Edward J. Young

Perspectives for the Treatment of Brucellosis in the 21st Century: The Ioannina Recommendations

The authors provide evidence-based guidance on treating human brucellosis, and discuss the future clinical trials that would help address the controversies surrounding treatment.

The current spectrum of Staphylococcus aureus infection in a tertiary care hospital.

Staphylococcus aureus remains a prominent cause of community- and hospital-acquired infection. This study reviewed 162 cases of S. aureus infection occurring in 120 adults who were hospitalized at a Veterans Affairs Medical Center and referred for consultation to the Infectious Disease Service. There were 37 cases of skin and soft tissue infection, 5 pyomyositis, 34 osteomyelitis, 13 septic arthritis, 19 pneumonia, 3 empyema, 5 pyelonephritis, 37 vascular infection, 3 epidural abscess, and 6 miscellaneous infections. Bacteremia was documented in 56 of 119 (47%) cases in which blood cultures were obtained, indicating the serious nature of the infections in many cases. Staphylococcus aureus is widely prevalent in healthy persons. Given its ubiquity and the capacity to cause a broad array of infections, an effective host response must play an important role in preventing infection. This host response is immunologically nonspecific, in that it depends upon the effectiveness of mechanical barriers to invasion and, once invasion takes place, the interaction of PMN, complement, and antibody that is probably present in serum of all immunologically competent adults rather than sensitization of B or T lymphocytes by any identifiable antigens specific to S. aureus. Analysis of the present cases calls attention to S. aureus as an opportunistic pathogen, 1 that only infrequently causes serious infection in otherwise healthy persons. Nearly every patient in this series had 1 or more medical condition thought to predispose to infection; 279 such conditions were identified, representing an average of 2.3 per person. A break in the natural barrier to infection was also present in the majority of cases, for example, trauma, wound, or pre-existing decubitus ulcer in skin and soft tissue infections; endotracheal tube in pneumonia; and a catheter bypassing urethra or skin in urinary and vascular infections, respectively. The tendency for patients to be infected with S. aureus repeatedly (mean number of infections, 1.4 per patient) reflects the chronicity of many predisposing factors and, perhaps, of colonization as well. Staphylococcus aureus has a special predilection to cause infections involving prosthetic devices, perhaps related to its affinity for fibronectin, laminin, and other serum proteins that can mediate attachment to foreign material; 46 of 162 (28%) infections were associated with the presence of a foreign body. Such infections are difficult to eradicate with antibiotic therapy alone, perhaps because of a change in the metabolic state of adherent bacteria, and removal of the foreign body is generally required for cure.(ABSTRACT TRUNCATED AT 400 WORDS)

Haemophilus parainfluenzae infective endocarditis.

Seven young to middle-aged patients with Haemophilus parainfluenzae endocarditis are reported. Three patients had underlying heart disease and three patients had recent events predisposing for endocarditis. The clinical presentation was subacute or acute and new pathologic murmurs were uncommon. Diagnosis was prolonged because of difficulties in isolating the organism. Routine subculturing of blood cultures to chocolate agar with incubation in CO2 is recommended. A prominent complication, occurring in six patients, was major arterial occlusion secondary to emboli. Antibiotic control of infection was difficult and best achieved by the concomitant administration of ampicillin and gentamicin. Killing curves proved useful in assessing antibiotic efficacy. There were two medical failures and one death in the series. It appears H. parainfluenzae endocarditis is characterized by distinctive clinical features, difficult in vitro isolation of the organism, and the necessity for combination antibiotic therapy.

Thrombocytopenic purpura associated with brucellosis: report of 2 cases and literature review.

Mild hematologic abnormalities are common in the course of human brucellosis; however, they generally resolve promptly with treatment of the disease. Occasionally, thrombocytopenia is severe and can be associated with bleeding into the skin (purpura) and from mucosal sites. We describe 2 patients infected with Brucella melitensis who presented with thrombocytopenic purpura, and we review 41 additional cases from the literature. Patients ranged in age from 2 to 77 years, and both sexes were affected equally. In the majority of cases, examination of the bone marrow revealed abundant megakaryocytes. Possible mechanisms involved in thrombocytopenia include hypersplenism, reactive hemophagocytosis, and immune destruction of platelets. Recognition of this complication is essential, since hemorrhage into the central nervous system is associated with a high mortality rate.

Implementation of a methicillin-resistant Staphylococcus aureus (MRSA) prevention bundle results in decreased MRSA surgical site infections

BACKGROUND Methicillin-resistant Staphylococcus aureus (MRSA) surgical site infections (SSIs) increase morbidity and mortality. We examined the impact of the MRSA bundle on SSIs. METHODS Data regarding the implementation of the MRSA bundle from 2007 to 2008 were obtained, including admission and discharge MRSA screenings, overall MRSA infections, and cardiac and orthopedic SSIs. Chi-square was used for all comparisons. RESULTS A significant decrease in MRSA transmission from a 5.8 to 3.0 per 1,000 bed-days (P < .05) was found after implementation of the MRSA bundle. Overall MRSA nosocomial infections decreased from 2.0 to 1.0 per 1,000 bed-days (P = .016). There was a statistically significant decrease in overall SSIs (P < .05), with a 65% decrease in orthopaedic MRSA SSIs and 1% decrease in cardiac MRSA SSIs. CONCLUSION Our data demonstrate that successful implementation of the MRSA bundle significantly decreases MRSA transmission between patients, the overall number of nosocomial MRSA infections, and MRSA SSIs.

Infections in Prosthetic Devices

Infection in prosthetic devices is a rare but potentially serious complication of prosthesis implant surgery. Infections associated with a variety of permanently implanted devices are reviewed in the context of recent knowledge of the host-prosthesis interaction.

A Nosocomial Outbreak of Norovirus Infection Masquerading as Clostridium difficile Infection

Noroviruses (NoVs) are increasingly being recognized as important enteric pathogens. At a university-based hospital, we investigated a nosocomial outbreak of NoV infection that was originally attributed to Clostridium difficile. We describe here the unique challenges of the identification of NoVs as the true etiologic pathogen in an outbreak occurring in a health care setting, where C. difficile infection is endemic, as well as the important lessons learned.

Disseminated Actinomyces meyeri infection resembling lung cancer with brain metastases.

Thoracic actinomycosis can resemble bronchogenic carcinoma in its clinical presentation and radiographic appearance. We report a case of pulmonary actinomycosis caused by Actinomyces meyeri in which hematogenous dissemination caused multiple brain abscesses resembling metastatic lung cancer. The correct diagnosis was made by thin-needle aspiration of a pleura-based lung mass. The pathogen isolated was further identified with the use of 16S rDNA sequencing. Antibiotic therapy resulted in rapid improvement of the lung lesion; however, the brain lesions required surgical drainage. Antibiotics were continued for more than a year before magnetic resonance images showed complete resolution of the cerebral abscesses.

Liver histology of acute brucellosis caused by Brucella melitensis

As a major organ of the mononuclear phagocytic system, the liver is probably involved in all cases of brucellosis. In this prospective study, liver slides prepared from percutaneous liver biopsy samples of 20 patients with clinical and laboratory evidence of acute brucellosis due to Brucella melitensis were examined for the presence or absence of granulomas by pathologists in Iran and the United States. Nineteen men and one woman ranging in age from 14 to 62 years were studied. All patients had clinical signs and symptoms compatible with acute brucellosis, and all had significantly elevated titers of antibodies to Brucella in their serum. Liver function tests were mildly elevated in 11 (55%) cases, and C-reactive protein was positive in 15 (65%) patients. Thirteen (65%) patients had blood cultures positive for B melitensis. Iranian and American pathologists reported granulomas in 3 (15%) and in 4 (20%) cases, respectively. There was agreement between Iranian and American pathologists in 17 (85%) cases. The most prevalent findings were mild portal or lobular lymphocytic inflammation (16 cases). Two cases revealed noncaseating epithelioid granulomas, and 2 had microgranulomas. The results show that all patients had microscopic evidence of liver involvement. The predominant histologic finding was mild portal or lobular inflammation with lymphocytes. Granulomas were present in only 4 cases.

Purulent Pericarditis Due to Neisseria mucosa

A 51-year-old man with chronic renal failure developed purulent pericarditis. Cultures of pericardial fluid and tissue grew Neisseria mucosa .