Onset of auditory deprivation

The purpose of this investigation was to study further the assertion that auditory function deteriorates in the unaided ear of individuals with sensorineural hearing loss (SNHL) who receive monaural hearing aid fittings. The word recognition scores (WRSs) of 77 monaurally and 65 binaurally fitted subjects with symmetric bilateral SNHL were examined at 1, 3, and 5 years post hearing aid fitting. The deterioration in auditory function was defined as a significant change in the WRSs for Northwestern University Auditory Test No. 6 (NU-6) materials in the unaided ear of individuals fitted with a monaural hearing aid arrangement. Analyses of the data indicate that 25 percent of the monaurally fitted subjects experienced a significant change in the WRSs of their unaided ears, whereas only 6 percent of the binaurally fitted subjects experienced a significant change in the WRSs of either ear. Auditory function does deteriorate in the unaided ears of individuals with SNHL who receive monaural hearing aid fittings. Moreover, the decline in auditory function of the unaided ear does not result from a decrease in hearing sensitivity.

Is the unaided ear effect independent of auditory aging?

As a group, adults with bilateral symmetric sensorineural hearing loss (SNHL) who receive a monaural hearing aid fitting experience a progressive decline in their word recognition score (WRS) for monosyllabic word materials in the unaided ear but not in the aided ear. However, adults with binaural fittings do not demonstrate a similar deterioration in their WRS. In an effort to determine the role of senescent auditory changes on the unaided ear effect, a retrospective investigation was carried out on a group of hearing aid wearers. Using NU-6 to assess the WRS, this investigation attempted to answer the following question: is the unaided ear effect related to asymmetric senescent auditory changes? The present results indicate that the unaided ear effect is not related to such an asymmetric effect since it is shown to occur in adults with SNHL whether in the fourth or seventh decade of life.

Effectiveness of three central auditory processing (CAP) tests in identifying cerebral lesions

The effectiveness of three central auditory processing (CAP) tests was evaluated using clinical decision analysis (CDA) procedures. The tests under study were the Dichotic Digits Test (DDT), the Auditory Duration Patterns Test (ADPT), and the P300 evoked potential test (P300). Subjects with normal hearing, sensorineural hearing loss (SNHL), and central lesions provided the data for CDA analyses. To identify the most effective test, we used the conventional CDA parameters of hit rate (sensitivity), false-positive rate (1 - false-positive rate = specificity), and A' (test performance at specific hit/false-positive combinations). Further, we illustrated the extension of the conventional CDA parameters to posterior probability determination, which incorporates disorder prevalence to compute the likelihood of a patient having a disorder when a test result is positive (Pr[D/+]) or not having a disorder when the test result is negative (Pr[N/-]). Last, we used the CDA parameter of hit rate and disorder prevalence to determine cost effectiveness.

Validity of the ipsilateral acoustic reflex as a screening parameter

Historically, the ipsilateral acoustic reflex (IAR) has played a prominent role in middle ear screening protocols. However, in 1990, the American Speech-Language-Hearing Association's revised guidelines, "Screening for Hearing Impairment and Middle Ear Disorders," deleted the IAR as a screening parameter. This decision was based on studies that demonstrated that the inclusion of the IAR resulted in a high false-positive rate without adding to the hit rate and thus was a major contributor to over-referral. However, other investigations demonstrated the converse, that the IAR is a sensitive and contributory measure in a screening protocol. Our data suggest that the conflicting results are due to different operating systems in the middle ear analyzers that were used to elicit the IAR. Based on our findings, an optimal IAR screening protocol would use a pulsed elicitation immittance system (multiplexing circuit) and a maximum intensity level of 105 dB HL. Further, if the IAR screening were to be carried out using an automated (programmed) immittance system with an equivalent volume change criteria for IAR detection, the equivalent volume change of > or = 0.03 ml is recommended.

Escherichia coli verotoxin binding to human paediatric glomerular mesangial cells

Haemolytic uraemic syndrome (HUS) remains the leading cause of acute renal failure in children. Although an Escherichia coli-produced verotoxin (VT) has been implicated in the pathogenesis of HUS, the precise mechanisms of disease are not well defined. We hypothesise that the pathogenesis of renal failure in HUS includes the binding of E. coli VT to the glomerular mesangial cell, with consequent effects on renal function. Using human paediatric mesangial cells, we studied the binding and biological effects of the purified verotoxin VT-1. We isolated, purified and characterised paediatric glomerular mesangial cells. The mesangial cells were characterised by their immunoreactivity with both smooth muscle actin and vimentin antibodies, and lack of immunoreactivity with cytokeratin or factor VIII antibodies. Using an fluorescein isothiocyanate-conjugated VT (10(-7)-10(-8) M), we demonstrated specific binding to the mesangial cell membrane by immunofluorescence microscopy. We also demonstrated a dose-dependent inhibition of mesangial cell mitogenesis at concentrations from 10(-9) to 10(-17) M. Our data demonstrate that VT-1 binds to paediatric human glomerular mesangial cells and this binding results in specific biological actions, including an inhibition of cell mitogenesis.

Airbag deployments: the Canadian experience

Transport Canada is undertaking an in-depth study of motor vehicle collisions involving airbag deployments. University-based collision investigation teams across Canada are used to collect crash data. The primary objective of the study is to gain a better understanding of the injuries and the injury mechanisms associated with airbag deployments among both restrained and unrestrained occupants. Preliminary results show an exceptionally high level of seatbelt use in conjunction with the supplemental air cushion restraints. Most crashes are, however, of only minor to moderate severity, in which the seatbelt systems alone would be expected to provide adequate occupant protection. Initial findings indicate that, at the lower end of the collision severity spectrum, deployment of an airbag may, in some circumstances, increase the overall likelihood of injury to a restrained occupant. This suggests that the current deployment threshold is set too low, at least for belted occupants.

Acoustic neuroma in an adolescent without neurofibromatosis: case study

When acoustic neuromas are found in younger age groups, they are typically bilateral and associated with neurofibromatosis (NF). A unilateral acoustic neuroma in a child or adolescent without NF is rare. We report audiometric, auditory brainstem response (ABR) and magnetic resonance imaging (MRI) data for a 15-year-old male with an acoustic neuroma but without associated NF. The patient was seen for audiologic assessment on three separate occasions over a period of 5 years. The first two assessments produced unremarkable audiometric and immittance data. The third assessment, subsequent to a failed school hearing screening, demonstrated a flat unilateral sensorineural hearing loss, unilateral absent acoustic reflexes, and abnormal bilateral ABR recordings. MRI with contrast demonstrated a unilateral mass extending out of the internal auditory meatus. Microscopic examination of the removed tumor confirmed a vestibular schwannoma. An enhanced MRI 3 years post neuroma removal demonstrated no evidence of tumor regrowth and no evidence of other neoplasms. ABR recordings for the uninvolved ear continued to demonstrate neural synchrony as evidenced by normal absolute wave latencies; however, the III-V and I-V interwave latencies remained extended beyond the 99th percentile. Postoperatively, the young man was fitted with a high gain in-the-ear hearing aid in the involved ear, which he has continued to wear on a daily basis for the past 3 years.

Effectiveness of transient-evoked otoacoustic emissions (TEOAEs) in predicting hearing level

The purpose of the present investigation was to (1) determine the short-term test-retest reliability of the transient-evoked otoacoustic emission (TEOAE) parameters of echo level and reproducibility, as produced by the Otodynamic's ILO88 system; and (2) assess the ability of the ILO88 parameters of frequency spectrum, echo level, and reproducibility to identify ears with sensorineural hearing loss. Our results show that the short-term test-retest reliability for both echo level and reproducibility is excellent, reflecting the stability of TEOAEs and the low measurement error associated with the procedure for obtaining TEOAEs. The data suggest, however, that frequency-specific hearing levels (HLs) cannot be accurately predicted from the analogous frequencies depicted in the frequency spectrum produced by the ILO88 system. Although frequency-specific HLs cannot be predicted from the frequency spectrum, the parameters of echo level and reproducibility will clearly separate individuals with HLs < or = 20 dB from individual with HLs > 20 dB for the octave frequencies of 500-4000 Hz. An echo level of < 6 dB and/or a reproducibility value of < 70 percent are associated with HLs > 20 dB between 500 and 4000 Hz. The combination criterion of an echo level of < 6 dB and a reproducibility value of < 70 percent appears to be a suitable screening method for identifying adult ears with an average HL of > 20 dB.

Monaural hearing aid effect: case presentations

A phenomenon associated with a monaural hearing aid fitting has previously been identified. In some individuals with bilateral sensorineural hearing loss (BSNHL), the speech-recognition score (SRS) of the unfitted ear deteriorates over time. Nine subjects with BSNHL who chose a monaural hearing aid fitting are chronicled from the time of their initial hearing fitting to the time where the SRS of the unfitted ear dropped below the lower limit of the 95 percent critical difference value. All nine of the subjects were fitted with binaural amplification at the time of the significant change in the SRS. Five of the subjects retained the binaural amplification arrangement while three of the subjects returned their second hearing aid after a "30 day trial," and one subject stopped wearing the second hearing aid 8 months after the binaural fitting. All the subjects who chose to utilize the binaural arrangement had their SRS return to within the 95 percent critical difference range as did two of the individuals who chose to retain the monaural arrangement.

Lactic acid changes during and after hypothermic cardiopulmonary bypass in infants

Infants undergoing open-heart surgery with hypothermic cardiopulmonary bypass experience markedly elevated lactate and glucose levels. Reports in infants less than 10 kg show the elevated lactate to be progressive during the operative period. The pathogenesis of the hyperglycemia is not clear but may be caused by excess glucose administration, inadequate insulin response, or glucose regulatory hormone levels of glucagon, cortisol, and growth hormone. The purpose of this study is to confirm these findings and to investigate their pathogenesis. Serial blood samples were taken preoperatively, intraoperatively, and postoperatively during hypothermic cardiopulmonary bypass in nine infants of less than 10 kg. Samples were analyzed for levels of lactate, glucose, and regulatory hormones insulin, growth hormone, glucagon, and cortisol. Our study did not show a progressive accumulation of lactate. The elevated lactate level appears to come from the pump prime solution. The hyperglycemia is also from the pump prime solution, and there do not appear to be elevated levels of regulatory hormones intraoperatively. Insulin response during hypothermia is blunted; however, on rewarming the patient in the immediate postoperative period, a brisk insulin response is seen. The changes in levels of lactate and glucose and the regulatory hormones return to baseline at 24 hours with no further significant changes in the next 48 hours.

Lipopolysaccharide alters suckling rat liver glycogenolysis

Gram-negative sepsis/septic shock in the newborn continues to be a major medical problem, causing high mortality. Hyperglycemia followed by hypoglycemia is a common symptom in endotoxic shock. However, the mechanism of newborn glucoregulatory response to endotoxin has not been well understood. Paradoxically, monocyte-phagocytes can contribute to shock by overwhelming secretion of cytokines and also host defense by detoxifying endotoxin. Since monocyte-phagocyte function is immature in the newborn, this study was performed to evaluate Kupffer cell's role in liver glycogenolysis during endotoxic shock. Endotoxin (LPS) induced hyperglycemia in 10-day-old rats, and increased net glucose output in the isolated perfused liver. 1) Cytarabine decreased Kupffer cell function (decreased hepatic colloid carbon uptake) and blunted LPS-increased liver net glucose output in the Cytarabine + LPS-treated group (104 +/- 4 vs. 146 +/- 3 micrograms/min/g wet liver in the LPS-treated group: P < .001). 2) Indomethacin (IND) suppressed LPS-induced liver net glucose output in the LPS + IND-treated group (133 +/- 5 vs. 146 +/- 3 micrograms/min/g wet liver, P < .05). Thus, prostaglandins were suggested to contribute to glycogenolysis in the 10-day-old rat liver. 3) Phorbol 12-myristate 13-acetate (PMA) increased liver net glucose output (166 +/- 4 micrograms/min/g wet liver), and H-7, a protein kinase C inhibitor, blunted PMA-induced liver glucose output (140 +/- 2 micrograms/min/g wet liver, P < .05). H-7 enhanced LPS-induced liver net glucose output (196 +/- 9 micrograms/min/g wet liver, P < .01). Therefore, protein kinase C may not be the dominant cell signaling system for LPS stimulation in suckling rat Kupffer cells.

Assessment of renal function in the young. Special considerations

Infants are born in a state of renal insufficiency and have varying degrees of maturity of tubular processes. This is even more striking in premature infants. This article presents a review of glomerular and tubular function assessment with particular attention to factors that impact these developmental and maturational factors.

Glycosuria and maternal licking in rats

Maternal anogenital licking (MAGL) has been studied to understand the mechanism of maternal behaviour. The present study showed that rats had glycosuria at the concentration of 18-20 mg/dl and glucose was the preference of postpartum rats. MAGL increased on suckling rats separated for 24 h. However, wiping anogenital region attenuated the increase of MAGL. Therefore, glucose preference of postpartum rats may be involved in MAGL.

Diltiazem treatment of endotoxic shock in suckling rats

Gram-negative sepsis septic shock continues to produce significant mortality and therefore remains a major medical problem. Vasodilators have been studied in the treatment of circulatory shock. However, the effectiveness of calcium channel blockers in the treatment of newborn endotoxic shock has not been well documented. In the present study, diltiazem, a calcium channel blocker, and nitroprusside, a vasodilator, were used for the treatment of endotoxic shock in 10-day-old rats. Mortality rate, hemodynamics, and glucose metabolism were monitored. Diltiazem at a dose of 0.3 mg/kg attenuated the hypotension, bradycardia, hypoglycemia, and lactacidemia in newborn endotoxic shock. Diltiazem treatment resulted in reduced 24-hour mortality. However, 0.6 mg/kg diltiazem enhanced the hypotension, bradycardia, and lactacidemia in endotoxic shock. Nitroprusside blunted the hypoglycemia and decreased the mortality rate among rats with endotoxic shock. Afterload reduction may be responsible for the beneficial effects of 0.3 mg/kg diltiazem and nitroprusside. Diltiazem at a dose of 0.3 mg/kg reduced the lactacidemia of endotoxic shock more than nitroprusside. Therefore the effects of diltiazem may be due not only to afterload reduction but also to inhibition of cellular calcium influx. We conclude that 0.3 mg/kg diltiazem and 1.0 mg/kg nitroprusside are beneficial for the treatment of endotoxic shock in newborn rats.

Elevated lead levels in a patient with sickle cell disease and inappropriate secretion of antidiuretic hormone

A five-year-old girl with known sickle cell disease presented with severe hyponatremia and findings compatible with syndrome of inappropriate secretion of antidiuretic hormone (SIADH). She was found to have lead levels in the Class III category. By exclusion, we postulated that the SIADH was in some way related to the high lead levels, since this was the only abnormality the patient exhibited. The toxic lead levels and the elevated vasopressin levels rapidly responded to dimercaprol and calcium EDTA chelation therapy.

Neonatal hypertension. Incidence and risk factors

To determine the incidence and risk factors for neonatal hypertension we studied the entire population of 3179 infants admitted to our neonatal intensive care unit over a 6-year period. We report a 0.81% (26/3179) incidence of hypertension in this population. In 13 patients (50%) the hypertension was renal in origin. In four patients (15.4%), the etiology of hypertension could not be determined. Significant risk factors for neonatal hypertension included: bronchopulmonary dysplasia (5.9% in affected infants v 0.5% in unaffected infants, P less than .001); patent ductus arteriosus (3.07% in affected v 0.5% in unaffected infants, P less than .001); intraventricular hemorrhage (2.89% in affected infants v 0.56% in unaffected infants, P less than .001); and umbilical arterial catheterization (8.8% v 0.2% in infants with and without catheterization, respectively, P less than .001).

Mortality, temporal substrate and insulin responses to endotoxic shock in zero, ten and twenty-eight day old rats

Neonatal sepsis is a significant health problem. However, to our knowledge, the temporal substrates and insulin response to endotoxin have not been characterized in the young animal to guide the investigations of glucoregulation in septic shock in the newborn. We characterized the temporal response to endotoxin in the developing rat. Sprague-Dawley rats were given intraperitoneal Salmonella enteritidis endotoxin in high and low lethal doses to zero, ten and 28 day old rats. Mortality, temporal glucose, lactate, hepatic glycogen and insulin were monitored. Mortality experiments show the ten day old rat is 300 times as sensitive to endotoxin as the 28 day old rat. Plasma glucose concentration increased in the high mortality groups by 120 minutes in the zero and ten day old rats (102 +/- 4 milligrams per deciliter, 119 +/- 6 milligrams per deciliter, respectively, and by 60 minutes in the 28 day old rats (223 +/- 12 milligrams per deciliter). The plasma glucose level decreased to 52 +/- 3 milligrams per deciliter by 240 minutes in the ten day old and by 180 minutes to 99 +/- 8 milligrams per deciliter in the 28 day high mortality groups. Peak lactic acid levels in the high lethality groups were zero day 2.8 +/- 0.2 millimoles per liter in zero day old rats, 3.3 +/- 0.2 millimoles per liter in 28 day old rats. Glycogen in the liver decreased rapidly by 120 minutes in all age groups. Plasma insulin concentration did not elevate significantly in zero and ten day old rats. In the 28 day old rat, insulin concentration increased by 120 minutes to 52 +/- 17 microunits per milliliter. Insulin glucose ratios were also elevated in the 28 day old endotoxin treated rat, indicating hyperinsulinemia. Thus, temporal substrates and insulin responses to endotoxin differ with animal age.

Cord blood thyrotropin screening for congenital hypothyroidism. Three years' experience on the Island of Saint Lucia

Cord blood thyrotropin (TSH) screening for congenital primary hypothyroidism has been in effect on the island of St. Lucia for the past three years. Umbilical cord blood samples are obtained on Guthrie filter paper and then transported 3,000 miles to Loyola University of Chicago and delivered to the Illinois State Metabolic Screening Laboratory. There TSH is measured by radioimmunoassay (RIA). After three years, 1,789 newborns have been screened, and the mean value is 6.23 +/- 0.13 microIU per ml. This mean value is less than previously reported by us in 1986 (10.23 +/- 0.29 microIU per ml).13 It is concluded that this screening service continues to be possible far removed from the population under observation. No case of primary hypothyroidism has been detected. Our decreased mean TSH value is due to the new method currently used by the Illinois State Metabolic Screening Laboratory. Congenital hypothyroidism will not be missed provided internal controls are established and rigidly observed.

Prophylaxis and treatment of newborn endotoxic shock with anti-lipid A monoclonal antibodies

The newborn is very susceptible to gram-negative sepsis/septic shock. The mortality of newborn endotoxic shock continues to be high. Since lipid A is responsible for the toxic effects of lipopolysaccharide, anti-lipid A antibodies may prevent endotoxic shock in the newborn. This study showed that both anti-lipid A monoclonal IgG (A78S1) and anti-lipid A monoclonal IgM (A523) decreased the mortality of endotoxic shock in 10 day old rats. Prophylactic administration of A78S1 and A523 to the pregnant rat decreased the mortality of endotoxic shock in their 0-day-old offspring. Prophylaxis was due to transplacental passage of A78S1 treatment. The mechanism of prophylaxis remains unclear in A523 treatment.

Cepharanthine (biscoclaurine alkaloid) treatment in endotoxic shock of suckling rats

Gram-negative sepsis/septic shock causes significant mortality in newborns. However, there has been no established method for newborn endotoxic shock treatment. Prostaglandins play a role in endotoxic shock. Cepharanthine is a biscoclaurine alkaloid that primarily inhibits phospholipase A2. Therefore, the effects of cepharanthine have been studied on endotoxic shock in newborn rats. Cepharanthine decreased the 24 h mortality of endotoxic shock in a dose-related manner. At the dose of 0.2 mg kg-1 it effectively reduced the mortality from 90 to 21% in newborn rats. It also induced hyperglycaemia in control rats and blunted the hypoglycaemia of endotoxic shock. Cepharanthine did not suppress body weight gain nor did it delay death as seen with glucocorticoid treatment. We conclude that cepharanthine is beneficial in the treatment of newborn endotoxic shock.

A comparison of two common clinical methods with high-pressure liquid chromatography for the measurement of creatinine concentrations in neonates

The accurate measurement of low serum creatinine levels is necessary for estimating clinically useful creatinine clearances in the pediatric population. This study compares two routine clinical methods: the kinetic Jaffé with the newer Kodak enzymatic method against our reference method, high-pressure liquid chromatography, for the measurement of serum and urine creatinine levels in neonates. One hundred and twenty-five serum and 59 urine creatinines and 56 absolute creatinine clearances were measured in neonates ranging from 23 to 46 weeks (mean 32 weeks) post-conceptional age and weighing 480-4398 g (mean 1650 g). Urine creatinine levels, and serum creatinine levels greater than 0.8 mg/dl were equivalent for both clinical methods. However, the enzymatic method was much more accurate (P less than 0.001) than the kinetic Jaffé method for serum creatinine measurements of less than or equal to 0.8 mg/dl. We conclude that the enzymatic methodology is a better clinical choice for the accurate measurement of serum creatinine levels when using these values for the determination of neonatal renal function.

Altered glucose transporter mRNA abundance in a rat model of endotoxic shock

To better understand molecular mechanisms of glucose transport in shock, we studied glucose transporter isoform mRNA abundance after injection of S. enteritidis endotoxin (40 mg/kg) or saline. Six to 8 hours after injection, endotoxin-treated animals compared to controls became hypoglycemic (44 +/- 6 vs. 111 +/- 4 mg/dl) and lactacidemic (5.9 +/- 0.5 vs. 1.3 +/- 0.1). At such times, tissue RNA was isolated and hybridized to Riboprobes for GLUT1 (erythrocyte), GLUT2 (liver), and GLUT4 (muscle/fat) glucose transporter isoforms and expressed as percent of control. GLUT1 mRNA abundance was increased in fat (660%, p less than .05), soleus muscle (314%, p less than .05), and liver (871%, p less than .001) of endotoxin-treated rats. Soleus muscle GLUT4 mRNA levels were increased (+33%, p less than .02), while liver GLUT2 mRNA levels were markedly decreased (-58%, p less than .01). The overall increase in GLUT1 mRNA abundance accompanied by lowered liver GLUT2 mRNA levels may either cause or reflect profoundly altered glucose transport.

Effect of intraosseous saline infusion on hematologic parameters

STUDY OBJECTIVE

To examine the effects of intraosseous saline infusion on hematologic parameters.

DESIGN AND SETTING

Eight New Zealand White rabbits were anesthetized with intramuscular ketamine. An initial blood sample was withdrawn from a earlobe vein on induction of anesthesia. An 18-gauge intraosseous needle was then inserted into the rabbit's proximal tibia, and 10 mL/kg of normal saline was infused over one minute. Two additional blood samples were obtained 15 and 30 minutes after the intraosseous infusion.

MEASUREMENTS

Complete blood counts were performed on the blood samples.

RESULTS

Significant differences were found in monocytes, basophils, and nucleated RBCs from samples drawn before and after intraosseous infusion. The microscopic examination of the peripheral blood smear revealed an increase in the number of burr cells, schistocytes, and polychromasia in the postinfusion samples.

CONCLUSION

We advocate caution in the interpretation of hematologic studies performed on blood samples obtained shortly after an intraosseous infusion.

Enuresis: the difference between night and day

The differentiation between night and day wetting allows the application of practical developmental and behavioral approaches to the diagnosis, evaluation, and therapy of each problem. Wetting the bed is mainly a developmental issue, and wetting the pants is a behavioral one.

Dexamethasone and indomethacin treatment during endotoxicosis in the suckling rat

Gram negative sepsis/septic shock continues to be a major cause of morbidity and mortality in newborns. We studied the effects of anti-inflammatory drugs, indomethacin (IND) and dexamethasone (DX), on glucoregulation, body weight, and mortality in 10-day-old suckling rats administered Salmonella enteritidis lipopolysaccharide (LPS). IND (1.5 mg/kg) or DX (4 mg/kg) was intraperitoneally (ip) administered immediately after highly lethal LPS injection. Both IND and DX attenuated the LPS-induced hypoglycemia and lactacidemia, and decreased the mortality, IND did not alter body weight changes in rats with septic shock. DX continued a catabolic state and reduced their body weights. In rats fasted for 24 hr before LPS injection, DX, but not IND, increased the mortality. We concluded that IND and DX improved the LPS-induced glucose dyshomeostasis and decreased the mortality of endotoxic shock in 4-hr-fasted 10-day-old rats. Per contra, DX was detrimental in 24-hr-fasted 10-day-old endotoxic rats.

Prophylactic immunotherapy in newborn rat endotoxicosis

The incidence and mortality of gram negative sepsis/septic shock remains high in newborns. In this paper, we postulated that prophylactic immunotherapy may be beneficial in newborn endotoxicosis. Lipopolysaccharide (LPS) tolerant rats were produced by serial Salmonella enteritidis LPS injections, and their sera were used for immunotherapy. Antiserum cotreatment blunted hypoglycemia and lactacidemia in S. enteritidis endotoxicosis and decreased the mortality. In 0-day-old rats, antiserum cotreatment groups had a decreased mortality when injected with S. enteritidis LPS (P less than .001), S. typhosa LPS (P less than .005), and Escherichia coli LPS (P less than .05). This global protection suggested that antibody to S. enteritidis LPS could be due to a common LPS antigen. Prophylactic antiserum administration to pregnant rats on the 18th day of gestation decreased the mortality of S. enteritidis endotoxicosis in 0-day-old rats (P less than .001). The prophylactic effects of antiserum was achieved by transplacental passage to the conceptus. We conclude that prophylactic as well simultaneous immunotherapy was beneficial in newborn rat endotoxicosis.

Renal lesions in young rats induced by Salmonella enteritidis endotoxin

Sepsis in newborns and infants is a major pediatric problem often associated with renal dysfunction. The present report deals with changes in renal tissue induced by Salmonella enteritidis endotoxin in 10- and 28-day-old Sprague-Dawley rats. Our studies revealed a 90% lethality within 24 h of 0.1 mg/kg and 35 mg/kg S. enteritidis endotoxin injection in 10- and 28-day-old rats, respectively. The 10- and 28-day-old animals received a single intraperitoneal injection of the 90% lethality dose and were sacrificed at different intervals for histopathological evaluation of kidneys by light and electron microscopy. The glomeruli showed visceral epithelial and endothelial cell swelling and polymorphonuclear leukocyte and platelet accumulation in the capillary lumina. Cortical and medullary tubules showed edematous separation, mild focal epithelial cell damage and focal intertubular hemorrhage. Renal sections of 28-day-old experimental rats showed increased numbers of polymorphs in the glomerulus and enlarged mesangial matrix. These sections also showed an increase in the number of hemorrhagic foci in 10 x field compared with the 10-day-old experimental rats. Endothelial cells of renal vasculature showed cytoplasmic swelling, vacuolization, autophagic vesicle formation and presence of secondary lysosomes. Changes in the endothelial cells of peritubular microvasculature were extensive, resulting in focal degeneration and partial loss of endothelial lining. These studies show that infant rats are extremely sensitive to S. enteritidis endotoxin requiring 1/350 the dose given to young adults to induce histopathological changes in kidney; the endothelial cells of microvasculature appear to be the primary targets of endotoxic injury irrespective of age.

Glucagon in the acute management of ureteral colic

Use of intravenous glucagon should be considered in all patients with urinary calculi who fail to respond to narcotic analgesia and hydration. The lack of adverse side effects and the potential to reduce the morbidity associated with surgical intervention make glucagon a valuable adjunct in medical management of ureteral colic.

Endotoxin in newborn septic shock: significance, metabolic, and cardiovascular changes

The role of endotoxin in newborn septic shock is reviewed. Metabolic and cardiovascular changes, as known to us, are described with special emphasis that the newborn is not a "small adult." Developmental or maturational changes are hypothesized to be the major cause of these differences between age groups. Finally, it is our belief that newborn septic shock is an important topic for further investigation.

Concurrent clinical and metabolic derangements in the newborn rat: a late phase sepsis model

Gram negative sepsis is a leading cause of human newborn morbidity and mortality. The clinical signs and glucose and lactate concentration during the late phase of newborn rat endotoxicosis has not been well characterized. In order to define a late phase model of sepsis, simultaneous clinical signs (loss of response to pain [RP] and/or righting reflex [RR]), and metabolic (glucose, lactate) concentrations were studied in the 10 day old Sprague-Dawley rat. The rats were fasted for four hours and then injected with either saline (control) or 0.1 mg per kg Salmonella enteritidis (LD90 @ 24) endotoxin intraperitoneally. Rats were then examined every 15 minutes beginning two hours post injection for the presence or absence of loss of RR and/or loss of RP. Central blood samples were collected for determination of glucose and lactate at the moment of loss of the predetermined clinical parameter. Metabolic parameters were also determined on saline treated controls time matched to the experimental groups. Rats were grouped as follows: GrI, (n = 10), saline three hours post injection; GrIII, (n = 10), saline five hours post injection; GrII, (n = 45), endotoxin at the moment of loss of RR; GrVI, (n = 14), endotoxin at 8.5 hrs post injection (termination of experiment, all with loss of RR); GrIV, (n = 11) endotoxin at loss of RP; and GrV, (n = 10) saline at 8.5 hr post injection.(ABSTRACT TRUNCATED AT 250 WORDS)

Myocardial infarction with normal results of coronary angiography following diltiazem withdrawal

Abrupt withdrawal of calcium channel blocking agents has been associated with symptoms of ischemic heart disease, but acute myocardial infarction has not been noted. Herein is described a severely uremic patient who had an acute myocardial infarction shortly after discontinuance of diltiazem, although results of subsequent coronary arteriography were normal. It is postulated that myocardial damage occurred because of increased intracellular calcium flux, augmented myocardial contractility, and/or drug withdrawal-related coronary spasm.

Hypertension, mineralocorticoid-resistant hyperkalemia, and hyperchloremic acidosis in an infant with obstructive uropathy

An 8-week-old infant with hypertension, hyperkalemia, and hyperchloremic acidosis, presumably due to chloride shunt type of distal renal tubular acidosis, is described. The patient's renin-aldosterone axis was intact. The infant was also found to have an obstructed solitary kidney. Despite correction of the obstruction and improvement in the glomerular filtration rate accompanied by normal development, hyperkalemia and renal tubular acidosis persisted. The defect was still demonstrable 9 months following relief of the obstruction. We conclude that neonatal obstructive uropathy can result in renal tubular acidosis of the chloride shunt type. The reversibility of this defect is, as yet, unknown.

Systemic lupus erythematosus presenting with hyporeninemic hypoaldosteronism in a 10-year-old girl

Hyperkalemia has been noted to occur spontaneously in patients with long-standing systemic lupus erythematosus who did not have advanced renal insufficiency. The patients previously described all had relatively normal renin-aldosterone systems, and the hyperkalemia was thus presumed to be secondary to a primary defect in renal tubular potassium secretion. We describe at 10-year-old girl with lupus nephritis, without significant renal insufficiency, who had hyperkalemia from hyporeninemic hypoaldosteronism postulated to be due to vasculitis involving the afferent/efferent arterioles and juxtaglomerular apparatus.

Fast hemoglobins and red blood cell metabolites in citrate phosphate dextrose adenine stored blood

Blood was drawn from 10 fasted, healthy volunteers and stored under standard blood bank conditions in citrate-phosphate-dextrose-adenine (CPDA-1). Blood was sampled before storage (Day 0) and on Days 5, 12, 19, 26, and 35. Laboratory testing for glucose, HbAla + b, HbAlc, pyruvic acid, lactic acid, adenosine triphosphate (ATP), 2, 3-diphosphoglycerate (2,3DPG), plasma free hemoglobin (Hb) and pH (blood gases) were performed. In addition, P50 was also serially measured in two of the individuals and in their stored blood. Significant elevations of HbAla + b and HbAlc (fast hemoglobins) were found on Days 12 and 19 of storage (p less than 0.05). These elevations of fast hemoglobins are due to hypoxia, acidosis, and hyperglycemia. Following the initial elevation of the fast hemoglobins (Hbs), there was a decline in their concentration, from Day 12, which could partly be explained by cell death.

Accidental carbon monoxide poisoning

In this case report of an accidental automobile carbon monoxide poisoning, we identify the following risk factors: freezing temperature, young passenger age, location in the rear of the auto, smaller patient mass, and auto disrepair. The pathogenesis of carbon monoxide poisoning is reviewed. Emergency treatment and suggested criteria for hyperbaric oxygen use in pediatric patients are discussed.

Anaphylaxis during hemodialysis

A ten year old boy with renal failure secondary to the branchio-oto-renal syndrome had a severe anaphylactic reaction during his first hemodialysis. The allergen implicated in the reaction was ethylene oxide gas used for dialyzer sterilization. RAST testing done just after anaphylaxis may be falsely negative and thereby misleading.