Nancy Misri Khardori

Immunotherapies in infectious diseases.

The development of an infection involves interplay between the hosts immune system and the virulence of the infecting microorganism. The traditional treatment of an infection involves antimicrobial chemotherapy to kill the organism. The use of immunotherapies in infections includes treatment options that modulate the immune response and can lead to control of infections. These therapies are expected to become more important therapeutic options with the increase in infections due to multidrug-resistant organisms and the increasing number of immunocompromised patients.

Necrotizing Soft-Tissue Infections

NSTI is a life-threatening, surgical, and medical emergency. Clinical presentation, at least in the initial phase, can be misleading. Various studies have shown that delay in surgical debridement is associated with increased mortality. A high index of suspicion is important in early recognition and in instituting prompt therapy without delay. Early diagnosis, aggressive surgical debridement, aggressive supportive care, and optimal presumptive antibiotic therapy significantly improve morbidity and mortality associated with NSTIs.

Cardiac Emergencies: Infective Endocarditis, Pericarditis, and Myocarditis

Cardiac infections presenting as emergencies include complications of infective endocarditis, including congestive heart failure, chordae tendinae rupture, cardiac arrhythmias, and embolic phenomenon; acute pericarditis, including cardiac tamponade; and acute myocarditis presenting with malignant cardiac arrhythmias or congestive heart failure. Most of these emergent infectious disease manifestations of the cardiovascular system have a good prognosis if diagnosed early and managed appropriately. Newer diagnostic modalities and combined treatment guidelines are available from the European Society of Cardiology and the American Heart Association.

Overwhelming Capnocytophaga canimorsus infection in a patient with asplenia

Patients with asplenia are prone to overwhelming infections due to encapsulated organisms. We report a 62-year-old man presenting with fever and weakness. His medical history was significant for splenectomy and owning a dog as pet. The patient on examination had evidence of animal bite and scratch marks on his lower extremity and developed dry gangrene of multiple digits of his upper extremity soon after admission. The patients initial blood cultures were positive for Gram-negative rods, but no organism was identified. Capnocytophaga canimorsus was the suspected organism and the patients antibiotics were tailored accordingly, with good clinical recovery. The patient’ blood cultures finally grew C canimorsus on day 20 for which the patient had already been treated with prior clinical judgement. Physicians should be aware of this organism in the setting of sepsis in patients with asplenia and use appropriate antibiotics until further results are obtained.

Immunotherapy in clinical medicine: historical perspective and current status.

In humans, the immune system is a complex organ system involving cells and soluble mediators whose function is, essentially, protection. However, disequilibrium in this intricate system leads to disease in itself. To modulate these responses, immunotherapy is now the primary or adjunct treatment of many diseases. In addition, immunologic tests now diagnose several diseases.

Legionnaire’s Disease and Immunosuppressive Drugs

Immunosuppressive agents predispose patients to legionnaires disease. Patients receiving tumor necrosis factor antagonists are generally not severely immunocompromised by the underlying disease. In patients with malignancy receiving immunosuppressive therapies, it is difficult to balance the underlying disease versus the therapy used. Transplant recipients are often on multiple drugs, including immunosuppressants. It seems that immunosuppressive drugs add to the risk for legionella infection. The index of suspicion should be high for legionella infection early during a compatible clinical syndrome. The control of Legionella species and prevention of transmission should be the foremost goal in protecting susceptible populations from Legionnaires disease.

Intra-abdominal and Pelvic Emergencies

The diversity in intra-abdominal/pelvic infections is more than any other organ system. Several clinical scenarios can end up in intra-abdominal infections. The common causes include penetrating abdominal trauma, abdominal surgery, diverticulitis, appendicitis, pancreatitis, biliary disease, perforated viscus, and primary peritonitis. Intra-abdominal infections can masquerade as fever of obscure origin or as dysfunction of neighboring organs, such as lower lobe pneumonia related to a subphrenic abscess or an abscess causing small bowel obstruction. An urgent surgical intervention is the mainstay of the management of serious intra-abdominal infections.

Mycobacteria and biological response modifiers: two sides of the relationship.

With increasing use of biological response modifiers (BRMs) for various systemic inflammatory diseases there is a need to be vigilant about complications with the use of these therapies. It is important to have appropriate screening for the infections in patients requiring BRMs. However, many studies have reported benefits of certain BRMs in the treatment of infections such as tuberculosis as adjuncts. Continued research and technical advances in immunogenetics helps understand complex mechanisms in the usage of the BRMs. This article summarizes the different aspects of the relationship between mycobacterial infections and the use of various BRMs for inflammatory conditions.

Efficacy of selected biocides in the decontamination of common nosocomial bacterial pathogens in biofilm and planktonic forms.

The efficacy and use of biocides to eliminate pathogens in the health care environment are based on their testing against planktonic bacteria. In the environment, bacteria exist in biofilms, as they do on medical devices, and as planktonic or viable non-culturable forms as well. This work aimed to evaluate the efficacy of four biocides against the biofilm and planktonic phases of nine common nosocomial bacteria. The bactericidal activity of the biocides against bacteria in the planktonic form was assessed using a broth microdilution technique. The killing activity of the biocides against biofilms was evaluated using cells grown on polyethylene tubes under a dynamic flow-cell system that was designed for biofilm growth. All biocides completely killed the planktonic bacteria at all concentrations; however, they did not eradicate the biofilms of the same pathogens. Our study highlights the need for an alternative strategy, one that utilizes chemicals that have been tested to disrupt or prevent biofilm growth, in order to enhance current disinfection practice.

The Mighty World of Microbes: An Overview

The world of microbes on our planet is vast and diverse. This includes the normal bacterial flora present on the skin and mucous membranes of humans. The human microbiome project (HMP) was launched by NIH in 2007 as a part of a road map for medical research. The HMP serves as a template for researchers who are studying more than 1,000 microbial genomes with a focus on their role in health and disease. The study samples have been derived from five human body regions that are known to be inhabited by microbial flora. These include the gastrointestinal tract, female urogenital tract, mouth, nose, and skin. The techniques being used include finger printing, sequencing, dynamic range, and comparison of multiple samples. It is now well accepted that there are more microbial cells than human cells in the human body. Just the gastrointestinal tract harbors more than tenfold microbial cells than the number of human cells in the entire body. The understanding of the relationship between microbes and humans is at best rudimentary at this point in time. Similarly, the relationship between humans and microbes in the environment and environmental surfaces is poorly understood except for a few pathogenic microbes.