Administration of IV Laronidase Post Bone Marrow Transplant in Hurler

Number of participants experiencing severe adverse events that occur after administration with Laronidase to determine the feasibility of giving weekly Laronidase

Time frame: 24 months

To determine the feasibility of giving weekly Laronidase for 2 years in patients with Hurler syndrome after allogeneic transplantation, compliance throughout the study with drug administration, the percentage of adherence to the scheduled weekly infusion for each participant is measured.

Time frame: 24 months

Handgrip strength is measured three times in both hands with a mechanical handheld Biodex System 3 dynamometer (Biodex medical Systems, Inc., Shirley, NY) with the subject in a seated position at each visit; the average for each hand is presented.

Time frame: Assessed from baseline every 6 months through 2 years; change between baseline and 24 months reported.If baseline and/or 24-month data were not available, the longest interval between measurements was reported, with a minimum requirement of 12 months

A modified Balke Treadmill Test was performed. Briefly, patients began walking at 2.0 mph with a 2% increase in grade every 2 min. A 12-lead electrocardiogram was monitored continuously throughout the test for the determination of heart rate and dysrhythmias or ischemic changes. Heart rate was measured at the end of each stage (i.e. every 2 min) .

Time frame: Assessed from baseline every 6 months through 2 years; change between baseline and 24 months reported.If baseline and/or 24-month data were not available, the longest interval between measurements was reported, with a minimum requirement of 12 months

difference between baseline and month 24 growth velocities

Time frame: Baseline, Month 24

Population: Baseline growth velocity value was available in six of ten participants. One female participant was excluded from the within-group growth analyses due to a bone age of 14.5 years

6 minute walk test (6MWT) was performed to assess overall physical function and health status. In brief, a 30m hospital corridor marked by colored tape at each end was used. Subjects were instructed to walk from end to end at their self-selected pace, while attempting to cover as much distance as possible in the 6 min. The patients were instructed to walk around the mark as they changed direction. The time and distance covered was recorded, as was the heart rate prior to and immediately after completion of the walk test. To find the association between the rate of change in 6MWT, and anti drug antibody (ADA) titer, a statistical test is performed adjusting for age at the time of enrollment.

Time frame: Assessed from baseline every 6 months through 2 years; change between baseline and 24 months reported.If baseline and/or 24-month data were not available, the longest interval between measurements was reported, with a minimum requirement of 12 months

Bilateral shoulder flexion, elbow extension, and hip extension were measured using goniometry. Improvements are defined for all joints as \>5°.

Time frame: Assessed from baseline every 6 months through 2 years; change between baseline and 24 months reported.If baseline and/or 24-month data were not available, the longest interval between measurements was reported, with a minimum requirement of 12 months

Pulse-wave and color Doppler interrogation of cardiac valves was performed for determination of valve regurgitation

Time frame: Baseline and month 24

Population: Two subjects didn't have both baseline and month 24 echo data

Cardiac ultrasounds were obtained at baseline and month 24. Two-dimensional imaging was obtained for determination of anatomy. Shortening fraction (SF \[normal \> 27%\]) was calculated by standard methods to determine the normal systolic cardiac function

Time frame: Baseline and month 24

Population: two subjects didn't have both baseline and month 24 echo data