Tags: Bone infections

Other Mycobacteria

The increasingly relative importance of the atypical mycobacteria, many of which are ubiquitous in the environment, was recognized with the decline in tuberculous disease. Generally, atypical mycobacteria are unusual causes of disease in patients who are immunocompetent but can in immunocompromised hosts such as AIDS and cancer patients.

Important Anaerobes

Anaerobic bacteria are the predominant component of the normal microbial flora of the human body. The following sites harbor the vast majority of them:

Important Anaerobes: Clinical Syndromes

Box 1 summarizes different clinical syndromes associated with anaerobic bacteria. The sections that follow describe the various syndromes, including clinical findings. For some syndromes, specific diagnosis and treatment information is included as well.

Other Bacillus Species

Bacillus species other than B anthracis are found in soil, decaying organic matter, and water, but they are rare causes of disease. Risk factors associated with Bacillus infection include the presence of intravascular catheters, intravenous drug use, sickle cell disease, and immunosuppression — particularly corticosteroid use, transplantation, AIDS, and neutropenia secondary to chemotherapy.

Osteomyelitis

Osteomyelitis is divided into two subcategories based on the acuity of onset. Acute osteomyelitis, more commonly seen in children, is associated with sudden onset of bony pain, fever, and malaise. Acute disease is often the result of seeding of the bone during S aureus bacteremia, with the most common anatomic locations corresponding to highly vascularized osseous areas such as the metaphyses of long bones. Chronic osteomyelitis is a more indolent process, characterized by low-grade fevers and chronic nonhealing ulcers or draining sinus tracts in the skin overlying the infected bone.

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.

Antituberculosis Agents General Statement

Antituberculosis agents are antibiotics and synthetic anti-infectives used in the treatment of tuberculosis and other diseases caused by organisms of the genus Mycobacterium. Isoniazid, rifampin, ethambutol, and pyrazinamide are the drugs used most frequently in the treatment of tuberculosis and are considered first-line agents for use in antituberculosis regimens.

Tobramycin Sulfate

Commercially available tobramycin solution for oral inhalation is administered via nebulization in the management of bronchopulmonary Pseudomonas aeruginosa infections in cystic fibrosis patients 6 years of age or older. Use of tobramycin oral inhalation solution can be considered for suppressive therapy in cystic fibrosis patients colonized with Ps. aeruginosa if they are 6 years of age or older and have a forced expiratory volume in 1 second (FEV1) that is 25-75% of the predicted value. At baseline, the FEV1 in all study patients was 25-75% of the predicted value.

Gentamicin Sulfate

Gentamicin is an aminoglycoside antibiotic and has a bactericidal action against many Gram-negative aer-obes and against some strains of staphylococci.