Table 2.

Demographic and clinical data for 14 HbSC patients treated with hydroxyurea between 2007 and 2014 at the Texas Children's Hospital Hematology Center.

Patient no.	Age at HU start (years)	Gender	Indications for hydroxyurea	Adverse events	Splenomegaly	HU starting dose (mg/kg)	HU dose at MTD (mg/kg)	Clinical course
1	10.60	M	Pain	Neutropenia	Yes	20	20.2	Reduction in pain events
2	12.88	M	Pain	Abdominal pain	No	19	Not reached	Unable to assessb
3	9.02	M	AVN	None	No	20	23.5	AVN resolved
4	5.67	F	ACS, Pain	None	No	21	Not reached	Unable to assessb
5	7.25	M	Pain	Thrombocytopenia,	No	20a	15.6	Reduction in pain events
6	9.91	M	Pain	Thrombocytopenia, abdominal pain	Yes	20a	9.5	Reduction in pain events on dual therapy
7	9.90	M	Pain	Thrombocytopenia	No	20a	10	Reduction in pain events
8	11.46	M	Pain	None	No	20a	17	No improvement in pain events
9	18.18	M	Retinopathy	Thrombocytopenia	No	18	18	Stabilization of retinopathy on dual therapy
10	7.71	F	Pain, Retinopathy	Neutropenia, thrombocytopenia GI bleed	Yes	15a	12.7	Stabilization of retinopathy on dual therapy; no improvement in pain events
11	14.25	M	Pain, AVN	Thrombocytopenia	Yes	14	18	50% reduction in chronic narcotic use on dual therapy
12	11.62	M	ACS, pain	None	No	20	20	Reduction in pain events
13	12.00	M	Pain, ACS	None	Yes	14	Not reached	Unable to asssesb
14	12.84	M	Pain, ACS	None	Yes	15	17.6	Reduction in pain events

ACS, acute chest syndrome; AVN, avascular necrosis; MTD, maximum tolerated dose, as defined in text.

Dual therapy refers to the combination of hydroxyurea dosed to MTD and phlebotomy with a goal Hb of 9.5–10 g/dL.

^aSome patients achieved MTD at doses below their starting dose.

^bUnable to assess effect of hydroxyurea on clinical course if MTD was not reached.