Trevor A. Macpherson

Chorioamnionitis, not epidural analgesia, is associated with maternal fever during labour

PurposeMaternal fever is associated with chorioamnionitis and has been linked to labour epidural analgesia (LEA). The purpose of this study was to determine possible associations between LEA and chorioamnionitis, maternal fever, operative delivery rate, and neonatal outcome.MethodsData from 14,073 patients were entered into a database over a two-year period. From this database, 62 nulliparous parturients with clinical chorioamnionitis (amnionitis), but without LEA were identified (Group I). Two other groups who received LEA were matched for parity and gestation: Group II — LEA with concomitant amnionitis (n = 50) and, Group III — LEA without concomitant amnionitis (n=201). The diagnosis of chorioamnionitis was confirmed by histologic examination. Results are expressed as mean ± SD and analyzed atP < 0.05 using ANOVA or Chi-square.ResultsNo differences were noted among the groups in the operative delivery rate or Apgar scores at five minutes. The percentage of patients with maternal fever during labour (38.0°C) with amnionitis was significantly less in Group III compared to the other groups (100% in both Groups I and IIvs 1.0% in Group III;P=0.000). Likewise, Group III had a lower percentage of neonates with Apgar scores < 7 at one minute (35.5% in Group I, 20.0% in Group II, 17.4% in Group III;P=0.010). The percentage of histologic chorioamnionitis was significantly higher in both amnionitis groups compared to Group III (67.7% in Group I, 56.0% in Group II, 4.0% in Group III;P=0.000).ConclusionLEA without chorioamnionitis is not associated with maternal fever (38.0°C), increased operative delivery rates or low Apgar scores.RésuméObjectifLa fièvre puerpérale est associée à la chorioamnionite et a été reliée à l’analgésie épidurale pendant le travail (AET). L’objectif de la présente étude était de déterminer les associations possibles entre AET et, chorioamnionite, fièvre puerpérale, taux de césarienne et évolution néonatale.MéthodePendant deux ans, on a inscrit dans une base de données les informations concernant 14 073 patientes. À partir de cette base de données, on a repéré 62 parturientes nullipares qui présentaient une chorioamnionite clinique, sans AET (groupe I). Deux autres groupes de femmes qui ont reçu une AET ont été appariés pour la parité et la gestation: le groupe II qui comportait une AET et une amnionite concomitante (n = 50), et le groupe III avec AET mais sans amnionite concomitante (n = 201). Le diagnostic de chorioamnionite a été confirmé par un examen histologique. Les résultats ont été exprimés par la moyenne ± l’écart type et analysés à P < 0,05 en utilisant une analyse de variance ou la méthode du Chi2.RésultatsAucune différence intergroupe n’est apparue quant au taux de césarienne ou à l’indice d’Apgar à cinq minutes. Le pourcentage de patientes atteintes de fièvre puerpérale pendant le travail (38,0°C) et d’amnionite a été significativement moindre dans le groupe III comparé aux deux autres groupes (100% dans les groupes I et II vs 1,0 % dans le groupe III; P = 0,000). Aussi, le groupe III a présenté un pourcentage plus faible de nouveaunés avec un indice d’Apgar < 7 à une minute (35,5 % dans le groupe I, 20,0 % dans le groupe II, 17,4 % dans le groupe III; P = 0,010). Le pourcentage de chorioamnionite histologique a été signifeativement plus élevé dans les deux groupes avec amnionite comparés au groupe III (67,7% dans le groupe 1, 56,0 % dans le groupe II, 4,0 % dans le groupe III; P = 0,000).ConclusionL’AET sans chorioamnionite n’est pas associée à la fièvre puerpérale (38,0°C), à un taux élevé de césarienne ou à un faible indice d’Apgar.

Localization of the Pa antigen on the placenta of the rat.

A unique class I MHC antigen, the Pa antigen, is the major immunogenic molecule on the placenta of the rat. It carries only a widely shared public antigenic determinant, and it is located on the basal trophoblast.

Initial Platelet Deposition at the Human Microvascular Anastomosis: Effect on Downstream Platelet Deposition to Intact and Injured Vessels

Initial platelet deposition (PD) in and around the region of a small-vessel anastomosis may set the stage for thrombosis and tissue loss. To study this problem, a human vessel model (human placental artery, HPA) has been designed to mimic the vascular injuries attendant on clinical microsurgery. To perform these studies, dissected lengths of human placental artery were treated to provide the following four types of injury: group I: control, dissected but otherwise uninjured (N = 5); group II: distal portion of vessel endothelium removed (N = 5); group III: central anastomosis, distal endothelium intact (N = 7); and group IV: central anastomosis, distal endothelium removed (N = 4). Vessels were perfused with 25 ml human whole blood for 17 ± 5 s at an average shear rate of 536 s−1. Vessels in groups I to IV were segmented at 2-cm intervals, and the number of 111In-labeled plateles was measured. Data from the following groups of exposure zones were pooled and analyzed: endothelium intact, endothelium absent, anastomosis present, postanastomosis with endothelium intact, and postanastomosis with endothelium absent. Significant numbers of platelets were found to attach to intact endothelium, indicating that ischemia and micro-surgical handling may augment platelet deposition to otherwise uninjured vessels. A similar degree of platelet deposition was measured after exposure of the subendothelium and perfusion, indicating that superficial subendothelial exposure in the absence of an additional prothrombotic stimulus may lead to no greater platelet deposition than occurs on slightly injured endothelium alone. Platelet deposition at anastomoses was strikingly elevated, although the anastomosis had no additive effect on platelet deposition to downstream endothelium. In contrast, an upstream anastomosis significantly augmented platelet deposition to exposed downstream subendothelium. (Plast. Reconstr. Surg. 90: 650, 1992.)

Necrotizing tracheobronchitis in intubated newborns: a complication of assisted ventilation.

This report describes a newly recognized iatrogenic lesion in newborns that we have termed necrotizing tracheobronchitis (NTB). Although it is related to assisted ventilation, it is different from previously described tracheal lesions in that it is most severe distal to the tip of the endotracheal tube and manifests a characteristic basophilic necrosis of the tracheal mucosa. Sloughing of tracheal mucosa, which occurs in the later stages, can cause respiratory obstruction. The lesion occurs over a wide range of gestational ages and birth weights as well as ventilatory rates, pressures, and supplemental oxygen concentrations. The severity of the lesion is related to the duration of ventilation. We believe NTB to be related to airflow through the endotracheal tube rather than to the effects of the tube itself because the lesion is worst beyond the end of the tube and extends into the major bronchi. A grading system is presented.

Maternal and fetal Toll-like receptor 4 genotype and chorionic plate inflammatory lesions

OBJECTIVE The objective of the study was to explore the relation between maternal and fetal genetic variation in Toll-like receptor 4 (TLR4) and chorionic plate inflammation STUDY DESIGN In this prospective observational cohort of 109 women with singleton gestations, 13 tag single nucleotide polymorphisms (SNPs) were genotyped in the TLR4 gene. The diagnosis of chorionic plate inflammation was made by a single blinded perinatal pathologist. RESULTS After adjustment for multiple comparisons, 1 maternal SNP (rs10759932) and 1 fetal SNP (rs1554973) in the TLR4 gene demonstrated highly significant association with chorionic plate inflammation. After adjustment for race, smoking, and bacterial vaginosis, carriage of these alleles was associated with chorionic plate inflammation (maternal rs1554973: odds ratio [OR] 5.2, 95% confidence interval, 3.2-6.4, P = .006; fetal rs10759932: OR 4.95, 95% confidence interval, 3.0-5.6, P = .005). There was no evidence of interaction between these 2 SNPs. CONCLUSION Maternal and fetal genetic variation in TLR4 is strongly associated with chorionic plate inflammation. This maternal and fetal genotypic effect are independent of each other as well as other environmental covariates.

Morphologic changes in the rat uterus following natural mating and embryo transfer.

ABSTRACT: In order to gain some insight into the putative immune suppression that may be induced at the placental implantation sites, the morphological changes at these sites following natural matings and following the transfer of embryos fertilized in vivo were studied. The only histologic parameter that showed a significant difference was the number of granulated metrial gland (GMG) cells. More GMG cells were present in allogeneic than in syngeneic pregnancies, and more GMG cells were present following embryo transfer into an allogeneic female than following the comparable natural mating. The role of the GMG cells in pregnancy is, however, still unresolved.

Eosinophilic Pyeloureteritis: Report of a Case

A case is reported of ureteral obstruction that was owing to eosinophilic pyeloureteritis, a previously unrecorded entity. The microscopic findings of extensive fibrosis and a relatively mild eosinophilic infiltrate were similar to those found in a series of eosinophilic cystitis, which was reported recently from this laboratory. Also, local injury appears to initiate some examples of eosinophilic cystitis and in the present case there was a striking history of injury 1 month before the symptoms of ureteral obstruction.

Prevalence of the neonatal autopsy: a report of the Study Group for Complications of Perinatal Care.

Neonatal autopsy findings are valuable additions to the information base for current cases and future perinatal care, so the reported decline in the autopsy rate is disturbing. In order to estimate the prevalence of the neonatal autopsy among a large population of deaths, we surveyed participating institutions of the Study Group for Complications of Perinatal Care. Investigators from 37 neonatal intensive care units, located in 9 childrens hospitals, 4 hospitals for women and infants, and 24 full-service pediatric and adult care hospitals, reported their neonatal death and autopsy rates for 1989. The overall neonatal autopsy rate was 51% among 1645 neonatal deaths. The rate was variable, ranging from 22 to 100%. We found the neonatal autopsy rate to be lower than previously reported and not apparently influenced by the type of center or by the type of medical staff at the centers. In order to assess and potentially reverse the current low rate, the influence of neonatal demographic and clinical factors, as well as physician-related factors, must be studied.

Vasospasm and platelet deposition in human arteries: effects of topical methylene blue.

Vasodilation of small blood vessels is controlled in part by the endothelium-derived relaxing factor (EDRF), which also inhibits platelet adhesion. Methylene blue (MB), which is occasionally applied directly to blood vessels during microsurgery to provide orientation and prevent torsion, is an irreversible inhibitor of the effects of endothelium-derived relaxing factor and may thereby augment both vasospasm and platelet responses. We have investigated the effects of the extravascular adventitial application of methylene blue on platelet deposition to human placental arteries (HPA) in the presence and absence of surgically induced vasospasm. A trend toward increased platelet deposition to human placental arteries was seen in each group but did not reach significance. The degree of platelet deposition to control human placental arteries suggests that the effects of methylene blue on platelet deposition may be dwarfed by the effects of surgical trauma and ischemia.

United States Medical Licensing Examination step 1 two-digit score: a correlation with the American Board of Pathology first-time test taker pass/fail rate at the University of Pittsburgh Medical Center.

CONTEXT Factors that correlate with success or failure on the American Board of Pathology (ABP) examination are not known. Other medical residency programs have shown that standardized test scores correlate with specialty board examination scores; however, data from pathology programs are lacking. OBJECTIVE To investigate whether the 2-digit score on step 1 of the United States Medical Licensing Examination (USMLE) was correlated with ABP examination performance at a large university pathology program. DESIGN Nine years of data (2001-2009) from pathology residents (n  =  72) at the University of Pittsburgh Medical Center (UPMC, Pittsburgh, Pennsylvania) was collected from existing files and deidentified. Step 1 USMLE 2-digit scores and ABP failure rates for first-time test takers were compared. Results are reported as the percentage of residents who failed either the anatomic pathology or clinical pathology part of the ABP examination in cohorts by their USMLE 2-digit score (≤80, 81-85, 86-89, ≥90). RESULTS The rolling 5-year (2005-2009) ABP average failure rate for first-time test takers of the anatomic pathology examination was 3.1% (UPMC) and 14.1% (nationally); in clinical pathology, it was 13.8% (UPMC) and 23.6% (nationally). At UPMC, no resident failed the anatomic pathology or clinical pathology parts of the ABP examination if his or her 2-digit USMLE step 1 score was 90 or more across 9 years of training (2001-2009). CONCLUSIONS In the UPMC pathology program, 2-digit scores on USMLE step 1 of 90 or more and 80 or less were strong measures of ABP first-time pass/failure rates, whereas scores of 81 to 89 were less-accurate measures. The USMLE step 1 score is one of many criteria that can be used for screening applicants for a pathology residency program.