[Gaussian distribution of intelligence in VLBW preterm infants at age 5: very low correlation with very low birth weight]. / Normalverteilung der Intelligenz von VLBW-Frühgeborenen mit 5 Jahren: sehr geringe Korrelation mit sehr geringem Geburtsgewicht.

BACKGROUND: Preterm infants with very low birth weight < 1500 g (VLBW) have a higher risk of developmental disorders. In addition to the common estimation of the mean intelligence values, we studied the distribution of intelligence at preschool age in VLBW infants and the risk factors influencing this distribution. PATIENTS AND METHODS: A prospective cohort study of 277 VLBW infants < 32 weeks born in 1991-1995 and treated according to a standardized regimen in one Perinatal Center was carried out, including measurement of intelligence (Kaufman-Assessment Battery for Children) at age 5. Statistical methods employed were: explorative data analysis, correlation, chi (2)- and t-tests; the tested variables were: small for gestational age (< third percentile), perinatal acidemia (umbilical arterial pH < 7.10), perinatal hypoxia (BE < - 10), hypothermia (< 36 degrees C), hypoglycemia after the first day of life (< 30 mg / dL), bronchopulmonary dysplasia (FiO (2) > 0.21 > or = 36 weeks), intraventricular hemorrhage, ventricular dilation, periventricular leukomalacia, seizures, abnormal acoustic evoked potentials, and hyperexcitability at discharge. RESULTS: The distribution of intelligence in 137 VLBW infants < 32 weeks (60 % follow-up rate) was similar to a symmetrical Gaussian bell curve. The intelligence increased very slightly with birth weight (Pearson correlation: 0.172; p = 0.045) and was significantly lower in children with hypoglycemia after the first day of life (- 13.35; 95 % confidence interval: - 20.08 to - 6.63; p = 0.002), hyperexcitability at discharge (- 16.28; 95 % confidence interval: - 25.26 to - 7.31; p = 0.005), and bronchopulmonary dysplasia (- 7.00; 95 % confidence interval - 11.71 to - 2.29; p = 0.039). CONCLUSIONS: At preschool age, the intelligence of VLBW infants is normally distributed and correlates only slightly with the very low birth weight. Hypoglycemia after the first day of life and bronchopulmonary dysplasia are risk factors for lower intelligence. Hyperexcitability at discharge seemed to represent a promising prognostic factor for a later intelligence reduction.

[Non-haemorrhagic subependymal pseudocysts: ultrasonographic, histological and pathogenetic variability]. / Nichthämorrhagische subependymale Pseudozysten: sonografische, histologische und pathogenetische Variabilität.

PURPOSE: Differentiation of non-haemorrhagic subependymal pseudocysts from subependymal pseudocysts after cerebral haemorrhage in the preterm infant. MATERIALS AND METHODS: Selective ultrasonographic screening in 2200 neonates and retrospective analysis in 72 infants with subependymal pseudocysts, the full-term infants being analysed from birth, and the preterm infants after the second week of life, thus avoiding the gestational age at which cerebral haemorrhage occurs in the preterm infant. RESULTS: Three variants of pseudocysts were identified: the caudothalamic germinolysis is a leukomalacic and pseudocystic gliosis. Pseudocysts in the anterior choroid plexus of the lateral ventricle could be distinguished from caudothalamic germinolysis by their location, form and movement. Pseudocysts lateral of the frontal horns are the result of regression of germinal matrix remains. CONCLUSION: Differentiation of non-haemorrhagic from post-haemorrhagic germinolysis is necessary to clarify the aetiology and pathogenesis of non-haemorrhagic pseudocysts. Caudothalamic germinolysis possibly is the result of infection with stenotic intima proliferation following vasculitis. The results are thalamostriatal vasculopathy and germinal necrosis. Anterior plexus cysts might be the result of folding faults of the ependyma in the growth period of the choroid plexus. Pseudocysts lateral of the frontal horns should not be mistaken for ventricular ligaments.

Stacking structure of concentrated shear ordered dispersions by two scattering methods.

In this paper, the ordering in concentrated charge stabilized colloidal dispersions is considered. Despite the impressive Bragg reflections obtained for shear ordered dispersions by light (LS), small-angle neutron (SANS), and small-angle X-ray scattering (SAXS), a number of open questions remain. Sheared dispersions are usually ordered in layers. For such systems, two questions arise: (1) What is the structure in a layer? (2) What is the stacking structure perpendicular to the layers? The second question requires a method to determine the structure perpendicular to the layers. Although originally interested only in structural aspects, we were forced to consider different methods. Two methods are treated both applicable to neutron and X-ray scattering from concentrated dispersions. One has been used by physicists and chemists for many years to determine the structure of crystals by sample rotation. In colloid science, we have used it previously in neutron and X-ray scattering. A second method is treated here which can be applied in small-angle scattering from a Couette cell. It gives the scattering intensity in a certain direction without sample rotation. Although very useful with the Couette cell, it cannot be found in any of the well-known references on colloid science. A theoretical explanation and experimental examples obtained by synchrotron X-ray scattering from a Couette cell are given in the paper.

[Transthoracic pacing in a very low birth weight infant with congenital complete atrioventricular block - Case report]. / Kongenitaler AV-Block III degrees bei einem Frühgeborenen von 832 g: Möglichkeiten der passageren Herzschrittmacher-Therapie.

We report our experience of pacemaker treatment in a premature infant of 832 grams with congenital complete atrioventricular block due to maternal Sjögren's Syndrome. She was delivered by cesarean section at an estimated gestational age of 26 weeks because of fetal bradycardia, decreasing fetal movements and hydrops. Immediate postnatal transesophageal ventricular pacing was not successful, whereas transthoracic pacing with self-adhesive patch electrodes adapted to body size resulted in an effective increase of the infant's heart rate until operative application of temporary epimyocardial pacing wires ensured the external stimulation of the heart.

[Results of a National Survey in Germany on incidence and therapy of the nonoliguric hyperkalemia of the premature infant]. / Nichtoligurische Hyperkaliämie Frühgeborener - Ergebnisse einer nationalen Umfrage zur Inzidenz und zur Therapie mit Salbutamol.

BACKGROUND: Although nonoliguric hyperkalemia of the premature infant is a common problem, in many hospitals it is not observed. It is characterized by an excessive increase in serum potassium concentration (serum-[K (+)]) at 24 hours after birth. Recently, salbutamol has been recommended to treat hyperkalemia. There are no controlled trials in premature infants. During the first minutes of salbutamol infusions paradoxical increases in serum-[K (+)] may occur. We asked for possible reasons for the variable incidence of the disorder. We wanted to know if salbutamol is currently applied and if initial increases in serum-[K (+)] during salbutamol infusions have been observed. MATERIALS AND METHODS: National survey in Germany. RESULTS: Questionnaires of 132 hospitals caring for premature infants < 30 gestational weeks. The incidence of hyperkalemia was 0 - 40 %. At least 25 % of all hospitals measured serum-[K (+)] not before the second day after birth. 52 hospitals had applied salbutamol. Nine hospitals reported increases in serum-[K (+)] associated with salbutamol therapy. However, it was common practice to measure serum-[K (+)] 1 hour (median, range 0.25 - 12 hours) after the start of the infusion. Two cases of cardiac arrhythmias during salbutamol infusion were reported. DISCUSSION AND CONCLUSIONS: The variable incidence of hyperkalemia may result from the fact that many hospitals do not measure serum-[K (+)] on the first day after birth. Common practice made it potentially impossible to determine the frequency of initial increases in serum-[K (+)] during salbutamol infusion. However, these data should be available, before controlled trials on salbutamol treatment in premature infants can be initiated.

[Intrauterine therapy and outcome in four pregnancies of one mother with anti ro-autoantibody positive Sjoegren's syndrome]. / Intrauterine Therapie und kindliche Entwicklung bei vier Schwangerschaften einer Mutter mit Sjögren-Syndrom und Anti-Ro-Autoantikörpern.

Autoantibodies against 52/60kD-Ro proteins, frequently present in patients with Sjoegren's Syndrome or systemic lupus erythematosus, are transmitted to the fetus during pregnancy. These autoantibodies can damage the cardiac conductive system of the fetus and cause a complete atrioventricular block, with a mortality of 30 %. We report the intrauterine therapy during four pregnancies of the same mother with high 52/60kD-Ro autoantibodies and the outcome of her infants. Our patient with primary Sjoegren's Syndrome suffered an early miscarriage during her first pregnancy. During the second pregnancy, a fetal atrioventricular block was observed at 23 weeks of gestation. Although subsequently dexamethasone therapy and daily plasmaphereses were started, a cesarean section was necessary at 26 weeks due to hydrops fetalis. The girl died from the atrioventricular block after two days. During the third and fourth pregnancies, dexamethasone therapy was begun already at 7 weeks, and regular plasmaphereses at 15 weeks. The children were delivered by cesarean section at 32 and 36 weeks because of growth retardation. Both had normal electrocardiograms after birth and after 2 and 4 years. In pregnant women with connective tissue diseases, monitoring of anti Ro-autoantibodies and fetal heart function is important. Intrauterine therapeutic options are dexamethasone therapy to suppress maternal and fetal inflammatory reactions and repeated plasmaphereses to reduce autoantibody levels. Postnatal follow up of the infants for atrioventricular block and rheumatic manifestations is necessary.

Fungal brain abscesses in neonates: Sonographic appearances and corresponding histopathologic findings.

Extremely preterm neonates and neonates with predisposing conditions such as congenital or acquired immunodeficiency are at high risk for systemic fungal infection. Abscess formation in the brain is a severe complication that occurs in 70% of neonates with systemic fungal infection. Cerebral sonography can be used to diagnose abscesses in the brain in these patients. We report 2 sonographic presentations of fungal brain abscesses in neonates confirmed by postmortem histopathologic examination. The first patient, an extremely preterm neonate of 23 weeks' gestation with a systemic Candida albicans infection, had multiple small, round, hypoechoic lesions with echogenic rims in both brain hemispheres. The second patient, a term neonate with disseminated aspergillosis and DiGeorge syndrome, had a few large echogenic areas in the right periventricular region. Brain imaging should be considered in the diagnostic workup in neonates with suspected systemic fungal infection. Cerebral involvement can be diagnosed at the bedside with cerebral sonography.

Growth and development of children to 4 years of age after repeated antenatal steroid administration.

UNLABELLED: It is common practice to repeat antenatal steroid administration after 7 to 10 days in women who continue to be at risk for preterm delivery. However, safety and efficacy of repeated courses have not been established. Mothers of singleton infants who had more than five courses of betamethasone (80-120 mg cumulative dose) were eligible for this cohort study. Index patients (IP) were compared to concurrent controls who had < or = 1 course but were matched for sex and gestational age. Of 35 IP born between 1986 and 1995 in a single perinatal centre, 28 were available for follow-up and could be matched. There was no difference between groups with respect to maternal age and gestational age at delivery. Median gestational age at initial treatment was 26.3 weeks (25th percentile 25.1 weeks, 75th percentile 27.2 weeks) in IP. There was no significant difference between groups in head circumference, length and body weight at birth and at age 4 years. The ability to sit and to walk without assistance and to use two-word phrases was attained at similar ages. The use of glasses or hearing aids, allergies, asthma or recurrent upper respiratory infections were not reported more frequently in IP. CONCLUSION: This study failed to ascertain adverse long-term effects of repeated antenatal steroid administration in infants and children to the age of 4 years. In contrast to a similar Australian study, we were unable to demonstrate a lower birth size in exposed infants even though our sample size for women with more than five courses and their cumulative doses were larger.

[Oral sugar solutions in pain therapy of neonates and premature infants]. / Orale Zuckerlösungen in der Schmerztherapie von Neu- und Frühgeborenen.

OBJECTIVES: We review the efficacy of oral sugar solutions for treating procedural pain in neonates and address the following questions: Do newborns need analgesic therapy for procedural pain during blood sampling? How do sugars influence pain-reactions of neonates? What is the efficacy of sugar solutions in clinical practice? METHODS: We searched for relevant articles in the PubMed database from 1990 to September 2000. RESULTS: Treatment of procedural pain in newborns is desirable because they are more sensitive to pain than adults, they show marked pain reactions during blood sampling and repeated acute pain in the newborn period results in longterm behavioural changes. Oral sugar solutions have been studied for treatment of procedural pain in neonates. Their initial effect is the result of orotactile stimulation by the intraoral fluid. The orogustatory stimulation by the sweet taste prolongs the effect for up to 10 minutes through endorphin release. In randomized-controlled trials oral sugar solutions (2 ml of 25% sucrose or 30% glucose) reduced pain reactions and crying and attenuated the heart rate increase after capillary and venous blood sampling in term and preterm neonates. They are more effective than traditional calming strategies, like cuddling by parents, use of a pacifier, or breast feeding. Yet, sugar solutions provide no adequate analgesia for more severe pain, e.g. during circumcision. CONCLUSIONS: Sugar solutions effectively relieve procedural pain during blood sampling in neonates. Additional studies are needed to determine the minimal effective dose and the efficacy and side effects of repeated sugar doses in the same patient.

In vitro validation and clinical testing of an indirect calorimetry system for ventilated preterm infants that is unaffected by endotracheal tube leaks and can be used during nasal continuous positive airway pressure.

Energy expenditure measurements in ventilated preterm infants are difficult because indirect calorimetry underestimates energy expenditure during gas leaks around uncuffed endotracheal tubes routinely used in preterm infants or during nasal continuous positive airway pressure (CPAP). We, therefore, developed a breath collector that simultaneously sampled expired air expelled at the ventilator outlet and escaping via the tube leak from the infant's mouth and nose. Our breath collector was combined with a proprietary calorimeter (Deltatrac II). In vitro validation was done by methanol burning (VO(2), 13.8 mL/min; VCO(2), 9.2 mL/min) during intermittent positive pressure ventilation (IPPV) with two commonly used ventilators (Sechrist IV-100B and Infant Star). Measurement error was determined at different ventilator flows, peak inspiratory pressures of 12-24 cm H(2)O, and during a complete tube leak. The mean measurement error with both ventilators was low (VO(2) +/- 3 %, VCO(2) +/- 2 %) even during a complete tube leak and did not increase with peak inspiratory pressure. The system response time was 2 min. In vivo measurements at the bedside were performed in 25 preterm infants (body weight, 537-1402 g). Energy expenditure during IPPV was 40 +/- 9 kcal/kg per day and 46 +/- 15 kcal/kg per day during nasal CPAP. The tube leak in the preterm infants studied during IPPV was 0 to 47 %, and during nasal CPAP 84 to 97 %. In conclusion, indirect calorimetry performed with our breath collector was accurate during IPPV and nasal CPAP and was unaffected by tube leaks.

The diversity of rearranged immunoglobulin heavy chain variable region genes in peripheral blood B cells of preterm infants is restricted by short third complementarity-determining regions but not by limited gene segment usage.

The immunoglobulin diversity is restricted in fetal liver B cells. This study examined whether peripheral blood B cells of extremely preterm infants show similar restrictions (overrepresentation of some gene segments, short third complementarity-determining regions [CDR3]). DNA of rearranged immunoglobulin heavy chain genes was amplified by polymerase chain reaction, cloned, and sequenced. A total of 417 sequences were analyzed from 6 preterm infants (25-28 weeks of gestation), 6 term infants, and 6 adults. Gene segments from the entire V(H) and D(H) gene locus were rearranged in preterm infants, even though the D(H)7-27 segment was overrepresented (17% of rearrangements) compared to term infants (7%) and adults (2%). CDR3 was shorter in preterm infants (40 +/- 10 nucleotides) than in term infants (44 +/- 12) and adults (48 +/- 14) (P <.001) due to shorter N regions. Somatic mutations were exclusively found in term neonates and adults (mutational frequency 0.8% and 1.8%). We conclude that preterm infants have no limitations in gene segment usage, whereas the diversity of CDR3 is restricted throughout gestation.

Focal congenital alveolar proteinosis associated with abnormal surfactant protein B messenger RNA.

Two siblings presented with typical clinical features of congenital pulmonary alveolar proteinosis (PAP). Necropsy of one sibling revealed scattered foci of the diagnostic histologic changes in the lung tissue. In contrast to infantile and adult PAP, focal distribution is uncommon in congenital PAP. Defective expression of the granulocyte-macrophage colony-stimulating factor receptor was ruled out. The surfactant protein B (SP-B) content in the lung tissue of the autopsied patient was low, and a deletion in the SP-B messenger RNA was detected. We speculate that the PAP in our patients was related to the reduced quantity and/or to the altered quality of SP-B.

Do we need new indications for ECMO in neonates pretreated with high-frequency ventilation and/or inhaled nitric oxide?

OBJECTIVE: High-frequency ventilation (HFV) and/or inhaled nitric oxide (iNO) has reduced ECMO in neonates. But, frequently, improvement with HFV/iNO is temporary and only prolongs lung injury without preventing ECMO. We tried to identify a threshold oxygenation index (OI) that predicts temporary or persistent improvement with HFV/iNO in neonatal ECMO candidates as early as possible. DESIGN: Cohort study of all neonates with OI > 40 during intermittent positive pressure ventilation between 1992 and 1997. The first treatment was HFV; at an OI > 40 during HFV, iNO was added; at an OI > 40 during HFV+iNO, ECMO was initiated. Temporary improvement was defined as secondary need for ECMO or fatal chronic lung disease without ECMO. SETTING: University hospital level III neonatal intensive care unit. MAIN RESULTS: Ten of the 34 neonates studied rapidly required ECMO despite HFV/iNO. Eleven neonates temporarily improved for 1-10 days before the OI was again > 40. Nine received ECMO, two were denied ECMO after mechanical ventilation > 14 days and died of chronic lung disease. Thirteen neonates persistently improved with HFV/iNO without ECMO. The OI before, at 24 h or 48 h of HFV/iNO did not predict temporary or persistent improvement. However, after 72 h of HFV/iNO, neonates with persistent improvement had lower OIs than those with temporary improvement [median OI 16 (4-24) vs 31 (20-40); P = 0.0004]. In all neonates with an OI > or = 25 after 72 h, HFV/iNO eventually failed (positive predictive value 100%, sensitivity 91 %, specificity 100%, positive likelihood ratio 91). CONCLUSION: For neonates pretreated with HFV/iNO, an OI > 40 is an inadequate ECMO indication. Based on our data we hypothesize that an OI > or = 25 after 72 h of HFV/ iNO is a better ECMO indication that avoids prolonged barotrauma.

Leukocyte and endothelial activation in a laboratory model of extracorporeal membrane oxygenation (ECMO).

An inflammatory response and a capillary leak syndrome frequently develop during the treatment of neonatal respiratory failure by extracorporeal membrane oxygenation (ECMO). The present study was performed to investigate leukocyte activation and endothelial cell dysfunction that are associated with prolonged contact of blood components with synthetic surfaces. Laboratory ECMO was performed with fresh human blood at 37 degrees C for 8 h (n = 6). Leukocyte activation was measured by L-selectin (CD62L) and CD18 integrin surface expression and by neutrophil-derived elastase release. To monitor endothelial activation, endothelial cell ICAM-1 (CD54) expression was measured in cultured endothelial cells from human umbilical veins (HUVEC) after incubation with plasma from the ECMO experiments. CD18 integrin expression was found significantly up-regulated on polymorphonuclear neutrophils and monocytes after 2-4 h of laboratory ECMO. L-selectin was reduced on both cell types during the total duration of the experiments. Soluble L-selectin (sCD62L) and total and differential leukocyte counts remained unchanged during the experiment. Neutrophil-derived elastase content was maximal after 8 h of ECMO. Plasma from the ECMO experiments did not induce ICAM-1 expression of cultured HUVEC. We conclude that prolonged contact with synthetic surfaces during ECMO activates phagocytes, which may contribute to the inflammatory response seen in ECMO-treated patients. Activated phagocytes do not accumulate in the extracorporeal system nor release humoral factors inducing ICAM-1 expression on endothelial cells.

Postnatal changes of extracellular volume, atrial natriuretic factor, and diuresis in a randomized controlled trial of high-frequency oscillatory ventilation versus intermittent positive-pressure ventilation in premature infants <30 weeks gestation.

OBJECTIVES: High-frequency oscillatory ventilation (HFOV) with a high lung volume strategy is an experimental mode of ventilating preterm infants aimed at achieving maximal alveolar recruitment Higher mean airway pressures are used during HFOV than during intermittent positive-pressure ventilation (IPPV), and the intrathoracic volume increase is relatively constant. Both factors increase the risk to depress organ blood flow and diuresis. Our objective was to test the hypothesis that high lung volume HFOV attenuates the postnatal reduction of extracellular volume in preterm infants by reducing plasma atrial natriuretic factor and diuresis. DESIGN: Prospective, randomized, controlled clinical trial. SETTING: University hospital, Level III neonatal intensive care unit. PATIENTS: Premature infants <30 wks gestation requiring intubation for respiratory distress syndrome within the first 6 hrs of life; 15 infants (gestational age, 26 [24-29] wks, birth weight 814 [452-1340] g) were randomized to HFOV, 19 infants (gestational age 27 [24-39] wks, birth weight 930 [644-1490] g) to IPPV. INTERVENTIONS: The randomized mode of ventilation was assigned within 1 hr after intubation. During HFOV mean airway pressure was increased as long as oxygenation improved and no lung overinflation was seen on chest radiograph. IPPV rates were > or =60/min. MEASUREMENTS AND MAIN RESULTS: We measured extracellular volume (sucrose dilution) and atrial natriuretic factor on Day 1 and Day 3. Mean airway pressure, body weight, diuresis, and fluid intake were measured daily. During HFOV mean airway pressure was higher at 12 hrs (median 7 cm H2O vs. 4 cm H2O; p = .001) and 24 hrs (median 6 cm H2O vs. 3 cm H2O; p = .01). In both groups, extracellular volume decreased between Day 1 and Day 3 (HFOV from 428 +/- 126 mL to 344 +/- 145 mL [p = .003], IPPV from 466 +/- 108 mL to 414 +/- 124 mL [p = .01]) and diuresis increased (HFOV, from 2.5 +/- 1.7 to 4.6 +/- 0.9 mL/kg/hr [p = .001]; IPPV, from 2.8 +/- 1.6 to 4.2 +/- 1.0 mL/kg/hr [p = .01]). Plasma atrial natriuretic factor was not decreased in the HFOV group. CONCLUSIONS: High lung volume HFOV as primary mode of ventilation in preterm infants <30 wks gestation did not result in unwanted fluid retention and a decrease in diuresis in the first days of life.

Transthoracic pacing in a very low birth weight infant with congenital complete atrioventricular block.

We report our experience of pacemaker treatment in a premature infant of 830 g with congenital complete atrioventricular block due to maternal Sjögren's Syndrome. The infant was delivered by cesarean section at an estimated gestational age of 26 weeks because of fetal bradycardia, decreasing fetal movements, and hydrops. Immediate postnatal transesophageal ventricular pacing was not successful, whereas transthoracic pacing with self-adhesive patch electrodes adapted to body size resulted in an effective increase of the infant's heart rate until operative application of temporary epimyocardial pacing wires allowed external stimulation of the heart.

[Hearing screening of high risk newborn infants]. / Hörscreening von Neugeborenen mit Risikofaktoren.

OBJECTIVE: This prospective study reports on the prevalence of hearing impairment in an at-risk neonatal intensive care unit (NICU) population. DESIGN: From 1990 to 1998, 1062 neonates were screened with the use of transitory evoked otoacoustic emissions (TEOAE) and brainstem evoked response audiometry (BERA). RESULTS: 934 infants passed the primary screen for both ears, 75 for one ear, adding up to 95%. 17 infants (1.6%) were lost to follow-up. In fourteen infants (1.3%), bilateral hearing impairment above 30 dB was confirmed. While all children with hearing impairment belonged to the group of 862 children receiving aminoglycosides, only one of them presented no other risk factors. In twelve of the hearing impaired children other anamnestic factors, i.e. dysmorphism, prenatal rubella or cytomegaly, family history of hearing loss or severe peri- and postnatal complications seem to be more probable causes of the identified hearing loss. In one of these children, delayed onset or progression of hearing loss is suspected. CONCLUSIONS: From our data, aminoglycosides are not an important risk factor for hearing impairment, when serum levels are continuously monitored, as in our cohort. After adjustment for other risk factors, birth weight between 1000 gr and 1500 gr and a gestational age between 29 and 31 weeks were no predictive markers for hearing impairment. It might be speculated that the improved medical treatment in a NICU reduces the probability of hearing impairment for those two groups. Conductive hearing loss as a possible additional cause for hearing impairment was not studied in detail, but the high percentage of malformations detected (four out of fourteen hearing impaired infants) demands further monitoring, close follow-up, adequate treatment and counselling.

An outbreak of pyodermas among neonates caused by ultrasound gel contaminated with methicillin-susceptible Staphylococcus aureus.

OBJECTIVE: To investigate an outbreak of methicillin-susceptible Staphylococcus aureus (MSSA) infections in a neonatal clinic. DESIGN: Prospective chart review, environmental sampling, and genotyping by two independent methods: pulsed-field gel electrophoresis (PFGE) and randomly amplified polymorphic DNA polymerase chain reaction (RAPD-PCR). A case-control study was performed with 31 controls from the same clinic. SETTING: A German 1,350-bed tertiary-care teaching university hospital. RESULTS: There was a significant increase in the incidence of pyodermas with MSSA; 10 neonates in good physical condition with no infection immediately after birth developed pyodermas. A shared spatula and ultrasound gel were the only identified infection sources. The gel contained MSSA and was used for hip joint sonographies in all neonates. PFGE and RAPD-PCR patterns from 6 neonates and from the gel were indistinguishable and thus genetically related clones. The case-control study revealed no significant risk factor with the exception of cesarean section (P=.006). The attack rate by days of hip-joint sonography between April 15 and April 27, 1994, was 11.8% to 40%. CONCLUSIONS: Inappropriate hygienic measures in connection with lubricants during routine ultrasound scanning may lead to nosocomial S. aureus infections of the skin. To our knowledge this source of S. aureus infections has not previously been described.