Tags: Gatifloxacin

Mycoplasma Pneumoniae Infection & Disease

Infected humans are the only source of M pneumoniae organisms for transmission to new susceptible hosts. M pneumoniae is spread from one individual to another by respiratory droplets produced by coughing. Individuals at any age can be infected and develop disease, but those between the ages of 5 and 20 years are most often affected. M pneumoniae is a leading cause of pneumonia in school-aged children and young adults — especially those in military and college populations.

Enterococci

Enterococci are able to grow and survive under harsh conditions and can be found in soil, food, water, and a wide variety of animals. The major habitat of these organisms is the gastrointestinal tract of humans and other animals, where they make up a significant portion of the normal gut flora. Most enterococci isolated from human stools are E faecalis, although E faecium are also commonly found in the human gastrointestinal tract. Small numbers of enterococci are occasionally found in oropharyngeal and vaginal secretions and on the skin, especially in the perineal area.

Enterococci: Clinical Syndromes

Urinary tract infections, including uncomplicated cystitis, pyelonephritis, prostatitis, and perinephric abscess, are the most common type of clinical infections produced by enterococci (Box 1). Most enterococcal urinary tract infections are nosocomial and are associated with urinary catheterization or instrumentation. Nosocomial enterococcal bacteremias are commonly polymicrobial. Portals of entry for enterococcal bacteremia include the urinary tract, intra-abdominal or pelvic sources, wounds (especially burns, decubitus ulcers, and diabetic foot infections), intravascular catheters, and the biliary tree.

Deciding On Hospital Admission In Acute Pneumonia

The Pneumonia Patient Outcome Research Team developed useful criteria called the pneumonia severity index for assessing pneumonia severity; however, that index proved to be complex and difficult to use. A simpler index called the CURB-65 (confusion, urea nitrogen, respiratory rate, blood pressure, age 65 years or older) has been shown to have sensitivity and specificity nearly equal to that of the pneumonia severity index. Both indexes can be used to guide decisions on admission to a hospital ward or intensive care unit. As shown in Figure 4.5, patients with a score of 0 or 1 can be treated as outpatients; those with a score of 2 or more warrant hospitalization.

Specific Causes Of Acute Community-Acquired Pneumonia

Great overlap occurs among the clinical manifestations of the pathogens associated with acute community-acquired pneumonia. However, constellations of symptoms, signs, and laboratory findings serve to narrow the possibilities. By developing an ability to focus on a few pathogens or to identify a specific pathogen, clinicians can better predict the clinical course of pneumonia and can narrow antibiotic coverage. Pathogenic strains of S. pneumoniae have a thick capsule that prevents PMN binding and that blocks phagocytosis.

Anti-Infective Agent Dosing

The characteristics that need to be considered when administering antibiotics include absorption (when dealing with oral antibiotics), volume of distribution, metabolism, and excretion. These factors determine the dose of each drug and the time interval of administration. To effectively clear a bacterial infection, serum levels of the antibiotic need to be maintained above the minimum inhibitory concentration for a significant period. For each pathogen, the minimum inhibitory concentration is determined by serially diluting the antibiotic into liquid medium containing 104 bacteria per millihter.

Specific Anti-Infective Agents

Clinicians should be familiar with the general classes of antibiotics, their mechanisms of action, and their major toxicities. The differences between the specific antibiotics in each class can be subtle, often requiring the expertise of an infectious disease specialist to design the optimal anti-infective regimen. The general internist or physician-in-training should not attempt to memorize all the facts outlined here, but rather should read the pages that follow as an overview of anti-infectives. The chemistry, mechanisms of action, major toxicities, spectrum of activity, treatment indications, pharmacokinetics, dosing regimens, and cost are reviewed.

Urinary Tract Infections and Prostatitis

A urinary tract infection is defined as the presence of microorganisms in the urine that cannot be accounted for by contamination. The organisms have the potential to invade the tissues of the urinary tract and adjacent structures.

Treatment of Tuberculosis

Recommended Drug Regimens for Treatment of Latent Tuberculosis Infection. Drug Regimens for Culture-Positive Pulmonary Tuberculosis Caused by Drug-Susceptible Organisms. Doses of Antituberculosis Drugs for Adults and Children. Tuberculous meningitis and Extrapulmonary disease.

Skin and Soft Tissue Infections

Impetigo is a superficial skin infection that is seen most commonly in children. It is highly communicable and spreads through close contact. Most cases are caused by S. pyogenes, but S. aureus either alone or in combination with S. pyogenes has emerged as a principal cause of impetigo.