicit methods for the American Society of Hematology [see comments]

Abstract

DIOPATHIC thrombocytopenic purpura (ITP, also I known as primary immune thrombocytopenic purpura) is a hematologic disorder for which appropriate diagnostic and treatment strategies are uncertain. In 1994, the American Society of Hematology (ASH) established a panel to produce explicitly developed practice guidelines for the diagnosis and management of ITP. "Explicitly developed," evidencebased practice guidelines, which are being issued increasingly by medical specialty societies, combine a critical appraisal of scientific evidence with practice recommendations that state clearly to what extent the guidelines are based either on published scientific evidence or opinion (eg, clinical experience).I4 More details about the clinical practice guideline movement are provided elsewhere.'.' This report begins with a brief summary of the panel's recommendations, followed by a more detailed analysis of its methodology, the findings of the comprehensive literature review, and a full presentation of the recommendations. The report concludes with recommendations for future research. As explained later, the recommendations are based on the panel's opinion, derived from a systematic scoring methodology. (Only recommendations receiving scores of 1 .O to 3.0 or 7.0 to 9.0, as defined later in the text, are cited in this summary.)

Pathobiology of Secondary Immune Thrombocytopenia

“…Several hundred therapeutic agents have been implicated, 156 but few reports are compelling. 157 The diagnosis of DITP is generally based on this clinical scenario: (1) therapy with a candidate drug precedes thrombocytopenia by sufficient time to develop antibody; (2) there is no such temporal relationship with another drug; (3) all other reasonable causes have been excluded; (4) recovery occurs upon the discontinuation of the drug; and (5) re-exposure to the drug, if attempted, leads to recurrent thrombocytopenia. However, these criteria are rarely met, as underlying clinical circumstances are often complex and introduction and withdrawal of multiple drugs within a short time frame is common.…”

Antiphospholipid antibodies in immune thrombocytopenic purpura tend to emerge in exacerbation and decline in remission

“…We studied 40 patients with ITP, comprising 22 females and 18 males aged 20-82 years (mean 51AE8 years). All met the diagnostic criteria of ITP (George et al, 1996), characterized by chronic thrombocytopenia in the absence of splenomegaly without identifiable underlying disorders and an increased number of megakaryocytes in the bone marrow. Thrombocytopenia was present for over 6 months.…”

Hepatitis C virus‐related thrombocytopenia: clinical and laboratory characteristics compared with chronic immune thrombocytopenic purpura

“…The American Society of Hematology (ASH) expert panel has defined chronic immune thrombocytopenic purpura (CITP) as isolated thrombocytopenia in patients with no clinical conditions that can cause thrombocytopenia (George et al, 1996). Infection with human immunodeficiency virus (HIV), systemic lupus erythematosis, antiphospholipid antibody syndrome, lymphoproliferative disorders, myelodysplasia, liver disease with portal hypertension, drug therapy and hereditary thrombocytopenia are well recognized causes which need to be excluded prior to diagnosis of CITP (George et al, 1996).…”

“…The American Society of Hematology (ASH) expert panel has defined chronic immune thrombocytopenic purpura (CITP) as isolated thrombocytopenia in patients with no clinical conditions that can cause thrombocytopenia (George et al, 1996). Infection with human immunodeficiency virus (HIV), systemic lupus erythematosis, antiphospholipid antibody syndrome, lymphoproliferative disorders, myelodysplasia, liver disease with portal hypertension, drug therapy and hereditary thrombocytopenia are well recognized causes which need to be excluded prior to diagnosis of CITP (George et al, 1996). Thrombocytopenia has also been described in association with hepatitis C virus (HCV) infection (Pawlotsky et al, 1995;Linares et al, 1996;Nagamine et al, 1996;Pivetti et al, 1996;Kosugi et al, 1997;Hernandez et al, 1998;Garcia-Suarez et al, 2000;Sakuraya et al, 2002) and may be present even in the absence of clinically evident liver disease or splenomegaly (Linares et al, 1996;Nagamine et al, 1996;Pivetti et al, 1996;Hernandez et al, 1998;Garcia-Suarez et al, 2000).…”