Hypoxic-ischemic encephalopathy with cystic brain stem necroses and thalamic calcifications in a preterm twin.

A severe and rare ischemic brain lesion in a preterm twin boy is reported. The boy was born after two weeks of anhydramnios and amnionic infection at 24 weeks of gestation. Following a difficult Caesarean section and prolonged umbilical cord compression he developed prenatal acidosis with an umbilical cord pH of 6.96. At the age of 7 h, heart rate variability narrowed due to severely disturbed brain stem function and the patient developed clinical signs of hypoxic-ischemic encephalopathy. Sonography demonstrated extensive symmetrical brain stem and basal ganglia lesions. After a prolonged comatose and apneic state, death occurred at the age of 25 days. Autopsy confirmed columnar bilateral cavitation of basal ganglia, diencephalon, brain stem and spinal gray matter, as well as focal calcifications in the palladium, thalamus, and brain stem. The findings highly resemble those observed after experimental or clinical cardiac arrest.

Nitroglycerin application during cesarean delivery: plasma levels, fetal/maternal ratio of nitroglycerin, and effects in newborns.

OBJECTIVE: We sought to investigate maternal and fetal nitroglycerin metabolization and to assess the clinical condition of neonates after intravenous nitroglycerin application during cesarean delivery. STUDY DESIGN: At the time of the uterine puncture incision, either 0. 25 mg or 0.5 mg nitroglycerin or a physiologic sodium chloride solution was administered as an intravenous bolus. Plasma concentrations of nitroglycerin and its metabolites were measured in maternal venous blood and in umbilical blood samples taken immediately after cord clamping. Arterial blood pressure, pulse rates, and Apgar scores were recorded for the neonates 1, 5, and 10 minutes after birth. RESULTS: Sixty-two patients were included in the pharmacokinetic study. Median maternal plasma levels 1 and 5 minutes after injection of 0.5 mg nitroglycerin were 80 and 3.2 ng/mL, respectively; median maternal plasma levels 1 and 5 minutes after injection of 0.25 mg nitroglycerin were 38 and 1.2 ng/mL, respectively. In the umbilical vein 1 minute after application of 0. 5 mg or 0.25 mg nitroglycerin, the plasma levels were 0.41 and 0.09 ng/mL, respectively, and in the umbilical artery they were 0.03 and 0.008 ng/mL, respectively. Circulatory parameters and Apgar scores in the neonates did not differ significantly from those found in the placebo group. CONCLUSION: The level of nitroglycerin in umbilical plasma was two to three orders of magnitude lower than that found in maternal plasma and clearly in a subtherapeutic range. There was no indication that prenatal application of nitroglycerin to facilitate obstetric management is hazardous for neonates.

Changing practices of red blood cell transfusions in infants with birth weights less than 1000 g.

OBJECTIVE: Extremely low birth weight (ELBW) infants frequently undergo transfusion because they are critically ill, often need artificial ventilation, and have the highest blood sampling loss in relation to their weight. During the last decade our transfusion guidelines were changed 3 times to become more restrictive. We hypothesized that these modifications substantially decreased the number of transfusions in our ELBW infants. METHODS: We performed a single-center analysis of 256 infants with birth weights from 500 to 999 g who were admitted from 1989 to 1997 and included 3 study periods, each starting with newly modified transfusion guidelines in April 1989, September 1991, and January 1995. We evaluated prospectively recorded clinical data and retrospective chart analysis for transfusion-related information. RESULTS: The median number of transfusions per infant decreased from 7 in the first period to 2 in the third period, whereas donor exposure decreased from 5 to 1 and blood volume transfused decreased from 131 to 37 mL/kg birth weight (P <.01). The median venous hematocrit measured before transfusion decreased from 43% to 35% in infants who underwent ventilation and from 41% to 31% in spontaneously breathing infants. The median birth weight decreased from 870 to 740 g and the median gestational age from 27 to 25 completed weeks (P <.01). The overall survival rate was 75% and did not change. The incidences of retinopathy, intraventricular hemorrhage, and patent ductus arteriosus remained unchanged. CONCLUSION: Over this 9-year period with increasingly restrictive transfusion guidelines, the transfusion number decreased by 71% and the donor exposure by 80% in ELBW infants without adverse clinical effects.

A point mutation Thr(799)Met on the alpha(2) integrin leads to the formation of new human platelet alloantigen Sit(a) and affects collagen-induced aggregation.

A new platelet-specific alloantigen, termed Sit(a), was identified in a severe case of neonatal alloimmune thrombocytopenia. The Sit(a) alloantigen is of low frequency (1/400) in the German population. Immunochemical studies demonstrated that the Sit(a) epitopes reside on platelet glycoprotein (GP) Ia. Nucleotide sequence analysis of GPIa cDNA derived from Sit(a)-positive platelets showed C(2531)-->T(2531) point mutation, resulting in Thr(799)Met dimorphism. Analysis of genomic DNA from 22 Sit(a)-negative normal individuals showed that the Thr(799) is encoded by ACG(2532) (90.9%) or ACA(2532) (9.1%). To establish a DNA typing technique, we elucidated the organization of the GPIa gene adjacent to the polymorphic bases. The introns (421 bp and 1.2 kb) encompass a 142-bp exon with the 2 polymorphic bases 2531 and 2532. Polymerase chain reaction-restriction fragment length polymorphism analysis on DNA derived from 100 donors using the restriction enzyme Mae III showed that the Met(799) form of GPIa is restricted to Sit(a) (+) phenotype. Analysis of stable Chinese hamster ovary transfectants expressing allele-specific recombinant forms of GPIa showed that anti-Sit(a) exclusively reacted with the Glu(505)Met(799), but not with the Glu(505)Thr(799) and the Lys(505)Thr(799) isoforms. In contrast, anti-Br(a) (HPA-5b) only recognized the Lys(505)Thr(799) form, whereas anti-Br(b) (HPA-5a) reacted with both Glu(505)Thr(799) and Glu(505)Met(799) isoforms. These results demonstrated that the Met(799) is responsible for formation of the Sit(a) alloantigenic determinants, whereas amino acid 505 (Lys or Glu) specifically controls the expression of Br(a) and Br(b) epitopes, respectively. Platelet aggregation responses of Sit(a) (+) individuals were diminished in response to collagen, indicating that the Thr(799)Met mutation affects the function of the GPIa/IIa complex.

Effect of C1-inhibitor in a rat model of necrotizing enterocolitis.

Our aim was to investigate the effect of C1-inhibitor (C1-INH) in a rat model of necrotizing enterocolitis (NEC). Twenty-four anesthetized and artificially ventilated rats received 0.1 mg/kg endotoxin. Fifteen minutes later, the animals in the study group (n = 12) were treated with 200 IU/kg C1-INH whereas the control animals (n = 12) received normal saline. In all animals, FiO(2) was reduced after 90 min from 0.21 to 0.05 and ventilation continued until 180 min or death. All animals developed shock symptoms. Drop in mean arterial blood pressure was more pronounced and survival time was shorter in the control group. Whereas the C1-INH activity increased in the study group, it decreased in the control group. The extent of macroscopic intestinal lesions did not differ between the groups. In conclusion, C1-INH did not prevent shock, but mitigated and delayed its course.

3-D ultrasound quantification of neonatal cerebral ventricles in different head positions.

We determined the influence of head position on lateral ventricular cerebral volume in low-birth-weight infants by three-dimensional (3-D) ultrasound (US). Thirty-nine neonates were examined prospectively in a controlled and blinded study. We used a freehand 3-D US system to acquire data sets after head positioning for 3 h on left and right side in random order. The borders of the lateral ventricles were marked in stored cross-sections. Volumes were calculated as mean of duplicate measurements. Median volume of lateral cerebral ventricles was 1.03 (quartiles 0.78-1.36) mL. Median left ventricular volume was slightly larger than right one (p = 0.13). Down-side lateral ventricles showed smaller volumes than up-side positioned ventricles (p < 0.01). Freehand 3-D US allows quantification of small volumes as neonatal lateral cerebral ventricles. Head position influences the lateral cerebral ventricle volume in low-birth-weight infants.

Thrombopoietin concentration in umbilical cord blood of healthy term newborns is higher than in adult controls.

Thrombopoietin (TPO) concentrations were determined in umbilical cord plasma of 121 healthy term newborns. The lower detection limit of the enzyme immunoassay employed was 32.5 pg/ml. Median cord plasma TPO concentration was 78 (interquartile range 55-107) pg/ml. 95th percentile was 255 pg/ml. In only 8% (10/121), TPO was below the detection limit compared to 81% of healthy adults (25/31). In cord blood and adult controls, there were no significant correlations of TPO with platelet count or mass.

3-D sonographic volume measurement of the cerebral ventricular system: in vitro validation.

This in vitro study evaluates the accuracy and observer dependency of a freehand three-dimensional (3-D) ultrasound system for measuring cerebral ventricular volume in infants. A sphere, a cylinder, and three cerebral ventricle phantoms were made of agarose and embedded in an echogenic matrix after measuring true volumes by water displacement. Volumes of the models were calculated by 3-D software after manual contour marking on ultrasound cross-sections. Mean +/- SD sonographic volume was 94.6%+/-7.3% (n = 130) of true volumes. Intraobserver variation (n = 10) was 2.3%-5.3% for complete investigation (scanning and marking), and 1.8%-4.1% for marking alone. Difference of means (n = 10) between two observers was 7.6% to 10.8% for complete investigation, and 0.6% to 1.6% for the marking process. We conclude that 3-D freehand ultrasonography may be useful for examining ventricle dilatation in infancy.

Complete blood counts from umbilical cords of healthy term newborns by two automated cytometers.

Complete blood counts (CBC) of umbilical cord blood from 123 healthy term newborns were simultaneously performed with two different cytometers using laser as a light source. Medians (95% range) were: WBC 14.2 (7.8-24.3) x 10(9)/l, platelets 265 (174-363) x 10(9)/l, Hb 15.7 (12.5-18.2) g/dl, RBC 4.6 (3.9-5.5) x 10(12)/l, MCV 106 (95-113) fl, PCV 0.49 (0.40-0.56), and MCH 33.8 (30.3-36.4) pg. Reticulocytes were 149 (95-212) x 10(9)/l or 3.3 (2.0-4.7)%; erythroblasts 5 (0-24) per 100 WBC or 0.53 (0.00-3.20) x 10(9)/l. The counters agreed well except for MCHC. WBC counts showed the smallest difference irrespective of erythroblast number; platelets showed the largest difference. The lower limit for normal Hb should be fixed at 12.5 g/dl for the adequate diagnosis of anaemia from cord blood of term newborns.

Acidosis activates complement system in vitro.

We investigated the in vitro effect of different forms of acidosis (pH 7.0) on the formation of anaphylatoxins C3a and C5a. Metabolic acidosis due to addition of hydrochloric acid (10 micromol/ml blood) or lactic acid (5.5 micromol/ml) to heparin blood (N=12) caused significant activation of C3a and C5a compared to control (both p=0.002). Respiratory acidosis activated C3a (p=0.007) and C5a (p=0.003) compared to normocapnic controls. Making blood samples with lactic acidosis hypocapnic resulted in a median pH of 7.37. In this respiratory compensated metabolic acidosis, C3a and C5a were not increased. These experiments show that acidosis itself and not lactate trigger for activation of complement components C3 and C5.

Anaphylatoxins in fresh-frozen plasma.

BACKGROUND: Fresh-frozen plasma (FFP) is widely used in patients with coagulation disorders and simultaneous complement activation. Complement activation in FFP itself is poorly investigated. STUDY DESIGN AND METHODS: The concentration of anaphylatoxins C3a and C5a, the complement precursors C1q and factor B, and complement function were measured in 40 consecutively administered FFP units in two pediatric neonatal intensive care units. In 12 samples, the measurements were also performed after incubation with inulin. RESULTS: In 15 of 40 FFP units, both anaphylatoxin concentrations were below the upper cutoff levels reported for healthy humans (C3a, 500 microg/L; C5a, 5 microg/L). Anaphylatoxin levels were higher in FFP units produced by apheresis than in those from blood donation. Complement activation of FFP by inulin increased anaphylatoxin concentration, whereas C1q and factor B levels, and complement function remained unchanged. CONCLUSION: Elevated concentrations of anaphylatoxin are frequently found in FFP units produced by apheresis. Studies are necessary to investigate the reasons for complement activation and the possibilities of prevention during apheresis. As the concentrations of complement precursors and complement function did not change with activation in FFP, these studies should include measurement of the anaphylatoxins C3a and C5a.

[Complete remission of a highly malignant, progressive under therapy Wilm's tumor using the combination carboplatin and etoposide (VP 16)]. / Vollremission eines unter Therapie progredienten Wilms-Tumors hohen Malignitätsgrades durch die Kombination von Carboplatin und Etoposid (VP 16).

A Wilms' tumor in a 4 year old girl did not diminish under preoperative chemotherapy following SIOP 9/GPO study guidelines. Surgery revealed an anaplastic (high grade) nephroblastoma infiltrating pancreas, transverse colon, and diaphragm. During postoperative treatment with ifosfamide, vincristine, actinomycin D, and doxorubicin, there was massive tumor growth per continuitatem in chest and abdomen within 6 weeks. Following a French study for relapsed Wilms' tumor, we gave 160 mg/m2 carboplatin and 100 mg/m2 etoposide on 5 consecutive days. After only one cycle, the tumor showed already remarkable regress. We applied six cycles of carboplatin/etoposide and a abdominal radiation. At the end of therapy, the patient was in complete remission. Side effects of chemotherapy were severe bone marrow aplasia and a moderate and reversible decrease of creatinine clearance. The combination of carboplatin and etoposide is a promising therapy in Wilms' tumor resistant to classic nephroblastoma drugs like vincristine, doxorubicin, and actinomycin D.

Vitamin D dependent rickets type II with myelofibrosis and immune dysfunction.

We present a new patient with vitamin D dependent rickets type II. A 20-month-old Arabian boy whose parents are first cousins showed florid rickets, myelofibrosis and recurrent septicaemia. In addition to absent specific binding for 1,25-dihydroxyvitamin D3 (1,25(OH)2D3). 25-Hydroxyvitamin D3-24-hydroxylase activity could not be induced in cultured fibroblasts. The patient did not respond to 99 micrograms 1,25(OH)2D3 per day, but skeletal and haematological abnormalities improved with daily infusion of 100 mg/kg calcium, as serum parathyroid hormone levels fell to normal values. At the age of 7 years, he died from pneumonia. The improvement of haematological abnormalities with calcium infusions but not with 1.25(OH)2D3 suggests a pathogenetic relationship of myelofibrosis and hyperparathyroidism. Having anti-lipid A IgM antibody titres up to 1:10.000 after Gram negative septicaemias, the patient never produced corresponding IgG antibodies. His neutrophil chemotaxis was persistently reduced to 57% +/- 3% of age-matched controls (P less than 0.028). The patient showed two pathological immune functions considered to contribute to the well-known susceptibility to infection in rickets.

[Controlled immunoglobulin therapy in immune hemolytic anemia by positive pool immunoglobulin fluorescence test]. / Gezielte Immunglobulintherapie einer immunhämolytischen Anämie bei positivem Pool-Immunglobulin-Fluoreszenz-Test.

An Italian boy with homozygous beta-thalassemia showed a shortening of transfusion intervals at the age of three years. He had a positive direct antiglobulin test (DAT) because of C3d-loaded red blood cells without any detectable erythrocytic antibody. Serologic investigations indicated a recent EBV infection. Pool immunoglobulin fluorescence test (PIT) revealed a loading of red blood cell membranes with antigens. Oral prednisone therapy did not show any effect. After a single infusion of 400 mg immunoglobulin per kg body weight decrease of hemoglobin concentration slowed down to the rate before crisis. DAT and PIT became negative. The immune hemolytic crisis was possibly due to erythrocyte loading with EBV antigen that caused activation of the alternate complement pathway. Detection of antigen loaded red blood cells by PIT suggested a immunoglobulin therapy in order to coat the structures promoting hemolysis. Thus, a positive PIT seems to be a criterion for successful application of immunoglobulins in immune hemolytic anemia.