[Hematuria in the child. Investigation plan in pediatric practice]

The discovery of hematuria in a child should lead the pediatrician to a methodical evaluation of the patient based on an extensive history and comprehensive physical examination. The microscopic examination of the urine is the cornerstone in the evaluation process and may suggest the origin of the hematuria. For instance, red blood cell casts indicate glomerular lesions and rule out the need for further urological examinations. According to the type of hematuria and the associated symptoms, a complete and immediate evaluation is sometimes necessary. This article presents a decisional tree to help the pediatrician to investigate an hematuria and to refer the child to a specialist, when needed.

Scopolamine-induced cognitive impairment as a predictor of cognitive decline in healthy elderly volunteers: a 6-year follow-up

OBJECTIVE

To determine if scopolamine-induced cognitive impairment in healthy elderly people predicts cognitive decline 6 years later.

DESIGN

Prospective cohort study.

SETTING

Elderly care research unit.

PARTICIPANTS

Healthy elderly people who were part of a volunteer panel of research subjects.

INTERVENTIONS

Scopolamine 0.2 mg administered subcutaneously at baseline.

MAIN OUTCOME MEASURES

Cognitive drug research computerized cognitive testing battery pre- and post-scopolamine, with repeat testing over 6 years later.

MAIN RESULTS

16/24 subjects were retested. Although marked decrements in cognitive functioning were seen with scopolamine, there was little change in performance over 6 years, and no significant association was seen between scopolamine-induced decrement and change over time.

CONCLUSIONS

The scopolamine challenge test is not likely to play a role in the preclinical diagnosis of Alzheimer's disease.

A family study of autism: cognitive patterns and levels in parents and siblings

First-degree relatives of 99 autism probands and of 36 Down's syndrome controls were assessed with standardised tests of intellectual functioning, reading, and spelling. Higher mean verbal IQ scores, and discrepancies in favour of verbal scores, were characteristic of autism relatives. No consistent differences were found on performance scales, reading, and spelling tests. Among autism relatives, siblings affected with the broad phenotype of autism had significantly lower IQ scores and poorer reading and spelling performances than unaffected siblings. However, the small size of the cognitive difference and the lack of a distinctive cognitive profile indicates that standardised cognitive measures used in this study are unlikely to improve the operationalised definition of the broad phenotype of autism. The slightly superior verbal performance of relatives in the autism group might represent some form of heterozygote advantage.

Rapid detection of deletions causing delta beta thalassemia and hereditary persistence of fetal hemoglobin by enzymatic amplification

A considerable number of deletions of variable size and position that involve the beta-globin gene complex on chromosome 11 are associated with the clinical entities of hereditary persistence of fetal hemoglobin (HPFH) and delta beta thalassemia. Specific deletions appear to be associated with consistent phenotypes and some are known to be recurrent. To facilitate the molecular diagnosis of uncharacterized patients with HPFH and delta beta thalassemia, oligonucleotide primers have been designed to enzymatically amplify deletion-specific products for nine known deletions, which include those responsible for HPFH-1, HPFH-2, HPFH-3, Spanish (delta beta)zero thalassemia, hemoglobin (Hb) Lepore, Sicilian (delta beta)zero thalassemia, Chinese G gamma(A gamma delta beta)zero thalassemia, Asian-Indian inversion-deletion G gamma(A gamma delta beta)zero thalassemia, and Turkish inversion-deletion (delta beta)zero thalassemia. Using this approach, we have successfully characterized the molecular basis for delta beta thalassemia in 23 individuals from 16 families of diverse ethnic origins. Thirteen individuals from this group were shown to be heterozygous for the 13.4-kb Sicilian deletion, two were heterozygous for the 100-kb Chinese G gamma(A gamma delta beta)zero deletion, four were heterozygous for the Turkish form of inversion-deletion delta beta thalassemia, and three were heterozygous for the Asian-Indian form of inversion-deletion G gamma(A gamma delta beta)zero thalassemia. One Vietnamese subject was heterozygous for a 12.6-kb deletion, which we have fully characterized at the molecular level. Sequence analysis of the breakpoint regions of the Chinese deletion and the Turkish rearrangement indicates that, in each case, the mutation is likely to have arisen from a single origin. This hypothesis is supported by the evident geographical clustering of the various deletions described here.

Peptidyl fluoromethyl ketones as inhibitors of cathepsin B. Implication for treatment of rheumatoid arthritis

Peptidyl fluoromethyl ketones (FMKs), with the amino acid sequence Phe-Ala held constant but with variable N-terminal groups, were synthesized and tested for inhibition of the cysteine proteinase cathepsin B. The FMKs were effective in inhibiting cathepsin B activity in vitro. The inhibition was time dependent and was not reversed by dialysis, suggesting covalent modification of the enzyme. Cathepsin B activity present in livers and kidneys of rats treated with FMKs was reduced by 22-91% 4 hr after a single oral dose of 25 mg/kg. The FMKs inhibited the severity of inflammation and the extent of cartilage and bone damage in adjuvant-induced arthritis. These effects were seen during the late-stage of the disease with no effect on onset or incidence of disease. This is consistent with inhibition of protease-mediated damage. These FMKs or derivatives may be of clinical value in the treatment of arthritis.

Lack of deleterious effect of slow-release sodium fluoride treatment on cortical bone histology and quality in osteoporotic patients

We evaluated the effects of intermittent slow-release sodium fluoride (SRNaF) and continuous calcium citrate therapy on cortical bone histology, reflection ultrasound velocity (material strength) and back-scattered electron image analysis (BEI) in 26 osteoporotic patients before and following therapy. All measurements were made on transiliac crest bone biopsies obtained before and following 2 years of therapy in each patient. For all 26 patients there were no significant changes in cortical bone histomorphometric parameters. In 15 patients in whom bone material quality was assessed by reflection ultrasound, there was no change in velocity (4000 +/- 227 SD to 4013 +/- 240 m/s). BEI disclosed no mineralization defects or the presence of woven bone. Mean atomic number (density) of bone increased slightly, but significantly (9.261 +/- 0.311 to 9.457 +/- 0.223, P = 0.031). While these changes are less marked than those observed for cancellous bone, they indicate that this form of therapy does not adversely affect cortical bone remodelling.

One year of rHuEPO therapy prolongs RBC survival and may stabilize RBC membranes despite natural progression of chronic renal failure to uremia and need for dialysis

rHuEPO was administered to eight patients with chronic renal failure (CRF) and uremia (U) for 1 year. Creatinine Clearance (GFR) averaged 14.3 (9-25) ml/min at an Hct of 28% (26-30). Baseline RBC survival by 51Cr T1/2 was highly correlated with GFR (r = 0.66), p less than 0.05 (2), average 21.6 days. Repeat 51Cr T1/2 at 3 months with GFR 10 ml/min at Hct 38% was prolonged by 7 days to 28.6 (p less than 0.005), and at 1 year remained increased to 28 days (p less than 0.001) with Hct 39%, despite further decreased GFR to less than 4 ml/min and need for dialysis. Reticulocytes varied from 1.6% to 7.4 (3-6 weeks) to 3.1 (3 months) and 1.5% (1 year). Bone marrow cellularity increased from 36% to 47% (3 months) and 44% (1 year). M:E ratio decreased from 3.9:1 to 1.7:1 (3 months) to 1.6:1 (1 year). Marrow iron decreased from 4.1/6 to 2.4/6 (3 months) to 1.8/6 (1 year). Doses of rHuEPO had to be reduced to avoid polycythemia. rHuEPO stimulates erythropoiesis in pts with progressive CRF and U for 1 year. The initial increase in hematocrit is due to the early peak of reticulocytes. At 3 months, rHuEPO maintains the increased hematocrit by three mechanisms: 1) increased reticulocytosis, 2) a trend to increased bone marrow erythroid cellularity, and 3) lengthened RBC survival. At 1 year of rHuEPO therapy, the trend to increased marrow cellularity persists, however, the maintenance of target hematocrit is via a lengthened RBC survival. Despite progression of CRF and U, rHuEPO produced RBCs with longer survival than expected. RBC membranes may have been stabilized by rHuEPO.

INTERRELATIONSHIPS BETWEEN ASPECTS OF NITROGEN METABOLISM AND SOLUTE ACCUMULATION AND THE DISTRIBUTION OF SUBTROPICAL WOODY PLANTS IN SOUTHEAST AFRICA

Little is known of the mechanisms governing nitrogen metabolism and stress tolerance in woody plants of subtropical southeast African savannas, although many of the more widely occurring genera, particularly Acacia and Combretum species, include valuable multi-purpose trees. Basal nitrate reductase activities in vigorous leaves from 59 species and five savanna areas were used as a measure of nitrate availability. Consistently low activities were found in many of the legumes and in members of the Combretaceae. When shoots from 35 of these same species were provided with supplementary nitrate solution, increased reductase activity was recorded in a number of taxa, including non-nodulating legumes belonging to the Caesalpinioideae. Nodulating legumes did not behave in the same way. Either proline or quaternary ammonium compounds, examples of stress metabolites, accumulated in the shoots of a range of taxa belonging to a number of families. The highest concentrations occurred in shoots collected from the driest areas. Amounts of tannin were high in some species but showed no consistent pattern.

Iatrogenic posterior tibial neurothlipsis: a tarsal tunnel syndrome

Posterior tibial neurothlipsis in the retromalleolar space, secondary to internal fixation of a prior ankle fracture, is presented in the following report. The possibility of a tarsal tunnel syndrome cannot be ruled out. No apparent similar reference is made in the medical literature concerning the above etiology of posterior tibial compression/neurothlipsis/tarsal tunnel syndrome. Electrodiagnosis with sensory nerve conduction velocities is reviewed for more accurate diagnosis of tarsal tunnel syndrome.

Bioavailability, pharmacokinetics, and clinical effects of an oral preparation of etoposide

Bioavailability of an oral preparation of the antineoplastic drug etoposide (VP-16) was studied in 13 patients with advanced malignancies. An initial pilot study involving three patients suggested that approximately 50% of an orally administered dose was absorbed. Ten additional patients were randomized to receive either 100 mg/m2/day iv or 200 mg/m2/day orally. Three weeks later, the alternate dose schedule was administered. Plasma samples were assayed for VP-16 using a high-pressure liquid chromatography technique. Comparison of the area under concentration-time curves (C X t) revealed that 17%-72% (mean, 52%) of an orally administered dose was absorbed. Absorption was less than 40% for only one patient. For oral and iv preparations, mean peak plasma VP-16 concentrations were 9.6 and 13.0 micrograms/ml, mean alpha-half-lives were 0.96 and 0.82 hour, mean beta-half-lives were 7.2 and 6.8 hours, mean C X t values were 75.9 and 75.3 mg/L/hour, mean plasma clearances were 1.44 and 1.45 L/hour/m2, and mean extrapolated volumes of distribution were 15.2 and 16.9 L/m2, respectively. The half-life for oral absorption was 0.44 hour and peak plasma concentrations were noted 0.5-3 hours after oral drug administration. Granulocyte count nadirs tended to be lower in patients with high C X t values and low plasma clearance values. Granulocytopenia was dose-limiting. Gastrointestinal toxicity was extremely mild. We recommend doses of oral VP-16 of 800 mg/m2/course over 3-5 days for patients with a moderate amount of prior treatment. It is probable that previously untreated patients will tolerate a higher dose and that heavily pretreated patients will require a lower dose.

Penetration of teniposide (VM-26) into human intracerebral tumors. Preliminary observations on the effect of tumor type, rate of drug infusion and prior treatment with amphotericin B or oral glycerol

Thirty-four consenting patients received VM-26 50-100 mg/m2 I.V. before surgical resection of intracerebral tumor, and drug was measured using a high pressure liquid chromatographic technique. Sufficient tumor for analysis was obtained from 29 patients. Brain metastases (13 patients) had higher concentrations of VM-26 than did gliomas (13 patients). Concentrations were comparable in brain metastases and meningiomas (3 patients). Prolonged (24 h) infusion of VM-26 did not appear to result in higher tumor drug concentrations in 5 patients than did rapid (1 h) infusion in 24 patients. Pretreatment with Amphotericin-B 10 mg/m2 12 h and 1 h before VM-26 did not appear to have any effect on VM-26 uptake into 4 intracerebral tumors, although data were limited, and VM-26 concentrations were very high in 1 metastasis. Pretreatment with oral glycerol 500 mg/kg 18 h, 12 h, 6 h, and immediately before I.V. VM-26 may have resulted in increased penetration of VM-26 into 9 tumors, although confirmation is required. Amphotericin-B, glycerol, and operative conditions did not appear to alter VM-26 plasma pharmacokinetics.

Penetration of VP-16 (etoposide) into human intracerebral and extracerebral tumors

VP-16 100 mg/m2 was given intravenously to 10 patients undergoing surgical resection of intracerebral tumors, and the drug was assayed in resected tumor using high pressure liquid chromatography. VP-16 concentrations varied from undetectable (less than .1 microgram/g) to 5.9 micrograms/g (mean, 1.4 microgram/g). VP-16 concentrations in tumors were lower than concurrent plasma concentrations. In addition, intracerebral tumors had a lower concentration of VP-16 than did extracerebral tumors (mean VP-16 concentration, 3.9 micrograms/g) from 7 patients receiving VP-16 50-100 mg/m2 intravenously. Plasma pharmacokinetics of VP-16 were different in our patients with intracerebral tumors than in previously studied patients with extracerebral tumors and it is unclear what role this may played in variability of tumor VP-16 concentrations. VP-16 concentrations were similar in glioblastomas and brain metastases. Specimens from patients with small cell undifferentiated carcinoma of the lung had the highest VP-16 concentrations. A patient who had both viable and necrotic tumor resected during an occipital lobectomy had a higher drug concentration in the necrotic than in the viable area of tumor. In addition, VP-16 concentration decreased as a function of distance into brain from the tumor. Based on our data, VP-16 might be expected to have less activity against intracerebral than against extracerebral human tumors.

Celiac disease in monozygous twin boys. Asynchronous presentation

A 13-year-old boy presented when his weight gain fell behind that of his monozygous twin brother. Following investigation, he was found to have gluten-sensitive enteropathy on jejunal biopsy. Investigation of his symptom-free brother showed biopsy evidence of the condition with changes similar to those of the clinically affected boy. Following treatment with a gluten-free diet, the boys achieved a similar weight after 15 months.

Respiratory oscillations in arterial carbon dioxide tension as a control signal in exercise

We have monitored oscillations in arterial pH (of respiratory frequency) in normal man at rest and during exercise. The pH oscillations are known to reflect respiratory oscillations in arterial carbon dioxide tension generated at the lungs. We have found that the pH oscillations increase in their upslope and downslope during exercise. This means that oscillations in arterial carbon dioxide tension can be considered as a control signal.