Delirium Due to Potentially Avoidable Hospitalizations Among Older Adults

BACKGROUND

Delirium is a common complication during acute care hospitalizations in older adults. A substantial percentage of admissions are for ambulatory care-sensitive conditions (ACSCs) or potentially avoidable hospitalizations-conditions that might be treated early in the outpatient setting to prevent hospitalization and hospital complications.

METHODS

This retrospective cross-sectional study examined rates of delirium among older adults hospitalized for ACSCs. Participants were 39 933 older adults ≥65 years of age admitted from January 1, 2015 to December 31, 2019 to general inpatient units and ICUs of a large Southeastern academic medical center. Delirium was defined as a score ≥ 2 on the Nursing Delirium Screening Scale or positive on the Confusion Assessment Method for the Intensive Care Unit during admission, and ACSCs were identified from the primary admission diagnosis using standardized definitions. Generalized linear mixed models were used to examine the association between ACSCs and delirium, compared with admissions for non-ACSC diagnoses, adjusting for covariates and repeated observations for individuals with multiple admissions.

RESULTS

Delirium occurred in 15.6% of admissions for older adults. Rates were lower for ACSC admissions versus admissions for other conditions (13.9% vs 15.8%, p < .001). Older age and higher comorbidity were significant predictors of the development of delirium.

CONCLUSIONS

Rates of delirium among older adults hospitalized for ACSCs were lower than rates for non-ACSC hospitalization but still substantial. Optimizing the treatment of ACSCs in the outpatient setting is an important goal not only for reducing hospitalizations but also for reducing risks for hospital-associated complications such as delirium.

Annotation of Opioid Use Disorder Entity Modifiers in Clinical Text

Natural Language Processing can be used to identify opioid use disorder in patients from clinical text1. We annotate a corpus of clinical text for mentions of concepts associated with unhealthy use of opiates including concept modifiers such as negation, subject, uncertainty, relation to document time and illicit use.

Hospital-associated disability due to avoidable hospitalizations among older adults

BACKGROUND

Hospital-associated disability (HAD) is a common complication during the course of acute care hospitalizations in older adults. Many admissions are for ambulatory care sensitive conditions (ACSCs), considered potentially avoidable hospitalizations-conditions that might be treated in outpatient settings to prevent hospitalization and HAD. We compared the incidence of HAD between older adults hospitalized for ACSCs versus those hospitalized for other diagnoses.

METHODS

We conducted a retrospective cohort study in inpatient (non-ICU) medical and surgical units of a large southeastern regional academic medical center. Participants were 38,960 older adults ≥ 65 years of age admitted from January 1, 2015, to December 31, 2019. The primary outcome was HAD, defined as decline on the Katz Activities of Daily Living (ADL) scale from hospital admission to discharge. We used generalized linear mixed models to examine differences in HAD between hospitalizations with a primary diagnosis for an ACSC using standard definitions versus primary diagnosis for other conditions, adjusting for covariates and repeated observations for individuals with multiple hospitalizations.

RESULTS

We found that 10% of older adults were admitted for an ACSC, with rates of HAD in those admitted for ACSCs lower than those admitted for other conditions (16% vs. 20.7%, p < 0.001). Age, comorbidity, admission functional status, and admission cognitive impairment were significant predictors for development of HAD. ACSC admissions to medical and medical/surgical services had lower odds of HAD compared with admissions for other conditions, with no significant differences between ACSC and non-ACSC admissions to surgical services.

CONCLUSIONS

Rates of HAD among older adults hospitalized for ACSCs are substantial, though lower than rates of HAD with hospitalization for other conditions, reflecting that acute care hospitalization is not a benign event in this population. Treatment of ACSCs in the outpatient setting could be an important component of efforts to reduce HAD.

Delirium Mediates Incidence of Hospital-Associated Disability Among Older Adults

OBJECTIVE

To examine whether delirium predicts occurrence of hospital-associated disability (HAD), or functional decline after admission, among hospitalized older adults.

DESIGN

Retrospective cross-sectional study.

SETTING AND PARTICIPANTS

General inpatient (non-ICU) units of a large regional Southeastern US academic medical center, involving 33,111 older adults ≥65 years of age admitted from January 1, 2015, to December 31, 2019.

METHODS

Delirium was defined as a score ≥2 on the Nursing Delirium Screening Scale (NuDESC) during hospital admission. HAD was defined as a decline on the Katz Activities of Daily Living (ADL) scale from hospital admission to discharge. Generalized linear mixed models were used to examine the association between delirium and HAD, adjusting for covariates and repeated observations with multiple admissions. We performed multivariate and mediation analyses to examine strength and direction of association between delirium and HAD.

RESULTS

One-fifth (21.6%) of older adults developed HAD during hospitalization and experienced higher delirium rates compared to those not developing HAD (24.3% vs 14.3%, P < .001). Age, presence of delirium, Elixhauser Comorbidity Score, admission cognitive status, admission ADL function, and length of stay were associated (all P < .001) with incident HAD. Mediational analyses found 46.7% of the effect of dementia and 16.7% of the effect of comorbidity was due to delirium (P < .001).

CONCLUSIONS AND IMPLICATIONS

Delirium significantly increased the likelihood of HAD within a multivariate predictor model that included comorbidity, demographics, and length of stay. For dementia and comorbidity, mediation analysis showed a significant portion of their effect attributable to delirium. Overall, these findings suggest that reducing delirium rates may diminish HAD rates.

Identification of Gout Flares in Chief Complaint Text Using Natural Language Processing

Many patients with gout flares treated in the Emergency Department (ED) often do not receive optimal continuity of care after an ED visit. Thus, developing methods to identify patients with gout flares in the ED and referring them to appropriate outpatient gout care is required. While Natural Language Processing (NLP) has been used to detect gout flares retrospectively, it is much more challenging to identify patients prospectively during an ED visit where documentation is usually minimal. We annotate a corpus of ED triage nurse chief complaint notes for the presence of gout flares and implement a simple algorithm for gout flare ED alerts. We show that the chief complaint alone has strong predictive power for gout flares. We make available a de-identified version of this corpus annotated for gout mentions, which is to our knowledge the first free text chief complaint clinical corpus available.

Operator and Potential Exposure to Hydrogen Sulfide: A Study of the British Columbia Dairy Industry

Hydrogen Sulfide (H2S) is produced in manure storage facilities and released during manure agitation. Exposure to this gas presents health risks to workers at daily exposure of greater than 10 parts per million (ppm). Exposure levels on BC dairy farms are unknown. The aim of this study was to document peak H2S exposure levels to operators and bystanders during manure agitation on British Columbia dairy farms to determine if action levels were exceeded. Farms were evaluated at two time points during manure agitation. Both operator exposure and potential exposure sampling were undertaken. Peak hydrogen sulfide levels were measured and categorized as greater than or less than the ceiling level (10 ppm) and action level (5 ppm). Associations between H2S levels above the ceiling level and farm factors were assessed. Measures were recorded at 43 dairy farms with 91 total measures recorded. Action levels were exceeded in 30% of operator measures and 64% of potential exposure measures while 20% of operator and 53% of potential peak H2S measures exceeded 10 ppm. Manure storage facilities were evenly distributed between indoor and outdoor locations with under-barn (43%) and outdoor storage (47%) most common. Sawdust was the most prominent bedding type (65%). Tractor operated propeller was the most common type of agitation equipment (62%). Manure temperature remained a significant predictor in the multivariate model for operator peak exposure. Exposure to H2S above the action level commonly occurs on BC Dairy farms. Given that Worksafe BC requires exposure control plans for H2S levels above 5 ppm, and that on dairy farms, measures of operator and potential H2S exposures were recorded above these levels, best practices to reduce potential H2S exposure are necessary to reduce possible operator and bystander exposure.

Effect of small molecule supplements during in vitro culture of mouse zygotes and parthenogenetic embryos on hypoblast formation and stem cell derivation

BACKGROUND

Small molecule inhibitors are organic components that modulate signalling pathways and have the ability to change the differentiation state of cells. They have been used to increase the efficiency of induced pluripotent stem cell generation and to support stem cell derivation and culture. In this study, we aimed to evaluate the effects of small molecules on the development of mouse zygotes and parthenogenetic embryos.

METHODS AND RESULTS

Three inhibitors (SC-1, PD0325901 and BIO) were added to the culture medium from the 2-cell stage onwards. We have observed that addition of an inhibitor of the fibroblast growth factor (FGF) pathway (SC-1 or PD0325901) compromises the segregation of hypoblast from the inner cell mass (ICM). Given no difference was observed in size of the ICM, but more epiblast cells were found in these embryos, we can conclude that this is caused by redirection of all ICM cells to the epiblast. We also determined the consequences of reduced hypoblast and increased epiblast formation on stem cell derivation efficiency. No significant difference was found between derivation rates from treated embryos as compared to controls. However, only under 2i + ROCKi conditions, stem cells could be derived with an efficiency of more than 90%. Addition of BIO, an activator of the WNT pathway, did not have any effects on hypoblast development or stem cell derivation.

CONCLUSION

We have demonstrated that FGF signalling is crucial for hypoblast generation and small molecules can be efficiently used to inhibit this process both in zygotes and parthenogenetic embryos.

The influence of patient and cohort parameters on the incidence and developmental potential of embryos with poor quality traits for use in human embryonic stem cell derivation

BACKGROUND

Human embryonic stem cells (hESCs) are most commonly derived from the inner cell mass (ICM) of blastocyst stage embryos. While the majority of hESC lines originate from good-quality embryos donated after cryogenic storage, poor-quality embryos (PQEs) not suitable for clinical use have also been shown to generate hESC. This provides a newfound function for embryos that would otherwise be discarded following IVF or ICSI. Owing to their lack of clinical importance, however, data on the poorest embryos in a cohort go largely unreported in the literature. It is therefore of interest to better understand the availability of PQEs from IVF/ICSI cycles and to determine their ability to develop into blastocysts with good-quality ICMs for use in hESC derivation. In this study, we investigate the influence of patient parameters and embryo cohort on PQE incidence, blastocyst development, ICM quality and successful hESC derivation from donated PQEs.

METHODS

PQEs from 736 patient cycles that did not meet our clinical criteria for transfer or cryopreservation were cultured until Day 6 of development and assessed for blastocyst formation and ICM quality. A subset of blastocysts with good-quality ICMs were then used for hESC derivation attempts. Anonymous patient data such as maternal age, embryo history and cohort parameters were then retrospectively compiled and analysed.

RESULTS

PQEs made up 46.8% of two pronucleate embryos created from IVF/ICSI. Including embryos with abnormal fertilization, a mean of 3.6 ± 2.8 embryos were donated per cycle with 32.6% developing to the blastocyst stage. Good-quality ICM were produced in 13.9% of PQEs cultured. Of good-quality ICM, 15.4% of those used in hESC derivation attempts resulted in a novel line. The PQEs that originated from older patients (>37 year) or from cycles that did not result in pregnancy had significantly diminished blastocyst development and ICM quality. Maternal age was also shown to further influence the ability of good-quality ICMs to generate hESC.

CONCLUSIONS

PQEs are an abundant source of embryos capable of developing to blastocysts with good-quality ICMs and subsequently generating novel hESC. We have shown that prognostic variables used to predict IVF/ICSI outcome can also help predict which PQEs have the best hESC developmental potential. Owing to the diversity of PQE origin, experiments designed to compare hESC derivation techniques or efficiency using PQEs should consider clinical IVF/ICSI parameters to establish groups with equal developmental competence. Additional investigation is needed to determine if these results are applicable to hESC derivation using good-quality embryos.

Morphologic parameters of early cleavage-stage embryos that correlate with fetal development and delivery: prospective and applied data for increased pregnancy rates

BACKGROUND

Many different embryo selection criteria have been used in assisted reproductive technologies (ART), but there are no published prospective studies to ascertain their usefulness in predicting implantation.

METHODS

In a prospective trial, 20 early scoring parameters previously reported to influence clinical outcome were collected, but embryos were selected for transfer by current laboratory protocols; day 1 pronuclear (PN) (Z) score combined with day 3 or 5 morphology. Data points for each oocyte/embryo were scored independently and tracked individually. Data were analysed retrospectively for parameters most likely to result in a positive pregnancy test, fetal heartbeat (FHB) and delivery.

RESULTS

Results indicated that day 1 PN morphology and nucleolar precursor body (NPB) ratio, day 2 cell number, blastomere symmetry and nucleation and the ability to cleave from day 2 to day 3 were the six most significant factors in fetal development. This outcome was then applied prospectively over 8 months. The implantation rate (IR) and clinical pregnancy rate (CPR) increased in each age group, and the number of embryos used decreased.

CONCLUSION

In conclusion, early parameters that include PN morphology, number and ratio of NPBs per nucleus and the day 2 morphology of cleaving embryos are stronger positive predictors of implantation than day 3 morphology or the ability to achieve the blastocyst stage of development. Parameters that were most consistently correlated with no delivery were lack of PN symmetry, day 2 multinucleation and uneven cell size. Day 3 and day 5 parameters were not significant compared with the combination of early parameters.

The environmental response of Middle Ordovician large organic walled microfossils from the Goldwyer and Nita Formations, Canning Basin, Western Australia

Middle Ordovician large organic walled microfossils (chitinozoans, scolecodonts, hydrozoans and foraminiferal linings) were recovered from the upper Goldwyer and lower Nita formations, Canning Basin, Western Australia, from three cores (WMC Santalum 1A, Kunzea 1 and Acacia 2). Petrophysical logs of these cores reveal an overall upward shallowing supersequence, overprinted by numerous transgression/regression couplets that can be correlated over 100km.Analysis of the abundance of the microfossils with respect to the gamma log signatures reveals that both chitinozoan abundance and diversity decrease as water depth shallows; however, the opposite is not always true and other factors probably intervene. Scolecodonts show an increase in abundance in transgressions, while hydrozoans and foraminiferal linings show no consistent response to trangressive or regressive phases. Cyathochitina hunderumensis tends to dominate chitinozoan assemblages where there is a transgression, while species of Belonechitina replace Cy. hunderumensis in regressive phases.

Loss of heterozygosity at 1p36 predicts poor prognosis in gastrointestinal stromal/smooth muscle tumors

Gastrointestinal stromal/smooth muscle tumors are uncommon neoplasms for which current criteria for diagnosing malignancy (size and mitotic index) sometimes fail to predict outcome. Cytogenetic studies reveal frequent chromosome 1 abnormalities in these tumors, but significant underlying molecular changes have not been elucidated, and their significance is unknown. DNA was obtained from the formalin-fixed, paraffin-embedded tissue of 80 gastrointestinal stromal/smooth muscle tumors. Tumors were topographically microdissected from surrounding normal tissue; microsatellite markers from tumor and normal tissue were amplified by PCR in the regions of chromosome 1p36 (D1S199, D1S228, D1S450, D1S214, D1S243), 1p12 (D1S418),1p13 (D1S252, D1S514), and 1q32(D1S103). The presence or absence of heterozygosity for each case was mapped at each informative marker. Relationships among loss of heterozygosity (LOH), tumor size, mitotic index, and survival were investigated using correlation analysis, Kaplan-Meier plots, and the Cox model. LOH at 1p36 was found in 24 of 80 cases, suggesting the possibility of a tumor suppressor gene at 1 p36 near the site of a suspected neuroblastoma tumor suppressor gene. Patients whose tumors demonstrated LOH at 1 p36 had significantly shorter survival (p = 0.017) than those whose tumors did not. LOH at 1 p36 retained independent prognostic significance in a multivariate model that included KIT mutation status and tumor size; the mitotic index, however, did not retain independent significance in such a model. LOH was observed at 1 p12-1p13 (most frequently at 1p13.3) in 19 of 80 cases, but loss of heterozygosity at this site did not influence survival. No LOH was observed near 1q32. These findings provide strong evidence for a prognostically significant tumor suppressor gene in the region of chromosome 1p36.3.

Sensitivity of cross-reacting antihuman antibodies in formalin-fixed porcine skin: including antibodies to proliferation antigens and cytokeratins with specificity in the skin

Although no animal is a perfect skin model for the study of toxicological and therapeutic agents, structurally the pig may be superior to even non-human primates. Because our work involves effects of toxicological and therapeutic agents on the skin, we wanted to identify stains which may prove useful as well as determine cross-reactivity of some newer antihuman antibodies. We performed a battery of formalin-fixed skin from weanling pigs and minipigs. The battery of antibodies included LCA, CD3, OPD-4, CD34, UCHL-1, L-26, KP-1, MAC-387, Factor XIIIa, Leu-7, S-100 protein, HMB-45, GFAP, synaptophysin, neurofilament protein, ubiquitin, vimentin, type IV collagen, laminin, fibronectin, Factor VIII related antigen, Desmin-M, smooth muscle actin, cytokeratin 7, cytokeratin 20, AEI/AE3, CAM 5.2, EMA, GCDFP, Ki-67, and PCNA. Immunohistochemical stains for CD3, Leu-7, S-100 protein, type IV collagen, laminin, Factor VIII related antigen, GFAP, synaptophysin, neurofilament protein, ubiquitin, smooth muscle actin, vimentin, Desmin-M, cytokeratin 7, cytokeratin 20, AE1/AE3, CAM 5.2, Ki-67 and PCNA showed consistent cross-reactivity. In formalin-fixed tissue, only antibodies to lymphoreticular cells showed poor cross-reactivity. A high percentage of the remaining antibodies did show good cross-reactivity but with some interesting similarities and differences in specificity.

Evaluation of cross-reacting anti-human antibodies in the euthymic hairless guinea pig model (HGP) suggests that the HGP may be a model for the study of proliferative skin disease

Animal models have an important role in cutaneous research. The guinea pig has proven to be a useful model in a wide spectrum of these cutaneous studies; however, its usefulness is often compromised by the need for depilation. A euthymic hairless guinea pig (HGP) model avoids the problems associated with depilation. Morphologically, as in human skin, these animals have a multi-cell-layer epidermis. Proliferation kinetic studies, as well as documentation of the degree of immunologic cross-reactivity between available antibodies to human cutaneous antigens, could extend the usefulness of this animal model. We performed a battery of anti-human antibodies on formalin fixed tissue, to a variety of antigens present within the skin and on inflammatory cells. These included CD3, UCHL-1, OPD4, L-26, KP-1, Factor XIIIa, S-100 protein, cytokeratin (AE1, AE3 and CK1), CAM 5.2, vimentin, CD 34, Factor VIII, fibronectin, SM actin, collagen IV, laminin, Bcl-2, p53, Ki-67, and PCNA. Cross-reacting antibodies included: CD3, S-100 protein, cytokeratin (AE1, AE3 and CK1), vimentin, Factor VIII, SM actin, collagen IV, p53, Ki-67, and PCNA. Although this battery of antibodies is limited, the markedly increased staining of Ki-67 and PCNA within keratinocytes in the epidermis as compared to normal human skin reflects a high proliferative rate. In addition, positive staining for p53, Ki-67, and PCNA may be useful in studying effects on cell cycle kinetics and apoptosis.

Pulmonary blastomas

Pulmonary blastoma is a rare lung tumor composed of immature mesenchyme and/or epithelium that morphologically mimics embryonal pulmonary structure. The prognosis of these tumors is poor, and the clinical course is not readily predicted from histologic appearance. In this report, the clinical, gross, microscopic, and immunopathologic features of 52 cases are described, and prognostically important correlates are determined. Twenty-eight patients were women, and 24 were men. There was a unimodal age peak in the fourth decade; only two patients were younger than 10 years old, and both had biphasic blastomas. Forty-one percent of patients were asymptomatic. Chest radiography typically showed a peripheral or midlung mass without predilection for any lobe. Microscopically, tumors could be divided into two classes: those composed solely of malignant glands of embryonal appearance (well-differentiated fetal adenocarcinomas [WDFA], 28 cases) and those with a biphasic appearance (24 cases). The malignant epithelium contained cytokeratin, carcinoembryonic antigen, milk fat globulin, and often chromogranin; vimentin, actin, and less frequently desmin and myoglobin were present in malignant stromal cells. More often WDFA was a smaller tumor (less than 5 cm) than biphasic tumors (P less than or equal to 0.001). It was more likely to be asymptomatic (P less than or equal to 0.001), and it was less likely to show pleural effusion by chest radiography (P less than or equal to 0.01) or giant or bizarre tumor cells (P less than or equal to 0.001) or frequent (greater than or equal to 30 mitoses/10 high-power fields) mitoses in the microscopic sections (P less than or equal to 0.01). Only 14% of patients with WDFA died of their tumor; 52% of patients with biphasic tumors died (mean follow-up, 97 months and 49 months, respectively). For patients with WDFA, the presence of thoracic adenopathy by chest radiography (P less than or equal to 0.001) and metastasis at initial presentation (P less than or equal to 0.001), followed by tumor recurrence (P less than or equal to 0.01), were the factors most highly correlated with poor prognosis. For patients with biphasic tumors, tumor recurrence (P less than or equal to 0.001) was the most significant indicator of poor prognosis, followed by metastasis at initial presentation (P less than or equal to 0.05) and gross size of the tumor (greater than or equal to 5 cm) (P less than or equal to 0.05). These findings support the idea that histologic class and gross and clinical findings can be of prognostic value in pulmonary blastoma.

Pulmonary blastomas

Pulmonary blastoma is a rare lung tumor composed of immature mesenchyme and/or epithelium that morphologically mimics embryonal pulmonary structure. The prognosis of these tumors is poor, and the clinical course is not readily predicted from histologic appearance. In this report, the clinical, gross, microscopic, and immunopathologic features of 52 cases are described, and prognostically important correlates are determined. Twenty-eight patients were women, and 24 were men. There was a unimodal age peak in the fourth decade; only two patients were younger than 10 years old, and both had biphasic blastomas. Forty-one percent of patients were asymptomatic. Chest radiography typically showed a peripheral or midlung mass without predilection for any lobe. Microscopically, tumors could be divided into two classes: those composed solely of malignant glands of embryonal appearance (well-differentiated fetal adenocarcinomas [WDFA], 28 cases) and those with a biphasic appearance (24 cases). The malignant epithelium contained cytokeratin, carcinoembryonic antigen, milk fat globulin, and often chromogranin; vimentin, actin, and less frequently desmin and myoglobin were present in malignant stromal cells. More often WDFA was a smaller tumor (less than 5 cm) than biphasic tumors (P less than or equal to 0.001). It was more likely to be asymptomatic (P less than or equal to 0.001), and it was less likely to show pleural effusion by chest radiography (P less than or equal to 0.01) or giant or bizarre tumor cells (P less than or equal to 0.001) or frequent (greater than or equal to 30 mitoses/10 high-power fields) mitoses in the microscopic sections (P less than or equal to 0.01). Only 14% of patients with WDFA died of their tumor; 52% of patients with biphasic tumors died (mean follow-up, 97 months and 49 months, respectively). For patients with WDFA, the presence of thoracic adenopathy by chest radiography (P less than or equal to 0.001) and metastasis at initial presentation (P less than or equal to 0.001), followed by tumor recurrence (P less than or equal to 0.01), were the factors most highly correlated with poor prognosis. For patients with biphasic tumors, tumor recurrence (P less than or equal to 0.001) was the most significant indicator of poor prognosis, followed by metastasis at initial presentation (P less than or equal to 0.05) and gross size of the tumor (greater than or equal to 5 cm) (P less than or equal to 0.05). These findings support the idea that histologic class and gross and clinical findings can be of prognostic value in pulmonary blastoma.

The relationship between psychosocial factors and breast cancer: some unexpected results

A growing body of research suggests a link between psychosocial factors and breast cancer. Research in this area often contains methodological problems, however, such as small sample size, inadequate comparison groups, omission of important control variables, inclusion of only a few psychosocial variables, and failure to analyze moderating effects. To overcome these problems, the present study examined the link between breast cancer and multiple psychosocial variables (life events, coping, Type A behavior pattern, availability of social support) among 1,052 women with and without breast cancer. After controlling for history of breast cancer and age, we found very few significant relationships between psychosocial variables and breast cancer. Furthermore, the relationship between life events and breast cancer was not moderated by coping, Type A, or availability of social support. Methodological and substantive reasons for these findings are discussed.

Evaluation of single-drug and combination antifungal therapy in an experimental model of candidiasis in rabbits with prolonged neutropenia

We developed an experimental model of candidiasis in rabbits with prolonged neutropenia. Rabbits were made neutropenic with cytosine arabinoside (Ara-C) administered through an indwelling silastic catheter that had been surgically implanted in the external jugular vein. Neutropenia was sustained with intravenous Ara-C, and bacterial complications were prevented with parenteral ceftazidime plus ampicillin. Candidiasis was established by intravenously administering Candida albicans or Candida tropicalis (1-2 x 10(5) colony-forming units) and resulted in hepatic and splenic lesions that mimicked those associated with hepatosplenic candidiasis in humans. The kidney proved to be the site most refractory to eradication of Candida spp. and offered a target organ for assessing antifungal therapy. We evaluated amphotericin B, 5-flucytosine, ketoconazole, and rifampin, alone and in combination. Although each agent reduced the colony counts of Candida in the liver, spleen, and lung, the combination of amphotericin B and 5-flucytosine was the only regimen effective in eradicating renal candidiasis.

Prevalent myocarditis at necropsy in the acquired immunodeficiency syndrome

The prevalence of myocarditis was retrospectively evaluated in 71 consecutive necropsy patients who died from acquired immunodeficiency syndrome (AIDS) between 1982 and 1986. Myocarditis was found in 37 cases (52%). Biventricular dilation at necropsy was present in seven cases (10%) and was accompanied by myocarditis in each case; fatal congestive heart failure occurred in four of these seven cases. Although viral, protozoan, bacterial, fungal and mycobacterial opportunistic pathogens were present in myocardial sections of 7 of 37 myocarditis cases, the etiology of myocarditis in the majority of these patients with AIDS remained idiopathic. Thus, myocarditis is a frequent finding at necropsy in patients with AIDS and may contribute to the development of biventricular dilation.

Hepatosplenic candidiasis: wheels within wheels

Eight immunocompromised cancer patients with tissue-proved candidiasis underwent serial abdominal ultrasound (US) and computed tomography (CT). At US, four patterns of hepatic and splenic candidiasis were recognized, one of which the authors call a "wheels-within-wheels" pattern. In addition, periportal linear areas of increased attenuation, possibly calcified, were identified at follow-up, nonenhanced CT. Some abscesses were better seen on nonenhanced CT scans, while others became visible only with enhancement. Although lesions not seen at US were often seen at CT, the opposite was also true. In two cases, pathologic proof of candidiasis was established even when all imaging studies were normal. For maximum imaging sensitivity, patients should be studied with US and nonenhanced and enhanced CT. Even when both US and CT scans are negative, if there is a strong clinical suggestion of candidiasis, open biopsy is recommended.

Hepatic candidiasis in cancer patients: the evolving picture of the syndrome

Focal hepatosplenic candidiasis has been recognized with increasing frequency in recent years. We reviewed the cases of eight patients seen between 1982 and 1985, and information on 60 patients whose cases have been reported in the world literature. The characteristics of focal hepatosplenic candidiasis include persistent fever in a neutropenic patient whose leukocyte count is returning to normal, often coupled with abdominal pain; an elevated alkaline phosphatase level; and less commonly, rebound leukocytosis. The characteristic "bull's eye" lesions seen with hepatic ultrasound examination or computed tomography generally are not detectable until neutrophil recovery has occurred. Diagnosis can be established only by biopsy evidence of yeasts or pseudohyphae in the granulomatous lesions. Cultures are frequently negative, however, especially in patients who have been pretreated with antifungal agents. We review the evolving nature of hepatosplenic candidiasis, focusing on diagnosis and treatment.

Synthesis and evaluation of a miniature organic model of chymotrypsin

An artificial chymotrypsin, with all the features of the real chymotrypsin, namely a binding site (from cyclodextrin) attached to a catalytic site containing an imidazolyl group, a carboxylate group and a hydroxyl group, has been synthesized. This artificial chymotrypsin has a molecular weight of only 1,365 while the real enzyme has a molecular weight of 24,800. However, from preliminary measurements, both the real and artificial enzymes have approximately the same catalytic activity (both rate and binding constants).

Prosthetic valve endocarditis caused by group Ve-1 bacteria (Chromobacterium typhiflavum)

A case of fatal prosthetic valve endocarditis was caused by group Ve-1 bacteria. Bacteriological characteristics and antibiotic susceptibilities are presented, as well as a brief discussion of the isolates of the Ve-1 organism in Ontario.

Experimental evaluation of five liver-spleen specific CT contrast agents

We tested five experimental liver-spleen specific computed tomography (CT) contrast agents, all of which are aqueous emulsions of iodinated vegetable oils. These compounds were compared with ethiodized oil emulsion 13 (EOE-13) and with a 5% dextrose in water control. We evaluated three animal/dose level models with both histology and CT to determine the best screening method for compounds of this type. We compared a rat/high dose model, a rat/medium dose model, and a rabbit/low dose model; the best discrimination was seen with the rabbit/low dose model. Histology of liver, spleen, and lung did not correlate with the attenuation values obtained from CT. We conclude that use of CT and a rabbit/low dose model is superior for screening compounds of this type. Of the compounds tested, only one, an emulsion of ethyl monoiodostearate (compound 208E), approached the effectiveness of EOE-13.

Liposarcoma of the lower extremity

Twenty patients with primary liposarcoma of the lower extremity were treated over a 25-year period. The adequacy of the initial surgical procedure and histological grade of malignancy both influenced survival rates. In addition local recurrence was noted only in patients who had undergone "inadequate" initial excision. Inguinal lymph nodes were uninvolved by tumor in all cases. In general, patients with liposarcomas of myxoid and/or round cell type survived for long periods of time. However, even patients with myxoid lesions occasionally exhibited evidence of early blood-borne metastases. This study suggests an important relationship between an inadequate primary resection, local recurrence, and eventual retroperitoneal spread. In the majority of cases, this may have resulted from failure to control the primary distal extremity tumor, with subsequent contiguous spread of metastases into the ipsilateral retroperitoneal space. If feasible, radical soft part resection should be performed as the primary surgical therapy of these neoplasms. Tumors contiguous to the knee or ankle joint should be treated by primary amputation. Failure to control local disease may result in blood-borne dissemination or local spread along musculoaponeurotic planes to involve proximal groin or retroperitoneal space.