A bundle of infection control measures reduces postoperative sternal wound infection due to Staphylococcus aureus but not Gram-negative bacteria: a retrospective analysis of 6903 patient episodes.

BACKGROUND: Prevention of cardiac surgical site infection has largely focused on reducing infection due to Staphylococcus aureus, although other bacteria also play an important role in this complication. AIM: To assess the impact of an evolving infection control programme on the incidence of sternal wound infection (SWI), and the changing incidence of non-staphylococcal infections. METHODS: A retrospective cohort study of all patients who underwent primary sternotomy at a single UK centre between September 2010 and May 2018 was undertaken. Data were collated from the 2 years preceding the stepwise introduction of a broad-ranging infection control programme, including S. aureus decolonization. FINDINGS: In total, 6903 primary sternotomies were performed, of which 2.6% (N=178) were complicated by SWI. Gram-negative bacteria (GNB) and S. aureus were most commonly identified as causative pathogens (45.5% and 30.3%, respectively). Following programme introduction, there was a reduction in the rate of SWI from 3.9 to 1.8 cases/100 patients/month. This was mainly due to a sustained reduction in cases of S. aureus infection, with no discernible impact on GNB. Multi-variable logistic regression analysis identified coronary artery bypass grafting, procedural urgency, and procedures performed in the third quarter of the calendar year (July to September) as independent risk factors for postoperative infection. CONCLUSION: A multi-faceted infection control programme was successful at reducing the rate of SWI, primarily due to a reduction in S. aureus infections. GNB also play an important role in SWI, and traditional preventative measures fail to address these. Future intervention and impact assessments should consider GNB infections when measuring effectiveness.

Small bowel ischaemia and perforation as a complication of Henoch-Schönlein Purpura in a previously healthy adult.

Henoch-Schönlein purpura is a small vessel vasculitis with multi-system manifestations that commonly affects children. We describe a case of new onset Henoch-Schönlein purpura in a previously healthy 42-year-old female who required an emergency laparotomy for small bowel perforation.

Intergenerational cycle of maltreatment: a popular concept obscured by methodological limitations.

OBJECTIVE: The intergenerational transmission of child maltreatment is a controversial subject. Much of existing research is plagued with at least three fundamental weaknesses: (1) using case status to define subjects: (2) adopting a dichotomous perspective that does not consider the reality of maltreatment on various continua; and (3) using operational definitions that fail to differentiate between maltreatment subtypes. We controlled for these problems and examined the structure of child maltreatment and its influence on later parenting practices in an ethnically-diverse community sample. METHOD: Data from a community sample of parents (N = 383) were analyzed with a Structural Equation Modeling methodology. Reliable and valid continuous measures of child maltreatment (Child Trauma Questionnaire) and parenting practices (Parental Acceptance and Rejection Questionnaire) were used. RESULTS: Results revealed a moderately strong effect from a general factor of Child Maltreatment to a general factor of Poor Parenting for both mothers and fathers, supporting a common dysfunction transmission process. For mothers. Family Neglect by itself also led to poor parenting, and sexual abuse as a child led to aggressive parenting. For fathers, Child Maltreatment had a different structure, as sexual abuse was distinct from the factors of Family Abuse and Family Neglect. Also, for fathers, sexual abuse led to rejecting parenting practices. CONCLUSIONS: This study supports the intergenerational cycle of child maltreatment hypothesis in such a way that several weaknesses in much of existing research were controlled. Clinical implications and potential mechanisms of transmission are discussed.

Alcohol involvement and dysphoria: a longitudinal examination of gender differences from late adolescence to adulthood.

Although numerous investigations have examined the relations between alcoholism and depression, differing results have emerged. Major limitations in existing work are that it uses clinical samples and is cross-sectional in nature. Using prospective data from a community sample assessed during 3 developmental periods (late adolescence, young adulthood, and adulthood), these complex relations were examined with structural equation modeling. Results show distinct gender differences between alcohol involvement and dysphoria. For women these 2 processes were related from late adolescence to adulthood, and this relation was reflected in a higher order construct that was stable over time. For men alcohol involvement and dysphoria were unrelated during late adolescence but converged over time. Reciprocal relations between alcohol involvement and dysphoria were found for both men and women.

Malignant vascular tumours of the pleura in "asbestos" workers and endothelial differentiation in malignant mesothelioma.

BACKGROUND: Three cases of diffuse malignant vascular tumours of the pleura are described which mimicked malignant mesothelioma clinically and pathologically (so called "pseudomesothelioma"). All had occupational histories of exposure to asbestos. The relationship of these tumours to mesothelioma and asbestos exposure is discussed. METHODS: To examine the histogenetic relationship between mesothelioma and these three tumours an immunohistochemical analysis of vascular marker (CD31, CD34, and Von Willebrand factor) expression was undertaken in 92 cases of pleural mesothelioma, in addition to these three tumours. Electron microscopic fibre analysis of lung tissue was performed on each of the three cases to assess asbestos fibre content. RESULTS: Diffuse pleural epithelioid haemangioendotheliomas may closely resemble malignant mesothelioma clinically and pathologically but, of the 92 pleural mesotheliomas tested, none showed expression of CD31, CD34, and Von Willebrand factor. Although all three cases had claimed exposure to asbestos, ferruginous bodies typical of asbestos were only seen by light microscopy in case 2, and only in this subject was the asbestos fibre content raised in comparison with the range seen in a non-exposed background population. The latent period in the pleural epithelioid haemangioendotheliomas ranged from 18 to 60 years. CONCLUSIONS: Endothelial differentiation does not appear to occur in mesothelioma and therefore should be clearly separated from it. No definite association between pleural epithelioid haemangioendothelioma and exposure to asbestos can be made from this small series but further investigation is warranted.

Interlaboratory comparison of methods To quantify microsclerotia of verticillium dahliae in soil

In a comparison of different methods for estimating Verticillium dahliae in soil, 14 soil samples were analyzed in a blinded fashion by 13 research groups in seven countries, using their preferred methods. One group analyzed only four samples. Twelve soil samples were naturally infested, and two had known numbers of microsclerotia of V. dahliae added to them. In addition, a control was included to determine whether transport had an effect on the results. Results differed considerably among the research groups. There was a 118-fold difference between the groups with the lowest and highest mean estimates. Results of the other groups were evenly distributed between these extremes. In general, methods based on plating dry soil samples gave higher numbers of V. dahliae than did plating of an aqueous soil suspension. Recovery of V. dahliae from samples with added microsclerotia varied from 0 to 59%. Most of the variability within each analysis was at the petri dish level. The results indicate the necessity to check the performance of detection assays regularly by comparing recoveries with other laboratories, using a common set of soil samples. We conclude that wet plating assays are less accurate than dry plating assays.

Myocardial ischaemia during tracheal extubation in patients after cardiac surgery: an observational study.

This study examines whether there is a temporal relationship between tracheal extubation and myocardial ischaemia in haemodynamically stable patients extubated within 6 h of cardiac surgery. Fifty-two patients were studied during three time periods: 1, from 2 h until 30 min before extubation (90 min); 2, from 30 min before until 30 min after extubation (60 min); 3, from 30 min until 2 h after extubation (90 min). Significant ST segment changes were defined as a reversible ST segment depression of 2 mm or greater or an elevation of 3 mm or greater from baseline, lasting for 1 min or more. Fourteen patients (26.9%) had ST segment changes. The ischaemic burden in periods 2 and 3 was increased compared with that in period 1; the mean (SD) was: period 1, 19.2 (18.8) min; period 2, 35.4 (24.9) min; period 3, 39.6 (24.5) min; however, the mean ST deviation (mm) did not change. ST segment changes were associated with an increased heart rate; they were not related to arterial pressure. We conclude that there is a temporal relationship between ST segment changes and tracheal extubation after cardiac surgery.

Revision of the 1990 working formulation for cardiac allograft rejection: the Sheffield experience.

OBJECTIVE: To audit the 1990 International Society for Heart and Lung Transplantation cardiac rejection criteria and to evaluate the impact on classification and clinical outcomes of a modification in which grade 2 is abolished and grades 1A and 1B are amalgamated into a single "grade 1." METHODS: 1652 heart biopsies were reviewed over a four year period. The initial 1348 biopsies (group 1), using the original 1990 criteria, were analysed in terms of diagnostic grade and compared with the 304 biopsies analysed with the modified scheme (group 2). Differences in grading with the 1990 scheme were compared between two groups (1.1 and 1.2) reflecting early and late experience with grading. Subsequently all the grade 2 and grade 1B biopsies were rescored in terms of the modified scheme. Clinical results in terms of actuarial patient survival at one year and freedom from 3A rejection were similarly audited. RESULTS: The relative ratios of potentially significant rejection (grade 3A, 3B, 4) remained constant over the entire study in groups 1.1, 1.2, and 2. A 50% reduction in grade 2 biopsy reporting was noted comparing early and late parts of group 1. At subsequent review of the group 1 grade 2 biopsies, 97% could be reassigned to grades 0 or 1 in the modified scheme, with the majority of these diagnoses reflecting Quility effect/biopsy site reactions. Two cases (3%) of the 77 grade 2 biopsies were regraded as grade 3A rejection, with both occurring within three months of transplantation. None of the grade 1B biopsies had high grade cardiac rejection on review, most of these biopsies similarly showing pronounced Quility effect and biopsy site reactions. Actuarial survival at one year rose from 86% to 90% during the study, with freedom from 3A rejection remaining unchanged at 80%. CONCLUSIONS: The original working formulation produces consistent grading except at grade 2, which is judged to be a misnomer resulting from Quility effect and other non-rejection phenomena. While acceptable standardisation can be achieved with the 1990 scheme, the modified scheme has advantages in that it appears to encourage clear discrimination between significant and non-significant cardiac rejection. Overall, elimination of grade 2 did not produce an increase in higher grades of cardiac rejection, and thus the value of this diagnostic grade is questioned.

Mechanisms of bone loss after cardiac transplantation.

To determine the mechanism of bone loss after cardiac transplantation (CTX), we studied 50 men 0.5-47 months after CTX (ages 18-64 years) who received prednisolone and cyclosporin to prevent rejection, and 40 healthy men as controls (ages 20-70 years). We measured bone mineral density (BMD) using dual-energy X-ray absorptiometry (DXA), bone resorption using urinary cross-linked N-terminal telopepides of type I collagen (NTx), and bone formation using osteocalcin (BGP) and bone alkaline phosphatase (BAP). The results from the controls were used to calculate z scores. BMD was significantly decreased at the lumbar spine, femoral neck, and total body, and bone turnover was significantly increased as assessed by NTx/creatinine, BGP, and BAP as compared with controls (p < 0.01 for all measurements). To evaluate the cause of the increased bone turnover we measured serum parathyroid hormone (PTH) by IRMA, and this was also elevated (p < 0.001). There was a significant correlation between serum PTH and BGP (r = 0.58, p < 0.01). To evaluate the cause of the increase in PTH, we measured serum calcium and it was decreased (p < 0.001), serum phosphorus was increased (p < 0.001), serum creatinine was increased (p < 0.001), and serum 1,25-dihydroxyvitamin D3 [1,25(OH)2D, RIA] was decreased (p = 0.03). Serum PTH correlated weakly with serum calcium (r = -0.41, p < 0.003) and with serum creatinine (r = 0.35, p = 0.01). There was a weak, but significant, correlation between serum creatinine and 1,25(OH)2D3 (r = 0.33, p = 0.03). Serum levels of testosterone and dehydroapiandrosterone sulfate were decreased after CTX but did not correlate with any other parameters. There was a weak negative correlation between prednisolone daily dose and serum BGP level (r = 0.29, p = 0.06) in those patients whose prednisolone current dose was >7.5 mg/day. We conclude that: (1) the low BMD found after CTX is associated with increased bone turnover which results, in turn, from renal impairment; (2) prednisolone is involved in rapid bone loss, whereas mild secondary hyperparathyroidism may be a major contributor to disorder of bone remodeling after this rapid loss; and (3) decreased androgen levels may not be a major factor resulting in bone loss in men after CTX.

Polyhydroxyalkanoate production in Rhodobacter capsulatus: genes, mutants, expression, and physiology.

Like many other prokaryotes, the photosynthetic bacterium Rhodobacter capsulatus produces high levels of polyhydroxyalkanoates (PHAs) when a suitable carbon source is available. The three genes that are traditionally considered to be necessary in the PHA biosynthetic pathway, phaA (beta-ketothiolase), phaB (acetoacetylcoenzyme A reductase), and phaC (PHA synthase), were cloned from Rhodobacter capsulatus. In R. capsulatus, the phaAB genes are not linked to the phaC gene. Translational beta-galactosidase fusions to phaA and phaC were constructed and recombined into the chromosome. Both phaC and phaA were constitutively expressed regardless of whether PHA production was induced, suggesting that control is posttranslational at the enzymatic level. Consistent with this conclusion, it was shown that the R. capsulatus transcriptional nitrogen-sensing circuits were not involved in PHA synthesis. The doubling times of R. capsulatus transcriptional nitrogen-sensing circuits were not involved in PHA synthesis. The doubling times of R. capsulatus grown on numerous carbon sources were determined, indicating that this bacterium grows on C2 to C12 fatty acids. Grown on acetone, caproate, or heptanoate, wild-type R. capsulatus produced high levels of PHAs. Although a phaC deletion strain was unable to synthesize PHAs on any carbon source, phaA and phaAB deletion strains were able to produce PHAs, indicating that alternative routes for the synthesis of substrates for the synthase are present. The nutritional versatility and bioenergetic versatility of R. capsulatus, coupled with its ability to produce large amounts of PHAs and its genetic tractability, make it an attractive model for the study of PHA production.

A comparison of the cytology of endomyocardial biopsy washings from heart transplants with biopsy histologic study and peripheral blood lymphocyte counts.

Cytospin preparations of endomyocardial biopsy washings were examined on 117 occasions from 13 heart transplant recipients and categorized according to the pattern of cell types observed. Twenty-nine percent of samples were acellular, a further 10% too bloodstained for analysis, and 61% were cellular. Eight lymphocytic samples were found and in all cases there was at least grade 1B rejection (four grade 1B, three grade 2, and one grade 3A) on histologic study. However, histologic study showed at least 1B rejection in 48% of cases when cytospins showed mixed inflammatory cells, 33% of cases when cytospins were histiocytic and in 35% when cytospins were bloodstained or acellular. Furthermore 16 of these rejection episodes with nonlymphocytic cytospins were grade 2. Although the recovery of a lymphocytic cytospin was specific for rejection, the sensitivity of the test was poor. Even when the sample is adequate, this method of biopsy washings will predict only one third of cases of significant acute rejection (grade 2 or worse). The large proportion of unsuitable samples also severely limits the utility of endomyocardial biopsy washings for the diagnosis of rejection. Histiocytic cytospins were seen in 63% of samples when previous biopsy sites were reported on histologic study and also in all three samples when histologic study showed ischemic injury. A mixed inflammatory cell pattern was seen to a lesser extent (31% of samples) in relation to previous biopsy sites. High peripheral blood lymphocyte counts were found when endomyocardial biopsy washings were lymphocytic or mixed inflammatory and also when histologic study showed endocardial lymphocytic infiltration (Quilty effect).

Distension reduces the vasoreactivity of the internal mammary artery.

Although the vasoreactivity of internal mammary artery grafts is beneficial in the long term, after mobilisation, vasospasm reduces flow through the vessel. This may be overcome and flow improved by distension. To assess the effects of distension on the vasoreactivity of the artery we have measured changes in isometric tension in rings of distended and undistended human internal mammary artery. For an equivalent wall tension, the diameter of the distended artery was 1922 microns (CL 1858 to 1986) and undistended 1684 microns (CL 1628 to 1739), (P < 0.001). In response to 25 mM potassium the increase in isometric tension, as a percent of resting tension, was 35% (CL 31 to 39) in undistended and 5% (CL 3 to 6) in distended segments (P < 0.001), with 10 microM noradrenaline increases were 57% (CL 47 to 66) and 3% (CL 2 to 5), respectively (P < 0.001). The reduction in developed tension in segments contracted with potassium and relaxed with 1 microM acetylcholine was 65% (CL 47 to 83) in undistended, and 15% (CL -1 to 32) in distended (P < 0.01). With 10 microM glyceryl trinitrate relaxation was 96% (CL 87 to 105) and 17% (CL -9 to 43), respectively (P < 0.01). Similarly, after contraction by noradrenaline, with acetylcholine, undistended segments relaxed by 50% (CL 44 to 55) and distended by 14% (CL 8 to 21) (P < 0.01), with glyceryl trinitrate relaxation was 90% (CL 80 to 99) and 7% (CL -4 to 19), respectively (P < 0.001). Distension produces a profound reduction in vasoreactivity of the internal mammary artery which is not due to endothelial damage alone.

Omission of aspirin in patients following coronary artery bypass graft surgery.

Graft patency is a major factor contributing to the long-term results of coronary artery bypass graft (CABG) surgery. The systematic overview of the Antiplatelet Trialists' Collaboration provides unequivocal evidence that antiplatelet therapy reduces by nearly one-half the odds of coronary graft occlusion following CABG. We retrospectively reviewed patients undergoing CABG during 1993 at the Cardiothoracic Unit, Northern General Hospital, to determine the incidence of, and indications for, aspirin omission following CABG: 462 patients with isolated CABG, 75 patients with a combined CABG and a heart valve procedure and 21 patients with a combined CABG and other non-valve procedure. Thirty-six patients (7.5%) with isolated CABG and CABG combined with a non-valve procedure were not prescribed aspirin. The reasons for aspirin omission were categorized into three groups depending on whether omission was fully justified (group 1), possibly justified (group 2) or unjustified (group 3). Twenty-one patients were in groups 2 and 3, nine of whom were started on aspirin 2-6 weeks after discharge without any ill effect. Forty-two patients were discharged from hospital on a three month course of warfarin. Four months later four patients had died, 24 had changed to aspirin, 10 were still on warfarin and four were on neither drug. Aspirin was sometimes omitted without clear indications. Better provisions for supervision should be made by either the General Practitioner or Hospital Practitioner during the change-over period from oral anticoagulation to antiplatelet therapy in patients on a short course of warfarin.

Recruitment of primary care physicians to care for patients with human immunodeficiency virus infection in a large northwestern county.

BACKGROUND: We evaluated an initiative to recruit and to educate physicians to care for persons with human immunodeficiency virus (HIV) infection in King County, Washington, and to refer patients to them through a centralized telephone referral service (the acquired immunodeficiency syndrome [AIDS]/HIV Care Access Project). METHODS: Six physicians trained in AIDS care recruited primary care physicians in clinics throughout King County; the physician cohort was monitored for behavior in accepting referrals during the ensuing year. RESULTS: Of 250 primary care physicians contacted initially, 79 of 120 who met with AIDS-trained physicians were willing to accept patient referrals. Willingness was not related significantly to age, sex, years in practice, or specialty, but was related to level of experience with HIV/AIDS care and current practice. The recruitment initiative increased the physicians available to the telephone referral service by 93% (from 85 to 164). More physicians (41) joined the referral service in the ensuing year, during which 647 patient referrals were made to these 205 physicians (median referral rate of one patient per quarter). Four physicians requested cessation of referrals, however, two later asked for referrals to continue. CONCLUSION: The recruitment initiative was successful in increasing the number of primary care physicians available to accept patients with HIV infection into their practices (thereby reducing the burden of HIV referrals on a small pool of providers), and in establishing a county-wide telephone service to coordinate these referrals. The initiative was self-sustaining, with an ongoing influx of new providers willing to take referrals.

Use of milrinone in cardiac surgical patients.

Milrinone is shown in 10 patients to be a valuable pharmacological bridge to heart transplantation; it can stabilize and improve decompensated chronic heart failure (CHF) in cases where the response to beta-agonists is inadequate. One patient who had suffered an acute myocardial infarction with heart failure resistant to vasodilators, beta-agonists, and balloon counterpulsation was stabilized with milrinone for 21 days. He was then maintained on ACE inhibitors until heart transplantation 3 months later. The other nine patients with severe decompensated CHF were stabilized on milrinone for between 11 and 51 days. Seven of them received a donor heart. Two patients died of bacteremic shock and terminal heart failure before a suitable organ could be found (31 and 51 days). All patients were clinically improved within 48 hours of the addition of IV milrinone to their therapy. In 55 patients following cardiac surgery, the efficacy and safety of milrinone in the treatment of low cardiac output states is demonstrated. Milrinone has a useful role in the management of patients with circulatory failure both before and after cardiac surgery, and this paper reviews the relevant current literature.

Pathology of surgically excised primary cardiac tumors.

Between 1957 and March 1991, 106 patients with 110 neoplasms that originated in the heart were treated surgically at the Mayo Clinic and had pathologic material available for review. The study group consisted of 39 male and 67 female patients, who ranged in age from 2 to 80 years. Benign atrial myxomas (64 in the left atrium and 16 in the right atrium) were the most commonly encountered neoplasm. The other benign tumors were nine fibromas, five lipomatous tumors, seven valvular fibroelastic papillomas, and one cardiac hamartoma (so-called oncocytic cardiomyopathy). In addition, eight patients had a primary cardiac malignant lesion: angiosarcoma, leiomyosarcoma, and malignant fibrous histiocytoma in two patients each and sarcoma (not otherwise specified) and osteogenic sarcoma in one patient each. The angiosarcomas originated in the right atrium, and the other malignant tumors originated in the left atrium. The histologic feature that most frequently predicted an adverse clinical outcome was the presence of mitotic figures, although highly cellular tumors and those with necrosis also tended to have a malignant course.