A clinical and microbiological study of puerperal sepsis in a tertiary care hospital in India

Objective: This prospective study was carried out to evaluate the clinical profile and bacterial isolates among women with puerperal sepsis in a tertiary hospital in North India.

Materials and methods: Women with puerperal sepsis (n?=?45) admitted from January 2015 to April 2016 were followed prospectively. Cultures were obtained from cervix, blood, urine, and pyoperitoneum. Initial antibiotics were cefotaxime or piperacillin with tazobactam plus amikacin plus clindamycin or metronidazole and were changed according to sensitivity.

Results: Out of 7887 deliveries during this period, 45 (0.2%) women had puerperal sepsis. 16 (35.5%) delivered in the present hospital, 25 (55.5%) at another health care facility, and 4 (8.9%) at home. Delivery was by cesarean section (CS) in 24/45 (53.3%) and vaginal in 21/45 (46.6%). Grade 1 sepsis occurred in 21, grade 2 in two, and grade 3 in 22 women. Majority (29/45 or 64.5%) had no risk factor for puerperal sepsis. There were two (4.4%) deaths and 13/45 (28.8%) had near-miss morbidity. Pathogenic bacteria were isolated in 33/45 (73.3%) in cervical swab (69%), blood, urine, or pus culture with no significant difference in the bacterial yield or species isolated between cotton or polyester swabs (p?>?.05). Escherichia coli were the commonest isolate and was sensitive to amikacin in all. Five had stillbirths and 4/40 neonates developed sepsis but recovered.

Conclusions: Escherichia coli was the commonest pathogen and was uniformly sensitive to amikacin, which may be included among the initial antibiotics to treat puerperal sepsis in India.     

Intestinal mucosal alterations in rats with carbon tetrachloride-induced cirrhosis: changes in glycosylation and luminal bacteria

Spontaneous bacterial peritonitis is a major cause of mortality after liver cirrhosis. Altered permeability of the mucosa and deficiencies in host immune defenses through bacterial translocation from the intestine due to intestinal bacterial overgrowth have been implicated in the development of this complication. Molecular mechanisms underlying the process are not well known. In order to understand mechanisms involved in translocation of bacteria, this study explored the role of oxidative stress in mediating changes in intestinal mucosal glycosylation and luminal bacterial content during cirrhosis. CCl4-induced cirrhosis in rats led to prolonged oxidative stress in the intestine, accompanied by increased sugar content of both intestinal brush border and surfactant layers. This was accompanied by changes in bacterial flora in the gut, which showed increased hydrophobicity and adherence to the mucosa. Inhibition of xanthine oxidase using sodium tungstate or antioxidant supplementation using vitamin E reversed the oxidative stress, changes in brush border membrane sugar content, and bacterial adherence. In conclusion, oxidative stress in the intestine during cirrhosis alters mucosal glycosylation, accompanied by an increased hydrophobicity of luminal bacteria, enabling increased bacterial adherence onto epithelial cells. This might facilitate translocation across the mucosa, resulting in complications such as spontaneous bacterial peritonitis.     

Relative percentage signal intensity recovery of perfusion metrics—an efficient tool for differentiating grades of glioma

Objective:

Glioma classification and characterization may be facilitated by a multiparametric approach of perfusion metrics, which could not be achieved by conventional MRI alone. Our aim is to explore the potential of relative percentage signal intensity recovery (rPSR) values, in addition to relative cerebral blood volume (rCBV) and relative cerebral blood flow (rCBF) of first-pass T₂* dynamic susceptibility contrast (DSC) perfusion MRI, in differentiating high- and low-grade glioma.

Methods:

This prospective study included 39 patients with low-grade and 25 patients with high-grade glioma. rPSR, rCBV and rCBF were calculated from the first-pass T₂* DSC perfusion MRI. rPSR was calculated using standard software and validated with dedicated perfusion metrics analysis software. The statistical analysis was performed using analysis of variance and receiver operating characteristic (ROC) curves.

Results:

Variation in rPSR, rCBV and rCBF values between low- and high-grade gliomas were statistically significant (p < 0.005). The ROC curve analysis for each of them yielded 96% sensitivity and 71.8% specificity; 88% sensitivity and 69.2% specificity; and 72% sensitivity and 66.7% specificity. The area under the curve (AUC) from the ROC curve analysis yielded 0.893, 0.852 and 0.702 for rPSR, rCBV and rCBF, respectively. The rPSR calculation with the validation software yielded 92.3% sensitivity and 72% specificity with an AUC of 0.864.

Conclusion:

rPSR inversely correlates while rCBV and rCBF values directly correlate with the tumour grade. Furthermore, the overall diagnostic performance of rPSR is better than rCBV and rCBF values.

Advances in knowledge:

rPSR of T₂* DSC perfusion is an indicator of blood–brain barrier status and lesion leakiness, which has not been explored yet compared with the usual haemodynamic parameters, rCBV and rCBF.Gliomas, the most common primary brain tumour of the brain, are heterogeneous, showing highly varied histopathological features during malignant transformation of the tumour reflecting alterations in the tumour vasculature.¹ The broad category of glioma represents approximately 30% of all the tumours. Low-grade astrocytomas (60–70%) and oligodendrogliomas (10–30%) are two common subtypes of low-grade gliomas. Among them, glioblastoma and astrocytoma account for 75% of gliomas.² With the advent of advanced imaging technologies, heterogeneity in gliomas such as neovascularization, angiogenesis, loss of blood–brain barrier (BBB) integrity, tortuousness, disorganized and highly permeable vessels may be non-invasively measured with the help of perfusion imaging.^3–5 Dynamic susceptibility contrast (DSC) perfusion MRI is a widely accepted tool for evaluating the haemodynamic characteristics of the brain, which are of great interest since it helps in assessing the malignancy of the tumour. The common haemodynamic parameters assessed using perfusion MRI are relative cerebral blood volume (rCBV) and relative cerebral blood flow (rCBF).^6–8 In this study, we use a comparatively newer parameter, relative percentage signal intensity recovery (rPSR), whose potential has not been exploited to its best for haemodynamic calculations, even though this parameter has shown promise in the differentiation of brain tumours.^9–11 PSR is the percentage of the signal intensity recovered at the end of the first pass of the contrast agent with respect to the pre-contrast baseline signal intensity. After the administration of the contrast agent, there is a sudden decrease in the signal intensity owing to the variation in the local magnetic field leading to T₂* decay, which is seen as a dip in the mean signal intensity–time curve, and then the signal returns towards the baseline.^9–11The tumour rCBV provides information about the tumour blood levels and degree of angiogenesis but fails to provide information regarding capillary permeability. This drawback of DSC-MR perfusion imaging can be addressed by evaluating the rPSR obtained from the signal intensity–time curve formed at the end of the first pass of contrast agent in DSC-MR perfusion imaging.^9,10 Previous studies have observed that the contrast agent leakage, size of the extravascular space and the rate of blood flow that reflects the alterations in capillary permeability are related to rPSR.^10,11 There are reports which state that information regarding capillary permeability and lesion leakiness can be gathered from the signal intensity–time curve obtained from the first-pass T₂* DSC perfusion. Usually, this is performed using dynamic contrast-enhanced perfusion MRI, which involves additional scan time and also post-processing assumptions and extrapolations.^9–11Lupo et al⁴ was the first to report the characterization of high-grade gliomas using the PSR and peak height. rPSR is the only parameter among the different perfusion metrics which takes into account the leakage factor for the characterization of heterogeneity of brain tissues, compared with the other two parameters rCBV and rCBF where the leakage is neglected during the evaluation. The rPSR values of lower grade gliomas have not been explored, and hence an effort to differentiate between high- and low-grade gliomas using this new parameter will be advantageous. Hence, in the present study, we have evaluated all the parameters rPSR, rCBV and rCBF of low- and high-grade gliomas to find the potential of rPSR to differentiate different grades of glioma over the other two conventionally used parameters rCBV and rCBF. rPSR values were evaluated using two different standard software programs. Furthermore, we have performed a test for correlation between these parameters.     

Relationship between complex fractionated electrograms (CFE) and dominant frequency (DF) sites and prospective assessment of adding DF-guided ablation to pulmonary vein isolation in persistent atrial fibrillation (AF)

Dominant Frequency Mapping and Ablation . Background: Sites of high DF are potential targets for AF ablation, but it is unknown if addition of DF ablation can improve procedural outcome. Objectives: We sought to (1) examine the relationship between DF sites and complex fractionated electrograms (CFE) and (2) prospectively assess the long‐term outcome of adding DF ablation to pulmonary vein antral isolation (PVAI) for persistent AF. Methods: First, 20 patients with persistent AF who underwent previous CFE‐guided ablation and who had AF terminate during ablation were studied retrospectively (group I). Bipolar, 8‐second electrograms were collected by a circular catheter (288 ± 86 points/map). The EnSite NavX system allows for automated display of both CFE and DF maps. Electrograms with cycle length <120 ms were considered CFE and were compared to DF sites > 8 Hz (direct inverse relationship). Sites of AF termination were related to CFE and DF sites. Based on these observations, 30 different patients (group II) with persistent AF prospectively underwent DF‐guided ablation plus PVAI. They were followed every 3 months for 1 year (visit, Holter, ECG). These patients were compared to case‐matched controls undergoing PVAI alone (group III). Results: In group I, there was a significant, inverse correlation between DF and CFE values at each point (r =–0.24, P < 0.001). DF surface area was less than CFE area (27 ± 5 cm² vs 34 ± 4 cm², P = 0.03). CFE sites overlapped 48 ± 27% with the DF surface area. Nonoverlapping CFE sites were contiguous to DF sites. AF termination occurred where DF and CFE overlapped, and at these sites, DF was always greater than the mean DF for the map. In group II, all DF sites above the mean value were prospectively ablated during AF. AF termination was noted in only 2/30 (7%) patients. After DF ablation, PVAI was performed and termination increased to 4/30 patients (14%). At 1 year, freedom from atrial arrhythmia > 30 seconds occurred in 57% of DF+PVAI compared to 60% in patients receiving PVAI alone (P = 0.18). Conclusions: DF and CFE regions overlap only about 50%. AF termination retrospectively occurred on overlapping CFE/DF sites where DF was above the mean. However, prospective ablation of DF sites plus PVAI resulted in low AF termination rates, and did not improve 1 year success over PVAI alone. (J Cardiovasc Electrophysiol, Vol. 22, pp. 1309‐1316, December 2011)     

Effect of vaginally administered (Ala)-magainin II amide on the morphology of implantation stage endometrium in the rhesus monkey (Macaca mulatta)

Intravaginal administration of an anti-microbial agent, (Ala^8,13,18)-magainin II amide, during blastocyst implantation inhibits pregnancy establishment in a dose-related manner in the rhesus monkey (Macaca mulatta). In the present study, mated female rhesus monkeys were vaginally inserted with tampons containing vehicle (Group 1; N = 5) and test agent (magainin, 0.5 mg/animal; Group 2; N = 6) on cycle day 20. Endometrial tissue samples were collected on Cycle Day 24 from all monkeys and processed for morphometric and ultrastructural analysis. Concentrations of estradiol-17β, progesterone, and chorionic gonadotrophin in peripheral circulation were determined, which revealed that two monkeys in Group 1 were pregnant while no animals were pregnant in Group 2. Endometrial morphology, however, revealed histologic evidence of pregnancy in three out of the six magainin-treated animals. It appears that intra-vaginal administration of magainin II amide had a marginal effect on the implantation stage endometrium and the initiation of the implantation process in the rhesus monkey.     

Update on PPHN: Mechanisms and treatment

Persistent pulmonary hypertension of the newborn (PPHN) is a syndrome of failed circulatory adaptation at birth, seen in about 2/1000 live born infants. While it is mostly seen in term and near-term infants, it can be recognized in some premature infants with respiratory distress or bronchopulmonary dysplasia. Most commonly, PPHN is secondary to delayed or impaired relaxation of the pulmonary vasculature associated with diverse neonatal pulmonary pathologies, such as meconium aspiration syndrome, congenital diaphragmatic hernia, and respiratory distress syndrome. Gentle ventilation strategies, lung recruitment, inhaled nitric oxide, and surfactant therapy have improved outcome and reduced the need for extracorporeal membrane oxygenation (ECMO) in PPHN. Newer modalities of treatment discussed in this article include systemic and inhaled vasodilators like sildenafil, prostaglandin E1, prostacyclin, and endothelin antagonists. With prompt recognition/treatment and early referral to ECMO centers, the mortality rate for PPHN has significantly decreased. However, the risk of potential neurodevelopmental impairment warrants close follow-up after discharge for infants with PPHN.     

Separation and function of neutrophil karyogranuloplasts and comparison with cytoplasts and intact cells

Since neutrophjl cytoplasts lacking nucleus and granules were first prepared by centrifuging neutrophils over a discontinuous Ficoll gradient containing cytochalasin B, several functional deficits have been reported in these cytoplasts. Although these functional deficits have been considered to originate from the absence of organelles, cell damage during preparation could not be excluded. Therefore, in the following experiments the Ficoll gradient was modified to isolate both cytoplasts and karyogranuloplasts, which have a nucleus and granules and represent the cell after loss of the cytoplast. Electron microscopy and analysis of marker proteins and cell volume showed that karyogranuloplasts were distinct from neutrophils. The phorbol myristate acetate (PMA) orN-formylmethionylleucylphenylalanine (FMLP) -induced O ₂ ^– release, corrected by surface area, was in the following order: neutrophils > cytoplasts > karyogranuloplasts. Both aggregation and membrane potential depolarization were maximal in neutrophils, intermediate in karyogranuloplasts, and lowest in cytoplasts when either PMA or FMLP was used as a stimulant. Extracellular release of the granule contents (degranulation) was triggered by FMLP in both neutrophils and karyogranuloplasts. Cytochalasin B pretreatment greatly enhanced FMLP-induced O ₂ ^– release, degranulation, aggregation, and depolarization of membrane potential in neutrophils and karyogranuloplasts, but not in cytoplasts. The ability of cytochalasin B to potentiate FMLP-triggered cell function probably depends on granules or cell organelles which are depleted in cytoplasts. Chemokinesis and chemotaxis were impaired in both karyogranuloplasts and cytoplasts. Specific FML[³H]P binding was greater in karyogranuloplasts than in cytoplasts. Cellular actin content, measured by the DNase I inhibition assay, was abundant in cytoplasts and was extremely low in karyogranuloplasts. Karyogranuloplasts retain various neutrophil functions, except for chemotaxis, and provide an important control when studying the role of cell organelles in cytoplast function.     

Pregnancy associated spontaneous coronary artery dissection: A case report and review of literature

BACKGROUNDPregnancy-associated spontaneous coronary artery dissection (PSCAD) is an important cause of chest pain and acute myocardial infarction in pregnant and postpartum women. Pregnancy is considered an isolated risk factor for spontaneous coronary artery dissection. The etiology, pathogenesis, and incidence of PSCAD are not known.CASE SUMMARYWe present a case of a 33-year-old postpartum female who presented with sudden onset chest pain and was diagnosed with spontaneous coronary artery dissection and needed urgent catheterization revealing left anterior descending coronary artery dissection. She underwent emergent coronary artery bypass graft surgery with good post-operative recovery.CONCLUSIONMost patients with PSCAD can be managed conservatively with medical management and have good outcomes. Patients with high-risk presentations benefit from the invasive approach. Coronary artery bypass graft may be required in select few patients based on angiography findings. Due to the risk of recurrent spontaneous coronary artery dissection, subsequent pregnancies are discouraged.