Neonatal Thrombocytopenia And Generalized Treatment Of Idiopathic Thrombocytopenic Purpura
A General Overview
Since IgG antibodies cross the placenta, the neonate may develop thrombocytopenia and bleeding. The risk of fetal bleeding during vaginal delivery is high. During delivery or soon after, the fetus may die from intracranial bleeding. Other manifestations are bleeding from the umbilical stump and ecchymosis. Neonatal thrombocytopenia may develop even when the mother is in remission. The majority of infants recover spontaneously. In severe cases, intravenous hydrocortisone 2-3 mg/Kg body weight and platelet transfusions are necessary to tide over the crisis. Since the risk of intracranial bleeding is high during vaginal delivery caesarian section is indicated if the platelet count in the fetus is below 50,000/cmm.
Another cause of neonatal thrombocytopenia is the development of antibodies to fetal platelets. Rh hemolytic disease may also be associated with neonatal thrombocytopenia.
Treating Neonatal Idiopathic Thrombocytopenia Purpura
Acute ITP: Rest in bed is essential to reduce the severity of bleeding. If blood loss is severe, blood transfusion is indicated. Platelet transfusions have been satisfactory in some cases, but when antibody titre is high, the transfused platelets are also destroyed rapidly. Corticosteroids form the mainstay of treatment in the acute stage. Prednisolone given orally in the dosage of 1 to 2 mg/Kg body weight (about 40 mg in divided doses) brings about relief within hours. The effect is brought about by immediate inhibition of macrophage production. The dose is reduced after the first or second week, when clinical severity comes down. Steroids can be withdrawn when the platelet count returns to normal. In fulminant ITP, hydrocortisone or its analogues are given intravenously in a dose equivalent to 100 mg every 8 hours. Steroids should be withdrawn only gradually to avoid exacerbation. In many cases, the remission is permanent. Mild cases of acute ITP may subside spontaneously without specific therapy.
Chronic ITP: As in the case of acute ITP, steroids are started on a moderate dose. Corticosteroids are reintroduced in a dosage necessary to maintain clinical remission, if the platelet count falls on their withdrawal. Steroids are effective in 50-60% of cases.
Splenectomy: Since the spleen is the major source of production of antibody and also platelet destruction, removal of the spleen produces dramatic benefit in over 75% of cases. Following are the indications for splenectomy.
- Acute ITP, non-responsive to corticosteroids- Emergency splenectomy is indicated, especially if there is a danger of intracranial bleeding.
- Chronic ITP in which the bleeding occurs frequently on reduction of steroid dosage below 15 mg/day.
- Exacerbation during pregnancy or when pregnancy is to be allowed in a case of chronic ITP requiring moderate or high doses of corticosteroids.
Soon after splenectomy, the platelet counts and survival shoot up and severe thrombocytosis may lead to thrombotic episodes in the post-operative period. In such cases, antiplatelet drugs and heparin may be necessary. The platelet count gradually returns to normal over weeks and remains so. In some cases, small doses of corticosteroids may be required even after splenectomy. In general, splenectomy is effective in 80% of cases. Splenectomy is not undertaken in children below the age of ten years.
Immunosuppressants: Cyclophosphamide in a dose of 1-2mg/Kg or azathioprine in a dose 1-4 mg/Kg are effective adjuvants when used along with corticosteroids. They are contraindicated in pregnancy. Vincristine in a dose of 1mg/m2 once a week given for three to four weeks helps in bringing about remission in intractable cases.
Newer Drugs: Recently, administration of large doses of gamma-globulin (polyvalent immunoglobulin) in a dose of 0.4ml/Kg has been found to be effective in arresting hemorrhage and improving the platelet count in intractable acute ITP. Probably, this retards platelet destruction by macrophages. Danazol, a non-virilising androgen, has been employed in the management of chronic ITP. All these measures are under trial.
© 2014 Funom Theophilus Makama