Peng-Hong Yang

Clinical and radiographic spectrum of septic pulmonary embolism

Aims: To review the clinical presentation, radiographic findings, and outcome of therapy in children with septic pulmonary embolism. Methods: Retrospective analysis of patients in a tertiary paediatric facility in northern Taiwan. Results: Ten children were identified with septic pulmonary emboli in a four year retrospective chart review between 1998 and 2001. Seven were immunocompetent, two were premature infants, one had β thalassemia major. Seven had community acquired staphylococcal infections and bacteraemia, of which six were methicillin resistant Staphylococus aureus (MRSA) isolates. Five had soft tissue infections, two bone infections, one suppurative otitis media, one catheter related infection, and one unknown foci of infection. Multiple and bilateral nodular pulmonary parenchymal lesions were common on plain chest radiographs, but chest computed tomography scans showed the additional findings of a “vessel sign” and central cavitations, confirming the existence of septic pulmonary embolism. Conclusions: Community acquired MRSA infections occurred in seven patients with septic pulmonary embolism but without predisposing high risk factors. Critically ill children with skin, soft tissue, or bone infections, when associated with septic pulmonary embolism in an area with a high rate of MRSA, should be empirically treated with glycopeptides (such as vancomycin or teicoplanin) before susceptibility results are known, in order to minimise morbidity and avoid mortality.

Vallecular cyst: an uncommon cause of stridor in newborn infants

Abstract Vallecular cyst, a rare but generally benign lesion in the larynx, may cause stridor and even life-threatening airway obstruction in early infancy. We retrospectively studied 14 cases of newborn infants with vallecular cyst. There was no gender predilection and most cases were full-term and appropriate for gestational age. The clinical presentations included stridor, chest wall retraction, feeding difficulties and failure to thrive. Laryngomalacia was the most common associated anomaly. Flexible laryngoscopy was sufficient for diagnosing the vallecular cyst and larygmalacia. Maintenance of airway patency, nutritional support, and de-roofing of the cyst were the mainstays of management. Conclusion Vallecular cyst should be included in the differential diagnosis of stridor in newborn infants. Respiratory and feeding difficulties in these patients can be dramatically improved after appropriate surgical removal of the cyst.

Prevalence and Pathogen Distribution of Neonatal Sepsis Among Very-Low-Birth-Weight Infants

BACKGROUND Neonatal sepsis contributes to great mortality and morbidity among very-low-birth-weight (VLBW) infants. Prevalence and pathogen distribution of sepsis in the neonatal intensive care units (NICUs) vary with time and geographic location. Such information serves as a guide for selection of empirical antibiotics coverage. METHODS This is a case series study performed by retrospective chart review of VLBW infants (birth body weight, BBW, <1500 g) in a medical center during a 5-year period from January 2005 to December 2009. Episodes of positive blood cultures, pathogen distribution and related clinical manifestations were described. RESULTS A total of 158 episodes of sepsis were identified from 1042 VLBW infants. Sepsis rate was 152 per 1000 live births. The vast majority of infections (60.7%) were caused by Gram-positive organisms [G(+)], and overall Coagulase-negative staphylococci (CoNS) (52.5%) were the most common pathogen identified. Prevalence for early-onset sepsis (EOS) was 1% and for late-onset sepsis (LOS) was 14.2%. Infants with EOS had a much higher case fatality rate than LOS (40% vs. 4.7%). Escherichia coli (40%) were the leading pathogen of EOS while CoNS (54.7%) was the leading pathogens of LOS. Overall, apnea and/or bradycardia and/or cyanosis (65.8%), poor activity (48.7%), and increased respiratory effort (43.0%) were the most common presenting features of sepsis. CONCLUSION Unlike term infants, Gram-negative organism and E coli were the leading pathogen of EOS among VLBW infants. Judicious and timely use of antibiotic therapy is crucial in the care of VLBW infants.

Group B Streptococcal Infection in Taiwan: Maternal Colonization and Neonatal Infection

BACKGROUND There is no national data on group B streptococcus (GBS) infection in Taiwan. We investigated incidence of maternal GBS colonization and neonatal GBS infection rate and clinical pictures of neonatal GBS infection to estimate the value of intrapartum chemoprophylactic strategy in Taiwan. METHODS From January 2004 to June 2005, a prospective study to estimate maternal colonization rate by maternal rectovaginal culture at six hospitals was conducted. Neonatal GBS infection rate based on inborn infants was calculated retrospectively from January 2001 to June 2005; clinical pictures of infants diagnosed with invasive GBS disease were reviewed. RESULTS Maternal colonization rate of GBS was around 20% at hospital base, incidence of neonatal GBS infection was 1 per 1000 live births of infants born at hospitals. There were 221 infants with GBS infection: in 142, the disease occurred within 7 days of birth (early-onset disease, EOD), and in 79, it developed later (late-onset disease). Infantile EOD was more often seen in mothers with premature rupture of membrane, often accompanied by respiratory failure necessitating ventilator support. Infants with late-onset disease often manifested fever, leukopenia, thrombocytopenia, and meningitis. Fifteen infants died, mostly of EOD type (12 of 15). Risk factors of mortality included rescue at delivery room, leukopenia, thrombocytopenia, sepsis, respiratory distress, persistent hypertension of newborn, respiratory failure needing intensive respiratory support (intermittent mandatory ventilator and high frequency oscillatory ventilator), surfactant use, shock, and congenital heart diseases. CONCLUSIONS We concluded that universal maternal rectovaginal culture of GBS with intrapartum antibiotic prophylaxis is an urgent call to reduce EOD and mortality because of GBS infection in neonates in Taiwan.

Neonatal listeriosis in Taiwan, 1990—2007

OBJECTIVES Listeria monocytogenes is an important pathogen in neonates in Western countries, with a fatality rate of 20-30%. There is limited information on neonatal listeriosis in Eastern countries. The purpose of this study was to delineate the occurrence and clinical picture of neonatal listeriosis in Taiwan. METHODS A questionnaire-based survey of all of the 17 medical centers in Taiwan was performed, and a literature review of neonatal listeriosis as reported in Taiwan from 1990 to 2007 was made. RESULTS A total of 14 cases (10 male, four female) of neonatal listeriosis were identified, including 11 found from the survey of four medical centers and another three collected from the literature review. Three were found to have occurred prior to 2000 and 11 were found to have occurred after 2000. The age of onset was less than 3 days in all cases. L. monocytogenes was identified from blood in 13, cerebrospinal fluid in four, and gastric aspirate in two. Half of the cases (7/14) had involvement of the central nervous system with pleocytosis and hypoglycorrhachia in cerebrospinal fluid, and three of them even developed hydrocephalus. The mortality rate was 29%. CONCLUSIONS Our findings suggest that listeriosis may emerge as an important health threat among newborn infants in Taiwan.

Serum Lactate, Brain Magnetic Resonance Imaging and Outcome of Neonatal Hypoxic Ischemic Encephalopathy after Therapeutic Hypothermia

BACKGROUND Serum lactate was used to predict the severity and outcome of neonatal hypoxic ischemic encephalopathy (HIE) before the era of therapeutic hypothermia (TH). There is no report on neurodevelopment (ND) outcome of neonates with HIE treated with TH in Taiwan. METHODS Between April 2011 and December 2012, newborn infants admitted to Chang Gung Memorial Hospital (CGMH), with gestational age > 35 weeks and birth weight ≥ 1800 g, who had acute perinatal events, evidence of significant fetal compromise, and ongoing clinical encephalopathy were prospectively enrolled for TH. Whole body cooling method was used to maintain the affected neonates esophageal temperature at 33.5 ± 0.5 °C for 72 hours. Demographic data were recorded and hemogram, biochemical parameters, serum lactate, and creatine kinase (CK) were measured as well. Brain magnetic resonance imaging (MRI) was performed between 7 and 14 days of life. ND outcome of infants was evaluated by Bayley Scales of Infant Development, third edition (BSID-III) at 24 months of corrected age. Poor ND (PND) outcome was defined as infants surviving with either disability or ND delay. RESULTS Seventeen patients were enrolled. Fifty-nine percent of babies (10/17) were born through cesarean section and 77% of babies (13/17) were transferred from outside hospitals. Six babies were moderate HIE and 11 babies were severe HIE. Among the 14 surviving patients, eight infants had PND outcome. There was no difference in demographic data between infants with and without PND. Serum level of lactate (mg/dL) after 72 hours of TH was higher (35.6 vs. 13.8, p = 0.042) in infants with PND. Neonates with abnormal brain MRI findings were also associated with PND (p = 0.01). CONCLUSION This is the first report on ND outcome of neonates with HIE treated with TH in Taiwan. Higher serum level of lactate following TH and abnormal results of brain MRI are associated with poor ND outcome.

Clinical Impacts of Delayed Diagnosis of Hirschsprung’s Disease in Newborn Infants

BACKGROUND Asian infants are at a higher risk of having Hirschsprungs disease (HD). Although HD is surgically correctable, serious and even lethal complications such as Hirschsprungs-associated enterocolitis (HAEC) can still occur. The aim of this study was to investigate the risk factors of HAEC, and the clinical impacts of delayed diagnosis of HD in newborn infants. PATIENTS AND METHODS By review of medical charts in a medical center in Taiwan, 51 cases of neonates with HD between 2002 and 2009 were collected. Patients were divided into two groups based on the time of initial diagnosis: Group I, diagnosis made within 1 week after birth, and Group II after 1 week. Clinical features including demographic distribution, presenting features of HD, short-term and long-term complications related to HD were compared between the two groups of patients. RESULTS There were 25 patients in Group I and 19 in Group II. Group II patients had more severe clinical signs and symptoms of HAEC than Group I patients. The incidence of preoperative HAEC was 12% in Group I and 63% in Group II (adjusted odds ratio = 12.81, confidence interval = 2.60-62.97). Patients with preoperative HAEC were more likely to develop adhesive bowel obstruction after operation (33% vs. 3%, p = 0.013) and failure to thrive (33% vs. 3%, p = 0.013). Also, patients with long-segment or total colonic aganglionosis were at risk of developing both postoperative HAEC (85% vs. 29%, p = 0.001) and failure to thrive (39% vs. 3%, p = 0.002). CONCLUSION In our study, we found that delayed diagnosis of HD beyond 1 week after birth significantly increases the risk of serious complications in neonatal patients. Patients with long-segment or total colonic aganglionosis have higher risk of postoperative HAEC and failure to thrive. Patients with preoperative HAEC are more likely to have adhesive bowel obstruction and failure to thrive.

Red Blood Cell Transfusion and Clinical Outcomes in Extremely Low Birth Weight Preterm Infants.

BACKGROUND Red blood cell (RBC) transfusion is often considered a life-saving measure in critically ill neonates. The smallest and least mature infants tend to receive the largest amount of transfusions. RBC transfusion itself has also been suggested as an independent risk factor of poor clinical outcome in critical patients. Our aim is to study if there are associations between RBC transfusion and in-hospital mortality, short-term morbidities, and late neurodevelopmental outcome in extremely low birth weight (ELBW) preterm infants. METHODS A cohort of ELBW preterm infants admitted to our neonatal intensive care unit from January 2009 to December 2010 were recruited. The number of RBC transfusions within 7 days, 30 days, and 60 days of life were recorded. Clinical outcomes including in-hospital mortality, development of retinopathy of prematurity (ROP), necrotizing enterocolitis, chronic lung disease, and later neurodevelopmental outcome were assessed with follow-up of up to 2 years of age. Multivariable logistic regression was used to estimate the associations between RBC transfusion and clinical outcomes. RESULTS A total of 98 ELBW preterm infants survived at the time of discharge. Of these survivors, the mean numbers of RBC transfusions were 2.5 ± 1.7, 7.4 ± 3.1, and 11.3 ± 4.5 times within 7 days, 30 days, and 60 days after birth, respectively. The number of transfusions within 7 days of life was correlated with risk of death before 1 month of age (odds ratio: 1.54, 95% confidence interval: 1.04-2.27, p = 0.03) and the number of transfusions within 30 days was correlated with risk of developing threshold ROP (odds ratio: 1.27, 95% confidence interval: 1.04-1.55, p = 0.02). The number of transfusions within 7 days of life was positively correlated with cognitive performance (Mental Developmental Index score) at 18-24 months of corrected age. CONCLUSION RBC transfusion has a negative impact on survival in ELBW infants. It increases the risk of developing ROP and affects late neurodevelopment. Decisions of blood transfusion in these very immature infants should be made cautiously taking these deleterious results into consideration.

Unusual Presentation of Renal Vein Thrombosis in a Preterm Infant

Neonatal renal vein thrombosis is the most common vascular condition in the newborn kidney, which could lead to serious complication in infants undergoing intensive care. In this study, we report the case of a preterm infant with left renal vein and inferior vena cava thrombosis, presented with gross hematuria, thrombocytopenia, transient hypertension, and adrenal hemorrhage. Supportive care was offered instead of heparin therapy or thrombolytic agents. In conclusion, our case teaches that, despite the lack of a clinically obvious shock event, renal vein thrombosis should be considered in a macrohematuric newborn without renal failure.

Limited Diagnostic Value of Routine Screening of Neonates with the Urinary Group B Streptococcal Antigen Tests

BACKGROUND A urinary latex test for detection of antigens from group B Streptococcus (GBS) has been used for the diagnosis of invasive GBS disease. However, the value of routine screening of infants with this test has not been determined. METHODS All infants admitted to Linkou Chang-Gung Memorial Hospital (Taoyuan, Taiwan) from January 2005 to May 2013 were screened with a urinary GBS antigen test (Wellcogen Strep B). Medical records were retrospectively reviewed to determine the diagnostic value of this test. RESULTS A total of 14,277 infants were tested and 38 cases had confirmed diagnoses of invasive GBS disease (34 bacteremia, 18 meningitis, 14 both), corresponding to a prevalence of 0.27% among our admitted infants. A total of 106 infants had positive results, but only 26 had confirmed disease. Among infants with confirmed disease, 12 had negative antigen results. These data allowed calculation of the sensitivity (68.4%), specificity (99.4%), positive predictive value (24.5%), and negative predictive value (99.9%). Adjusting for prevalence, the disease probability of a positive test result was 23.6%, and the probability of a negative post-test result was 0.09%. The absolute risk reduction of a negative result was very small (0.18%). Analysis of demographic, clinical, and laboratory parameters indicated that late age of onset (≥7 days-old), presence of seizure, fever, respiratory distress, leukopenia, bandemia, thrombocytopenia, coagulopathy, metabolic acidosis, and elevated levels of C-reactive protein (CRP) were significantly related to the presence of a true positive test result. CONCLUSION In our study population, the positive predictive value of the GBS antigen test was poor and the risk reduction of a negative result was weak. These results indicate that routine screening with this test has a limited diagnostic value. However, GBS antigen testing appears to be useful for early detection of disease in infants with certain demographic, clinical, and laboratory risk factors.