mTOR: a placental growth signaling sensor

The proliferation and differentiation of trophoblast cells is under the control of a variety of hormones and growth factors and is influenced by nutrient availability. The intracellular signaling pathways acting downstream of these mitogenic factors and nutrients to regulate trophoblast proliferation and placental development are poorly understood. Immortalized human trophoblast cells were used (HTR-8/SVneo) to investigate trophoblast proliferation in response to angiopoietin-2 (Ang-2), a major angiogenic factor and glucose (a major nutrient). Trophoblast cell proliferation was induced through activation of the phosphatidylinositol-3 (PI-3) kinase and the mammalian target of rapamycin (mTOR) signaling pathways, following Tie-2 receptor activation. Glucose also stimulated trophoblast cell proliferation through mTOR signaling. Ang-2 activated mTOR via PI-3 kinase-dependent signaling; whereas glucose-mediated mTOR activation was PI-3 kinase-independent and involved a novel nutrient sensor, glutamine fructose-6-phosphate amidotransferase (GFAT). Metabolites of the GFAT reaction acted upstream of mTOR and functioned as a nutrient sensor to regulate trophoblast cell proliferation in response to glucose. Overall, the results show that growth factor and nutrient signaling converge at tuberin, an upstream regulator of mTOR and that mTOR functions as an important placental growth signaling sensor. These results are the first to link mTOR with GFAT metabolites as nutrient sensors for trophoblast cell proliferation.

Phenotypic features of myoclonus-dystonia in three kindreds

BACKGROUND

Myoclonus-dystonia (M-D) is a movement disorder with involuntary jerks and dystonic contractions. Autosomal dominant alcohol-responsive M-D is associated with mutations in the epsilon-sarcoglycan gene (SGCE) (six families) and with a missense change in the D2 dopamine receptor (DRD2)gene (one family).

OBJECTIVE

To investigate the clinical phenotype associated with M-D including motor symptoms, psychiatric disorders, and neuropsychological deficits.

METHODS

Fifty individuals in three M-D families were evaluated and a standardized neurologic examination and DNA analysis were performed. Psychiatric profiles were established with the Diagnostic Interviews for Genetic Studies (DIGS) and the Yale-Brown Obsessive-Compulsive Scale (YBOCS). Cognition was evaluated with standardized neuropsychological tests.

RESULTS

Distinct truncating mutations in the SGCE gene were identified in each family. Additionally, a missense alteration in the DRD2 gene was previously found in one family. Motor expression was variable, with onset of myoclonus or dystonia or both affecting the upper body and progression to myoclonus and dystonia in most cases. Psychiatric profiles revealed depression, obsessive-compulsive disorder, substance abuse, anxiety/panic/phobic disorders, and psychosis in two families, and depression only in the third family. Averaged scores from cognitive testing showed impaired verbal learning and memory in one family, impaired memory in the second family, and no cognitive deficits in the third family.

CONCLUSIONS

Cognitive deficits may be associated with M-D. Psychiatric abnormalities correlate with the motor symptoms in affected individuals. Assessment of additional M-D families with known mutations is needed to determine whether these are characteristic phenotypic manifestations of M-D.

Hypoxia in vivo decreases peroxisome proliferator-activated receptor alpha-regulated gene expression in rat heart

We tested the hypothesis that hypoxia decreases PPARalpha-regulated gene expression in heart muscle in vivo. In two rat models of systemic hypoxia (cobalt chloride treatment and iso-volemic hemodilution), transcript levels of PPARalpha and PPARalpha-regulated genes (pyruvate dehydrogenase kinase 4 (PDK4), muscle carnitine palmitoyltransferase-I (mCPT-I), and malonyl-CoA decarboxylase (MCD)) were measured using real-time quantitative RT-PCR. Data were normalized to the housekeeping gene beta-actin. Atrial natriuretic factor (ANF) and pyruvate dehydrogenase kinase 2 (PDK2), which are not regulated by PPARalpha, served as controls. CoCl(2) treatment decreased PPARalpha, PDK4, mCPT-I, and MCD mRNA levels. Iso-volemic anemia also caused a significant decrease in PPARalpha, PDK4, and MCD mRNA levels. Transcript levels of mCPT-I showed a slight, but not significant decrease (P = 0.08). Gene expression of beta-actin, ANF, and PDK2 did not change with either CoCl(2) treatment nor with anemia. Myocardial PPARalpha-regulated gene expression is decreased in two models of hypoxia in vivo. These results suggest a transcriptional mechanism for decreased fatty oxidation and increased reliance of the heart for glucose during hypoxia.

Kinetic spectrophotometric method for the determination of oxalic acid by its catalytic effect on the oxidation of safranine by dichromate

A new catalytic kinetic spectrophotometric method for the determination of oxalic acid has been described based on its catalytic effect on the redox reaction between safranine and dichromate in dilute sulfuric acid media. The reaction is monitored photometrically by measuring the decrease in absorbance of safranine at the maximum wavelength of 530 nm. Under the optimum conditions, a calibration graph from 0.10 to 10.00 microg ml(-1) of oxalic acid with a detection limit of 0.08 microg ml(-1) was obtained. The relative standard deviation (R.S.D.) for ten replicate measurements of 1.0 and 5.0 microg ml(-1) oxalic acid was 2.7 and 2.5%, respectively. The purposed method is simple, sensitive, selective and inexpensive. The applicability of the proposed method was determined by the determination of oxalic acid in spinach and wastewater samples with satisfactory results.

Differential pulse adsorption stripping voltammetric determination of copper(II) with 2-mercaptobenzimidazol at a hanging mercury-drop electrode

Copper(II) was selectively accumulated on a hanging mercury-drop electrode by using 2-mercaptobenzimidazole. Ensuing measurements were carried out by differential pulse adsorption stripping voltammetry. Factors affecting the accumulation, reduction, and stripping steps were investigated and a procedure was developed. The optimum conditions for the analysis of copper were pH 5.0, 5.33 x 10(-5) M 2-mercaptobenzimidazole and an accumulation potential of -0.10 V (vs. Av/AgCl). A linear range was obtained in the concentration range 0.2-100 ng/ml with a 90 s accumulation time and a scan rate of 16 mV/s. For ten successive determinations of 1.0, 20.0 and 70.0 ng/ml copper(II), relative standard deviations of 4.2, 3.5 and 2.8%, respectively, were obtained. The developed method was applied to the determination of copper in commercial salts and aluminium alloys.

Prolonged fetal ritodrine exposure and immediate neonatal outcome

Ritodrine hydrochloride was administered over a period of two years to a total of 200 women in premature labor. One hundred sixty-two (81 per cent) of the women carried pregnancy to 35 weeks or longer. To determine the effect of ritodrine on the neonates, the duration and amount of exposure, onset of exposure, and interval between cessation of exposure and delivery were correlated with gestational age, birth weight, Apgar scores, mortality, and the presence of hypoglycemia, hyperbilirubinemia, respiratory distress, and intrauterine growth retardation. Infants exposed for six weeks or more (long-term exposure) were significantly heavier than those exposed for shorter periods (short-term exposure), a difference that was possibly attributable to differences in gestational age at birth. Infants who were exposed as fetuses to ritodrine beginning at 30 weeks' or less gestation needed phototherapy more often than did infants whose fetal exposure began at after 30 weeks' gestation. Neither duration of exposure nor gestational age at birth was a significant factor in hyperbilirubinemia. Of infants delivered at or after 35 weeks' gestation, 32 (20 per cent) experienced early hypoglycemia; and 26 of these (81 per cent) were exposed up to the day of delivery. This outcome differed significantly from that of infants whose exposure stopped at least one week before delivery. In addition, respiratory distress syndrome was more common in those infants exposed up until delivery (34 of 36).(ABSTRACT TRUNCATED AT 250 WORDS)

Affine-similar shape retrieval: application to multiview 3-D object recognition

The feasibility of representing a three-dimensional (3-D) object with a small number of standard views is studied. The object boundary of each view is considered as a two dimensional (2-D) shape and is represented by the locations of the maxima of its curvature scale space (CSS) image contours. The idea is to identify an unknown object from an image taken from a random view by using the stored descriptions of the standard views. The CSS image has been selected for MPEG-7 standardization. The maxima of CSS image have already been used to represent 2-D shapes in different applications under similarity transforms. Since the new application involves affine transforms, we first examine the effects of general affine transforms on the representation and show that the locations of the maxima of the CSS image do not move dramatically even under large affine transformations. Our system for shape-based retrieval from large image databases is then applied to multiview 3-D object representation and recognition. Our collection of 3-D objects consists of 18 aircraft of different shapes. Three silhouette contours corresponding to random views are separately used as input for each object. Results indicate that robust and efficient 3-D free-form object recognition through multiview representation can be achieved using the CSS representation.

Effects of early inhaled beclomethasone therapy on tracheal aspirate inflammatory mediators IL-8 and IL-1ra in ventilated preterm infants at risk for bronchopulmonary dysplasia

We tested the hypothesis that inhaled beclomethasone therapy for prevention of bronchopulmonary dysplasia (BPD) reduces pulmonary inflammation. As part of a randomized, placebo-controlled trial, interleukin-8 (IL-8) and interleukin-1 receptor antagonist (IL-1ra) concentrations in tracheal aspirates were measured as markers of pulmonary inflammation. On study days 1 (baseline), 8, 15, and day 28 of age, samples were obtained from enrolled infants (birth weights <1,251 g, gestational age <33 week, 3 to 14 days of age) who remained ventilated and had not received systemic glucocorticoid therapy. Cytokine levels (pg/microg of free secretory component of immunoglobulin A) were compared between groups. We determined whether baseline cytokine levels modified treatment effect regarding subsequent need for systemic glucocorticoid therapy or occurrence of BPD (age 28 days). Tracheal aspirates were obtained from 161 infants (77 receiving beclomethasone, 84 receiving placebo). Median IL-8 levels were lower in beclomethasone versus placebo infants on study days 8 (82.9 vs. 209.2, P < 0.01) and 15 (37.4 vs. 77.4, P < 0.03) after controlling for antenatal glucocorticoid therapy and maternal race. Median IL-1ra levels were lower in beclomethasone versus placebo infants only on study day 8 (86.5 vs. 153.3, P < 0.01). Fewer beclomethasone infants with baseline IL-8 levels in the interquartile range required systemic glucocorticoid therapy (beclomethasone 30.6% vs. placebo 65.8%, P < 0.01) or developed BPD (beclomethasone 42.4% vs. placebo 69.4%, P < 0.03). We conclude that early-inhaled beclomethasone therapy was associated with a reduction in pulmonary inflammation after 1 week of therapy. Beclomethasone-treated infants with moderately elevated baseline IL-8 levels received less subsequent systemic glucocorticoid therapy and had a lower incidence of BPD than nontreated infants.

Effect of single versus multiple courses of antenatal corticosteroids on maternal and neonatal outcome

OBJECTIVE

Treatment of pregnant mothers with a single course of antenatal corticosteroids significantly reduces neonatal mortality and morbidity. Multiple weekly courses are often given. However, the safety and efficacy of repeated courses of antenatal corticosteroids have not been adequately studied.

STUDY DESIGN

A retrospective study was performed for 609 mothers and their 713 infants who were treated with 1 to 12 courses of antenatal corticosteroids. Data for 369 singleton preterm infants born at < or =34 weeks' gestation, 210 multiple gestations, and 134 infants delivered at > or =35 weeks' gestation were analyzed separately.

RESULTS

The incidence of respiratory distress syndrome was 45% for single-course and 35% for multiple-course groups (P =.005; odds ratio, 0.44; 95% confidence interval, 0.25-0.79). The multiple-course group also had significantly less patent ductus arteriosus (20% vs 13%; P =.016). Incidence of death before discharge and other neonatal morbidities were similar. The multiple-course group had a reduction of 0.46 +/- 0.19 cm in head circumference at birth (P =.013) when adjusted for gestational age and preeclampsia. The 2 groups had similar birth weights. Infants born at > or =35 weeks' gestation, multiple-gestation infants, and infants who were born >7 days after the last corticosteroid dose had similar outcomes, regardless of the number of courses they received. Mothers treated with multiple courses compared with a single course had a significantly higher incidence of postpartum endometritis (P =.013), even though they had a lower incidence of prolonged rupture of membranes (24% vs 33%, P =.06) and similar cesarean delivery rates.

CONCLUSION

Exposure to multiple courses of antenatal corticosteroids compared with a single course resulted in a significant reduction in the incidence of respiratory distress syndrome in singleton preterm infants delivered within a week of the last corticosteroid dose. This was associated with a reduction in birth head circumference and an increased incidence of maternal endometritis. Whether the potential benefits of repeated therapy clearly outweigh the risks will ultimately be determined in randomized prospective controlled trials.

Pulmonary function and electrolyte balance following spironolactone treatment in preterm infants with chronic lung disease: a double-blind, placebo-controlled, randomized trial

OBJECTIVE

To study the effect of spironolactone on dietary electrolyte supplementation, pulmonary function, and electrolyte balance in premature infants with chronic lung disease.

STUDY DESIGN

A double-blind, randomized, and placebo-controlled trial was designed to study two groups of low birth weight infants with chronic lung disease at Pennsylvania Hospital. The placebo group received chlorothiazide and a placebo, and the spironolactone group received chlorothiazide and spironolactone during the 2-week study period. A two-tailed t-test was used to determine equivalence between the two groups.

RESULTS

Pulmonary compliance, resistance and tidal volume, serum sodium and potassium, and FIO2, were not statistically different between the two groups. The need for sodium and/or potassium chloride did not differ between the two groups, nor did the quantity of each salt.

CONCLUSION

The addition of spironolactone did not reduce the requirement for supplemental electrolytes, nor did it improve pulmonary mechanics or electrolyte balance.

Aspergillosis in children with cancer: A 34-year experience

A retrospective review of medical records, microbiology and pathology laboratory records, and nosocomial infection surveillance data was undertaken to describe the experience with culture-documented aspergillus infection in pediatric cancer patients at our facility. Sixty-six patients were identified from a 34-year period. The most common underlying diagnosis was leukemia. Risk factors included neutropenia, immunosuppression, and prior antibiotic therapy. On the basis of clinical presentation, 23 patients were believed to have disseminated disease and 43 to have localized disease. The lung was the most frequently affected organ. Despite aggressive medical and surgical management, overall mortality was 85% within the first year after diagnosis. Patients who presented with disease in sites other than the lungs fared better than patients with initial pulmonary involvement (P=.0014). Aspergillosis continues to be associated with poor outcome. Development of improved medical and adjuvant therapies, including surgery, is warranted.

Clinical scoring system: a valuable tool for decision making in cases of acute appendicitis

OBJECTIVE

Decision making in cases of acute appendicitis poses a clinical challenge specially in developing countries where advanced radiological investigations do not appear cost effective and so clinical parameters remain the mainstay of diagnosis. The aim of our study was to devise a scoring system from our local database and test its accuracy in the preoperative diagnosis of acute appendicitis.

METHODS

Clinical data from 401 patients having undergone appendectomy were collected to identify predictive factors that distinguished those with appendicitis from those who had a negative appendectomy. Ten such factors were identified and using Bayesian probability a weight was assigned to each and the results summated to get an overall score. A cut-off point was identified to separate patients for surgery and those for observation. The scoring system was then retrospectively applied to a second population of 99 patients in order to compare suggested actions (derived from the scoring system) to those actually taken by surgeons. The sensitivity, specificity and accuracy for the level of decision was then calculated.

RESULTS

Of the 99 patients, the method suggested immediate surgery for 65 patients, 63 of whom had acute appendicitis (3.1% diagnostic error rate). Of the 33 patients in whom the score suggested active observation, 18 had appendicitis. The accuracy of our scoring system was 82%. The method had a sensitivity of 78%, specificity 89% and a positive predictive value of 97%. The negative appendectomy rate determined by our study was 7% and the perforation rate 13%.

CONCLUSION

Scoring system developed from a local database can work effectively in routine practice as an adjunct to surgical decision making in questionable cases of appendicitis.

Adrenal function in premature infants during inhaled beclomethasone therapy

OBJECTIVE

We tested the hypothesis that inhaled beclomethasone therapy for prevention of bronchopulmonary dysplasia does not cause adrenal suppression.

STUDY DESIGN

Infants receiving ventilatory support with birth weights </=1250 g and born at <33 weeks' gestation, age 3 to 14 days, were enrolled in a multicenter randomized trial to study the efficacy and safety of beclomethasone therapy versus placebo for prevention of bronchopulmonary dysplasia. Adrenal function was assessed on study day 21 (+/- 2 days) by determination of basal and stimulated plasma cortisol levels. Initially, cortisol response was assessed with insulin-induced hypoglycemia test (IIHT) (n = 63) until an interim analysis revealed insignificant cortisol response in both study groups. Thereafter, cosyntropin stimulation was used (n = 85).

RESULTS

Beclomethasone therapy was associated with lower median basal cortisol levels (5 microg/dL beclomethasone, 6 microg/dL placebo, P =.04). IIHT revealed insignificant change in cortisol response within each group. Cortisol response to cosyntropin stimulation was similar for each group (17 microg/dL beclomethasone, 18 microg/dL placebo, P =.86).

CONCLUSION

Beclomethasone therapy was associated with a small decrease in basal cortisol levels. There was no evidence of adrenal suppression in response to cosyntropin stimulation during beclomethasone therapy. Lack of cortisol response to hypoglycemia may reflect missed timing and/or decreased response of the premature infants' hypothalamic-pituitary-adrenal axis to hypoglycemia.

Early inhaled glucocorticoid therapy to prevent bronchopulmonary dysplasia

BACKGROUND

The safety and efficacy of inhaled glucocorticoid therapy for asthma stimulated its use in infants to prevent bronchopulmonary dysplasia. We tested the hypothesis that early therapy with inhaled glucocorticoids would decrease the frequency of bronchopulmonary dysplasia in premature infants.

METHODS

We conducted a randomized, multicenter trial of inhaled beclomethasone or placebo in 253 infants, 3 to 14 days old, born before 33 weeks of gestation and weighing 1250 g or less at birth, who required ventilation therapy. Beclomethasone was delivered in a decreasing dosage, from 40 to 5 microg per kilogram of body weight per day, for four weeks. The primary outcome measure was bronchopulmonary dysplasia at 28 days of age. Secondary outcomes included bronchopulmonary dysplasia at 36 weeks of postmenstrual age, the need for systemic glucocorticoid therapy, the need for bronchodilator therapy, the duration of respiratory support, and death.

RESULTS

One hundred twenty-three infants received beclomethasone, and 130 received placebo. The frequency of bronchopulmonary dysplasia was similar in the two groups: 43 percent in the beclomethasone group and 45 percent in the placebo group at 28 days of age, and 18 percent in the beclomethasone group and 20 percent in the placebo group at 36 weeks of postmenstrual age. At 28 days of age, fewer infants in the beclomethasone group than in the placebo group were receiving systemic glucocorticoid therapy (relative risk, 0.6; 95 percent confidence interval, 0.4 to 1.0) and mechanical ventilation (relative risk, 0.8; 95 percent confidence interval, 0.6 to 1.0).

CONCLUSIONS

Early beclomethasone therapy did not prevent bronchopulmonary dysplasia but was associated with lower rates of use of systemic glucocorticoid therapy and mechanical ventilation.

Regional hemodynamic effects of dopamine in the sick preterm neonate

OBJECTIVE

To study the effects of dopamine on renal, mesenteric, and cerebral blood flow in sick preterm neonates.

STUDY DESIGN

The pulsatility index was used to assess the dopamine-induced changes in renal, mesenteric, and cerebral blood flow by means of color Doppler ultrasonography in 23 nonhypotensive preterm neonates (birth weight: 981 +/- 314 g; postnatal age: <2 days). Dopamine was given at a dose of 6.1 +/- 3.0 microgram/kg per minute to combat oliguria, impaired peripheral perfusion, or both. Blood flow velocity measurements were made before and during dopamine administration, with each patient serving as his or her own control subject.

RESULTS

Dopamine significantly increased blood pressure and urine output. Dopamine decreased the pulsatility index in the renal artery (2.98 +/- 1.18 vs 1.68 +/- 0.45; P <.05) while the pulsatility index in the superior mesenteric and medial cerebral artery was not affected. Thus renal blood flow increased while mesenteric and cerebral blood flow remained unchanged during dopamine treatment. The increase in renal blood flow was independent of the blood pressure changes.

CONCLUSIONS

These findings suggest a functionally mature renal, but not mesenteric, vasodilatory dopaminergic response in the preterm neonate. The observations also indicate the lack of an effect of low- to medium-dose dopamine on cerebral hemodynamics in the nonhypotensive preterm neonate.

Respiratory and systemic effects of inhaled dexamethasone on ventilator dependant preterm infants at risk for bronchopulmonary dysplasia

Short-term inhaled dexamethasone therapy was evaluated in a double blind placebo controlled trial in 36 ventilator dependent preterm neonates (BW < 1500 gm, postnatal age > 7 days) who were at risk for bronchopulmonary dysplasia. Pulmonary and systemic effects were compared at early (day 3), late (7-10 days) and post (14 days after initiation) phases of therapy. Airflow mechanics improved as demonstrated by a net 101% improvement in pulmonary resistance (a decrease from 139 to 101 cm H2O/L/s in the dexamethasone treated infants as compared to an increase from 153 to 267 cmH2O/L/s in the placebo treated infants during the early phase of therapy); this was associated with a 45% increase in inspiratory airflow (1.29 +/- 0.43 to 1.87 +/- 0.978 L/min; p < 0.01), and 37% increase in expiratory airflow. These changes resulted in a significant reduction in the work of breathing such that the mean tidal driving pressure significantly decreased from 13.6 cmH2O to 9.4 cm H2O with inhaled steroid administration. Though the brief duration of therapy did not result in cessation of ventilatory support, the level of support was significantly reduced (decreased values of oxygen supplementation, mean airway pressure and oxygenation index and increased ventilatory efficiency index). The inhaled dexamethasone therapy was also associated with systemic absorption of the drug as evidenced by transient but apparently reversible reduction in serum cortisol levels. No systemic side effects of hypertension, hyperglycemia or nosocomial sepsis were observed. These data demonstrate beneficial effects of short-term inhaled dexamethasone on the resistive airflow properties of preterm infants at risk for BPD and may provide adjunctive means to facilitate weaning in the ventilator dependent neonates.

Serious infections due to penicillin-resistant Streptococcus peneumoniae in two children with nephrotic syndrome

Children with nephrotic syndrome are susceptible to the development of invasive bacterial infections, particularly those caused by Streptococcus peneumoniae. Recently, penicillin-resistant pneumococcal infections in children have occurred in increased frequency in some regions. We have seen two children with nephrotic syndrome who developed penicillin-resistant pneumococcal bacteremia and/or peritonitis. A change in the initial therapy from penicillin in the usual dose in these patients must be considered.

The HA1 of cold-adapted influenza B vaccine is not altered during replication in human vaccinees

Influenza viruses recovered from 14 children 2-10 days after vaccination with an egg-grown, cold-adapted influenza B vaccine (B/AA/1/86) were analyzed. Hemagglutination-inhibition (HI) assays using monoclonal antibodies did not detect antigenic differences between the vaccine strain and the viruses recovered from the vaccinees. Furthermore, nucleotide sequence analysis of the HA1 region did not reveal any changes compared to the sequence of the vaccine strain. These findings indicate that influenza B vaccine hemagglutinin is genetically stable during replication in human vaccinees.

Penicillin- and cephalosporin-resistant strains of Streptococcus pneumoniae causing sepsis and meningitis in children with sickle cell disease

OBJECTIVE

We investigated the possibility that antimicrobial-resistant pneumococci were causing invasive disease in children with sickle-cell disease (SCD).

STUDY DESIGN

Records of all children with SCD observed at the Mid-South Sickle Cell Center (MSSCC) at LeBonheur Children's Medical Center were reviewed from January 1990 to June 1994. Children with SCD and pneumococcal sepsis were identified. The Streptococcus pneumoniae isolates from these children were examined for serotype and antimicrobial susceptibilities. Two additional children not observed in the MSSCC had pneumococcal sepsis caused by penicillin-resistant isolates and were also included.

RESULTS

Antimicrobial susceptibility testing of the six penicillin-resistant isolates revealed that four were resistant to trimethoprim-sulfamethoxazole, two to erythromycin, and one to clindamycin. The two isolates that were resistant to ceftriaxone also were multiply resistant. From the MSSCC, 26 children had pneumococcal sepsis during the 4 1/2-year period studied. Five of these children (19%) died. Four (15%), including one who died, were infected with penicillin-resistant strains.

CONCLUSION

Pneumococcal sepsis, meningitis, and infections of other foci in children with SCD may be caused by S. pneumoniae that is resistant to one or more antimicrobial agents, including penicillin. The addition of vancomycin to the antibiotics currently used for initial management should be considered in areas where the antibiotic resistance of S. pneumoniae is prevalent.

Severe retinopathy of prematurity in infants with birth weights less than 1250 grams: incidence and outcome of treatment with pharmacologic serum levels of vitamin E in addition to cryotherapy from 1985 to 1991

OBJECTIVE

To determine the effect of vitamin E prophylaxis and treatment on the sequelae of severe (threshold) retinopathy of prematurity (ROP) in infants treated with cryotherapy at Pennsylvania Hospital from 1985 to 1991.

STUDY DESIGN

Beginning on day 0, all infants with birth weights < or = 1250 gm received supplements of vitamin E using standard preparations. Serum E levels of 23 to 58 mumol/L (1 to 2.5 mg/dl) were targeted for infants with immature retinal vasculature or ROP of stage 2 or less in severity, and levels of 58 to 81 mumol/L (2.5 to 3.5 mg/dl) for infants with prethreshold ROP. At diagnosis of threshold ROP, treatment with a parenteral investigational new drug preparation of alpha-tocopherol was begun to raise serum levels to the pharmacologic range (93 to 116 mumol/L or 4 to 5 mg/dl). Within 3 days of diagnosis, and at the discretion of the retinal specialist, one or both eyes were treated with cryotherapy. Visual outcome at 4 years was compared with the 42-month outcome reported for eyes in the infants randomly assigned to treatment in the 1986-1987 Multicenter Trial of Cryotherapy for ROP (CRYO-ROP).

RESULTS

Threshold ROP developed in 22 of 450 surviving infants (age 3 months). All were treated with pharmacologic serum levels of vitamin E; 17 infants were also treated with cryotherapy (10 in one eye and 7 in both eyes). These 17 infants, in comparison with infants in the CRYO-ROP trial (n = 187), were at least at equal risk for poor visual outcome on the basis of birth weight, gestational age, the percentage of zone 1 ROP, and mean interval from appearance of ROP to diagnosis of prethreshold ROP, which was shorter at Pennsylvania Hospital (4.1 days for the Pennsylvania Hospital group, 10.3 days for the CRYO-ROP group). However, on the basis of the mean number of days from diagnosis of prethreshold to threshold ROP (12.5 days for Pennsylvania Hospital, 10.5 days for CRYO-ROP) and the extent of extraretinal neovascularization at threshold (mean 7.9 sectors for Pennsylvania Hospital, 9.7 for CRYO-ROP), progression of retinopathy beyond the prethreshold stage had slowed and visual outcome in the eyes of infants at Pennsylvania Hospital treated with both cryotherapy and vitamin E (worse eye used for those treated with bilateral cryotherapy) was better than that reported for the treated eye of infants in the CRYO-ROP group (percentage of favorable visual acuity, 76% vs 48%, p = 0.04; percentage of normal structure posterior retinal pole, 71% vs 38%, p < or = 0.02).

CONCLUSIONS

In this small case series, the combination of cryotherapy with anti-oxidant prophylaxis and treatment appeared to decrease the severity and sequelae of threshold ROP. This hypothesis deserves testing in a large, randomized clinical trial.