Positive Biochemical Tests Research Articles

Diagnostic performance of magnetic resonance imaging features to differentiate adrenal pheochromocytoma from adrenal tumors with positive biochemical testing results

BackgroundIt is extremely essential to accurately differentiate pheochromocytoma from Adrenal incidentalomas (AIs) before operation, especially biochemical tests were inconclusive. We aimed to evaluate the value of magnetic resonance imaging (MRI) features to differentiate pheochromocytomas among adrenal tumors, among which the consequences of biochemical screening tests of catecholamines and/or catecholamine metabolites are positive.MethodsWith institutional review board approval, this study retrospectively compared 35 pheochromocytoma (PHEO) patients with 27 non-pheochromocytoma(non-PHEO) patients between January 2022 to September 2023, among which the consequences of biochemical screening tests of catecholamines and/or catecholamine metabolites are positive. T test was used for the independent continuous data and the chi-square test was used for categorical variables. Univariate and multivariate logistic regression were applied to find the independent variate of the features to differentiate PHEO from non-PHEO and ROC analysis was applied to evaluate the diagnostic value of the independent variate.ResultsWe found that the T2-weighted (T2W) signal intensity in patients with pheochromocytoma was higher than other adrenal tumors, with greatly significant (p < 0.001). T2W signal intensity ratio (T2W nodule-to-muscle SI ratio) was an independent risk factor for the differential diagnosis of adrenal PHEOs from non-PHEOs. This feature alone had 91.4% sensitivity and 81.5% specificity to rule out pheochromocytoma based on optimal threshold, with an area under the receiver operating characteristics curve (AUC‑ROC) of 0.910(95% C I: 0.833–0.987).ConclusionOur study confirms that T2W signal intensity ratio can differentiate PHEO from non-PHEO, among which the consequences of biochemical screening tests of catecholamines and/or catecholamine metabolites are positive.

FRI260 Adrenal Hemangioma, Mimicker Or Malignant?

Abstract Disclosure: C. Pham: None. C.E. Chiu: None. B. Barnett: None. Background: Adrenal hemangioma is a rare condition that can mimic other adrenal pathologies. Clinical Case: A 49 year old male with history of heart failure presented with cardiogenic shock requiring inotropes and heart transplant evaluation. On CT patient was noted to have a 2.2 cm left adrenal nodule containing calcifications. Initial tests had indeterminate 1 mg overnight DST, normal plasma free metanephrines and elevated plasma free normetanephrines 2.06 nmol/L (0-0.89 nmol/L). PRA was 22.82 ng/mL/hr (0.25-5.82 ng/ml/hr) with aldosterone 10.8 ng/dL (&amp;lt;16 ng/dL) on spironolactone. 24 hour urine tests showed normal free cortisol 9.8 mcg/24hr (4-50 mcg/24hr) and elevated total metanephrines at 1245 mcg/24hr (182-739 mcg/24hr), metanephrines at 303 mcg/24hr (58-283 mcg/24hr), and normetanephrines at 942 mcg/24hr (88-649 mcg/24hr). Adrenal CT demonstrated HU of 59 units on noncontrast phase, with -86.7% absolute washout and -17.6% relative washout. I-123 MIBG Scan was obtained with no radiotracer uptake noted. Patient underwent laparoscopic adrenalectomy for definitive diagnosis and was found to have adrenal hemangioma with CD31 and ERG with hemosiderin laden macrophages on pathology. Adrenal hemangioma is rare and can mimic other adrenal pathology. Most patients present with abdominal symptoms such as flank pain or are found to have an adrenal incidentaloma on imaging. CT findings are associated with heterogenous internal structure, peripheral patchy enhancement, or calcifications, which are also seen in malignancy and pheochromocytoma. In all cases, HU if recorded are noted to be &amp;gt;10 on the unenhanced phase and &amp;lt;60% absolute washout. In one case series of 52 adrenal hemangiomas, only 3 patients had positive biochemical tests and on average were 11 cm in size. Formal diagnosis is made pathologically. Treatment for adrenal hemangioma is typically resection for symptomatic relief, with some patients with small lesions electing to observe. In all surgical cases reviewed in a case series adrenalectomy was pursued as opposed to needle biopsy due to large size of lesion and concern for possible malignancy. In this specific case, biochemical testing was falsely positive given the patient’s presentation of cardiogenic shock and inotropes causing elevated catecholamine levels and given imaging findings could not fully rule out pheochromocytoma. Given the small size of lesion, the patient in a non-transplant setting likely could have pursued close observation as opposed to resection. Conclusion: Adrenal hemangioma can have imaging characteristics that can mimic several other adrenal pathological conditions, such as malignancy or pheochromocytoma. Treatment through surgical management is likely not necessary in patients with hemangioma, though would be important in ruling out other adrenal pathology. Presentation: Friday, June 16, 2023

Prediction of metastatic pheochromocytoma and paraganglioma: a machine learning modelling study using data from a cross-sectional cohort

Pheochromocytomas and paragangliomas have up to a 20% rate of metastatic disease that cannot be reliably predicted. This study prospectively assessed whether the dopamine metabolite, methoxytyramine, might predict metastatic disease, whether predictions might be improved using machine learning models that incorporate other features, and how machine learning-based predictions compare with predictions made by specialists in the field. In this machine learning modelling study, we used cross-sectional cohort data from the PMT trial, based in Germany, Poland, and the Netherlands, to prospectively examine the utility of methoxytyramine to predict metastatic disease in 267 patients with pheochromocytoma or paraganglioma and positive biochemical test results at initial screening. Another retrospective dataset of 493 patients with these tumors enrolled under clinical protocols at National Institutes of Health (00-CH-0093) and the Netherlands (PRESCRIPT trial) was used to train and validate machine learning models according to selections of additional features. The best performing machine learning models were then externally validated using data for all patients in the PMT trial. For comparison, 12 specialists provided predictions of metastatic disease using data from the training and external validation datasets. Prospective predictions indicated that plasma methoxytyramine could identify metastatic disease at sensitivities of 52% and specificities of 85%. The best performing machine learning model was based on an ensemble tree classifier algorithm that used nine features: plasma methoxytyramine, metanephrine, normetanephrine, age, sex, previous history of pheochromocytoma or paraganglioma, location and size of primary tumours, and presence of multifocal disease. This model had an area under the receiver operating characteristic curve of 0·942 (95% CI 0·894-0·969) that was larger (p<0·0001) than that of the best performing specialist before (0·815, 0·778-0·853) and after (0·812, 0·781-0·854) provision of SDHB variant data. Sensitivity for prediction of metastatic disease in the external validation cohort reached 83% at a specificity of 92%. Although methoxytyramine has some utility for prediction of metastatic pheochromocytomas and paragangliomas, sensitivity is limited. Predictive value is considerably enhanced with machine learning models that incorporate our nine recommended features. Our final model provides a preoperative approach to predict metastases in patients with pheochromocytomas and paragangliomas, and thereby guide individualised patient management and follow-up. Deutsche Forschungsgemeinschaft.

Composition analysis and antibacterial activity evaluation of different crude extracts of Mentha piperita (Lamiaceae)

Globally, the main target of scientists is to examine new medicinally beneficial plants for the preparation of herbal drugs as well as to explore possible uses in the food industry. In this regard, the target of our current study is to evaluate the antibacterial activity and biochemical analyses of the leaf extracts of Omani Mentha piperita L (M. piperita). The selected plant leaves coarse powder samples were extracted by using the Soxhlet extraction process with methanol at 65oC for a period of 72 hours. The evaporation of methanol was done by a rotary evaporator under reduced pressure and temperature. The hydro alcoholic extract was fractionated with the various polarities of solvents with an increasing pattern. The biochemical evaluation and pharmacological activity of the prepared local plant extracts were completed by using established methods. The different polarities of leaves extracts showed positive biochemical tests of alkaloids, flavonoids, glycosides, saponins, steroids, tannins and triterpenoids. The microbial activity of the fractioned plant extracts was tested with improved agar gel method. The different polarity extracts at different concentrations did not display any activity against the tested Gram (+) Staphylococcus aureus (S. aureus) and Gram (-) Escherichia coli (E. coli) and Pseudomonus aeruginosa (P. aeruginosa) bacterial strains. Based on the biochemical and pharmacological evaluation results, the selected whole plant and its potential extracts might be used traditionally as natural antibiotics to treat infectious diseases.

PSEUDOMONAS FLUORESCENS IN SHEEP MILK GREEK YOGHURT FROM VLASINA – A BIOCHEMICAL CHARACTERIZATION

Pseudomonas fluorescens is an aerobic, rod-shaped, non-sporulating gram-negative bacteria, mostlyfound in soil, decaying organic matter and feces. This species contaminates the milk mainly through animal feeddust, silage, utensils and polluted water. In addition to casein digestion, this psychotropic and lipolytic speciesgenerates butyric and caproic acids by fermentation of milk fat, which release a strong unpleasant odor and give arancid and bitter taste to dairy products. In this study we tested 48 hours old sheep's sour milk, produced in ahousehold in Vlasina, southeastern Serbia, using traditional method. Standard bacteriological protocols were usedfor isolation and identification Pseudomonas fluorescens strains. Biochemical identification was performed usingthe commercial API 32GN E system, and 60473057073 profile was obtained (Pseudomonas fluorescens, %Id=99.5and T=0.74). Positive biochemical tests were: N-acetyl-glukosamine (NAG), D-Ribose (RIB), Sodium malonate(MNT), Sodium acetate (ACE), Lactic acid (LAT), L-Alanine (ALA), D-Mannitol (MAN), D-Glucose (GLU), LArabinose(ARA), Capric acid (CAP), Valeric acid (VALT), Trisodium citrate (CIT), L-Histidine (HIS), Potasium2-ketogluconate (2KG), 3-Hydroxybutyric acid (3OBU), 4-Hydroxybenzoic acid (pOBE), L-Serine (SER), LProline(PRO) and Oxidase (OX). Negative biochemical tests were: L-Rhamnose (RHA), Inositol (INO), DSaccharose(SAC), D-Maltose (MAL), Itaconic acid (ITA), Suberic acid (SUB), Salicin (SAL), D-Melibose (MEL),L-Fucose (FUC), D-Sorbitol (SOR), Propionic acid (PROP), Potasium 5-ketogluconate (5KG), Glycogen (GLYG)and 3-hydroxybenzoic acid (mOBE). Based on the example of the strain Pseudomonas fluorescens, the API ID 32GN system proved to be precise and very efficient in the identification of this lipolytic type. Given thatpasteurization and cooling processes do not entirely inhibit the enzym activity and growth of this psychotrophicbacteria, informing individual milk and milk product manufacturers in the Vlasina region about good manufacturingpractices would limit contamination and bacteriological deterioration.

BIOREMEDIATION OF CRUDE OIL CONTAMINATED SOIL BY HYDROCARBON DEGRADING BACTERIA

Proficiency of hydrocarbon-degrading bacteria useful for eradicating soil pollution stimulated by seepage of petroleum and their derivative substances, therefore, sequestered different bacterial isolates were bear significant merits for utilizing hydrocarbons as an uncommon source of their growth and development. A colorimetric assay was performed at 595 nm wavelength which was subjected to the mineral salt broth with 1% oil (petrol, diesel, and burned out engine oil). This broth having minimum nutrients used by inoculated bacteria in which some isolates were adopted for taking a sufficient amount of either petrol, diesel, or burned-out engine oil as carbon source hence increases its turbidity that was measured in two days time interval up to twelve days of observation. We found that selected isolates were able to degrade burned out engine oil efficiently in contrast to petrol and diesel. At optical density 0.21± 0.13, 0.19±0.08, 0.18±0.09, 0.17±0.12 the result showed by isolatesBI-7, BI-2, BI-4, BI-6goodcompetency to degrade burned out engine oil. On the other hand, maximum diesel and petrol utilized by BI-2 &amp; BI-1 isolate at O.D. 0.09±0.02, 0.05±0.02 was recorded. Most of the bacterial isolates resulted in a positive biochemical test. BI-1 &amp; BI-7 resulted in positive starch hydrolysis test, whereas, all isolates resulted in positive urease test, simultaneously negative results for all isolates obtained when catalase and antibiotic sensitivity test against streptomycin were performed.

Isolation and culture medium optimisation using one-factor-at-time and Response Surface Methodology on the biodegradation of the azo-dye amaranth

Isolate JR1 was isolated from the polluted textile industry activities site in the Juru Penang area. This bacterium was characterized as a gram-positive Bacillus bacterium and also gave a positive biochemical test for catalase test and oxidase test. The isolate JR1 gave a maximum decolourization of Amaranth dye under static conditions with the rate of decolorization of 98.82%. Seven variables which are pH, temperature (°C), ammonium acetate (g/L), glucose (g/L), sodium chloride (g/L), yeast (g/L) and dye concentration (ppm) was run by using Plackett-Burman design for the effective parameter of the decolourization of Amaranth. From the seven variables, three effective variables which were ammonium acetate, glucose, and dye concentration were further optimized by using a central composite design. The optimum value of ammonium acetate concentration at 0.74 g/L, glucose concentration at 3.0 g/L and a dye concentration at 58.1 ppm gave the highest percentage of decolourization. Thus, this isolate could provide an alternate solution in removing toxic dyes from environments.

A plant growth promoting rhizospheric Pseudomonas aeruginosa strain inhibits seed germination in Triticum aestivum (L) and Zea mays (L)

Various rhizobacteria strains are isolated and tested worldwide for their plant growth promoting activities. A strain is said to be a plant growth promoter if it has the ability to influence plant growth directly or indirectly. Though the main focus has always been to realize the plant growth promoting traits of rhizobacteria and use them as biofertilizers, but the disadvantages or deleterious effects of such plant growth promoting rhizobacteria (PGPR) if any have also been ignored to a greater extent. The present study deals with the characterization of both promoting as well as deleterious activities of an isolated strain of Pseudomonas aeruginosa on plants. The bacterium was isolated from the soil of the college campus of Babasaheb Bhimrao Ambedkar University, Lucknow, Uttar Pradesh and was characterized as P. aeruginosa by various positive biochemical tests such as oxidase, catalase, citrate tests and confirmed by MALDI-TOF-MS. Its growth as well as IAA producing ability at different salt (NaCl) concentrations was tested. Tests examining HCN, Ammonia and siderophore production, flocculation ability, phosphate and zinc solubilization by the strain were carried out. Its anti-microbial property was tested against three phytopathogenic fungi: Fusarium solani, Aspergillus niger and Curvularia lunata and two bacterial strains - Klebsiella pneumoniae and E. coli. Its effect over seed germination of Triticum aestivum and Zea mays was inspected in plates as well as in pots. The strain showed a great potential as a plant growth promoter growing up to 10% NaCl concentration and producing considerable amount of IAA upto 8% NaCl concentration. It showed antagonistic nature against the three phytopathogenic fungi, solubilized phosphate and produced siderophore and NH3. Though supernatant of the bacterial culture did not show any deleterious effect over seed (of the test plants T. aestivum and Z. mays) germination but the seeds inoculated with the strain itself, failed to germinate. The seed turned dormant and grew a pale brown color showing bacterial growth over it. Thus it maybe concluded that the isolated strain of P. aeruginosa has abilities to both promote and at the same time inhibit plant growth (by inhibiting seed germination).

Эффективность пренатальной диагностики синдрома Дауна в шести областях Центрального и Юго-Восточного регионов Украины

Chromosomal aneuploidy (CA), having an incidence rate of 6-8 per 1000 live births, holds a special place in the structure of congenital and hereditary pathology. Among the common CA, trisomy 21 chromosomes (T21) is the most frequently found (its incidence rate in the general population amounts to 1:700–800 live births). The objective: to study the efficiency of prenatal screening of CA (Down’s syndrome, DS) in the areas under the Center’s operational activity in the period of 2010-2015; To estimate the actual prevalence of DS in terms of born and prenatally diagnosed, eliminated fetuses with T21; On the basis of retrospective analysis of indications for prenatal karyotyping, in all detected cases of DS, to specify their structure and incidence rate; Based on data from medical literature, to make a comparative analysis with similar studies in different countries around the world. Patients and methods. Over the six years (2010–2015) we have performed 3,137 invasive prenatal interventions, among which are 720 chorionic villus biopsies, 929 placententesises, and 1,488 amniocentesis of pregnant women having a high risk of CA, who were seeking medical help from our center whose operational activity covers 6 provinces (oblasts). Results. From 3,137 prenatally karyotyped studies, there have been found only 558 cases of fetal CA, including 288 fetuses with T21. A retrospective analysis of the structure of indications for invasive prenatal diagnosis in 288 pregnant women, having fetuses with prenatally detected DS, is presented as follows: – separate: only 40-aged and above mothers – 4 (1.38%); Ultrasound (US)-findings (anomalies and markers of CA) – 192 (69.5%); High biochemical risk of CA – 2 (0.7%). – combined: the mother’s age is 40 and above + US findings – 36 (13%); The mother’s age is 40 and above + US and biochemical (BC) markers – 8 (2.8%); Ultrasound findings + positive BC test – 32 (11.5%). Delivery of the previous child with DS by a pregnant woman under 40 years with no ultrasound and BC markers – 1 (0.34%). In total, ultrasound findings (anomalies and markers of CA) were found in 97.5% of cases of prenatally detected fetuses with DS. The index of prenatal detection of fetuses with Down syndrome of all registered karyotyped cases of T21 (pre- and postnatal) in the Dnepropetrovskaya oblast corresponds to the average European level - 65%, (in the areas of the center’s operational activity – 37.7%). Taking into account 242 cases of DS in fetuses aborted prior 22 weeks of gestation, the actual prevalence of T21 in case of their birth would be 1:766 (13 per 10.000 infants). Conclusions. Prevalence of Down syndrome among newborns in the Dnepropetrovskaya oblast as a result of prenatal diagnosis of chromosomal abnormalities makes 1: 1257, which is 1.8 times lower than the incidence in the average population (1:700); In other areas covered by the center’s consulting and diagnostic activity this rate is 1.1–1.55 times lower than that of the population one. In the absence of the existing system of prenatal diagnosis of Down syndrome, its average prevalence in these provinces would correspond to that of the general population 1:766 newborns. Key words: сhromosomal abnormalities, Down syndrome, prenatal screening strategies, ultrasound diagnosis, invasive prenatal diagnosis, ultrasound markers.

Antibiotic Resistance of Helicobacter pylori in Mazandaran, North of Iran

The aim of this study was to investigate the prevalence of resistances in Helicobacter pylori against commonly used antibiotics including metronidazole, clarithromycin, amoxicillin, and tetracycline in Iranian patients. H. pylori isolates were collected from gastric biopsies from patients referred for upper gastrointestinal endoscopy at Tooba Medical Center, Sari, Iran, from 2007 to 2010. None of them had been using antibiotics for at least 8 months. H. pylori was identified based on morphological shape and positive biochemical tests for catalase, oxidase, and urease activity. Antibiotic resistance for metronidazole, clarithromycin, amoxicillin, and tetracycline was investigated by using epsilometer test. Resistance was defined by minimal inhibitory concentration (MIC) > 0.5 mg/L for amoxicillin (AMX), >4 mg/L for tetracycline (TET), >8 mg/L for metronidazole (MTZ), and >1 mg/L for clarithromycin (CLR). Strains were collected from 132 patients, mean age 45.8 years, 52 (39%) were women. Patients had diverse diagnoses: gastritis 42 (31.8%), duodenal ulcer 45 (34%), gastric cancer 15 (11.3%), or gastric ulcer 30 (22.7%). The prevalences of resistance of H. pylori strains isolated from the patients were 73.4% for metronidazole, 30% for clarithromycin, 6.8% for amoxicillin, and 9% for tetracycline. Twenty-eight (21.2%) were double resistant to MTZ-CLR, 16 (12.1%) showed triple resistance to MTZ-CLR-AMX, and 8 (6%) were resistant to all four tested antibiotics (MTZ-CLR-AMX-TET). No associations were detected between multiple resistant strains and clinical manifestations (p > .05). The prevalence of H. pylori antibiotic resistance to metronidazole and clarithromycin was high in Iran consistent with the reported low success rates for H. pylori treatment in this country.

Trisomy 18: Fetal ultrasound findings at different gestational ages

The aim of this article is evaluate the sonograhic findings in fetuses with trisomy 18 at different gestational ages. The cases were recruited from pregnant women, who underwent to prenatal diagnosis in the period from October 1995 to September 2006. Seventy-one fetuses with trisomy 18 were diagnosed. On review of the sonograms the majority of these cases had ultrasound anomalies (sensitivity of 91.5%). The most frequent anomalies were abnormalities of extremities (40.8%) and fetal growth restriction (35.2%). More frequently (54.9%) two or more anomalies were present. Nearly all fetuses with trisomy 18 had sonographic abnormalities. Likely improved high-resolution equipment and attention to details by skilled operators led to the detection of most anomalies to trisomy 18. Knowledge of types of specific ultrasound findings can improve prenatal diagnosis in order to provide invasive procedures only when indicated, and to avoid amniocentesis when ultrasound signs are not observed in women at high risk from positive biochemical testing.

The economic implications of three biochemical screening algorithms for pheochromocytoma.

Pheochromocytoma is a rare, life-threatening condition. Using a modeling technique, we studied the economic implications of detection strategies for pheochromocytoma (third-party payer perspective). The diagnostic efficacy of biochemical tests was based on Mayo Clinic Rochester data. In all hypothetical algorithms, positive biochemical tests were followed by abdominal computerized tomography and, if negative, metaiodobenzylguanidine scintigraphy. In each hypothetical algorithm, imaging would be indicated after positive biochemical testing as follows: algorithm A, fractionated plasma metanephrine measurements above the laboratory reference range; or algorithm B, abnormal measurements of 24-h urinary total metanephrines or catecholamines. In algorithm C, subjects with fractions of plasma metanephrine at or above 0.5 nmol/liter or normetanephrine at or above 1.80 nmol/liter would undergo imaging, whereas those with values between the reference range and these cutoffs would undergo 24-h urinary measurements (total metanephrines and fractionated catecholamines) and be imaged if positive. We determined that, if 100,000 hypertensive patients (including 500 patients with pheochromocytoma) were tested, algorithm A (measurement of fractionated plasma metanephrines alone) would detect 489 pheochromocytoma patients at a cost of 56.6 million dollars, whereas B (24-h urinary measurements) would detect 457 pheochromocytoma patients for 39.5 million dollars, and C (combination of measurements of fractionated plasma metanephrines and urines) would detect 478 patients for 28.6 million dollars. None of the screening strategies for pheochromocytoma described are affordable if implemented on a routine basis in extremely low-risk patients. However, algorithm C may be the least costly, and at a reasonable level of sensitivity, for subjects in whom the suspicion of disease is moderate.

False Positive Biochemical Testing for Pheochromocytoma Caused by Surreptitious Catecholamine Addition to Urine

False Positive Biochemical Testing for Pheochromocytoma Caused by Surreptitious Catecholamine Addition to Urine

Progrès récents dans le diagnostic, l’évaluation pronostique et le traitement des phéochromocytomes

Introduction. – Pheochromocytoma is a catecholamine-secreting neoplasm of chromaffin tissue. It is a rare disease. Biochemical tests should be performed only in patients at high risk of pheochromocytoma, and an imaging procedure only in those with positive biochemical tests. Current knowledge and key points. – The most specific and sensitive diagnostic test for the disease is the determination of plasma or urinary metanephrines. The tumor can be located by computerized tomography, magnetic resonance imaging, and specific scintigraphy. Ten to 20% of pheochromocytomas result from hereditary diseases, including multiple endocrine neoplasia type 2, von Hippel Lindau disease, and neurofibromatosis 1. Familial cases are diagnosed earlier, and are more frequently bilateral and recurring than sporadic cases. About 10% of the cases are malignant either at first operation or during follow-up, malignancy being diagnosed by the presence of lymph node, visceral or bone metastases. The probability of a recurrence is positively correlated with the urinary excretion of metanephrines and tumor size. Recurrences are more frequent in cases with ectopic tumors and in those with a low plasma epinephrine to total catecholamine ratio. Patients, especially those with familial tumors or low epinephrine secretion, should be followed-up indefinitely. Future prospects and projects. – Treatment for malignant recurrences includes surgery, therapeutic embolization, chemotherapy, and the application of therapeutic doses of metaiodobenzylguanidine. Metyrosine, phenoxybenzamine, or somatostatin analogs may help to control blood pressure and to alleviate symptoms in patients with malignant pheochromocytoma; however such a treatment has no antiproliferative effect.

Results of routine fetal nuchal translucency measurement at weeks 10–13 in 4233 unselected pregnant women

The aim of this study was to determine the value of nuchal translucency (NT) measurement for the detection of aneuploidies and other malformations in a low-risk population. In total, 4233 women who booked in our hospital for delivery were examined between the tenth and 13th week of gestation. Of the 17 chromosomal abnormalities that occurred, 11 were detected using the measurement of NT (65 per cent). Only three of the seven Down syndrome pregnancies were detected using this technique (43 per cent). The remaining four Down syndrome babies were diagnosed either because of positive biochemical testing or by amniocentesis because of maternal age. A total of 69 serious malformations including chromosomal defects were detected during the study period. In 18 of these cases, the NT measurement was > or = 2.5 mm (26 per cent). Most of the malformations without aneuploidies were of cardiac origin. The data show that the NT measurement is a valuable marker for aneuploidy even in a low risk-population. It is also of value in the diagnosis of other serious malformations, particularly cardiac defects.

Recurrent pheochromocytomas in children

Between 1958 and 1987, 13 children (aged 8 to 17 years) with 20 pheochromocytomas were diagnosed and treated. Five of these 13 had multiple (12) tumors and four patients had five recurrences in 6 years (1980 to 1986). There were three girls and one boy between 8 and 15 years of age. One girl had von Hippel-Lindau disease. Three of four original tumors were adrenal and less than 6 cm in diameter. All were excised without complications and went home normotensive. The five recurrent tumors were diagnosed and treated within 6 years of the original tumor when the children were 9 to 17 years; their presenting symptoms and signs (3 months) were hypertension plus others, not necessarily the same as previously. Computed tomography scan was again positive in the three that had this test; vanillylmandelic acid was the only uniformly positive biochemical test. Norepinephrines were positive in the three patients examined. The three girls had their recurrent tumors found in the opposite adrenal and the boy once again had two more tumors (adrenal and chest); all tumors were less than 3 cm in diameter and easily excised. They remain normotensive and well up to 8 years. Within this small group of recurrences, there was no specific pattern that would have led one to suspect that they would return with another pheo. There was nothing unusual about their recurrent tumor, except that it was usually in the opposite adrenal; only one of the four children has no remaining adrenal tissue. Although follow-up is important, recurrent pheochromocytomas seem to be heralded by recurrent symptoms and signs of hypertension.

Vibrio cincinnatiensis sp. nov., a new human pathogen

A halophilic gram-negative rod was isolated from blood and cerebrospinal fluid collected from a 70-year-old male having no known contact with seafood or salt water. Positive biochemical tests included oxidase, sensitivity to 0/129, O-nitrophenyl-beta-D-galactopyranoside, lysine decarboxylase and fermentation of glucose, salicin, n-inositol, sucrose, L-mannose, L-arabinose, and arbutin. Negative tests included indole, ornithine decarboxylase, arginine dihydrolase fermentation of lactose, and production of gelatinase and urease. The DNA base composition was 45.0 mol% guanine plus cytosine. Numerical taxonomy indicated 70% similarity with known reference Vibrio sp. strains. The 5S rRNA sequence for this strain has been determined: 5'-U G C C U G G C G A C C A U A G C G U U U U G G A C C C A C C U G A U U C C A U G C C G A A C U C A G U A G U G A A A C G A A A C A G C G U C G A U G G U A G U G U G G G G U C U C C C C A U G U G A G A G U A G A A C A U C G C C A G G C A U-3'. Based on the phenetic, molecular genetic, and nucleic acid sequencing data, it is concluded that Vibrio cincinnatiensis represents a new species of the genus Vibrio sensu strictu (as defined by 5S rRNA sequencing results). On a basis of 5S rRNA comparative sequence analysis, the organism appears to share a recent common ancestor with V. gazogenes (98% homology) and close ancestry with V. mimicus, V. fluvialis, and V. metschnikovii.

Hookworm Disease and Malabsorption

Summary Fourteen patients with hookworm disease were studied for evidence of malabsorption. In these patients steatorrhea and positive biochemical tests were found, as well as pathologic and roentgenographic abnormalities of the small bowel. Similar evidence of malabsorption was absent in 6 asymptomatic patients with similar parasitic infestation and in 8 persons infested with parasites other than hookworm.