Over a year after IVIG infusions ended, the patient had an elevated IgG level of 4,000 mg/dL. DR. WANG
CARMEL, CALIF. — A complication involving monoclonal gammopathy in a child who received cord blood for treatment of Chédiak-Higashi syndrome may be the first of its kind, Dr. Kevin Wang said at the Western regional meeting of the American Federation for Medical Research.
Dr. Wang, a visiting fellow in the department of pediatrics at the University of California, Los Angeles, Medical Center, discussed what is believed to be the first reported case of monoclonal gammopathy in a young boy following cord blood transplantation.
At 16 months of age, the boy was diagnosed with Chédiak-Higashi syndrome (CHS), but his parents declined bone marrow transplantation at that time. At age 2 years, he was started on granulocyte colony-stimulating factor for neutropenia and remained stable for the next 4 years.
At age 6 years, the boy presented to Dr. Wang and his associate, Dr. Robert L. Roberts, with pancytopenia, fever, respiratory distress, mental status changes, seizure activity, and hepatosplenomegaly.
Dr. Wang and Dr. Roberts determined that the boy was in the accelerated phase of CHS. Bone marrow biopsy showed cytoplasmic inclusions, granulocytes, and hemophagocytic cells. Brain MRI showed nonspecific focal hyperintensities in the white matter, which is consistent with lymphohistiocytic infiltration.
The boy received three courses of IV immunoglobulin (IG), then methylprednisolone for 10 days, and dexamethasone for 2 months, after which he remained on a maintenance dose of dexamethasone until the time of splenectomy that was necessitated by persistent thrombocytopenia. Over the next several weeks, the boy's condition improved.
A repeat bone marrow biopsy revealed rare hemophagocytic cells and a repeat MRI showed significant improvement, suggesting that he was in remission from the accelerated phase. Dr. Wang reported that the boy then received a 10/10 match cord blood transplantation. He appeared to engraft successfully, leading to discontinuation of his routine infusions of IVIG. About 15 months later, the boy was clinically stable but he had an elevated IgG level of 4,000 mg/dL. Immunoelectrophoresis revealed that he had developed a monoclonal IgG gammopathy.
“The patient is clinically stable but he is being monitored closely for the risk of developing lymphoma,” Dr. Wang said.