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PubMedDate not supplied

[Mercapturates and biologic monitoring: styrene].

The biological monitoring of styrene exposure is currently performed by the measurement of the urinary excretion of mandelic acid (MA) and phenylglyoxylic acid (PGA), which originate from the conversion of styrene 7,8-epoxide (SO), an electrophilic compound considered responsible for most toxic effects of styrene. In rats, an alternative pathway in the detoxification processes of SO has been shown, which involves its conjugation with glutathione (GSH), leading to the excretion of N-acetyl-S-(1-phenyl-2-hydroxyethyl)-cysteine (M1) and N-acetyl-S-(2-phenyl-2-hydroxyethyl)-cysteine (M2). Giving the chiral nature of SO, which is present in two enantiomeric forms (R and S), both M1 and M2 consist of two diastereoisomers: thus, four specific mercapturic acids are excreted in styrene-exposed rats, namely M1-R, M1-S, M2-R and M2-S. Until now, the excretion of these compounds in man has not been confirmed directly, giving the analytical difficulties in measuring the low levels of urinary mercapturic acids which are expected following styrene exposure in the working environment. In the present study we applied an analytical method, based on HPLC with fluorometric detection, to measure the excretion of M1-R, M1-S, and M2 in post-shift urines from 22 workers exposed to styrene and in 10 unexposed subjects. The results clearly demonstrated that the GSH pathway is involved in the detoxification processes of styrene, even if to a low extent (the biotransformation rates of styrene to mercapturic acids varied from 0.021 to 0.325%) and that M1 and M2 are specific for styrene exposure, in fact unexposed subjects showed no detectable amounts of these metabolites. In spite of the marked interindividual variability, significative correlations were found between mercapturic acids excretion and environmental styrene concentration or urinary levels of MA and PGA. The urinary levels of M1-S and M1-R were significantly different, thus indicating a stereoselectivity of the enzymes involved in the biotransformation of styrene to mercapturic acids.

Acetylcysteine↗
PubMedDate not supplied

[Evaluation of the usefulness for neonatal mass screening in light of 35 years personal experience].

The results and the significance of neonatal mass-screening programmes for inborn errors of metabolism, conducted by the National Research Institute of Mother and Child (NRIMC), are discussed. As the first in Poland, in 1964, mass-screening for phenylketonuria (PKU) was introduced. The BIA-Guthrie test was used. Other Guthrie tests (GBIA) were applied in homocystinuria, tyrosinemia, histidinemia and leucinosis (Maple Syrup Urine Disease-MSUD). In the middle of the 60. the Beutler and Baluda test was introduced for galactosaemia, as well as the Efron urine test in infant screening for different inborn errors of metabolism. In the middle of the 70., neonatal mass-screening for cystic fibrosis (CF, mucoviscidosis) was started. Meconium tests and the sweat test with ion selective chloride electrode were used. Apart from inborn errors of metabolism, we also introduced a screening programme for neuroblastoma in which vaniline mandelic acid (VMA) in urine was estimated and for congenital hypothyroidism were TSH level was assessed. The results of screening are shown in the tables and in the figures. In our opinion the best clinical results are obtained with screening for congenital hypothyroidism and for PKU, since very early detection and treatment in these diseases prevents severe mental retardation. We therefore consider that both these screening programmes should be treated as obligatory examinations in all neonates. Taking into consideration the fact that there are different types of hyperhenylalaninemias, the principles of differential diagnosis are discussed. Molecular genetic investigations, carried out in the NRIMC Department of Genetics proved to be a very important procedure in the verification of diagnosis of different mutations. The authors also discuss the problem of dietary treatment duration in PKU. In our opinion the hypophenyloalanine diet regimen in girls, should not be discontinued during adolescence, since there is the problem of maternal PKU and the possibility of foetal damage. The results of our own investigations of maternal PKU are discussed. The significance of mass-screening for galactosemia is still under discussion. In our opinion, mass-screening for galactosemia is not useful and we have discontinued it. Selective screening has been started combined with molecular genetic studies in high risk families. In the future, we plan to prepare guidelines on the principles of diagnosis and treatment of galactosemia in children and women in the reproductive age. Mass-screening for cystic fibrosis is also still under discussion. The results of the early screening programmes were not satisfactory and the tests were discontinued. In 1998, after reorganisation of the whole system, CF screening, using tripsin-radioimmune assays, was started again. The new screening programme is combined with molecular genetic investigation of different mutations. It is still too early to assess the importance and success of this CF mass-screening programme. We decided to discontinue the screening for homocystinuria, histidinemia, tyrosinemia, leucinosis and for neuroblastoma, since these programmes did not comply with criteria of mass-screening. In 1997, major reorganisation of screening programmes for inborn errors of metabolism, at NRIMC, was undertaken. The Guthrie test for PKU was changed to a quantitative colorimetric method. The immuno-luminometric method is used for TSH estimation. The whole system is based on complete computer control of all the steps of screening, from blood sampling on filter paper until the final diagnosis. The advantages of this modern system of organisation of the screening programme are discussed.

Decision Trees↗
PubMedDate not supplied

Abdominal and pelvic extra-adrenal paraganglioma: a review of literature and a report on 7 cases.

INTRODUCTION: Extra-adrenal paraganglioma (pheochromocytoma) is a rare tumor. Herein we describe the clinical and pathological findings in patients with paragangliomas of the urinary bladder, seminal vesicle and retroperitoneum. METHODS: Between January 1994 and January 2001, extra-adrenal paragangliomas were diagnosed in 7 patients: 3 males and 4 females. The mean age of our patients was 32 +/- 15.9 years. We reviewed the clinical data. Urinary metanephrines and vanillyl mandelic acid and blood catecholamine levels were estimated in 4 cases. CT scan and/or MRI were used in the imaging of all cases. 123I-MIBG was used in only 1 patient, who harbored multiple tumors. All the patients but one underwent surgical treatment. RESULTS: The definitive diagnosis was made by histopathological examination of the removed tumors and was confirmed in all cases by the immunohistochemical stains of chromogranin A and S100 protein. There was metastasis in the pelvic lymph nodes in 1 patient. Follow-up ranged from 3 to 82 months (mean = 37.9 +/- 25.8). The catecholamine level was elevated in 3 patients under basal conditions and during endoscopic resection of the tumor in a fourth patient. In all cases, the catecholamine level was normalized after surgery. There was no recurrence or metastasis in any case following surgery. CONCLUSION: Pre-operative diagnosis of nonfunctioning bladder paraganglioma is difficult, but the tumors should be suspected in patients who have hypertension, hematuria or mass effects due to the tumor growth in the pelvis and/or retroperitoneum. Six of the seven cases reported here were found in the usual locations: 3 in the urinary bladder, 2 in the renal hilum and 1 in the organ of Zuckerkandl. One patient had multiple tumors, including a paraganglioma of the seminal vesicles. Resection is the treatment of choice, and in the case of urinary bladder paraganglioma should include total cystectomy. In patients with unresectable multiple tumors, medical therapy may be used to control hypertension.

Abdominal Neoplasms↗
PubMedDate not supplied

[On a case of Guillain - Barre's polyradiculoneuritis with arterial hypertension (author's transl)].

A twenty year old man affected by Guillain-Barré's radiculopolyneuritis with tetraparesis had high protein and only few cells in the C.S.F., with no cranial nerve involvement or respiratory difficulty. He had high arterial pressure (both diastolic and systolic) for about three months accompanied by episodes of tachycardia and hyperhydrosis. Investigations of renal functionas well as catecholamine and vanil-mandelic acid urinary excretion were normal. Tilting test and carotid sinus reflex were normal. The patient recovered almost completely eight months after the onset of his illness. The presence of arterial hypertension in the Guillain-Barré's syndrome has been rarely reported with no respiratory involvement; however this condition may be less rare than suspected. The pathogenesis of this complication is not easy to explain. According to the authors this condition may be due, in cases, to impairment of the sympathetic system mostly at peripheral level. In some cases of Guillain-Barré's syndrome renal involvement of immunopathological origin might be the cause of hypertension. The authors emphasize the importance of a correct evaluation of symptoms in the prognosis and in the choice of therapy.

Adult↗
PubMed1975

The effects of heroin on catecholamine metabolism in man.

In a study of the effects of heroin administration in nine human subjects, urinary catecholamines and metabolites were examined during an initial drug-free baseline period, a ten-day period of heroin administration and a subsequent period of methadone detoxification. All catecholamines and metabolites tended to be increased over baseline values on the first day of heroin administration. However, markedly different patterns of change emerged on subsequent days of heroin administration. Norepinephrine and normetanephrine remained increased throughout heroin administration. Epinephrine was increased during the early phase of heroin administration but returned to baseline values during the latter phase of heroin administration. After the increase on the first day of heroin administration, metanephrine decreased and substantial decrements below baseline values occurred during the latter phase of heroin administration. After increasing on the first day of heroin administration, 3-methoxy-4-hydroxy-mandelic acid (VMA) returned to approximately baseline values. During heroin administration, an increase in 3-methoxy-4-hydroxyphenylglycol (MHPG) excretion was observed in a subgroup of four of the nine subjects studied. This is in contrast to the increase in normetanephrine excretion and the decrease in metanephrine excretion that was observed in the entire group of nine subjects. It is conceivable that persistance of, or development of, tolerance might account for the failure to observe an increase in MHPG excretion in all of the subjects. It appeared as if the increase in MHPG excretion began on the day prior to the administration of heroin in the subgroup of patients with increased MHPG excretion during heroin administration, suggesting the possibility of an anticipatory or conditioned response, with the anticipation of heroin producing an increase in MHPG excretion.

Catecholamines↗
PubMed1975

[Chromaffine tumours: diagnosis and catamnestic features based on the data collected at the Institute of Experimental Therapy between 1949 and 1974 (author's transl)].

From 1949 to 1974, urine samples of 1669 patients with unclarified arterial hypertension were tested for non-conjugated catecholamines. Chromaffine tumours--among them one pheochromoblastoma and two families with inherited forms--were found in 1.1% of all cases. With the procedure applied, adrenergic alpha- and/or beta-mimetic actions on the circulation of cats can be identified when the excretion of total catecholamines is increased by the factor 1.5 to 2.0. Hence, chromaffine tumours with smaller excretion rates (about 200 mug/24 h) are also detectable, so in one case where the excretion of vanillyl-mandelic acid was normal. Thus all prerequisites concerning sensitivity and specificity of a screening method are fulfilled. The large variety of symptoms of chromaffine tumours becomes obvious from the catamnestic data of 19 patients indicating problems which may arise in differential diagnosis.

Adolescent↗
PubMed2002

[Personal experience in diagnosis and localization of pheochromocytoma].

INTRODUCTION: Pheochromocytomas are most commonly tumours of adrenal medullary origin. Pheochromocytoma by definition produces and secretes catecholamines. Similar tumours that do not secrete active substances of any kind are called non functioning paragangliomas. The hallmark clinical manifestation of pheochromocytoma is hypertension accompanied with various signs and symptoms in excess of catecholamines or other bioactive substances. The early diagnosis of pheochromocytoma is important not only because it offers the possibility of curing hypertension but also because unrecognised pheochromocytoma is a potentially lethal condition. The aim of this article is to stress the specify of the clinical finding, diagnostical values of the laboratory tests and possibilities of morphological localizing techniques in a series of 98 patients with surgically proven pheochromocytoma. RESULTS: Over the period from 1954 to 2002 pheochromocytoma was diagnosed and surgically treated in 98 patients. The diagnosis was confirmed at operation except in patients who refused operation or continued the examination in other Clinical wards. There were 59 females and 48 males (F:M = 1.23:1), the age ranged from 7 to 64 years with the pick incidence in the second and third decades of life in males and the third and fourth decades of life in females. The basic clinical characteristic was hypertension which was found in 94% of patients with an approximately equal frequency of fixed and paroxysmal hypertension cases. The most often accompanning manifestations were headache (62%), perspiration (61%) and palpitations (65%). A high level of vanyl mandelic acid (VMA) and free catecholamines in 24-hour urine collection confirmed the diagnosis in 94% of cases. In boderline cases we performed dynamic tests, the most relevant among them being the test with phentolamin. It was positive in 95% of patients. Retropneumothomography contributed to a successful localisation of tumour in 83% of cases. Computed tomography (CT) was performed in 69 patients and was positive in 97% of them. Magnetic resonance imaging (MRI) localized the tumour in all 16 patient in whom it was performed. The whole body MIBG-J-131 (metaiodobenzylguanidine) scanes were positive in 92% (45/49) and false negative in the remainder of 8% (4/49) of cases. Selective angiography was performed in 40 patients and in all it was positive. DISCUSSION: Although pheochromocytomas were among the first recognized adrenal tumours, the prompt and safe diagnosis is mandatory up to date. The average annual incidence has been estimated by several epidemiologic studies to range from 0.8 to between 1.55 and 2.1 million persons per year. It is reported that it is curable cause of hypertension in 0.1% to 1% of cases. Pheochromocytoma has been classified as a "10% tumour" because various studies have shown that each of the characteristics mentioned bellow occurs with a frequency of approximately 10%: bilateral, extra-adrenal, multiple, malignant, familial and occurring in children. Our series of patients has a similar distribution: pheochromocytoma was in 9.2% of patients extra-adrenal, in 7.1% bilateral, in 9.2% multiple and in 4.08% malignant. Hypertension was the constant finding in 94% of our patients. Three clinical patterns of hypertenson have been observed. The first is paroxysmal hypertension, and the others are fixed or combinations of fixed and paroxysmal hypertension. According to our experience there were the equal incidence of all forms of hypertension. We noticed, like others, when the triad of headache, sweating and palpitations is accompanied by hypertension, the diagnosis of pheochromocytoma can be made with specify and sensitivity over 93%. In absence of this finding the diagnosis can be excluded with certainty of 99%. As a specify of the clinical finding, we mention two patients with manifestations of hypercorticism, two patients with pheochromocytoma of the urinary bladder, and four with MEN syndrome (one with MEN 2A and three with MEN 2B). For confirming the diagnosis the most relevant laboratory test was the higher level of VMA and free catecholamines in 24-hour urine collections. Once pheochromocytoma has been diagnosed by biochemical analyses, the anatomic location of the tumour or tumors must be determined. Currently, the best approach is to obtain MIBG-J-131 scan and then to perform MRI or CT of the abdomen and other areas identified on MIBG scan in order to provide more accurate spatial information. With this approach the great majority of pheochromocytomas can be localized. CONCLUSION: There is no classic picture, no stereotype for pheochromocytoma, although the history and physical finding are helpful. Patients come to the clinician in a variety of ways and settings. They may have classic attacks of hypertension accompanied with headache, perspiration and paplpitations or they may have identical symptoms and physical findings as the patients with primary hypertension. On the other hand, they may have signs and symptoms of diabetes mellitus, hyperthyroidism, hypercalcaemia, congestive heart failure, myocardial infarction, malignant hypertension or a variety of other conditions. Rarely, they have no complaints at all. Once the diagnosis was made, spatial localizing of the tumour or tumours, and surgical treatment are necessary. Unrecognized disease may be fatal.

Adolescent↗
PubMed2003

Ganglioneuroma presenting as an asymptomatic huge posterior mediastinal and retroperitoneal tumor.

Ganglioneuroma is a rare, differentiated, benign and slow-growing tumor that commonly arises from sympathetic ganglion cells. Most of them are asymptomatic and found incidentally. We here report a quite rare case of silent huge ganglioneuroma growing in both posterior mediastinum and retroperitoneum occurring in a 3.5-year-old girl. The patient was relatively well before and incidentally found to have a huge chest mass by chest X-ray film at an episode of respiratory tract infection. Computed tomography showed a huge tumor extending from bilateral posterior mediastinum to the level of the adrenal gland in the retroperitoneum. Initially, neuroblastoma was highly suspected and 24-hour urine vanillyl mandelic acid was slightly elevated. Cytology by bone marrow aspiration revealed no tumor nests or clumps. Biopsy and pathology proved it as ganglioneuroma (GN). Due to too extensive involvement of the tumor and compression of the vital vessels, surgical removal became difficult. The family of the patient refused surgery due to there being no significant symptoms. Because of the potential for growth of unresectable GN and because the component of neuroblasts could not be completely excluded, the patient was still in dangerous status. The only thing we can do is to keep the family alert and continue regular follow-up.

Child, Preschool↗
PubMed1992

[A case of acute idiopathic pandysautonomia--a histochemical study of sural nerve by acetylcholinesterase staining].

A 30-year-old man had an acute onset of orthostatic lightheadedness, sweating disturbance, paroxysmal cough and loss of potency. These symptoms reached the peak in two weeks, and then remitted very slowly. He was admitted to our hospital for further evaluation when he was 39 years old. Neurological examinations revealed right Horner's syndrome, dry skin and impotence, but neither motor nor sensory system was impaired. No abnormalities were found on routine examinations of the blood and cerebrospinal fluid, motor and sensory nerve velocities, computed tomography and electroencephalography. On sural nerve biopsy, the density of unmyelinated fibers was mildly decreased (13,857/mm2), whereas that of myelinated fibers was normal (7,220/mm2). Autonomic function tests disclosed orthostatic hypotension (-31 mmHg) on tilting, reduced levels of serum noradrenaline and vanillyl mandelic acid, supersensitive responses to noradrenaline infusion and adrenaline eye-dripping, severe sweating impairment and complete absence of sympathetic skin response. On the other hand, Aschner's test, Czermak's test and coefficient variation of R-R intervals were all normal. These results suggested that the chief lesion was located in the postganglionic fiber of sympathetic efferent pathway. We (Hayashi et al, 1990) quantified acetylcholinesterase (AchE)-positive fibers in the specimens of sural nerve biopsy, and reported that the density of AchE-positive fibers was correlated to the function of sympathetic postganglionic fibers. The density of AchE-positive fibers in the present case of acute idiopathic pandysautonomia (AIPD) was severely decreased to 225/mm2 by optical microscopy (control: 5,703 +/- 1,289/mm2), and to 2,996/mm2 by electron microscopy (control: 14,112 +/- 3,987/mm2).(ABSTRACT TRUNCATED AT 250 WORDS)

Acetylcholinesterase↗
PubMedDate not supplied

A monoblock resection for malignant phaeochromocytoma.

BACKGROUND: Phaeochromocytoma is a rare surgically treatable cause of hypertension. The aim of this paper is to present a case of phaeochromocytoma treated in Port Harcourt. METHOD: The case record of a patent with phaeochromocytoma and a review of the relevant literature. RESULT: A 40 year-old man presented with episodic malignant hypertension resistant to several anti-hypertensive drugs. A 24-hour urinary Vanillyl Mandelic Acid estimation was high at 68 mmol. An ultrasound scan revealed a huge right suprarenal mass. Preoperative medication was given to reduce the blood pressure and prevent perioperative arrhythmias. Under general anaesthesia with propofol, the tumour was explored. It appeared to invade the kidney and there were multiple hepatic secondaries. It was resected in block with the kidney. Intra- and postoperatively he had episodes of hypertension which were successfully controlled with a combination of intravenous chlorpromazine 50 mg, tramadol 100 mg and lorazepam 4 mg. Histopathology examination showed that the suprarenal mass and hepatic lesions were identical showing malignant phaeochromocytoma. The post-operative period was satisfactory. Cytotoxic drugs were not given because they were not available. On review 8 weeks later, the patient remained well. CONCLUSION: Meticulous anaesthetic and surgical skills are essential in the resection of a phaeochromocytoma.

Adrenal Gland Neoplasms↗
PubMed2004

[Adrenocorticotropic hormone-secreting adrenal pheochromocytoma: a case report].

A 55-year-old woman with transient faintness was referred to our hospital. Laboratory studies showed high levels of plasma catecholamines, cortisol, adrenocorticotropic hormone (ACTH) and urinary vanyl mandelic acid (VMA). Abdominal computed tomography (CT) showed a right adrenal tumor measuring 4.5 cm diameter that was enhanced heterogeneously by contrast medium. Brain CT and chest CT did not detect any other tumors. Under the clinical diagnosis of ectopic ACTH secreting adrenal pheochromocytoma, we performed right adrenalectomy. Pathological findings showed pheochromocytoma, and tumor cells were heterogeneously stained by anti-ACTH antibody.

Adrenal Gland Neoplasms↗
PubMed2003

[Pheochromocytoma in Dakar: report of nine cases].

Pheochromocytoma is a catecholamine-secreting neoplasm of chromaffin tissue. The most common symptom is hypertension but there are incidentally discovered forms at imaging. From 1981 to 1998, the authors observed nine pheochromocytomas through three hospitals in Dakar. This study included seven male and two female patients. The average age was 31.61 years. Hypertension was present in 77% of the cases. Headache, palpitations and sweating were the authors most frequent symptoms, occuring in 55% of cases. Measurement of vanillyl mandelic acid level in six cases and urinary metanephrines in three cases made the diagnosis. There were six adrenal and three extra adrenal pheochromocytomas with two malignant tumors features. In our countries, measurement of urinary metanephrines and computed tomography processing may improve detection of pheochromocytomas.

Adrenal Gland Neoplasms↗
PubMed1992

[Adrenal gland pheochromocytomas. Apropos of 35 operated patients].

Thirty-five patients (20 female and 15 male, mean age = 47 years) operated on for an adrenal pheochromocytoma were reviewed. Catecholamine excessive production was symptomatic in 33 patients (94%). Urinary excretion of vanyl-mandelic acid, catecholamines and metanephrine was abnormal in 84%, 75% and 90% of cases, respectively. Tumor was presumed benign (no metastasis) in 31 cases. Sensitivity of CT scan (n = 35) and magnetic resonance imaging (n = 13) was 100%. Meta-iodo-benzylguanidine scan (n = 19) always recognized the main tumor, but did not visualize 1 second tumor in 1 patient and 1 metastasis in 1 other patient. An anterior intraperitoneal approach was performed in all cases. Operative mortality rate was 5.7%. In the last 15 patients, systematic preoperative treatment by prazosine did not lead to fall in rates of peroperative arrythmia and hemodynamic disorders. Twenty-two of 25 (88%) hypertensive patients remained normotensive without medication postoperatively. The risk of undiagnosed pheochromocytoma and problems in resection of large right-sided tumors are discussed.

Adolescent↗
PubMedDate not supplied

Effects of repeated intermittent exposures to nitrous oxide on central neurotransmitters and hepatic methionine synthetase activity in CD-1 mice.

The central neurotransmitters and hepatic methionine synthetase (MS) appear to play an important role in mediating the side effects associated with N2O exposure. Male CD-1 mice were exposed to 0, 50, 500, and 5,000 ppm of N2O 6 hr per day, 5 days a week for 2 or 13 weeks. One day after the last day of exposure, the animals were decapitated and steady state concentrations of norepinephrine (NE), dopamine (DA), serotonin (5-HT), 3-methoxy-4-hydroxy-mandelic acid (VMA), 3-methoxy-4-hydroxyphenyl glycol (MOPEG), dihydroxphenylacetic acid (DOPAC), and 5-hydroxyindoleacetic acid (5-HIAA) were determined in six discreet brain regions using electrochemical high-performance liquid chromatography. Hepatic MS activity was measured using a newly developed non-isotopic method. After a 2-week exposure to 5,000 ppm N2O, levels of NE and DA in some brain regions were significantly increased and were accompanied by significant decreases in the levels of their major metabolites. Serotonin levels were significantly decreased in certain brain regions. After the 13-week exposure to 5,000 ppm N2O, levels of NE, DA, and 5-HT significantly increased in the hypothalamus. Hepatic MS activity was not affected at any dose level of N2O used. The alterations in neurotransmitter levels may be related to the reported clinical and behavioral effects associated with N2O misuse or occupational exposures.

5-Methyltetrahydrofolate-Homocysteine S-Methyltran↗
PubMed2006

[Effects of styrene on the dopaminergic transmitter content and monoamine oxidase activity in different sections of rat brain].

OBJECTIVE: To observe the effect on dopaminergic transmitter content and of monoamine oxidase (MAO) activity at dose of experiment in different sections of rat brain exposed bu acutely and subacutely styrene. METHODS: Rats were administrated orally with styrene of at dose of 600mg/kg for acute, 150, 300 and 600mg/kg for subacute experiment; recovery group were observed after 3 weeks exposure of styrene and intervened group were injected intraperitoneally at dose of 600mg/kg Levodopa (L-dopa) ; the urinary metabolites of styrene mandelic acid (MA) and phenylglyoxylic acid (PGA) were monitered as inner dosage, and the content of dopamine (DA) and activity of MAO were evaluated. RESULTS: The result indicated that the content of urinary MA and PGA were associated with dosage positively, and MA may be more sensitive as inner dosage of styrene exposure since the background of PGA. Levels of DA in retina, hypophysis and striatum were decreased after styrene exposure, the activities of MAO in hypophysis were increased and were reduced in retina and striatum. CONCLUSION: It was suggested dopaminergic system could be participated in styrene neurotoxicity.

Animals↗
PubMed1991

[Screening for neuroblastoma in infants aged 6 months. A method of testing].

In a number of cases, neuroblastoma (NB) may be diagnosed by routine screening of the urine for vanillinic-mandelic acid (VMA) and homovanillinic acid (HVA) in symptomfree infants at the age of six months. Early diagnosis of this disease may possibly improve the prognosis. The object of this project was to establish a method of measuring VMA and HVA concentrations in urine collected on filter paper and to assess participation by the parents as regards three different methods of collecting urine with the object of establishing a population screening programme for NB in Denmark. A total of 1,111 infants aged 6-8 months participated in the investigation. The equipment for testing the urine was given in three different was: 1) By the health nurses (County of Arhus), 2) By the general practitioner at the 6-month vaccination (County of Ringkøbing) and 3) By post (County of Viborg). In Arhus, the health nurses delivered the equipment to 96.7% of the age group concerned. Altogether, urine samples were obtained from 673 infants (61%). Participation was greatest in the County of Arhus (66%) and the County of Ringkøbing (62%) and lowest in the County of Viborg (54%). Two infants were found with marginally raised VMA or HVA but these values were found to be normal on repeated examinations. No cases of neuroblastoma were found in the material nor in the screened group in the course of 1 1/2 years after the conclusion of the investigation. In just over 3% of the cases, renewed urine samples had to be sent on account of too little urine on the filter paper. If current population investigations reveal that screening for neuroblastoma can alter the course of the disease in children, the method described here may form the basis for introduction of population investigations in Denmark.

Denmark↗