Pseudomonas Pneumonia Research Articles

Pulmonale Zygomykose – eine seltene angioinvasive Pilzinfektion

Zusammenfassung Rhizopus‐Arten sind Pilze, die Zygomykosen verursachen. Die Zygomykose umfasst mukokutane, rhinocerebrale, pulmonale, urogenitale und disseminierte Infektionen. Prädisponierende Faktoren sind eine Immunsuppression infolge von schweren Erkrankungen, Immundefekte oder Störungen des Stoffwechsels wie die diabetische Ketoazidose. Rhizopus‐Infektionen sind charakterisiert durch ein angioinvasives Wachstum der Pilze, eine perineurale Invasion und Nekrosen des infizierten Gewebes. Bemerkenswert ist die histopathologisch nachweisbare Invasion von Blutgefässen. Zygomykosen verlaufen häufig letal. Wir berichten über zwei Patienten mit einer pulmonalen Zygomykose, hervorgerufen durch Rhizopus spp.: Pat. 1, weibl. 73 Jahre: Protrahierter Verlauf nach infizierter Hüft‐TEP (abkurtzung für Totalendoprothese) und Infektion eines femoropoplitealen Bypasses des rechten Beines, schließlich Hüftgelenksexartikulation rechts, Pseudomonas‐Pneumonie, Staphylokokkensepsis, schweres septisches Schockgeschen mit akutem Lungen‐ und Nierenversagen, Zustand nach multimodaler Antibiotikatherapie. In der Folge Nachweis von Rhizopus spp. in der BAL, antimykotische Therapie mit Amphotericin B. Pat. 2, männl., 68 Jahre: Zustand nach Nierentransplantation, aktuell Transplantatversagen. Multiple abgelaufene Infektionen. In der Folge abszedierende Pneumonie rechts mit Entwicklung eines Pleuraempyems, darin Nachweis von Rhizopus spp., deshalb Unterlappenresektion und Transplantatnephrektomie wegen Rejektion. Protrahierter septischer Verlauf. Behandlung mit Caspofungin. Beide Verläufe endeten trotz aller intensivmedizinischer Bemühungen letal. Die seltene pulmonale Zygomykose infolge einer Infektion mit Rhizopus spp. entstand bei unseren Patienten infolge einer Immunsuppression, bei einem aufgrund einer Organtransplantation iatrogen induziert, beim anderen infolge einer protrahiert verlaufenden schweren Sepsis. Im Vergleich zu anderen Pilzinfektionen bleibt die Therapie von Rhizopus‐Infektionen schwierig. Ihre starke Affinität zu Gefäßen, in denen sie sich vermehren und ihre Eigenschaft, im Rahmen der vaskulären Invasion eine Thrombosierung und anschließende Infarktbildung herbeizuführen, erschweren die Therapie.

Acute pancreatitis in mice impairs bacterial clearance from the lungs, whereas concurrent pneumonia prolongs the course of pancreatitis.

Nosocomial pneumonia is a feared complication in the critically ill patient. Serious acute pancreatitis is frequently complicated by infections. The objectives of this study were to determine the influence of acute pancreatitis on host defense against Pseudomonas pneumonia and to determine the influence of Pseudomonas pneumonia on the severity of concurrent pancreatitis. A controlled, in vivo laboratory study. Research laboratory of a health sciences university. Female C57Bl/6 mice. Pancreatitis was induced by 12 hourly intraperitoneal injections of cerulein (pancreatitis) or saline (sham) immediately followed by intranasal administration of Pseudomonas aeruginosa (to induce pneumonia) or saline (controls). Mice were killed 24 hrs later. Hence, four groups were studied: sham/control, pancreatitis/control, sham/pneumonia, and pancreatitis/pneumonia mice. When compared with sham/pneumonia mice, pancreatitis/pneumonia mice demonstrated exaggerated lung inflammation, higher bacterial counts in lungs and pancreas, and enhanced dissemination of the infection. Concurrently, pneumonia prolonged the course of pancreatitis, as reflected by histopathology and higher plasma amylase and relative pancreas weights (all p < .05 for the difference between pancreatitis/pneumonia and pancreatitis/control mice), which was associated with the localization of Pseudomonas in the pancreas. Acute pancreatitis impairs host defense against Pseudomonas pneumonia, whereas pneumonia prolongs the course of pancreatitis.

Surveillance of perioperative infections after adult living donor liver transplantation

Aim This study was conducted to clarify the management of perioperative infectious complications after adult living donor liver transplantation (LDLT). Patients and methods Fourteen adult LDLT patients were enrolled in this study. We examined the occurrence of infectious complications in these cases and the relationships of infectious complications to UNOS status and MELD score. Surveillance culture and immunoserologic analyses were performed. From the results of these analyses, we made a diagram of infection surveillance using a matrix of time and sampling site. Using the diagram, we chose sensitive antibiotics as soon as possible. Results The infection site and its pathogen were able to be detected in four (28.5%) patients, all of whom had MRSA infections, together with lung aspergillosis in one case, pseudomonas pneumonia in another, and both in another. Two patients died of lung aspergillosis. Bacteria detected in the airway tended to spread to other sites during the postoperative period. In all four patients in whom infectious diseases were detected, and in a fifth patient in whom the site of infection was not known, the UNOS status was 1. The MELD score was calculated in eight patients, six of whom had high MELD scores (>20). Conclusion Most cases were manageable by choosing and changing antibiotics and antifungal drugs according to the results of surveillance cultures twice a week. However, aspergillosis had an extremely poor prognosis. Patients with a high MELD score or low UNOS status, or both, showed poor prognosis; and in them, multiple drug resistance bacteria caused severe perioperative infectious complications.

A British Second World War veteran with disseminated strongyloidiasis

A case is described of a 78-year-old British veteran of the Second World War (1939–45) who was stationed in Southeast Asia and who developed a recurrent pneumonia with blood eosinophilia. He was treated with steroids, and eventually died with a severe Pseudomonas pneumonia. Just prior to death, larvae of Strongyloides stercoralis were identified in his sputum, and a specific serum ELISA test was later positive. At autopsy no other organs were involved, but bronchoalveolar carcinoma was found. Longstanding (57 years) chronic strongyloidiasis in a veteran who served in Southeast Asia but who was not a prisoner of war is very unusual. The pattern of dissemination was also not that of a true hyperinfection syndrome, and the case demonstrates the continued need for diagnostic vigilance amongst former soldiers who were based in the Far East.

Effect of nitric oxide on capillary hemodynamics and cell injury in the pancreas during Pseudomonas pneumonia-induced sepsis.

Sepsis-induced nitric oxide (NO) overproduction has been implicated in a redistribution of flow from the pancreas making it vulnerable to ischemic injury in septic shock. To test this hypothesis in a remote injury model of normotensive sepsis, we induced Pseudomonas pneumonia in the rat and used intravital video microscopy (IVVM) of the pancreas to measure functional capillary density, capillary hemodynamics [red blood cell (RBC) velocity, lineal density, and supply rate], and lethal cellular damage (propidium iodine staining) at 6 and 24 h after the induction of pneumonia. With pneumonia, plasma nitrite/nitrate [NO2(-)/NO3(-)(NOx(-))] levels were doubled by 21 h (P < 0.05). To assess the effect of NO overproduction on microvascular perfusion, N6-(1-iminoethyl)-L-lysine (L-NIL) was administered to maintain NOx(-) levels at baseline. Pneumonia did cause a decrease in RBC velocity of 23% by 6 h, but by 24 h RBC velocity and supply rate had increased relative to sham by 22 and 38%, respectively (P < 0.05). L-NIL treatment demonstrated that this increase was due to NO overproduction. With pneumonia, there was no change in functional capillary density and only modest increases in cellular damage. We conclude that, in this normotensive pneumonia model of sepsis, NO overproduction was protective of microvascular perfusion in the pancreas.

Pseudomonas pneumonia in infants: an autopsy study

Pseudomonas pneumonia is an uncommon but serious infection in infants, occurring mainly in infants of low birth weight. In this retrospective clinicopathologic correlation study, we reviewed the clinical records and analyzed postmortem lung pathology in 8 infants with pneumonia due to P. aeruginosa. From the histopathology, 2 different pneumonic patterns emerged: a distinctive paucicellular coagulative confluent bronchopneumonia with perivascular bacillary infiltration (7 cases) and a more usual cellular pneumonia without evidence of perivascular organisms (1 case). Clinically, infants with the first type could be considered immunocompromised and had a precipitous course characterized by signs of sepsis, whereas the infant with the second type (who likely had a more normal immune system) had a relatively protracted course with respiratory failure. We conclude that (1) the pattern of pneumonic inflammation correlates with the immune state of infants, similar to what has been reported in adults; (2) among immunocompromised infants, histopathologic signs of bacteremia are prevalent; and (3) the clinical signs do not correlate with the severity of the pathology at autopsy and may reflect sepsis rather than pneumonia. We speculate that the histopathology in this population reflects the virulence of the organism, as well as the immune status of the host.

Aortic Rupture due to Salmonella Infection—Surgical Reconstructive Options

A 51-year-old man was admitted urgently with a 3 week history of back pain. Clinical examination revealed a tender abdomen and a temperature of 39 8C. There was a leucocytosis of 15 900. An abdominal CT scan was immediately performed and this confirmed the presence of a saccular abdominal aortic aneurysm. Because of the presence of retroperitoneal extravasation and a probable rupture, a laparotomy was performed. During para-aortic dissection a large abscess arising from the back of the aorta was found. There was a 25 mm perforation of the aorta which extended up to the left renal artery (Fig. 1). The aorta was resected obliquely above the abscess, preserving the right renal artery. The left renal artery had to be ligated. After debridement the surgical area was filled with omentum. In order to restore the blood circulation distally, we implanted a 6 mm PTFE axillobifemoral bypass. A microbiological swab taken during the procedure grew salmonella enteritidis. About three weeks later the patient suddenly developed acute abdominal pain. A CT scan showed and extended septic aneurysm which had developed around the aortic stump although the patient was on continuous treatment with metronidazole and a cephalosporin. Subsequent surgical revision revealed an infected 10 cm £ 10 cm pulsatile aneurysm surrounding the site of resection of the aorta (Fig. 1). During the following operation the aorta was resected above the celiac trunk and the visceral circulation was restored through an aorto-coeliac bypass using saphenous vein. The right renal blood supply was reestablished through a saphenous vein interposition between the right renal artery and the aorta (Fig. 2). The aneurysm cavity was opened and drained. A further laparotomy performed two days later in order to assess the blood supply of the gastrointestinal tract was satisfactory. After 65 days of ICU treatment complicated because of a protracted pseudomonas pneumonia and 93 days of hospitalisation the patient was discharge home. Antibiotic therapy was stopped three weeks after discharge. Five months later the patient was admitted as an emergency and operated on for disseminated peritonitis caused by multiple small ischaemia-induced perforations in the ascending colon. An intraoperative swab grew the same serotype of salmonella enteritidis as before, and an endogenous reinfection was diagnosed. A right hemicolectomy was performed and because of the poor intestinal blood supply, an EJVES Extra 5, 92–94 (2003) doi: 10.1016/S1533-3167(03)00030-X, available online at http://www.sciencedirect.com on

Interleukin-18 impairs the pulmonary host response to Pseudomonas aeruginosa.

Interleukin-18 (IL-18) is a potent cytokine with many different proinflammatory activities. To study the role of IL-18 in the pathogenesis of Pseudomonas pneumonia, IL-18-deficient (IL-18(-/-)) and wild-type mice were intranasally inoculated with Pseudomonas aeruginosa. IL-18 deficiency was associated with reduced outgrowth of Pseudomonas in the lungs and diminished dissemination of the infection. In addition, pulmonary inflammation (histopathology) and levels of tumor necrosis factor alpha, IL-6, and macrophage inflammatory protein-2 in lungs and plasma were lower in IL-18(-/-) mice. Consistent with results obtained for IL-18(-/-) mice, treatment of wild-type mice with a neutralizing IL-18 binding protein-immunoglobulin G Fc fusion construct also attenuated outgrowth of Pseudomonas compared with that for mice treated with a control protein. These results demonstrate that the presence of endogenous IL-18 activity facilitates inflammatory responses in the lung during Pseudomonas pneumonia, concurrently impairing bacterial clearance.

Acute pancreatitis renders mice more susceptible to pseudomonas pneumonia, which in turn aggravates the severity of pancreatitis. Evidence for a pathological vicious circle

Acute pancreatitis renders mice more susceptible to pseudomonas pneumonia, which in turn aggravates the severity of pancreatitis. Evidence for a pathological vicious circle

The role of flexible bronchoscopy evaluating transplant recipients with suspected pulmonary infections

Comments: This retrospective study assessed the role of FB in the management of organ transplant recipients. Lung transplant recipients with surveillance bronchoscopies were excluded from the study. Indications for FB included suspected pulmonary infection by either abnormal chest radiograph or respiratory symptoms. One hundred sixty-eight FBs were performed in 129 patients. The mean age of patients who underwent transplantation was 50 ± 8.4 years. There were 84 male and 45 female patients. One hundred twenty-one (72%) were lung transplants recipients, 34 (20%) were renal transplant recipients, 6 (4%) were liver transplant recipients, 4 (2%) were heart transplant recipients, and 3 (2%) were bone marrow transplant recipients. Mean posttransplantation time was 30.3 ± 7.1 months (range, 1–61 months posttransplantation). Patients underwent BAL, and the specimens were analyzed for bacteriology, virology, and fungal and mycobacterial cultures. BLB was obtained in 65% of patients. Diagnosis was obtained using FB in 82 patients (49%). Infection was diagnosed in 21 patients (12%), rejection was diagnosed in 25 lung transplant recipients (15%), nonspecific interstitial pneumonitis and bronchiolitis obliterans organizing pneumonia were diagnosed in 34 patients (20%), and malignancy was diagnosed in 2 patients (1.2%). In 86 cases (51%), FB was nondiagnostic. Microorganisms isolated by FB were bacterial in seven cases (one was mycobacterial tuberculosis), fungal in two cases, viral in five cases, and of mixed infection in seven cases. Depending on the results from FB, antimicrobial therapy was changed in 51% of cases. Antibiotic treatment was discontinued in 59 cases (35%). No death was related to FB. Three patients later died of infection: one as a result of Pseudomonas pneumonia, one as a result of cytomegalovirus pneumonitis, and one as a result of mixed pulmonary infection (Pseudomonas, cytomegalovirus, and Aspergillus). Overall hospital mortality in posttransplantation patients with infection was 9.6%. Nonpulmonary causes, such as cardiovascular diseases or malignancy, were causes of death in another 16 patients (11.7%). The authors concluded that FB is an extremely useful tool to evaluate transplant recipients with suspected pulmonary infection. The procedure is safe and should be performed early in any transplant recipients with respiratory symptoms or chest radiograph abnormalities. Both infectious and noninfectious complications are common in patients after solid organ transplantation or bone marrow transplantation. When respiratory symptoms and chest radiographs along with nonrespiratory symptoms of infection appear in these patients, the first consideration is to obtain respiratory specimens to identify the causative agent so that appropriate therapy can be promptly instituted. However, not all patients with respiratory symptoms have underlying infection. Many of the pulmonary features in this group of patients are secondary to noninfectious complications of organ transplant. This study shows that the results from FB led to change in antimicrobial therapy in 51% of cases, and antibiotic treatment was discontinued in 59 cases (35%). These numbers are significant and impressive, compared with several studies that have addressed this issue.

Pancreatitis-associated protein-I is expressed in rat pancreas in pseudomonas pneumonia induced Sepsis

Pancreatitis-associated protein-I is expressed in rat pancreas in pseudomonas pneumonia induced Sepsis

Surfactant protein A and D differently regulate the immune response to nonmucoid Pseudomonas aeruginosa and its lipopolysaccharide.

We investigated the role of the surfactant proteins (SPs) A and D in the pulmonary immune defense of nonmucoid strains of Pseudomonas aeruginosa, the most etiologic agents of nosocomial Pseudomonas pneumonia. We first examined the interactions of recombinant human SP-D dodecamers and purified natural or recombinant human SP-A with two smooth, and two rough, clinical isolates of nonmucoid P. aeruginosa. SP-D bound to all four isolates, but agglutinated only one rough and one smooth strain. SP-D functioned as an opsonin to enhance the uptake of all four strains by the human monocytic cell line Mono Mac 6 (MM6). SP-D also enhanced tumor necrosis factor-alpha secretion by MM6 cells in response to purified lipopolysaccharide (LPS) isolated from the rough, but not the smooth, strains. Although SP-A bound to all four strains, it did not cause bacterial aggregation or enhance uptake. It showed small but statistically significant inhibitory effects on the cytokine response of MM6 cells to one strain of smooth organisms, but did not significantly alter the response to purified LPS. This study in combination with previously published data strongly suggests that SP-D may play important roles in the local innate pulmonary defense against nonmucoid P. aeruginosa of diverse LPS phenotypes, and preferentially augments the cellular response to rough P. aeruginosa endotoxin.

Heparin nebulization attenuates acute lung injury in sepsis following smoke inhalation in sheep.

Pseudomonas pneumonia is a common complication of smoke inhalation injury. Airway casts formed from clotted mucous occur frequently in this condition. A recent report shows that intravenous heparin improves oxygenation and reduces lung damage in a sheep model of smoke inhalation. We hypothesized that nebulized heparin could be an effective means of reducing cast formation. Female sheep (n = 19) were surgically prepared for a study of acute lung injury (ALI). After a tracheotomy, 48 breaths of cotton smoke (<40 degrees C) were inflated into the airway. Afterwards, live Pseudomonas aeruginosa (5 x 10(11) CFU) was instilled into the lung. All sheep were mechanically ventilated with 100% O2 and were divided into four groups: a heparin-nebulized group (n = 5; animals received aerosolized heparin [10,000 I.U.] 1 h after the bacterial instillation and subsequently every 4 h thereafter), an intravenous heparin group (n = 5,300 U/kg/23 h, infusion was started 1 h after the injury), a saline-nebulization group (n = 5; animals received inhaled nebulized saline), and a sham injury group (n = 4, treated in the same fashion, but no injury). The animals were sacrificed after 24 h of mechanical ventilation, and lung samples were harvested. Sheep exposed to lung injury presented with typical hyperdynamic cardiovascular changes and a corresponding drop in PaO2. These changes were significantly attenuated in the heparin groups. Histological changes consisting of cellular infiltrates, lung edema, congestion, and cast formation were reduced by heparin. These data suggest that nebulized inhaled heparin is a beneficial therapy for sepsis-induced ALI.

Delayed rectifier potassium channels contribute to the depressed pulmonary artery contractility in pneumonia.

We investigated the role of K(+) channels in the attenuated pulmonary artery (PA) contractility characteristic of acute Pseudomonas pneumonia. Contractility of PA rings from the lungs of control or pneumonia rats was assessed in vitro by obtaining cumulative concentration-response curves to the contractile agonists KCl, phenylephrine, or PGF(2 alpha) on PA rings before and after treatment with K(+) channel blockers. In rings from pneumonia rats, paxilline (10 microM), tetraethylammonium (2 mM) (blockers of large-conductance Ca(2+)-activated K(+) channels), and glybenclamide (ATP-sensitive K(+) channel blocker, 80 microM) had no significant effect on the attenuated contractile responses to KCl, phenylephrine, and PGF(2 alpha). However, 4-aminopyridine (2 mM), a blocker of voltage-gated K(+) channels (delayed rectifier K(+) channel) reversed this depressed contractility. Therefore, large-conductance Ca(2+)-activated K(+) and ATP-sensitive K(+) channels do not contribute to the attenuated PA contractility observed in this model of acute pneumonia. In contrast, 4-aminopyridine enhances contraction in PA rings from pneumonia lungs, consistent with involvement of a voltage-gated K(+) channel in the depressed PA contractility in acute pneumonia. Unraveling the precise mechanism of attenuated contractility in pneumonia could lead to innovative therapies for the pulmonary vascular abnormalities associated with this disease.

Person-to-Person Transmission of Pseudomonas Pneumonia in the Community

Person-to-Person Transmission of Pseudomonas Pneumonia in the Community

Person-to-Person Transmission of Pseudomonas Pneumonia in the Community

Person-to-Person Transmission of Pseudomonas Pneumonia in the Community

Role of interleukin-1 in the pulmonary immune response during Pseudomonas aeruginosa pneumonia.

Pneumonia is associated with elevated concentrations of the proinflammatory cytokine interleukin (IL)-1 in the pulmonary compartment. To study the role of IL-1 in the pathogenesis of Pseudomonas pneumonia, IL-1 receptor type 1 gene-deficient (IL-1R -/-) mice and wild-type mice were intranasally inoculated with Pseudomonas aeruginosa. The absence of the IL-1 signal attenuated the outgrowth of Pseudomonas in lungs, as reflected by an increasing number of colony-forming units (cfu) during Pseudomonas pneumonia in wild-type mice and a concurrently decreasing number of cfu during pulmonary infection in IL-1R -/- mice (P < 0.05, IL-1R -/- mice vs. wild-type mice). Influx of neutrophils was decreased in bronchoalveolar lavage fluids in IL-1R -/- mice compared with wild-type mice. Similarly, lung levels of cytokines (tumor necrosis factor-alpha, IL-6) and chemokines (macrophage inflammatory protein-2 and KC) were lower in IL-1R -/- mice 24 h postinoculation. Consistent with results obtained in IL-1R -/- mice, treatment of wild-type mice with IL-1R antagonist also diminished outgrowth of Pseudomonas when compared with wild-type mice treated with vehicle (P < 0.05). These results demonstrate that an absence or reduction in endogenous IL-1 activity improves host defense against Pseudomonas pneumonia while suppressing the inflammatory response.

Organophosphorous poisoning with intermediate syndrome

Organophosphorous poisoning with intermediate syndrome

Neumotórax en pacientes infectados por el virus de inmunodeficiencia humana

Patients with HIV who develop pneumothorax have been previously described. Pneumocystis carinii pneumonia (PCN) is the leading cause of this complication, but infection by other pulmonary microorganism, inhaled pentamidine therapy and lung invasive manoeuvres have also been associated with pneumothorax in HIV infected patients. We review the most relevant clinical aspects of pneumothorax in HIV-infected persons, gathered in our hospital along eight years, before HAART therapy was started. During this time, 97 patients with PCN were diagnosed and 148 patients received prophylaxis with inhaled pentamidine. Only 14 episodes of pneumothorax in 13 patients, were recorded. In ten occasions pneumothorax was related to pulmonary invasive manoeuvres, pulmonary infections were found in three and was considered spontaneous in one. The pulmonary invasive manoeuvres were: subclavia vein catheterisation in six cases (one of them was diagnosed of proved PCN and the other has pneumococcal pneumonia); transbronchial biopsy in one patient (also with proved PCN), knife chest trauma in two cases and after fine needle aspiration of an axillary lymph node in one patient. The pulmonary infections associated with pneumothorax in three patients were: proved PCN (this patient was the only one in the group with inhaled pentamidine prophylaxis who developed pneumothorax), active pulmonary infection by mycobacterium tuberculosis and Pseudomonas aeruginosa pneumonia. A drainage chest tube was placed in 12 patients with complete resolution in nine. In the other two patients pleurodesis was necessary and surgical repair was carried out in the other one (who had pulmonary tuberculosis). During the follow up six patients died (median time to death: 7 months). Among patients who died, five had pulmonary infections when the pneumothorax was diagnosed: PCN in three cases, pulmonary tuberculosis and pseudomonas pneumonia in the other two; all of them with less than 100 CD4 lymphocytes. Pneumothorax is frequent in HIV-infected patients with PCN, but other lung infections and, above all pulmonary invasive manoeuvres, can cause this complication. In our experience, HIV-infected patients who develop pneumothorax have a bad prognosis.

Aerosolized Amikacin in the Treatment of Pseudomonas Pneumonia in the Nursing Home Setting

Studies have shown that aerosolized aminoglycosides represent a safe and effective means of treating pneumonia due to Pseudomonas sp. Aerosolized aminoglycosides have been shown to improve clinical outcome, with less risk of nephrotoxicity relative to parenteral aminoglycosides. Apparently, less drug resistance is associated with the use of aerosolized aminoglycosides. Cost factors favor aerosolized delivery methods. The full recovery experienced by the patient in this case study suggests that aerosolized amikacin may be a safe, efficacious, and cost-effective means of treating pseudomonal pneumonia in geriatric patients. Controlled clinical trials should be conducted to further investigate this treatment regimen.