FIRST DO NOT HARM !

For pediatricians and hematologists both, idiopathic thrombocytopenic purpura (ITP) is encountered very commonly. We would not be misplaced if we state that even though it is common, it is the most commonly mismanaged condition. And both pediatricians and hematologists must shoulder the blame! The urge to treat a child with ITP whenever the platelet count is less than 1,50,000/cmm is the underlying reason for mismanagement in most cases. We would like to point out that abnormal platelet counts always require explanation but not necessarily treatment. It should be remembered that platelets in ITP are young cells due to increased production and hence carry a significantly less risk of hemorrhage. In this sense, thrombocytopenia in a child with aplastic anemia is more dangerous than in child with ITP. It is prudent to consider thrombocytopenia as a physical sign than a clinical problem. It is only with platelet counts below 10-20,000/cmm that hemorrhagic problems regularly occur. As a corollary to this, all children with platelet count above 20,000/cmm in ITP (acute or chronic) do not demand any short of intervention at all.

Now we should be careful with the platelet counts estimation as well. Unless carried out by automated, quality controlled, reliable instruments the platelet count should be taken with a pinch of salt. The gold standard would be an estimate by manual phase contrast microscopy. And of course, the peripheral smear examination should confirm the platelet count estimation. Spurious results with automated cell counters should be ruled out. Reliable platelet counts are necessary for the follow up of a child with ITP but we suggest that clinicians should focus on the child and not the platelet count for treatment decisions. The reason: spontaneous bleeding cannot be predicted by platelet count alone in ITP. Therefore, clinical assessment at the bedside is most crucial.

In children with acute ITP, what should be the pragmatic approach in view of the above facts? We have often seen a child with acute ITP and mild symptoms and platelet count above 20,000/cmm treated with 2 gm/kg IV immunoglobulins. Or another child with similar presentation treated with high dose oral or intravenous steroids for 3-6 months or longer. It is certain that both these approaches are inappropriate in view of the natural history of acute childhood ITP. Acute childhood ITP is usually self-limiting with spontaneous recovery in 90% of cases in less than 3 to 6 months from the onset. Moreover, the severity of thrombocytopenia does not correlate with the long-term outlook of recovery. Neither does any therapeutic intervention change this natural course in a given child.

Hence the bottom line is: Children with mild ITP irrespective of their platelet counts need not be treated. Those with severe bleeding symptoms and very low platelet counts may transiently benefit from use of steroids or IVIG. Guidelines for the therapy of ITP have been drawn up for children in the UK(1) and for children and adults in the USA(2).

The distinction between acute and chronic ITP is based entirely on whether the condition persists for over 6 months or not. Here, again late remission is extremely common in children and can arise as late as 5 to 19 years after diagnosis! For the few children who do not remit, therapies other then steroids, and IVIG may be considered. But before any are third, it is important to consider whether the child has any symptoms of the disease. If not and if the platelet count is more than 20,000/cmm, it is unlikely that the cost, inconvenience or risk of any treatment is justified. Chronic ITP in children is usually a benign condition, which does not require specific treatment and may remit at any time. The advice for splenectomy, especially in children with chronic ITP must come after great consideration. It is unfortunate for children with ITP that splenectomy is regarded by hematologists as a treatment of choice in adults with chronic ITP refractory to steroids. This thinking has lead to many referrals for consideration of splenectomy if child has not remitted within six months (3).

There are several reasons for this recommendation to withhold splenectomy for as long as possible: firstly, severe thrombocytopenia with mild symptoms is entirely compatible with normal activities and longevity (4); secondly, late and long term remissions in childhood chronic IPT are common (5); thirdly, the risk of post-splenectomy sepsis and mortality is probably more than the risk of serious bleeding from the disease. Despite the hazards of the splenectomy, it may be justified only in the symptomatic children with profound thrombocytopenia of more than at least 2 years duration. We should remember that any form of treatment in chronic ITP including splenectomy is only symptomatic rather than curative. Given the low mortality of this benign condition and chances of spontaneous remission, a careful analysis of risks and benefits of treatment is essential.

Probably, the most important factor in dealing with the child with ITP is the attitude of the treating clinician. The treatment should be directed at the patient rather than at the platelet count. The natural history and the risks and the benefits of treatment options must be discussed in detail with the child's family. And the adage: "First do not harm!" must never be forgotten by the clinician.

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