A randomized trial of povidone-iodine compared with iodine tincture for venipuncture site disinfection: effects on rates of blood culture contamination.

BACKGROUND: Contamination of blood cultures creates problems in their interpretation and unneeded resource utilization. Because skin flora comprise the major group of contaminant species, more effective skin disinfection at the venipuncture site could reduce contamination. SUBJECTS AND METHODS: We performed a randomized trial in adult inpatients at a tertiary care teaching hospital. Antecubital venipuncture sites were randomly disinfected with povidone-iodine or iodine tincture, and blood cultures (two bottles, 10 mL of blood) were drawn by professional phlebotomists. Scoring of contaminant species was restricted to skin flora. Hospital resource utilization was compared among patients with contaminated blood cultures and those with sterile blood cultures. RESULTS: Of the 3,851 blood cultures collected during the study, 120 (3.1%) were contaminated with skin flora. The contamination rate for blood cultures collected after povidone-iodine was 3.8% (74 of 1,947), compared with a rate of 2.4% (46 of 1,904, P = 0.01) after iodine tincture. The difference in mean total hospital costs for patients with contaminated blood cultures and those with sterile blood cultures was $4,100 (95% confidence interval: $740 to $7,400, P = 0.02). CONCLUSIONS: Iodine tincture is superior to povidone-iodine for venipuncture site antisepsis before blood culture sampling. Because of the high costs associated with contaminated blood cultures, hospitals should consider switching from povidone-iodine to iodine tincture. Reduction of the contamination rate may improve the quality of patient care and reduce hospital costs.

Primary pulmonary botryomycosis: case report and review.

Botryomycosis is an uncommon bacterial disease characterized by the microscopic formation of eosinophilic granules that resemble those of infection by Actinomyces species. The diagnosis of botryomycosis can be made when microscopic inspection and culture of the granules reveal gram-positive cocci or gram-negative bacilli. Botryomycosis is caused by common bacterial pathogens including Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa, yet the host and microbial factors that contribute to the pathobiology remain unknown. Pulmonary botryomycosis can resemble actinomycosis, tuberculosis, or invasive carcinoma by causing a mass lesion with constitutional symptoms. Radiographically, it invades bone and disrupts tissue planes. Successful treatment often requires a combination of both surgical debridement and long-term antimicrobial therapy. We report a case of primary pulmonary botryomycosis and review the literature on this unusual infectious process.

High frequency of pseudobacteremia at a university hospital.

A prospective survey of all positive blood cultures was performed during a 6-month period at a 390-bed, tertiary-care teaching hospital in St Louis, Missouri. Data were collected from the clinical microbiology laboratory, medical records, and physicians caring for patients with positive blood cultures. Of 5,732 blood cultures, 261 (4.6%) were positive, and approximately half of these (51.3%) were categorized as false positive. Positive cultures were significantly more likely to be true positives if obtained from patients with malignancies or if they became positive within the first 48 hours of incubation.

Analysis of catecholamine and vasoactive peptide release in intracranial arterial venous malformations.

Craniotomy for resection of cerebral arterial venous malformation has been associated with postoperative hypertension, which necessitates administration of large doses of antihypertensive medications to control blood pressure. Controlling blood pressure is essential because hypertensive episodes can lead to postoperative cerebral hemorrhage with increases in morbidity and mortality. We measured vasoactive peptide and catecholamine release in 13 patients who underwent resection of an arterial venous malformation and in a control group of 6 patients who presented for clipping of unruptured cerebral aneurysms. Plasma renin activity, angiotensin I and II, vasopressin, aldosterone, epinephrine, and norepinephrine levels were measured intraoperatively and for 36 h postoperatively. Analysis of variance was used to assess sample and group effects. A significant interaction between sample and groups was found for norepinephrine (p < 0.001) and renin (p = 0.002). Our data suggest that elevated plasma renin and norepinephrine levels are in part responsible for postoperative hypertension in patients undergoing resection of arterial venous malformations. Blocking the release of these hormones may help control blood pressure after surgery for removal of arterial venous malformations.

The epidemiology of chest and leg wound infections following cardiothoracic surgery.

The occurrence of wound infections following cardiothoracic surgery has significant implications. However, the epidemiology of all chest and leg wound infections is infrequently described, and the effects on morbidity, mortality, and cost of care remain undefined. We identified 182 superficial and deep chest and leg infections in 163 patients following 1,554 coronary artery bypass graft (CABG), valve, and CABG/valve procedures over 30 months. The overall infection rate was 11.7%; infections of specific sites involved in the 1,554 procedures occurred at the following rates: 3.1%, superficial chest wounds; 2.3%, deep chest wounds; 4.6%, superficial leg wounds; and 2.2%, deep leg wounds. Chest infection rates were similar for all procedures. Multiple infections occurred in 9.8% of patients and were associated with female sex, diabetes, and prolonged surgery (P < .05). Purulent drainage and fever were more common in chest infections; erythema and pain were more common in leg infections (P < .05). Staphylococcus aureus (32.9%), coagulase-negative staphylococci (27.4%), and Enterobacteriaceae (26.0%) were identified most commonly. Enterobacteriaceae were more commonly isolated from leg wounds (P < .05). Adverse outcomes included reexploration (20.9%), flap surgery (12.3%), and death (4.3%). All adverse outcomes were more commonly associated with deep chest infections (P < .05), but superficial chest and leg infections also had a substantial impact on cardiothoracic surgery-related morbidity. Studies are needed to define site-specific risk factors so that the full potential of prevention and control measures can be realized.

Retrolabyrinthine transtentorial approach to lesions of the anterior cerebellopontine angle.

Various surgical approaches to the cerebellopontine angle have been used for removal of acoustic neuromas. A retrolabyrinthine transtentorial approach has been developed that allows (1) access to the anterior cerebellopontine angle and all portions of the basilar artery, (2) extra dural retraction of the lateral sinus and cerebellum while avoiding the vein of Labbé, and (3) preservation of hearing. This approach allows good exposure of tumor and accurate visualization of cranial nerves. To avoid complications, control of spinal fluid is mandatory and great care must be taken to avoid injury of the cranial nerves. The retrolabyrinthine or translabyrinthine transtentorial approach enables skilled neurosurgeons and neurotologists to gain access to lesions that are located in areas difficult to approach.

The effect of a mannose binding protein on macrophage interactions with Candida albicans.

A soluble mannose binding protein (MBP), obtained from rabbit serum, was found to inhibit phagocytosis of Candida albicans by bone marrow derived, cultured murine macrophages. During in vitro incubation of yeast with lymphocyte-free macrophage populations uptake of the yeast was significantly reduced at MBP concentrations of 5 micrograms/ml. A similar reduction in yeast phagocytosis was produced by dextrose, d-fucose, l-fucose, d-mannose and alpha-methyl-d-mannoside but required saccharide concentrations of 25-50 mg/ml. Inhibition of phagocytosis of the yeast also resulted from pretreatment of either the macrophages or the yeasts with MBP followed by washing. As expected, the addition of mannan to the assay medium blocked the inhibitory effect of MBP for uptake of C. albicans. These findings suggest that both cell bound and soluble mannose receptors may be important modulators of macrophage-Candida interactions.

T-cell chronic lymphocytic leukemia. Unusual morphologic, phenotypic, and karyotypic features in association with light chain amyloidosis.

BACKGROUND: Lymphocytes that display a phenotype of mature B-cells, T-cells, natural killer (NK) cells, or a combination of T-cells and NK cells can be found in patients with lymphoproliferations that manifest as expansions of peripheral blood lymphocytes (PBL). If these PBL expansions exhibit clonality, they can be classified as chronic lymphocytic leukemia (CLL). METHODS/RESULTS: A patient who had two simultaneous, clonal lymphoproliferative disorders manifested as an unusual T-cell CLL in conjunction with systemic light chain amyloidosis is described. Gene rearrangement studies of the PBL of the patient showed clonal rearrangements of both the T-cell receptor beta (T beta) chain and the immunoglobulin genes. Additional immunologic and microscopic studies of the T-cells of the patient showed that they were large, agranular, CD4+ T-cells that also expressed the NK cell marker CD57. Cytogenetics disclosed an unusual karyotype in the PBL. CONCLUSIONS: The pathogenesis of this T-cell CLL and whether it truly represents a malignant disorder, as well as its relation to amyloidosis, is discussed.

Complementary use of computed tomography and magnetic resonance imaging in assessing skull base lesions.

Twenty-six patients underwent computed tomography (CT) and magnetic resonance imaging (MRI) of skull base lesions at the Cleveland Clinic Foundation. CT provided improved bone detail, documenting invasion of the lamina papyracea, orbital floor, fovea ethmoidalis, cribriform plate, pterygoid plates, hard palate, and skull base. MRI defined invasion of the orbit, dura, brain, and cavernous sinus. Improved soft-tissue-tumor interface was evident on MRI. MRI was superior to CT in determining carotid artery involvement. MRI distinguished between tumor and retained secretions in the paranasal sinuses. Combining radiographic tumor staging reliably predicted surgical findings; however, MRI consistently yielded sufficient diagnostic information and the additional expense of performing two imaging procedures may not be justified.

Natural history of the cavernous angioma.

The incidence and natural history of the cavernous angioma have remained unclear in part because of the difficulty of diagnosing and following this lesion prior to surgical excision. The introduction of magnetic resonance (MR) imaging has improved the sensitivity and specificity of diagnosing and following this vascular malformation. Seventy-six lesions with an MR appearance typical of a presumed cavernous angioma were discovered in 66 patients among 14,035 consecutive MR images performed at the Cleveland Clinic between 1984 and 1989. Follow-up studies in 86% of the cases over a mean period of 26 months provided 143 lesion-years of clinical survey of this condition. The most frequent presenting features were seizure, focal neurological deficit, and headache. While most lesions exhibited evidence of occult bleeding on MR imaging, there was overt hemorrhage in seven of the 57 symptomatic patients and only one overt hemorrhage occurred during the follow-up interval. The annualized bleeding rate was 0.7%. Analysis of the hemorrhage group revealed a significantly greater risk of overt hemorrhage in females. Pathological confirmation of cavernous angioma was obtained in all 14 surgical cases. This information assists in rational therapeutic planning and prognosis in patients with MR images showing lesions suggestive of cavernous angioma.

Symptomatic Chiari malformation in adults: a new classification based on magnetic resonance imaging with clinical and prognostic significance.

Thirty-five consecutive adults with Chiari malformation and progressive symptoms underwent surgical treatment at a single institution over a 3-year period. All patients underwent magnetic resonance imaging scan before and after surgery. Images of the craniovertebral junction confirmed tonsillar herniation in all cases and allowed the definition of two anatomically distinct categories of the Chiari malformation in this age group. Twenty of the 35 patients had concomitant syringomyelia and were classified as Type A. The remaining 15 patients had evidence of frank herniation of the brain stem below the foramen magnum without evidence of syringomyelia and were labeled Type B. Type A patients had a predominant central cord symptomatology; Type B patients exhibited signs and symptoms of brain stem or cerebellar compression. The principal surgical procedure consisted of decompression of the foramen magnum, opening of the fourth ventricular outlet, and plugging of the obex. Significant improvement in preoperative symptoms and signs was observed in 9 of the 20 patients (45%) with syringomyelia (Type A), as compared to 13 of the 15 patients (87%) without syringomyelia (Type B). Postoperative reduction in syrinx volume was observed in 11 of the 20 patients with syringomyelia, including all 9 patients with excellent results. Magnetic resonance imaging has allowed a classification of the adult Chiari malformation in adults based on objective anatomic criteria, with clinical and prognostic relevance. The presence of syringomyelia implies a less favorable response to surgical intervention.

Surgical management of syringomyelia: a five year experience in the era of magnetic resonance imaging.

We summarize our experience with 59 consecutive surgically managed cases of syringomyelia (SM) over a 5 year period. All cases had magnetic resonance imaging (MRI) preoperatively and postoperatively. Twenty-eight patients presented with SM and the adult Chiari (Chiari I) malformation (SM-ACM), 6 patients had post traumatic syrinxes, 14 patients had syrinxes associated with an intramedullary neoplasm, 3 patients had syringomyelia associated with spinal arachnoiditis and 8 patients had idiopathic syringomyelia. Holocord syrinxes were more often associated with SM-ACM, while focal syrinxes were associated with posttraumatic, spinal arachnoiditis and neoplastic conditions. In all cases with neoplasms the MRI revealed parenchymal intramedullary signal abnormalities in addition to the syrinx cavity. Posterior fossa decompression with obex plugging (the Gardner operation) was the procedure of choice for SM-ACM and for idiopathic holocord syringomyelia. Exploration and drainage of the syrinx with or without shunting was carried out mainly for focal syrinxes associated with trauma and neoplasm. Patients with SM-ACM responded well to posterior fossa decompression with satisfactory results in 24/28 patients. Idiopathic SM is probably a forme fruste of SM-ACM and when treated with the Gardner procedure showed good results in all 8 patients. Posttraumatic and neoplastic SM had the least predictable results with surgery. The disappearance of the syrinx on postoperative MRI correlated well with a good surgical outcome.

Anticryptococcal activity of amphotericin B-stimulated macrophages.

Amphotericin B (AmB) and its methyl ester derivative (AME) are immunoadjuvants with macrophage stimulating properties. Cultures containing AmB and murine peritoneal macrophages showed synergistic anticryptococcal activity. The antifungal activity was associated with AmB-stimulated macrophages and with their culture supernatants. Photoinactivation of the residual AmB in the macrophage culture supernatant did not result in the loss of antifungal activity. AmB-stimulated macrophage culture supernatants inhibited the growth of C. neoformans in a dose responsive manner and the activity was destroyed by incubation at 100 degrees C but not at 60 degrees C.

Amphotericin B selectively stimulates macrophages from high responder mouse strains.

Lymphoid cells from most inbred mouse strains respond to amphotericin B (AmB)-induced immunostimulation. However, C57BL/6 mice and related strains display low or absent lymphoid cell stimulation by AmB and enhanced susceptibility to AmB toxicity. Experiments reported here show that in vitro incubation with AmB can stimulate AKR (AmB-high responder strain) macrophage proliferation. Intraperitoneal injection of AKR mice with AmB also elicits a population of macrophages primed for enhanced oxidative burst activity after triggering by zymosan particles. Under the same experimental conditions, AmB elicits a population of very weakly responsive macrophages from C57BL/6 mice. The low responsiveness of C57BL/6 macrophages correlates with previous observations that AmB is a potent immunoadjuvant and B cell mitogen in most inbred strains, but it selectively lacks immunoadjuvant effects in C57BL/6 mice and it also fails to induce polyclonal B cell stimulation in their spleen cell suspensions. Similarly, in measurements of protein synthesis in vitro, high concentrations of AmB produce a greater inhibition of protein synthesis in C57BL/6 peritoneal macrophages than in parallel cultures of AKR macrophages. These findings support the hypothesis that the macrophage is an important target cell in the mediation of AmB-induced immunomodulation.

Vascular pressures and cortical blood flow in cavernous angioma of the brain.

This study was designed to investigate the hemodynamic characteristics of cavernous angiomas of the brain. Five adult patients with a cavernous angioma underwent local cortical blood flow studies and vascular pressure measurements during surgery for the excision of the cavernous angioma. Clinical presentation included headache in four patients, seizures in four patients, and recurring diplopia in one patient. Magnetic resonance imaging demonstrated the cavernous angiomas in all patients and revealed an associated small hematoma in two. Four patients with a cerebral cavernous angioma were operated on in the supine position and the remaining patient, whose lesion involved the brain stem, was operated on in the sitting position. Mean local cortical blood flow (+/- standard error of the mean) in the cerebral cortex adjacent to the lesion was 60.5 +/- 8.3 ml/100 gm/min at a mean PaCO2 of 35.0 +/- 0.6 torr. Mean CO2 reactivity was 1.1 +/- 0.2 ml/100 gm/min/torr. The local cortical blood flow results were similar to established normal control findings. Mean pressure within the lesion in the patients undergoing surgery while supine was 38.2 +/- 0.5 mm Hg; a slight decline in cavernous angioma pressure occurred with a drop in mean systemic arterial blood pressure and PaCO2. Mean pressure in the cavernous angioma in the patient operated on in the sitting position was 7 mm Hg. Jugular compression resulted in a 9-mm Hg rise in cavernous angioma pressure in one supine patient but no change in the patient in the sitting position. Direct microscopic observation revealed slow circulation within the lesions. The hemodynamic features demonstrated in this study indicate that cavernous angiomas are relatively passive vascular anomalies that are unlikely to produce ischemia in adjacent brain. Frank hemorrhage would be expected to be self-limiting because of relatively low driving pressures.

Intracranial dural arteriovenous malformations: factors predisposing to an aggressive neurological course.

The natural history of cranial dural arteriovenous malformations (AVM's) is highly variable. The authors present their clinical experience with 17 dural AVM's in adults, including 10 cases with an aggressive neurological course (strictly defined as hemorrhage or progressive focal neurological deficit other than ophthalmoplegia). Two of these 10 patients died prior to surgical intervention and a third was severely disabled by intracerebral hemorrhage. Six patients underwent surgical resection of their dural AVM, with preparatory embolization in two cases. One patient received embolization and radiation therapy without surgery. Six of the seven cases without an aggressive neurological course were treated conservatively, and the seventh patient underwent embolization of a cavernous sinus dural AVM because of worsening ophthalmoplegia. In order to clarify features associated with aggressive behavior, a comprehensive meta-analysis was performed on 360 additional dural AVM's reported in the literature with sufficiently detailed clinical and angiographic information. The location and angiographic features of 100 aggressive cases were compared to those of 277 benign cases. No location of dural AVM's was immune from aggressive neurological behavior; however, an aggressive neurological course was least often associated with cases involving the transverse-sigmoid sinuses and cavernous sinus and most often associated with cases at the tentorial incisura. Contralateral contribution to arterial supply and rate of shunting (high vs. low flow) did not correlate with aggressive neurological behavior as defined. Leptomeningeal venous drainage, variceal or aneurysmal venous dilations, and galenic drainage correlated significantly (p less than 0.05) with aggressive neurological presentation. The latter three angiographic features often coexisted in the same dural AVM. It is concluded that these features significantly increase the natural risk of dural AVM's, and warrant a more vigilant therapeutic strategy.

Intracranial hypertension associated with unruptured cerebral arteriovenous malformations.

Only 6 patients with intracranial hypertension associated with unruptured cerebral arteriovenous malformations have been reported. We report 6 additional patients seen at the Cleveland Clinic during the past 10 years. The average age was 28 years (range, 19-44 years); 4 were women. Symptoms and signs included papilledema (6 patients), headache (6), transient nonepileptic focal symptoms (4), visual obscurations (3), ipsilateral carotid or ocular bruits (3), abnormal visual fields (3), focal seizures (2), and progressive visual loss (1). Enhanced computed tomography (CT) or magnetic resonance imaging (MRI) demonstrated the malformations in all 6 patients. The malformations were large, supplied by the branches of the middle and anterior cerebral arteries, with the posterior cerebral artery contributing in 3 patients, and all drained into the superior sagittal sinus. Associated venous obstruction was seen in 2 patients. Four patients underwent excision of the arteriovenous malformation, with resolution of papilledema in all 4. Measurements of cortical arterial and venous pressures during surgery in 3 patients showed decreased feeding artery pressures and elevated draining vein pressures, which normalized after removal of the malformation. Treatment in the 2 remaining patients consisted of medical therapy (acetazolamide, furosemide, steroids) alone in 1 patient, and in conjunction with proton beam radiation in the other. Papilledema resolved in the former patient, but the patient receiving proton beam radiation still had papilledema 2 years later. Intracranial hypertension associated with unruptured cerebral arteriovenous malformations occurs in young patients with high flow malformations that drain into the superior sagittal sinus, and is likely the result of increased cortical venous and superior sagittal sinus pressure. Excision of the malformation effectively reduces the intracranial pressure.

Internal carotid artery occlusion for cavernous segment aneurysm.

We review our recent experience with occlusion of the cervical internal carotid artery (ICA) in 15 patients with symptomatic aneurysms of the cavernous segment. All the patients were women and ranged in age from 38 to 74 years. Ten patients sought treatment initially for ophthalmoplegia, 9 for retro-orbital pain, 8 for facial paresthesia, and 3 for loss of vision. Two patients had symptoms of transient ocular or brain ischemia. The diameter of the aneurysm was greater than 3 cm in 10 patients. Ten patients underwent gradual occlusion of the ICA by Selverstone clamp under anticoagulation and monitoring of neurological status. One patient underwent ligation of a severely stenotic ICA under general anesthesia and electroencephalographic monitoring. Four patients underwent trapping of the aneurysm (after attempts at direct obliteration) under electroencephalographic and cerebral blood flow monitoring. Two patients with incompetent circle of Willis collaterals underwent prophylactic superficial temporal artery to middle cerebral artery bypass surgery prior to ICA occlusion. There was no postoperative clinical change in 9 patients. Ophthalmoplegia improved in 2 patients, and facial pain improved in 3. Three patients developed new extraocular muscle palsies within hours of ICA occlusion; these resolved in all patients by 1 week postoperatively. No change in aneurysm size was documented by serial postoperative computed tomographic or magnetic resonance imaging scans. After a follow-up of 5 to 6 years (range, 6 months-9 years), 11 patients have remained neurologically stable. Two patients experienced delayed transient worsening of visual or facial symptoms.(ABSTRACT TRUNCATED AT 250 WORDS)

The effect of subarachnoid hemorrhage on blood and CSF atrial natriuretic factor.

Atrial natriuretic factor (ANF) is a diuretic natriuretic peptide hormone produced by both the heart and brain which has been postulated to play a role in the hemodynamic and sodium instability that frequently follows subarachnoid hemorrhage (SAH). Levels of ANF were measured in 12 patients with nontraumatic SAH and nine control patients with unruptured cerebral aneurysms. At surgery, the mean plasma ANF level (+/- standard deviation) of the SAH group was significantly higher than that of the control group (158.1 +/- 83.8 vs. 57.8 +/- 45.3 pg/ml, respectively; p = 0.01). There was no significant difference in serum sodium concentration, blood pressure, or central venous pressure between these groups. Nine patients with SAH due to aneurysm rupture had plasma ANF levels similar to those in three patients with SAH due to other causes. Four patients with moderate to severe SAH had significantly higher mean cerebrospinal fluid (CSF) ANF values (17.7 +/- 12.8 pg/ml) than five patients with minimal SAH (0.6 +/- 0.9 pg/ml) or the control group of nine patients (3.7 +/- 1.3 pg/ml) (p less than 0.05). Five patients with moderate to severe SAH had significantly higher plasma ANF values (202.6 +/- 72.2 pg/ml) than five with minimal SAH (86.8 +/- 29.2 pg/ml) or the control group (57.8 +/- 45.3 pg/ml) (p less than 0.05). Plasma ANF values were substantially higher than CSF ANF content in the SAH group (p less than 0.01) and in the control group (p = 0.05). From these data it is concluded that: 1) plasma ANF is elevated significantly after SAH; 2) this rise appears unrelated to the cause of hemorrhage, serum sodium concentration, blood pressure, or central venous pressure, but is related to the extent of the hemorrhage; 3) ANF concentrations in the CSF are significantly lower than in plasma, and are elevated after moderate to severe SAH; and 4) the source of CSF ANF is probably the plasma, and the source of plasma ANF is likely the heart.