Urinary Homovanillic Acid Research Articles

Establishment and clinical application of a candidate reference measurement procedure for quantification of urinary vanillylmandelic acid and homovanillic acid using ID-LC-MS/MS method

Neuroblastoma (NB), an embryonic tumor of the autonomous nervous system, poses a significant threat to the health and lives of children. Accurate measurement of vanillylmandelic acid (VMA) and homovanillic acid (HVA) in human urine is crucial for screening and diagnosis of NB. Although various laboratories have developed liquid chromatography tandem mass spectrometry (LC-MS/MS) method to detect VMA and HVA, the comparability between the results obtained from different laboratories and methods was poor. The absence of reference method for VMA and HVA hinders the standardization of their measurements. Therefore, a candidate reference measurement procedure (cRMP) based on isotope dilution LC-MS/MS (ID-LC-MS/MS) for the detection of VMA and HVA in human urine was established. Urine samples were spiked with VMA-d3 and HVA-d5 as internal standards and extracted using a protein precipitation method. The cRMP exhibited desirable precision with the total imprecision below 5 %. The accuracy of this cRMP was demonstrated by the high analytical recovery (98.64 % - 102.22 % and 98.41 % - 100.97 % for VMA and HVA, respectively), and comparability between different reference systems. The limit of detection for HVA and VMA were 15.625 ng/mL and 3.906 ng/mL, respectively; the quantification limits were 62.5 ng/mL and 7.813 ng/mL, respectively, which can meet the clinical detection requirements. The linear range was from 78.125 ng/mL to 20 μg/mL. Specificity evaluations showed no corresponding interference from structurally similar analogs. In conclusion, we have established a cRMP based on ID-LC-MS/MS for the measurement of VMA and HVA in urine samples, demonstrating well-defined method performance including accuracy, precision, and specificity. This newly established cRMP is suitable for routine assay standardization and evaluation of clinical samples. Furthermore, this method has the potential to significantly enhance the diagnostic accuracy for neuroblastoma.

Analytical method for urinary homovanillic acid and 5-hydroxyindoleacetic acid levels using HPLC with electrochemical detection applied to evaluate children environmentally exposed to manganese.

Homovanillic acid (HVA) and 5-hydroxyindoleacetic acid (5-HIAA) are the urinary metabolites of dopamine (DA) and serotonin (5-HA), respectively. We aimed to develop an extraction method for the determination of HVA and 5-HIAA, using strong anionic exchange cartridges combined with HPLC with electrochemical detection, and apply it to measure the levels of HVA and 5-HIAA in children living near a ferro-manganese alloy plant in Simões Filho, Brazil. The validated method showed good selectivity, sensitivity, precision, and accuracy. The limits of detection (LOD) were 4 and 8 μmol/L for 5-HIAA and HVA, respectively, in urine. Recoveries ranged from 85.8 to 94%. The coefficients of determination (R2 ) of the calibration curves were greater than 0.99. Spot urine samples of 30 exposed children and 20 nonexposed ones were processed accordingly. The metabolite levels in exposed and reference children were within the physiological ranges. The medians (range) for 5-HIAA and HVA of the exposed ones were 36.4 μmol/L (18.4-58.0) and 32.9 μmol/L (<LOD-91.9), respectively. There was no significant difference between the values presented by children in the reference group: 25.7 μmol/L (19.9-81.4) and 35.2 μmol/L (<LOD-67.6) for 5-HIAA and HVA, respectively. These results suggest that the quantification of the urinary metabolites possibly does not reflect the interference of manganese in the metabolism of DA and 5-HA in the central nervous system.

Abstract 2199: Novel urinary marker for diagnosis and prognosis of neuroblastoma

Abstract Background and Aim: Urinary homovanillic acid (HVA) and vanillylmandelic acid (VMA) concentrations are widely used for diagnosis of neuroblastomas, which are catecholamine-secreting tumors. As recent advances in mass spectrometry have facilitated the measurement of metabolites present at extremely low concentrations, urinary metabolites with better diagnostic or prognostic utility for detection of neuroblastomas could be identified. This study utilized quantitative analyses using liquid chromatography-mass spectrometry (LC-MS) to evaluate the diagnostic and prognostic performance of a novel biomarker candidate: 3-methoxytyramine sulfate [3-MTS]. Materials and Methods: The concentrations of the three urinary metabolites (HVA, VMA, and 3-MTS) in urine samples of 41 patients with primary neuroblastoma and urine samples of 155 control participants were measured using LC-MS. The cut-off values for these metabolites were the mean + 2 standard deviation values of the control. Linear discriminant analysis was used to evaluate the association of urinary marker candidates with unfavorable risk factors such as the International Neuroblastoma Pathology Classification and MYCN amplification. Results: The sensitivity and specificity were as follows: 3-MTS 90.2%, 94.2%; HVA 87.8%, 96.1%; VMA 87.8%, 96.1%; VMA or HVA+3-MTS 97.6%, 92.3%; HVA+VMA 87.8%, 94.8%; respectively. 3-MTS could differentiate between the cases with favorable and unfavorable histology (AUC =0.950). 3-MTS+VMA differentiated between the cases with MYCN amplification and nonamplification (AUC=0.952). Conclusions: 3-MTS might be a useful urine marker for both diagnosis and prognosis of neuroblastoma. Citation Format: Akinari Hinoki, Hizuru Amano, Hiroo Uchida, Atsushi Narita, Shun Kumano, Mayumi Abe, Minoru Sakairi, Chiyoe Shirota, Wataru Sumida, Satoshi Makita, Yoshiyuki Takahashi, Tsuyoshi Osawa. Novel urinary marker for diagnosis and prognosis of neuroblastoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 2199.

Metal organic framework-based tricolor fluorescence imprinted sensor for rapid intelligent detection of homovanillic acid

Homovanillic acid (HVA) is one of the main metabolites of catecholamines in the body. Abnormal levels of HVA in urine and serum are associated with neuroblastoma and Parkinson's disease. Herein, a smartphone-assisted tricolor fluorescence imprinted sensor was proposed with one-pot synthesis strategy for the intelligent determination of HVA in serum and urine. In this study, luminescent metal–organic framework was used as reference probe, while green-emitting CdTe and red-emitting CdTe were used as response probes. With increasing HVA concentration, the green-emitting CdTe and red-emitting CdTe fluorescence were gradually quenched, while the blue fluorescence of metal–organic framework remained stability. The tricolor fluorescence imprinted sensor extends the color variations range for visual detection with dynamic detection range (0.05–180 µM). The fluorescence imprinted sensor exhibits a lower detection limit of 15 nM and rapid response within 2 min. Interestingly, a portable smart sensing platform was designed by integrating the tricolor fluorescence imprinted polymer and a smartphone assisted device to achieve on-site accurate analysis HVA with a detection limit of 34 nM. The sensing platform was applied to in situ monitoring of HVA in serum and urine with satisfactory results, providing a new method for visual intelligent detection of HVA.

Chronic Diarrhea and Weight Loss in an 18-month-old Boy.

Chronic Diarrhea and Weight Loss in an 18-month-old Boy.

Application of an LC-MS/MS Method for the Simultaneous Quantification of Homovanillic Acid and Vanillylmandelic Acid for the Diagnosis and Follow-Up of Neuroblastoma in 357 Patients.

Homovanillic acid (HVA) and vanillylmandelic acid (VMA) are end-stage metabolites of catecholamine and are clinical biomarkers for the diagnosis of neuroblastoma. For the first time in Korea, we implemented and validated a liquid chromatography tandem mass spectrometry (LC–MS/MS) assay to measure urinary concentrations of HVA and VMA according to Clinical and Laboratory Standards Institute guidelines. Our LC–MS/MS assay with minimal sample preparation was validated for linearity, lower limit of detection (LOD), lower limit of quantification (LLOQ), precision, accuracy, extraction recovery, carryover, matrix effect, and method comparison. A total of 1209 measurements was performed to measure HVA and VMA in spot urine between October 2019 and September 2020. The relationship between the two urinary markers, HVA and VMA, was analyzed and exhibited high agreement (89.1% agreement, kappa’s k = 0.6) and a strong correlation (Pearson’s r = 0.73). To our knowledge, this is the first study to utilize LC–MS/MS for simultaneous quantitation of spot urinary HVA and VMA and analyze the clinical application of both markers on a large scale for neuroblastoma patients.

Blood, urine and cerebrospinal fluid analysis in TH and AADC deficiency and the effect of treatment

BackgroundAromatic L-amino acid decarboxylase (AADC) deficiency and tyrosine hydroxylase (TH) deficiency are rare inherited disorders of monoamine neurotransmitter synthesis which are typically diagnosed using cerebrospinal fluid examination of monoamine neurotransmitter metabolites. Until now, it has not been systematically studied whether analysis of monamine neurotransmitter metabolites in blood or urine has diagnostic value as compared to cerebrospinal fluid examination, or whether monoamine neurotransmitter metabolites in these peripheral body fluids is useful to monitor treatment efficacy. MethodsAssessment, both by literature review and retrospective analysis of our local university hospital database, of monoamine neurotransmitter metabolites in urine, blood and cerebrospinal fluid, and serum prolactin levels, before and during treatment in patients with AADC and TH deficiency. ResultsIn AADC deficiency, 3-O-methyldopa in serum or dried blood spots was reported in 34 patients and found to be (strongly) increased in all, serotonin in serum was decreased in 7/7 patients. Serum prolactin was increased in 34/37 and normal in 3 untreated patients. In urine, dopamine was normal or increased in 21/24 patients, 5-hydroxyindoleacetic acid was decreased in 9/10 patients, and vanillactic acid was increased in 19/20 patients. No significant changes were seen in monoamine neurotransmitter metabolites after medical treatment, except for an increase of homovanillic acid in urine and cerebrospinal fluid after levodopa therapy, sometimes even in absence of a clinical response. After gene therapy, cerebrospinal fluid homovanillic acid increased in most patients (8/12), but 5-hydroxyindoleacetic acid remained unchanged in 9/12 patients.In TH deficiency, serum prolactin was increased in 12/14 and normal in the remaining untreated patients. Urinary dopamine was decreased in 2/8 patients and normal in 6. Homovanillic acid concentrations in cerebrospinal fluid increased upon levodopa treatment, even in the absence of a clear treatment response. ConclusionsThis study confirms that cerebrospinal fluid is the most informative body fluid to measure monoamine neurotransmitter metabolites when AADC or TH deficiency is suspected, and that routine follow-up of cerebrospinal fluid measurements to estimate treatment response is not needed. 3-O-methyldopa in dried blood spots and vanillactic acid in urine are promising peripheral biomarkers for diagnosis of AADC deficiency. However, in many patients with TH or AADC deficiency dopamine in urine is normal or increased thereby not reflecting the metabolic block. The value of serum prolactin for follow-up of AADC and TH deficiency should be further studied.

Refractory Stage M Ganglioneuroblastoma With Bone Metastases and a Favorable, Chronic Course of Disease: Description of a Patient Cohort.

Refractory stage M neuroblastoma (NB) is associated with a poor prognosis and a progressive course of disease. Here, we describe a unique group of patients with a discrepant clinical course. Seven histologically confirmed ganglioneuroblastoma (GNB) (n=6) and differentiating NB (n=1) patients were identified who were diagnosed with stage M disease based on iodine-123-metaiodobenzylguanidine avid bone metastases. Six patients started on high-risk treatment, without tumor response (stable disease). Treatment was discontinued before the start of consolidation treatment because of refractory response in all patients. Unexpectedly, after cessation of treatment no progression of disease occurred. In 2 patients, the primary tumors expanded (>25%) very slowly during 1.5 and 3 years, and remained stable thereafter. Metabolically, a slow decrease of urinary homovanillic acid and vanillylmandelic acid levels and iodine-123-metaiodobenzylguanidine avidity was observed. All patients are alive with presence of metastatic disease after a median follow-up of 17 years (range: 6.7 to 27 y). Interestingly, at diagnosis, 6 patients were asymptomatic, 6 patients had GNB morphology, and 5 patients had meningeal metastases. These are all features seen in only a small minority of stage M patients. This GNB entity illustrates the clinical heterogeneity of neuroblastic tumors and can be used to further study the developmental origin of different NB subtypes.

Biochemical testing for neuroblastoma using plasma free 3-O-methyldopa, 3-methoxytyramine, and normetanephrine.

Neuroblastoma, the most common extracranial solid tumor of childhood, produces catecholamines that are metabolized within tumor cells. Homovanillic acid (HVA) and vanillylmandelic acid (VMA), the end products of catecholamine metabolism, have limited accuracy for testing of the tumors. This study assessed whether metabolites produced in earlier steps of catecholamine metabolism might offer improved diagnostic accuracy over urinary HVA and VMA. Plasma concentrations of 3-methoxytyramine, normetanephrine, and metanephrine were measured in two pediatric cohorts: (i) 96 children with confirmed neuroblastoma and (ii) 41 children with signs and symptoms of a catecholamine-producing tumor or other neoplasms and in whom neuroblastoma was excluded. Additional measurements of plasma 3-O-methyldopa and relationships of metabolites to MYCN amplification were examined in patient subgroups. Overall, 94 of the 96 patients with neuroblastoma had concentrations of 3-methoxytyramine or normetanephrine above age-specific upper limits of reference intervals, providing a diagnostic sensitivity of 97.9% that was higher (P<0.0001) than that of 82.2% for HVA and VMA. One of the two patients with normal plasma results showed an elevation of plasma 3-O-methyldopa. Diagnostic specificities were, respectively, 95.1% and 84.8%. Areas under receiver-operating characteristic curves confirmed the superior diagnostic power of the plasma than the urinary test (0.994 vs 0.945; P=0.0095). Ratios of plasma 3-methoxytyramine to normetanephrine were 7.2-fold higher (P<0.0001) for patients who had neuroblastomas with MYCN amplification than without MYCN amplification. Measurements of plasma 3-methoxytyramine and normetanephrine provide a highly accurate diagnostic test for neuroblastoma and also offer potential for prognostic risk stratification.

An AND logic gate-based fluorescence probe for the detection of homovanillic acid, an indicator of the tumor

Homovanillic acid (HVA) is one of the major metabolites of catecholamine in human. An elevated level of HVA in urine and blood has been associated with many diseases, including catecholamine-secreting tumors. Consequently, detection of the biomarker HVA in urine is an effective strategy to detect cancer precursors and early stage cancers. In this study, a fluorescence probe is designed and fabricated by integrating lanthanide ions with metal-organic frameworks (MOFs). The fluorescence probe shows distinguished response toward HVA and exhibits ratiometric detection of HVA, rendering it an excellent candidate for sensing devices. Thus, we have designed logic gate operation integrating the probe with logical operations for the intelligent sensing of HVA. Furthermore, this type of luminesce based sensors integrated with logic gate augur for the further application in real-time early diagnosis of tumors in the future. A fluorescence probe was designed and fabricated by integrating lanthanide ions with metal-organic frameworks (MOFs), which showed distinguished response toward HVA, an indicator of tumors in human body.

A Case of Retroperitoneal Primary Neuroblastoma that Developed in Adulthood

Neuroblastoma is a solid malignant tumor found in young children period, but it may also develop in adulthood. Adult neuroblastoma is rare in Japan (incidence of at least 1/100 million). Here, we report on an adult with retroperitoneal primary neuroblastoma. A 32-year-old woman presented with a chief complaint of abdominal tumor diagnosed as neuroblastoma on needle biopsy. The tumor markers for neuroblastoma were 32.6 ng/ml for neuron specific enolase, 30.1 μg/mg Cr for urine vanillylmandelic acid and 42.3 μg/mg Cr for urine homovanillic acid. Imaging showed metastasis to the mediastinal lymph nodes, but bone metastases were not found. The International Neuroblastoma Risk Group Staging System classification for this neuroblastoma was stage M. The tumor involved the left renal artery and aorta. The case was positive for image defined risk factors. Therefore, the patient received three courses of cyclophosphamide, pirarubicin, vincristine, and cisplatin. Tumor shrinkage was noted. We recommended continued chemotherapy, and bone marrow transplantation, but the patient refused further chemotherapy due to the serious side effects of chemotherapy. Tumor extirpation was judged possible by resection of the left renal tumor using a retroperitoneal mirror in combination. The excised tumor was more ganglion-like than at biopsy, and a stroma-rich portion was recognized, which was thought to be maturation due to chemotherapy. MYCN gene amplification was absent. Postoperatively, radiotherapy of the tumor bed and mediastinal lymph nodes was performed and the patient was followed-up. Many adults refuse chemotherapy, which makes sufficient treatment difficult. In adults, even when MYCN gene amplification is not allowed, sufficient observation is necessary since prognosis is the poor.

Polychlorinated biphenyls and depression: cross-sectional and longitudinal investigation of a dopamine-related Neurochemical path in the German HELPcB surveillance program

BackgroundExposure to polychlorinated biphenyls (PCBs) is associated with depressive symptomatology. A cause of depressive symptoms is a disturbance in the neurotransmitter system of dopamine (DA). Animal as well as human studies report that PCBs can influence the DA system. This study examined whether PCB-related depressive symptoms are affected by DA metabolites in humans with high PCB body burden.MethodsThis study is part of the German HELPcB surveillance program (Health Effects in high Level exposure to PCB) for occupationally exposed workers and their relatives. Data was collected from 178 participants on two measurement time points (t1 and t2) with a one-year time lag in between the two time points. PCBs were analyzed in plasma via human biomonitoring and a validated questionnaire was used to identify existence and severity of depressive symptoms. As a surrogate for DA, we measured its metabolites homovanillic acid (HVA) and vanillylmandelic acid (VMA) in urine. Mediation analyses were performed to test whether the association between PCB exposure and severity of depressive symptoms is mediated by urinary concentration of DA metabolites HVA and VMA. The mediation was tested with the SPSS macro MEDIATE.ResultsWe found a significant mediation over time for lower-chlorinated, higher-chlorinated and dioxin-like PCBs. The positive association between PCB exposure with severity of depressive symptoms was mediated by the main DA metabolite HVA. At t1 a higher exposure with PCBs was associated with lower concentration in urinary HVA. A reduced HVA concentration at t1 was correlated with increased depressive symptoms severity at t2. No meditations were found for VMA.ConclusionsThis work indicates that the association of PCB exposure and an increase of depressive symptoms after one year is mediated by the DA metabolite HVA as a surrogate for DA. These are first steps towards finding an explanation for an underlying neurochemical pathomechanism of PCB-related depressive symptomatology.

Simple dilute-and-shoot method for urinary vanillylmandelic acid and homovanillic acid by liquid chromatography tandem mass spectrometry

BackgroundNeuroblastomas are pediatric tumors characterized by overproduction of catecholamines. The catecholamine metabolites, vanillylmandelic acid (VMA) and homovanillic acid (HVA), are used in clinical evaluation of neuroblastoma. Tandem mass spectrometry (LC-MS/MS) is an effective analytical method for measurement of VMA and HVA in urine. MethodsDilute-and-shoot sample preparation was performed in a 96-well format using a liquid handler. Chromatographic separation was achieved using a reverse phase column; detection was accomplished by triple quadrupole mass spectrometry with electrospray ionization in positive mode. Data were acquired by multiple reaction monitoring. Two transitions, quantifier and qualifier, were monitored for each analyte and its stable isotope-labeled internal standard. Analytical specificity studies were performed. ResultsInjection-to-injection time was 4min. The method was validated for linearity, limit of quantification, imprecision, accuracy, and interference. Linearity was 0.5–100mg/l for both analytes. Within-run, between-day, and total imprecision were 1.0–4.1% for VMA and 0.8–3.8% for HVA. The method correlated well with our established HPLC method. Interferences precluding quantitation of VMA in 3% of specimens were reduced significantly (to 0.1% of specimens) using a modified LC gradient to reanalyze affected samples. ConclusionsA simple, robust, economical, fast LC-MS/MS method was developed and validated for measurement of urinary VMA and HVA.

Early detection of tumor relapse/regrowth by consecutive minimal residual disease monitoring in high-risk neuroblastoma patients.

Neuroblastoma is an aggressive pediatric tumor accounting for ~15% of cancer-associated mortalities in children. Despite the current intensive therapy, >50% of high-risk patients experience tumor relapse or regrowth caused by the activation of minimal residual disease (MRD). Although several MRD detection protocols using various reverse transcription-quantitative polymerase chain reaction (RT-qPCR) markers have been reported to evaluate the therapeutic response and disease status of neuroblastoma patients, their clinical significance remains elusive. The present study reports two high-risk neuroblastoma patients, whose MRD was consecutively monitored using 11 RT-qPCR markers (CHRNA3, CRMP1, DBH, DCX, DDC, GABRB3, GAP43, ISL1, KIF1A, PHOX2B and TH) during their course of treatment. The two patients initially responded to the induction therapy and reached MRD-negative status. The patients' MRD subsequently became positive with no elevation of their urinary homovanillic acid, urinary vanillylmandelic acid and serum neuron-specific enolase levels at 13 or 19 weeks prior to the clinical diagnosis of tumor relapse or regrowth. The present cases highlight the possibility of consecutive MRD monitoring using 11 markers to enable an early detection of tumor relapse or regrowth in high-risk neuroblastoma patients.

Reduced Symptoms of Inattention after Dietary Omega-3 Fatty Acid Supplementation in Boys with and without Attention Deficit/Hyperactivity Disorder.

Attention deficit/hyperactivity disorder (ADHD) is one of the most common child psychiatric disorders, and is often treated with stimulant medication. Nonpharmacological treatments include dietary supplementation with omega-3 fatty acids, although their effectiveness remains to be shown conclusively. In this study, we investigated the effects of dietary omega-3 fatty acid supplementation on ADHD symptoms and cognitive control in young boys with and without ADHD. A total of 40 boys with ADHD, aged 8–14 years, and 39 matched, typically developing controls participated in a 16-week double-blind randomized placebo-controlled trial. Participants consumed 10 g of margarine daily, enriched with either 650 mg of eicosapentaenoic acid (EPA)/docosahexaenoic acid (DHA) each or placebo. Baseline and follow-up assessments addressed ADHD symptoms, fMRI of cognitive control, urine homovanillic acid, and cheek cell phospholipid sampling. EPA/DHA supplementation improved parent-rated attention in both children with ADHD and typically developing children. Phospholipid DHA level at follow-up was higher for children receiving EPA/DHA supplements than placebo. There was no effect of EPA/DHA supplementation on cognitive control or on fMRI measures of brain activity. This study shows that dietary supplementation with omega-3 fatty acids reduces symptoms of ADHD, both for individuals with ADHD and typically developing children. This effect does not appear to be mediated by cognitive control systems in the brain, as no effect of supplementation was found here. Nonetheless, this study offers support that omega-3 supplementation may be an effective augmentation for pharmacological treatments of ADHD (NCT01554462: The Effects of EPA/DHA Supplementation on Cognitive Control in Children with ADHD; http://clinicaltrials.gov/show/NCT01554462).

Preliminary study of zonisamide monotherapy in de novo patients with early Parkinson's disease

AbstractBackgroundLittle is known about single administration of zonisamide in Parkinson's disease patients.AimWe aimed to evaluate the therapeutic effects of zonisamide monotherapy in early Parkinson's disease patients.MethodsA total of 10 untreated (de novo) patients with Yahr stage I or II participated. Zonisamide was given at a daily dose of 25 mg for 1 month and increased to 50 mg for the next 2 months. Unified Parkinson's Disease Rating Scale parts I–IV and tremor‐related Unified Parkinson's Disease Rating Scale (items 16, 20 and 21) were examined every month. Serum zonisamide concentrations and urinary homovanillic acid concentrations were measured. Three patients had rapid eye movement sleep behavior disorder. Sleep condition was asked to patients? spouses.ResultsAt 1 month after zonisamide treatment, Unified Parkinson's Disease Rating Scale scores did not differ from the baseline scores statistically. At 2 and 3 months after zonisamide treatment, Unified Parkinson's Disease Rating Scale part III and tremor‐related scores were reduced significantly compared with pretreatment (P &lt; 0.01). Sleep state improved markedly in three patients with rapid eye movement sleep behavior disorder at 1–2 months after zonisamide treatment. The mean serum concentrations of zonisamide (standard deviation) were 2.0 μg/mL (0.9) at 25 mg/day and 6.6 μg/mL (2.3) at 50 mg/day. Urinary homovanillic acid concentrations were not altered before and after zonisamide administration.ConclusionsThe present study showed that zonisamide monotherapy improved motor and sleep dysfunction in de novo patients with early Parkinson's disease. Significant therapeutic benefits were present within 1–2 months. Finally, the data highlight a therapeutic potential of zonisamide monotherapy in tremor‐predominant patients with early Parkinson's disease.

Urinary homovanillic and vanillylmandelic acid in the diagnosis of neuroblastoma: Report from the Italian Cooperative Group for Neuroblastoma

BackgroundUrinary homovanillic and vanillylmandelic acid (HVA and VMA) are well known biomarkers for the management of neuroblastoma (NB). Very few and contradictory publications on their diagnostic performance are present in the literature. The aim of this study is to review the results of HVA/Cr and VMA/Cr obtained by the reference laboratory of the Italian Cooperative Group for NB within a 7-year period using HPLC-EC. ProcedureUpdated reference intervals based on age as a continuous variable were calculated by using a multivariate statistical analysis. The diagnostic performance of the two biomarkers has been established by calculating their specificity and sensitivity and by receiver operating characteristics (ROC) curves for different ages and stages of disease. ResultsAccurate age-related reference intervals were obtained from 648 HVA/Cr and 671 VMA/Cr results derived from patients in which the diagnosis of neuroendocrine tumors was excluded. Sensitivity, specificity and ROC curves were obtained from 169 HVA/Cr and 179 VMA/Cr results from confirmed NB patients. The best diagnostic performance was obtained in stage 4S tumors and in children <18months. ConclusionsThis is the first report, to our knowledge, that analyzes in depth the diagnostic performance of HVA/Cr and VMA/Cr for NB in different stages and age subgroups. In addition, the present work provides cut-off points able to discriminate between NB patients and negative subjects suspected to have NB and could be of help in taking medical decisions.

Determination of four biogenic amine metabolites in urine by high-performance liquid chromatography

To establish a method for simultaneously determining vanilmandelic acid (VMA), 5-hydroxyindoleacetic (5-HIAA), 3, 4-dihydroxyphenylacetic acid (DOPAC), and homovanillic acid (HVA) in urine by high-performance liquid chromatography (HPLC). After being filtered with a 0.45 µm membrane syringe filter, the urinary samples were injected directly into the HPLC system using a C18 chromatographic column and a fluorescence detector. The excitation and emission wavelengths were chose as 280 nm and 315 nm, respectively, and the urinary samples were carried with a mobile phase of methanol-0.1 mol/L phosphate buffered solution (V/V = 20:80) at a flow rate of 1.0 ml/min and an injection volume of 20 µl. Using the method reported here, the correlation coefficients of VMA, 5-HIAA, DOPAC, and HVA were 0.9999, 0.9998, 0.9997, 0.9999, respectively, over linear ranges of 0-2.5, 0-2.0, 0-2.0, and 0-2.5 µg/ml, the minimum detectable concentrations were 0.006, 0.008, 0.012, and 0.0082 µg/ml, the average precisions were 4.2%, 3.7%, 4.9%, and 3.6%, and the recovery rates were 91%∼102%, 93%∼101%, 94%∼101%, and 89%∼ 102%. This determination method is simple, efficient, accurate, and sensitive for the simultaneous detection of VMA, 5-HIAA, DOPAC, and HVA in urine.

Opsoclonus Associated With Salmonellosis in a 6-Week-Old Infant

A 6-week-old male infant presented with 2 days of fever, emesis, and diarrhea, associated with episodic and chaotic rapid eye movements, determined to be opsoclonus. An electroencephalogram (EEG) obtained during the events was normal. He was treated empirically for meningitis, and an initial workup for neuroblastoma including urine homovanillic acid and vanillylmandelic acid levels, abdominal ultrasonography, and computed tomography (CT) of the chest, abdomen, and pelvis was negative. Stool and blood cultures were positive for Salmonella, and antibiotic regimen was adjusted appropriately. Over the next few days, his fever, emesis, and diarrhea subsided, and the opsoclonus resolved by hospital day 6. He was back to baseline by hospital day 9. Although there have been cases of parainfectious opsoclonus associated with Lyme disease, enterovirus, Streptococcus, and West Nile virus, this represents the first reported pediatric case of opsoclonus associated with salmonellosis. Only 2 such cases in adults have been reported in the literature.

Catecholamines influence myocardial 123I MIBG uptake in neuroblastoma patients

Cardiac 123I metaiodobenzylguanidine (MIBG) imaging can be influenced by several factors. We evaluated the relationship between catecholamine measurements and cardiac 123I MIBG uptake in neuroblastoma patients. 30 neuroblastoma patients were retrospectively assessed on cardiac 123I MIBG uptake and urinary catecholamine dopamine and metabolites, homovanillic acid (HVA) and vanillylmandelic acid (VMA). Cardiac 123I MIBG uptake was quantified by heart-to-mediastinum (H/M) ratios, which were calculated into standard deviation scores (SDS) using age-specific reference values. In 17 (57%) and 12 patients (40%) H/M ratio measurements were below -1.0 and -2.0 SDS at diagnosis. A significant inverse correlation between the average of urine metabolites HVA and VMA, and H/M ratio SDS was observed (r -.39, p = 0.04). Furthermore, there was a significant correlation between the urinary catecholamine metabolite HVA and H/M ratio SDS (r -.40, p=0.04). Routine calculation of H/M ratios in 123I MIBG scintigrams of neuroblastoma patients is not helpful because it will not identify cardiac ventricular dysfunction in this patient category. A low H/M ratio on 123I MIBG scintigraphy is explained by increased cathecholamine levels secreted by neuroblastoma tumours.