Application of a glycinated bile acid biomarker for diagnosis and assessment of response to treatment in Niemann-pick disease type C1.

Niemann-Pick disease type C (NPC) is a neurodegenerative disease in which mutation of NPC1 or NPC2 gene leads to lysosomal accumulation of unesterified cholesterol and sphingolipids. Diagnosis of NPC disease is challenging due to non-specific early symptoms. Biomarker and genetic tests are used as first-line diagnostic tests for NPC. In this study, we developed a plasma test based on N-(3ß,5α,6ß-trihydroxy-cholan-24-oyl)glycine (TCG) that was markedly increased in the plasma of human NPC1 subjects. The test showed sensitivity of 0.9945 and specificity of 0.9982 to differentiate individuals with NPC1 from NPC1 carriers and controls. Compared to other commonly used biomarkers, cholestane-3ß,5α,6ß-triol (C-triol) and N-palmitoyl-O-phosphocholine (PPCS, also referred to as lysoSM-509), TCG was equally sensitive for identifying NPC1 but more specific. Unlike C-triol and PPCS, TCG showed excellent stability and no spurious generation of marker in the sample preparation or aging of samples. TCG was also elevated in lysosomal acid lipase deficiency (LALD) and acid sphingomyelinase deficiency (ASMD). Plasma TCG was significantly reduced after intravenous (IV) 2-hydroxypropyl-ß-cyclodextrin (HPßCD) treatment. These results demonstrate that plasma TCG was superior to C-triol and PPCS as NPC1 diagnostic biomarker and was able to evaluate the peripheral treatment efficacy of IV HPßCD treatment.

Application of N-palmitoyl-O-phosphocholineserine for diagnosis and assessment of response to treatment in Niemann-Pick type C disease.

Niemann-Pick type C (NPC) disease is a rare lysosomal storage disorder caused by mutations in either the NPC1 or the NPC2 gene. A new class of lipids, N-acyl-O-phosphocholineserines were recently identified as NPC biomarkers. The most abundant species in this class of lipid, N-palmitoyl-O-phosphocholineserine (PPCS), was evaluated for diagnosis of NPC disease and treatment efficacy assessment with 2-hydroxypropyl-ß-cyclodextrin (HPßCD) in NPC. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) methods were developed and validated to measure PPCS in human plasma and cerebrospinal fluid (CSF). A cutoff of 248 ng/mL in plasma provided a sensitivity of 100.0% and specificity of 96.6% in identifying NPC1 patients from control and NPC1 carrier subjects. PPCS was significantly elevated in CSF from NPC1 patients, and CSF PPCS levels were significantly correlated with NPC neurological disease severity scores. Plasma and CSF PPCS did not change significantly in response to intrathetical (IT) HPßCD treatment. In an intravenous (IV) HPßCD trial, plasma PPCS in all patients was significantly reduced. These results demonstrate that plasma PPCS was able to diagnose NPC1 patients with high sensitivity and specificity, and to evaluate the peripheral treatment efficacy of IV HPßCD treatment.

Prominent forehead hematomas ("goose-eggs") as an initial manifestation of hemophilia.

Prominent forehead hematomas, "goose-eggs," may suggest an underlying disorder of coagulation. We reviewed records of 324 children with hemophilia and confirmed that a goose-egg was the presenting feature leading to a diagnosis of hemophilia in 14 of them. Primary care providers should be aware of this unique presentation of hemophilia.

Intravenous low molecular weight iron dextran in children with iron deficiency anemia unresponsive to oral iron.

BACKGROUND: Iron deficiency anemia (IDA) in children is usually treated with oral iron, yet many respond poorly. Intravenous low molecular weight iron dextran (LMWID) offers the opportunity of employing a single outpatient infusion to correct the anemia and reduce the overall burden of treatment, but its use in children has been limited due to concerns of serious adverse effects. In this study we report our initial experience using LMWID in children with iron deficiency in whom oral iron was ineffective. METHODS: We performed a case series of LMWID treatment of children with IDA of diverse etiologies who were poorly responsive to oral iron therapy with the aim of measuring its efficacy and adverse effects. LMWID was administered as a total dose infusion over 60 minutes in the outpatient setting. RESULTS: Thirty-one patients age 11 months to 18 years received intravenous LMWID, and 24 were evaluable for hematologic response. Median hemoglobin increments were respectively 3.5, 1.9, and 1.8 g/dl in patients with IDA due to poor nutrition (n = 11), chronic blood loss (n = 13), and miscellaneous causes (n = 7). Two thirds of evaluable patients had a complete hematologic response. Nine of the patients (29%) had mild non-specific adverse effects upon initiation of the LMWID infusion. CONCLUSIONS: LMWID as a total dose infusion was well tolerated and effective in a heterogeneous group of children and adolescents with IDA who were refractory to oral iron therapy. Transient reactions were common but not serious.

131I-MIBG followed by consolidation with busulfan, melphalan and autologous stem cell transplantation for refractory neuroblastoma.

BACKGROUND: (131) I-metaiodobenzylguanidine (MIBG) produces a 37% response rate in relapsed/refractory neuroblastoma, and could be used to improve remission status prior to myeloablative chemotherapy with autologous stem cell transplant (ASCT). The purpose of our report was to evaluate safety and response with MIBG therapy followed by myeloablative busulfan and melphalan (BuMel) with ASCT in patients with refractory neuroblastoma. METHODS: Retrospective chart review was done on patients treated with MIBG (18 mCi/kg) on Day 1 and ASCT on day 14. Six to eight weeks after MIBG, patients without progressive disease received IV busulfan on days -6 to -2 (target Css 700-900), melphalan (140 mg/m2 IV) on day -1, and ASCT on Day 0. Response and toxicity were evaluated after MIBG and again after myeloablative therapy. RESULTS: Eight patients completed MIBG/ASCT followed by BuMel/ASCT. MIBG was well tolerated, with grade 3 or 4 non-hematologic toxicity limited to one patient with sepsis. Grade 3 mucositis occurred in six patients after BuMel/ASCT. One patient developed sinusoidal obstructive syndrome (SOS) and died 50 days post-ASCT following myeloablative conditioning. All patients engrafted neutrophils (median 16.5 days) and platelets (median 32 days) after BuMel, excluding the patient with SOS. After all therapy, there were three complete, two partial, and one minor response in seven evaluable patients. CONCLUSIONS: MIBG at doses up to 18 mCi/kg can be safely administered 6 weeks prior to a BuMel consolidative regimen for refractory neuroblastoma. Preceding MIBG did not impair engraftment following BuMel. This regimen is being further evaluated in a Children's Oncology Group (COG) trial.