Shih-Ming Chu

Risk factors and outcomes for multidrug-resistant Gram-negative bacteremia in the NICU.

OBJECTIVES: To assess the risk factors antibiotic therapy and outcomes of multidrug-resistant (MDR) Gram-negative bacilli (GNB) bacteremia in NICU patients. METHODS: Episodes of MDR GNB bacteremia were compared with a non-MDR GNB bacteremia group in an 8-year cohort study. RESULTS: Of 1106 bacteremias, 393 (35.5%) were caused by GNB. Seventy (18.6%) were caused by an MDR strain. The most frequent mechanism of resistance was extended-spectrum β-lactamase production (67.1%), mainly by Klebsiella pneumoniae (59.6%). Previous antibiotic exposure to third-generation cephalosporin (odds ratio [OR]: 5.97; 95% confidence interval [CI]: 2.37–15.08; P < .001) and carbapenem (OR: 3.60; 95% CI: 1.26–10.29; P = .017) and underlying renal disease (OR: 7.08; 95% CI: 1.74–28.83; P = .006) were identified as independent risk factors for MDR GNB acquisition. Patients with MDR GNB bacteremia more likely received inadequate initial antibiotic therapy (72.9% vs 7.8%; P < .001) had higher rates of infectious complication (21.4% vs 10.5%; P = .011) and overall case fatality +rate (28.6% vs 10.5%; P < .001). Independent risk factors for overall mortality were presence of infectious complications after bacteremia (OR: 3.16; 95% CI: 1.41–7.08; P = .005) and underlying secondary pulmonary hypertension with or without cor pulmonale (OR: 6.19; 95% CI: 1.88–20.31; P = .003). CONCLUSIONS: MDR GNB accounted for 18.6% of all neonatal GNB bacteremia in the NICU, especially in those with previous broad-spectrum antibiotic therapy and underlying renal disease. The most frequent mechanism of resistance was extended-spectrum β-lactamase (ESBL) production. Neonates with MDR GNB were more likely to develop infectious complications, which were independently associated with a higher overall case-fatality rate.

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.

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.

Prognostic factors and concomitant anomalies in neonatal gastric perforation

OBJECTIVE Neonatal gastric perforation is a rare and serious issue. This study aimed to highlight the vital clinical features and identify prognostic factors in such cases. DESIGN, SETTING, PATIENTS, INTERVENTIONS, AND MEASUREMENTS Medical charts from January 1997 through December 2008 were reviewed retrospectively. Neonates with a diagnosis of gastric perforation were included. RESULTS Thirteen patients were identified with a male:female ratio of 9:4. Five (38%) were preterm infants. The mortality rate was 30% (4/13), and the median age of onset was 3 days (range: 1-14 days). The most common presenting sign was abdominal distension, followed by respiratory distress and vomiting. Except for one patient in whom gastric perforation was diagnosed during surgical repair for gastroschisis, all patients had pneumoperitoneum on admission; 70% and 46% of patients had peritonitis and sepsis, respectively. Concomitant gastrointestinal (GI) tract anomalies or disorders included ischemic bowel/necrotizing enterocolitis (5 patients), intestinal malrotation (2), duodenal web (1), hiatal hernia (1), and gastroschisis (1), which necessitated secondary operations during hospitalization in 5 patients. Seven patients had leukopenia on admission, and 9 developed thrombocytopenia in the following 48 h. All patients who died presented with leukopenia on admission and thrombocytopenia in the following 48 h, yielding sensitivity and specificity rates of 100% and 67%, respectively. CONCLUSIONS Neonatal gastric perforation is often concomitant with GI anomalies or inflammatory/infectious disease. Patients who were outborn and those with leucopenia, peritonitis, and thrombocytopenia development within 48 h were at risk for poor outcome.

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.

Clinical Manifestations, Outcomes, and Etiologies of Perinatal Stroke in Taiwan: Comparisons between Ischemic, and Hemorrhagic Stroke Based on 10-year Experience in A Single Institute

BACKGROUND Perinatal stroke is a common cause of established neurological sequelae. Although several risk factors have been identified, many questions regarding causes and clinical outcomes remain unanswered. This study investigated the clinical manifestations and outcomes of perinatal stroke and identified its etiologies in Taiwan. METHODS We searched the reports of head magnetic resonance imaging and computed tomography performed between January 2003 and December 2012. The medical records of enrolled infants with perinatal stroke were also reviewed. RESULTS Thirty infants with perinatal stroke were identified; 10 infants had perinatal arterial ischemic stroke (PAIS) and 20 had perinatal hemorrhagic stroke (PHS). Neonatal seizure was the most common manifestation and presented in 40% of infants with PAIS and 50% of infants with PHS. All survivors with PAIS and 77% of the surviving infants with PHS developed neurological sequelae. Acute seizure manifestation was associated with poststroke epilepsy in infants with PHS but not in infants with PAIS (86% vs. 0%, p=0.005). PAIS was mostly caused by dysfunctional hemostasis (20%) and embolism (20%), whereas PHS was mostly attributable to birth asphyxia (30%). CONCLUSION Perinatal stroke is associated with high mortality and morbidity rates in infants. Clinically, it can be difficult to distinguish PAIS and PHS. One should keep a high level of suspicion, especially for PHS, if infants develop unexplained seizure, cyanosis, conscious change, anemia, and/or thrombocytopenia. A systematic diagnostic approach is helpful in identifying the etiologies of perinatal stroke.