Acute respiratory distress syndrome due to methicillin-resistant Staphylococcus aureus sepsis in hyper-IgE syndrome

We report the case of a 34 year old woman with acute respiratory distress syndrome (ARDS) and disseminated intravascular coagulation (DIC) due to methicillin-resistant Staphylococcus aureus (MRSA) sepsis with hyperimmunoglobulin E syndrome (HIES). Although chemotactic activity of neutrophils was impaired in this patient, neutrophils accumulated in the lungs as assessed by bronchoalveolar lavage fluid (BALF) counts. In addition to antibiotics and oxygen therapy, the administration of recombinant human granulocyte colony-stimulating factor (rhG-CSF) resulted in a remarkable recovery.     

Sporotrichoid lymphangitis due to Staphylococcus aureus in a diabetic patient

We describe a case of sporotrichoid lymphangitis (nodular lymphangitis or lymphocutaneous syndrome) that was an unusual clinical presentation of Staphylococcus aureus infection in a diabetic patient. Common pyogenic bacteria should be considered in the differential diagnosis of sporotrichoid lymphangitis.     

Environmental contamination due to methicillin-resistant Staphylococcus aureus: possible infection control implications

OBJECTIVE: To study the possible role of contaminated environmental surfaces as a reservoir of methicillin-resistant Staphylococcus aureus (MRSA) in hospitals. DESIGN: A prospective culture survey of inanimate objects in the rooms of patients with MRSA. SETTING: A 200-bed university-affiliated teaching hospital. PATIENTS: Thirty-eight consecutive patients colonized or infected with MRSA. Patients represented endemic MRSA cases. RESULTS: Ninety-six (27%) of 350 surfaces sampled in the rooms of affected patients were contaminated with MRSA. When patients had MRSA in a wound or urine, 36% of surfaces were contaminated. In contrast, when MRSA was isolated from other body sites, only 6% of surfaces were contaminated (odds ratio, 8.8; 95% confidence interval, 3.7-25.5; P < .0001). Environmental contamination occurred in the rooms of 73% of infected patients and 69% of colonized patients. Frequently contaminated objects included the floor, bed linens, the patient's gown, overbed tables, and blood pressure cuffs. Sixty-five percent of nurses who had performed morning patient-care activities on patients with MRSA in a wound or urine contaminated their nursing uniforms or gowns with MRSA. Forty-two percent of personnel who had no direct contact with such patients, but had touched contaminated surfaces, contaminated their gloves with MRSA. CONCLUSIONS: We concluded that inanimate surfaces near affected patients commonly become contaminated with MRSA and that the frequency of contamination is affected by the body site at which patients are colonized or infected. That personnel may contaminate their gloves (or possibly their hands) by touching such surfaces suggests that contaminated environmental surfaces may serve as a reservoir of MRSA in hospitals.     

The genome of Staphylococcus aureus: a review

The genome of Staphylococcus aureus consists of a single circular chromosome (2.7-2.8 mbp) plus an assortment of extrachromosomal accessory genetic elements: conjugative and nonconjugative plasmids, mobile elements (IS, Tn, Hi), prophages and other variable elements. Plasmids (1-60 kbp) are classified into 4 classes and there are 15 known incompatibility groups. Mobile elements of the genome (0.8-18 kbp) appear in the chromosome or in plasmids of classes II and III. Prophages (45-60 kbp) are integrated in the bacterial chromosome, and they are UV- or mitomycin-inducible. Temperate bacteriophages of S. aureus are members of the Siphoviridae and the serological groups A, B and F occur most frequently. In the paper presented, the characteristics of chromosome, plasmids, transposons and other genetic elements of S. aureus genome are given and an alphabetical list of known genes of this species is included.     

Cytokine expression in a rat model of Staphylococcus aureus endophthalmitis

PURPOSE: To examine the ability of viable Staphylococcus aureus to induce the production of tumor necrosis factor (TNF)-alpha, interleukin (IL)-1beta, cytokine-induced neutrophil chemoattractant (CINC), and interferon (IFN)-gamma after intravitreal injection. METHODS: Experimental rat eyes were injected with a 25-microl volume of approximately 80 colony-forming units of viable S. aureus; control eyes received sterile saline. Eyes were graded daily for signs of clinical inflammation and were removed 6, 24, 48, and 72 hours after injection. One group was prepared for histologic analysis, and vitreous was removed from the other group for cytokine analysis, using standard enzyme-linked immunosorbent assay procedures. RESULTS: TNF-alpha, IL-1beta, CINC, and IFN-gamma were detected in experimental vitreous samples at increased levels that peaked at 24 hours. TNF-alpha, IL-1beta, and CINC declined at 48 hours, but IFN-gamma remained elevated. At 72 hours, levels returned to baseline. Statistically significant elevations of TNF-alpha, IL-1beta, and CINC were detected in experimental samples at 24, but not at 6 and 48 hours compared with levels in saline control samples (P < 0.03). A statistically significant increase in IFN-gamma was detected at 24 and 48 hours compared with control levels (P < 0.03). In experimental animals, clinical inflammation and inflammatory cells peaked at 24 hours, persisted at 48 hours, and began to decline thereafter. Neutrophils were the predominant inflammatory cell detected at 24 (72.3% of cells) and 48 (60.1%) hours. By 72 hours, the total number of inflammatory cells had decreased by 75.0%, and the cellular infiltrate had changed so that neutrophils equaled monocytes-macrophages. CONCLUSIONS: S. aureus induced the expression of TNF-alpha, IL-1beta, CINC, and IFN-gamma. The time course of these cytokine levels could account for the clinical inflammatory responses and the entry and decline of vitreous cells in this model of bacterial endophthalmitis.     

Methicillin-resistant Staphylococcus aureus: a four-year experience in a spinal cord injury unit in Spain

Methicillin-Resistant Staphylococcus aureus (MRSA) infection poses a problem for both acute and long-term-care facilities, Spinal Cord Injury units included. This paper describes the 4-year evolution of MRSA outbreaks in a SCI unit in a university hospital where control measures were implemented from the first case detected. The protocol procedure was as follows: contact isolation, washing with antiseptic soap both those infected and those sharing the same room, contacts study and monitoring of MRSA patients up to the time when three consecutive negative cultures (sampled at time lapses of over 48 h) were obtained, antiseptic soap for the health-care personnel to wash their hands, and cultures of the nares done on the personnel in the event of an outbreak. Twenty-one (3.4%) MRSA positive cases were detected out of 550 admissions registered during the study period (November 1990 through October 1994). The evolution occurred in three outbreaks and six isolated MRSA positive patients without secondary cases. 71.5% of the cases were nosocomial. Seven (33%) were colonizated and 14 (67%) infected. The 14 patients infected presented 15 infections: nine with urinary tract infections, three surgical wound infections, two tracheostomy wound infections, and one patient with a decubitus ulcer infection. Two of those with urinary tract infections presented with secondary sepsis. No carriers were detected amongst the personnel. Urinary tract colonizations responded to treatment with cotrimoxazol except in two cases in which combined treatment was required (cotrimoxazol plus rifampicin). The patients with a MRSA positive tracheal aspirate were negative after combined treatment. Wounds and cultures of the nares responded favorably to initial treatment. One of the patients with a urinary tract infection and sepsis died the infection being a contributing cause. The prospective follow-up of the patients with MRSA positive cultures and the precocious implementation of isolation measures allow for the limitation of transmission, even although complete eradication is not possible.     

The lipase from Staphylococcus aureus. Expression in Escherichia coli, large-scale purification and comparison of substrate specificity to Staphylococcus hyicus lipase

The genes coding for the mature part of the lipases from Staphylococcus aureus NCTC8530 and Staphylococcus hyicus have been cloned and overexpressed in Escherichia coli as fusion proteins with an N-terminal hexa-histidine tag. The enzymes accumulated in the cytoplasm and were purified using sequential precipitation with protamine sulphate and ammonium sulphate, followed by metal-affinity and hydroxyapatite chromatography. The yield of pure lipase was 4.5 mg/g wet cells for S. aureus lipase and 13 mg/g for S. hyicus lipase. The purified enzymes need calcium for activity, albeit with different affinities, and a low residual activity was found in the absence of calcium. In contrast to S. hyicus lipase, not only strontium but also barium can replace calcium with full retention of activity of S. aureus lipase. Whereas S. hyicus lipase is optimally active at pH 8.5, the optimum pH for enzymatic activity for S. aureus lipase was found to be pH 6.5. The S. aureus lipase has a narrow substrate specificity: short-chain triacylglycerols and acyl esters of both p-nitrophenol and umbelliferone are readily degraded, whereas medium- and long-chain lipids, as well as phospholipids, are poor substrates. In contrast, S. hyicus lipase prefers phospholipids as substrate and hydrolyses neutral lipids irrespective of their chain length. The results are discussed in view of the large sequence similarity between both lipases.     

The protective effect of L-arginine on ischemia-reperfusion injury in rat skin flaps

The objective of this study was to examine whether the administration of L-arginine, a precursor of nitric oxide and substrate of nitric oxide synthase, prior to reperfusion could lead to decrease in neutrophil-mediated tissue injury and improved flap survival. Epigastric island skin flaps were elevated in 70 rats and rendered ischemic. Thirty minutes prior to reperfusion, the rats were treated with intraperitoneal saline (n = 15), L-arginine (n = 15), D-arginine (n = 15), or N omega-nitro-L-arginine methylester plus L-arginine in equimolar amounts (n = 15). Flap survival at 7 days and neutrophil counts at 24 hours were evaluated. Flap necrosis as expected in the sham group of animals (n = 10) was 0.0 percent, while the control (saline-treated) animals had 59.6 percent necrosis. Animals treated with L-arginine demonstrated a significant decrease in flap necrosis to 12.7 percent. This protective effect was almost completely negated by N omega-nitrol-L-arginine methylester, which significantly increased flap necrosis to 49.3 percent and was much less pronounced with D-arginine (28.6 percent). Neutrophil counts were significantly decreased in flaps from L-arginine-treated and sham animals versus both saline and N omega-nitro-L-arginine methylester-treated groups. We conclude that administration of L-arginine prior to reperfusion can significantly reduce the extent of flap necrosis and flap neutrophil counts due to ischemia-reperfusion injury. This protective effect is completely negated by nitric oxide synthase inhibition. Since L-arginine reduces the number of neutrophils within the flap and the extent of flap necrosis only in the presence of active nitric oxide synthase, we hypothesize that this protective effect of L-arginine on ischemia-reperfusion injury is secondary to a nitric oxide-mediated suppression of neutrophil-mediated injury.     

Staphylococcus aureus meningitis in a patient with acquired immunodeficiency syndrome

Meningitis due to Staphylococcus aureus is well described but uncommon. Most cases arise as a complication of neurosurgical interventions or head trauma, although some arise spontaneously. To our knowledge, no case of S. aureus meningitis has been previously reported in a person with the acquired immunodeficiency syndrome (AIDS). Herein we describe a case of S. aureus meningitis in a person with AIDS who had no history of a neurosurgical procedure, head trauma, or overwhelming bacteremia. Treatment of this infection was successful. S. aureus should be added to the list of potential pathogens that can cause spontaneous meningitis in people with AIDS.     

Vitamin C reduces ischemia-reperfusion injury in a rat epigastric island skin flap model

We have examined the effects of lumbar extradural administration of 1% etidocaine 10 ml on somatosensory evoked potentials to posterior tibial nerve stimulation measured in the cervical extradural space. Eight patients, anaesthetized with propofol and nitrous oxide, were studied before hysterectomy and a control group received a similar anaesthetic and 0.9% sodium chloride solution 10 ml in the lumbar extradural space. Etidocaine decreased significantly overall amplitude of the evoked potentials and the amplitudes of all peaks, between 30 and 50 min after extradural injection. The effects of etidocaine on spinal cord conduction were greater than those found previously for lignocaine and bupivacaine, suggesting that it is the local analgesic of choice for inhibiting afferent conduction.     

Protective effect of salvianolic acid a on ischemia-reperfusion induced injury in isolated rat heart

BACKGROUND: Recognition of advanced abdominal pregnancy and care of the patient afflicted with it may present formidable challenges. Aside from the difficulty of diagnosing the problem and thereby delaying necessary intervention, management can be difficult at best, even when the condition is relatively uncomplicated. When it is compounded by a life-threatening complication, such as uncontrollable hemorrhage, it challenges the skills of the most experienced obstetrician and the resources of the best-equipped facility and its personnel. CASE: Partial placental separation was encountered at surgery; it progressed intraoperatively despite the care taken to avoid disturbing the placental implantation site. Severe hemorrhage was controlled by a combination of aortic compression, packing and use of large "liver" sutures incorporating the uterine wall for tamponade of the principal placental implantation site, on the mesentery. CONCLUSION: It is important to be prepared to deal with the complication of intense intraabdominal bleeding in the course of intraoperative management of abdominal pregnancy.     

The effects of thyroid hormone modulation on rat liver injury associated with ischemia-reperfusion and cold storage

We investigated the effects of thyroid hormone modulation on liver injury associated with ischemia-reperfusion (I-R) and cold storage in rats. First, euthyroid and thyroxine (T4)-pretreated rats were exposed in vivo to 20-min global liver ischemia, then 30-min reperfusion. Liver injury was assessed by measuring serum alanine aminotransferase (ALT) levels. Liver concentrations of adenine nucleotides, reduced glutathione (GSH), and oxidized glutathione were evaluated. Second, rats were given the antithyroid drug propylthiouracil (PTU). Livers stored at 0-1 degrees C in Euro-Collins' solution for 20 h were reperfused at 37 degrees C for 15 min. Lactate dehydrogenase (LDH) in the effluent perfusate and bile flow were evaluated during reperfusion. Serum ALT levels increased after ischemia and I-R. ALT increased significantly more in T4-pretreated than in euthyroid rats after ischemia and I-R. Preischemic levels of adenosine triphosphate (ATP) were significantly lower in livers from T4-pretreated than in euthyroid rats (6.22 +/- 0.7 and 11 +/- 0.9 nmol/mg protein, respectively; P < 0.05). After ischemia, liver ATP was similarly reduced in T4-pretreated and euthyroid rats. After reperfusion, ATP partially recovered in euthyroid rats but remained low in T4-pretreated rats (6.7 +/- 1.0 and 1.91 +/- 0.7 nmol/mg protein, respectively; P < 0.05). Preischemic levels of liver GSH decreased to 44% in T4-pretreated rats. After ischemia, GSH decreased similarly in euthyroid and T4-pretreated rats. GSH recovered promptly after reperfusion in euthyroid rats but remained low in T4-pretreated rats (13.9 +/- 3.3 and 3.9 +/- 0.9 nmol/mg protein, respectively; P < 0.02). During reperfusion after cold storage, LDH in effluent perfusate was significantly lower and bile flow higher in livers from PTU-pretreated rats than from euthyroid rats. The histopathological changes observed after I-R and cold storage confirmed the biochemical findings. Our results suggest that T4 administration exacerbates pretransplant liver damage by increasing liver susceptibility to I-R, whereas PTU administration reduces the liver injury associated with cold storage. Implications: We studied the effects of thyroid hormone modulation on liver injury associated with ischemia-reperfusion and cold storage in rats. Thyroxine administration increased susceptibility to ischemia-reperfusion injury, whereas the antithyroid agent propylthiouracil reduced the deleterious effects associated with cold storage.     

The role of xanthine dehydrogenase (xanthine oxidase) in ischemia-reperfusion injury in rat kidney

Xanthine dehydrogenase (XDH) and xanthine oxidase (XO) are enzymes involved in the metabolism of purines in various organisms. XO produces superoxide radicals, suggesting that is responsible for tissue ischemia-reperfusion injury. To test this notion further studies were performed on rat kidneys and the time course of changes in purine nucleotides, oxypurines and XDH and XO activity was determined. At 24 hours after reperfusion subsequent to 30-minute ischemia, serum creatinine increased to 0.83 +/- 0.74 mg/dl from 0.28 +/- 0.06 mg/dl (the level prior to ischemia, the control). Renal ATP and ADP contents were reduced after ischemia lasting for 30 minutes and restored 10 minutes after reperfusion following 30 minutes of ischemia. The renal AMP content increased after 30 minutes of ischemia and recovered within 10 minutes after reperfusion. The total adenine nucleotide (TAN) content was reduced gradually during ischemia-reperfusion in the rat kidney. Although the energy charge was reduced following 30 minutes of ischemia, it was restored to the control level 10 minutes following reperfusion. Hypoxanthine (HX) and xanthine (X), which had accumulated at 30 minutes after ischemia, were reduced to the control levels 10 minutes after reperfusion. There were no significant changes in the pre-ischemia values of total XDH and XO activities or XDH/XO ratio during the period nor at various time intervals (up to 24 hours) during reperfusion. It was shown that HX and X accumulate without significant conversion of XDH to XO during ischemia. Therefore the putative role of XO in ischemia-reperfusion injury seems to more complex than initially predicted.     

Donor treatment with the lazeroid U74389G reduces ischemia-reperfusion injury in a rat lung transplant model

BACKGROUND: Antioxidant treatment with lazeroids has proven beneficial for the amelioration of reperfusion injury in experimental lung transplantation. This study compares the effect of donor versus recipient treatment on immediate postoperative graft function. METHODS: A model of acute double-lung transplantation in rats was used to assess graft function. Transplanted controls after 2 (group I) and 16 hours of ischemia (group II) were compared to a recipient (group III; 16-hour ischemia) and a donor treatment group (group IV; 16-hour ischemia) using the lazeroid U74389G (6 mg/kg). Serial assessment of alveolar-arterial oxygen difference, dynamic lung compliance, airway and pulmonary vascular resistance was obtained during a 2-hour reperfusion period. Final analysis included survival, weight gain, and histologic examination. RESULTS: Graft function was significantly better after 2 hours of ischemia than in any of the three 16-hour ischemia groups (II, III, IV). After 16 hours of ischemia, donor treatment provided superior graft function with respect to dynamic lung compliance, airway resistance, and alveolar-arterial oxygen difference when compared with groups II and III. The pulmonary vascular resistance was significantly higher in group III when compared with groups II and IV. Graft weight increase reflecting edema was highest in groups III (104%) and II (98%). CONCLUSIONS: After prolonged ischemia only donor treatment with the lazeroid U74389G was able to significantly reduce ischemia-reperfusion-related graft dysfunction.     

Characteristics of pancreatic injury in children: a comparison with such injury in adults

A retrospective study of eight pediatric patients (under 15 years of age) who had pancreatic injuries was undertaken. Comparisons were made with 59 adult patients who sustained pancreatic injuries over the same 15-year period. All the pediatric injuries and 96.6% of the adult resulted from blunt abdominal trauma. Bicycle accidents (children, 75.0%; adults, 0%; P < .001) and automobile accidents (children, 0%; adults, 61.0%; P < .01) were the most common causes of pancreatic injury in the two groups. There was no significant difference in the incidence of abdominal pain or peritoneal irritation between the groups. However, abdominal pain in the adults was poorly localized. Isolated pancreatic injuries were noted in 62.5% of the pediatric patients and in 15.3% of the adult patients (P < .05). Associated intraabdominal injuries were present in 25.0% of the children and in 69.5% of the adults (P < .05). The duodenum was injured in two (25.0%) pediatric patients and in 10 (16.9%) adult patients. Whereas the duodenal injuries in pediatric patients were intramural hematomas without perforation in both cases, all but one of these injuries in adults were perforations or transections (P < .05). There was a significant difference in the type of pancreatic injury between the two groups (P < .05). Surgery was performed in 12.5% of the pediatric cases and in 78.0% of the adult cases (P < .01). There were no deaths among the pediatric patients, but 8.5% of the adults died in the hospital. The difference with respect to clinical course might be related to the differences in cause of injury.     

Protein-A-mediated targeting of bacteriochlorophyll-IgG to Staphylococcus aureus: a model for enhanced site-specific photocytotoxicity

A model for studying the efficiency of photodynamic action with a photosensitizer placed exclusively on the bacterial cell wall has been used. Bacteriochlorophyllide molecules, conjugated to rabbit immunoglobulin G (IgG), were synthesized. The conjugated pigment bacteriochlorophyll (Bchl)-IgG bound with high specificity to protein-A residues naturally exposed on the cell wall of the bacterium Staphylococcus aureus Cowan I. In bacterial suspensions the phototoxicity of the targeted conjugates (0.5-2.5 pigment per IgG molecule) was dose dependent (LD50 = 1.7 microM) in the presence of light (lambda > 550 nm) and inhibited by native IgG but not by ovalbumin, suggesting selective interaction with protein-A on the bacterial cell wall. No dark toxicity was noticed even with the highest conjugate concentration tested. In contrast, the photocytotoxicity of bacteriochlorophyll-serine (Bchl-Ser, LD50 = 0.07 microM) used as a nontargeted control was not inhibited by IgG. In spite of its lower apparent potency, Bchl-IgG was found to be 30 times more efficacious than Bchl-Ser: At LD50, only 66,000 Bchl-IgG molecules were bound per bacterium compared to 1,900,000 molecules of Bchl-Ser. The higher efficacy of Bchl-IgG is explained by its exclusive position on the bacterial cell wall. Consequently, photogeneration of oxidative species is confined to the cell wall and its vicinity, a seemingly highly susceptible domain for photodynamic action. In considering the design of cell-specific sensitizers for bacterial and cancer therapies, it would be beneficial to identify the more discretely sensitive subcellular domains as targets.     

Lysogenic conversion as a factor influencing tolerance to vancomycin in Staphylococcus aureus

The standard, non-lysogenic, bacteriophage-free S. aureus NCTC 8325-4 strain was lysogenized with 15 different, obtained in our laboratory staphylokinase-converting bacteriophages belonging to serological groups A, B and F. MIC and MBC of vancomycin as well as the ratio of MBC to MIC were evaluated for all 15 lysogenic derivatives. The obtained results were compared with those for maternal strain. In the case of eight strains the ratio MBC/MIC showed the presence of tolerance to vancomycin (MBC/MIC > or = 32). Four of the vancomycin-tolerant derivatives were lysogenized with bacteriophages belonging to the serological group A, two were members of group B and two belonged to group F.     

Molecular genotyping of Staphylococcus aureus strains: comparison of repetitive element sequence-based PCR with various typing methods and isolation of a novel epidemicity marker

OBJECTIVE: To detail the characteristics and management of rarely reported and incompletely described dermoid cysts originating in the temporal fossa. DESIGN: Retrospective case series. PARTICIPANTS: Five patients ranging from 2 to 38 years of age with a mass in the temporal region (posterior to the lateral orbital rim) participated. INTERVENTION: Computed tomography (CT) and excisional biopsy were performed. MAIN OUTCOME MEASURES: Clinical and CT characteristics and surgical outcomes were measured. RESULTS: Computed tomography showed cystic lesions, originating from the region anterior to the confluence of the greater wing of the sphenoid, frontal, and zygomatic bones. Displacement of the anteriormost portion of the temporalis muscle was common. Three cysts were isolated to the temporalis fossa, while two showed more extensive bony erosion and extension into the cranial and orbit cavities. At surgical excision, gross rupture of the cysts was noted in two cases, and two were completely liquefied. Histopathology showed variable inflammation surrounding all of the dermoid cysts. All patients did well after surgery. CONCLUSIONS: Dermoid cysts may infrequently occur "primarily" in the temporal fossa. Bone involvement and anterior temporalis muscle displacement are common. An origin from the area anterior to the confluence of the greater wing of the sphenoid, frontal, and zygomatic bones is seen. A coronal approach facilitates wide exposure and excision. When dural extension is suggested on CT, neurosurgical assistance may be required.