Ans. c (Splenomegaly is not essential criteria for diagnosis of ITP). (Ref. Harrison 18th/Ch. 115.)IDIOPATHIC THROMBOCYTOPENIC PURPURA# The explosive onset of severe thrombocytopenia following recovery from a viral exanthema or upper respiratory illness {acute ITP) is common in children and accounts for 90% of the pediatric cases of immunologic thrombocytopenia.# Of these patients, 60% recover in 4 to 6 weeks and =90% recover within 3 to 6 months.# Transient immunologic thrombocytopenia also complicates some cases of- Infectious mononucleosis- Acute toxoplasmosis- Cytomegalovirus infection- Prodromal phase of viral hepatitis- Initial infection with HIV# Acute ITP is rare in adults and accounts for = 10% of post-pubertal patients with immune thrombocytopenia.# Most adults present with a more indolent form of thrombocytopenia that may persist for many years and is referred to as chronic ITP.# Women age 20 to 40 are afflicted most commonly and outnumber men by a ratio of 3:1.# These patients have an autoimmune disorder with antibodies directed against target antigens on the glycoprotein (Gp) IIb/IIIa or, less frequently, the Gp Ib/IX complex.# Treatment:- Specific therapy may not be necessary unless the platelet count is <20,000/mL or there is extensive bleeding.- Hemorrhage in patients with either acute or chronic ITP can usually be controlled with glucocorticoids but, in rare cases, may require temporary phagocytic blockade with intravenous immunoglobulin (IVIg) or anti-RhD (WinRho).- Emergency splenectomy is usually reserved for patients with acute or chronic ITP who are desperately ill and have not responded to any medical measures.- Glucocorticoid-responsive but glucocorticoid-dependent patients are very likely to respond to splenectomy, and 70% will have a normal platelet count within 1 week after surgery.- Persistent splenic tissue can be confirmed by a radionuclide scan.- Patients still thrombocytopenic after splenectomy or who relapse months to years after initial therapy have received a variety of immunosuppressive drugs including azathioprine, cyclophosphamide, vincristine, vinblastine, and cyclosporine.- Danazol has also been used with some success.- IVIg and anti-RhD are only transiently effective and expensive.- Rituximab, an anti-CD20 monoclonal antibody used to treat lymphoma, has also proven an effective approach to ITP and is probably preferable to long-term glucocorticoid therapy. Rituximab eliminates normal B cells, including those producing the anti-platelet antibody. This B cell depletion is transient (lasting 12 to 18 months, normally) and has surprisingly few S/E.