Acute exacerbation of chronic bronchitis. Guidelines for antibiotic selection.

An acute exacerbation of chronic bronchitis (AECB) is frequently caused by viral infection. Because of the impairment of mucociliary clearance, secondary bacterial infection is likely to ensue. Haemophilus influenzae, Streptococcus pneumoniae, and Moraxella catarrhalis account for about 50% of all episodes of AECB. The best approach to antibiotic selection for bacterial exacerbations is stratification by exacerbation type, patient type, or antibiotic type.

Novel cost-effective approaches to the treatment of community-acquired infections.

OBJECTIVE: To review approaches to the diagnosis and treatment of patients with community-acquired infections. INTRODUCTION: Dramatic changes in the antibiotic susceptibility of pathogens commonly associated with community-acquired infections have occurred during the past decade. DISCUSSION: Changes in the antibiotic sensitivity profile of Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis that have occurred over the past several years have required modifications in empiric antibiotic selections for infections due to these pathogens. The most profound changes have occurred with S. pneumoniae, which has shown significant resistance to beta-lactams by means of alteration of one or more of the five important penicillin-binding proteins. Many of these organisms have become resistant to other classes of antibiotics; some are sensitive only to vancomycin. H. influenzae and M. catarrhalis have developed resistance primarily by production of beta-lactamase. CONCLUSIONS: The antibiotic selection process for the treatment of community-acquired pneumonia relates to the site of infection and, in many cases, the in vitro sensitivity testing results or known patterns in a given geographic area.

Cellulitis of the breast as a complication of breast-conserving surgery and irradiation.

Breast-conserving therapy (BCT) has become a standard treatment option for patients with early-stage breast cancer. We have observed cellulitis of the treated breast as a complication occurring before, during, and after breast irradiation. The cases of five women (median follow-up, 28 months; range, 24-65 months) who developed cellulitis before (n = 1), during (n = 2), or after (n = 2) breast irradiation were reviewed. A consecutive series of BCT patients at Emory University was reviewed to determine the incidence of this complication. Four of five women had an axillary dissection, yielding a median of 14 negative lymph nodes (range, 6-22 nodes). Two of four patients developed axillary seromas requiring aspiration. In these four patients, only the breast was irradiated. A fifth patient had no axillary dissection and had breast and supraclavicular/axillary irradiation. The median whole breast dose was 50 Gy (range, 46-50.4 Gy). The clinical features of cellulitis included erythema, edema, tenderness, and warmth in all patients. Cellulitis was a relapsing problem for four of the five patients. The incidence of this complication in our series of BCT patients was approximately 1%. Cellulitis in the ipsilateral breast can be a relapsing complication of BCT and can be seen before, during, or after breast irradiation. Axillary seromas and aspiration seem to indicate a subset of patients at risk of early cellulitis. Late cellulitis may be caused by a variety of factors related to modifications of vascular and skin integrity by surgery and radiotherapy. Prompt diagnosis and appropriate antibiotic therapy is recommended. This problem need not interrupt a course of breast irradiation, and does not necessarily lead to a poor cosmetic result.

Pentamidine isethionate in the treatment of Pneumocystis carinii pneumonia.

The chemistry, antiprotozoal activity, pharmacology, clinical efficacy, adverse effects, dosage, administration, and hospital formulary considerations of pentamidine isethionate are reviewed. Pentamidine, an aromatic diamidine, has been used since the 1940s to treat a variety of protozoal infections. It is now most commonly administered in the treatment of Pneumocystis carinii pneumonia (PCP). It is generally not metabolized, and it is stored or bound to tissue and excreted slowly as the parent compound. Pentamidine is clearly effective in the treatment of PCP; however, the high incidence of adverse reactions associated with the drug led to the use of trimethoprim-sulfamethoxazole (TMP-SMX) as the first-line agent for PCP. Recent studies have reported a high incidence of adverse reactions, including leukopenia and hepatotoxicity, associated with the use of TMP-SMX therapy for PCP in patients with the acquired immunodeficiency syndrome (AIDS). The severity and frequency of these reactions suggest a possible new role for pentamidine in patients with AIDS who have PCP. The recommended intramuscular and intravenous dosage of pentamidine isethionate for adults and children is 4 mg/kg/day for 14 days. Intramuscular administration is recommended; however, intravenous administration is a safe alternative if the dose is infused over a 60-minute period. Pentamidine isethionate has specific application in the treatment of PCP as a second-line agent reserved for patients who cannot tolerate TMP-SMX.

An unusual case of North American blastomycosis.

A patient with a laryngeal tumor first diagnosed as squamous cell carcinoma was subsequently found to have North American blastomycosis. Diagnosis of this condition eventuated in eradication of the lesion as well as removal of a tracheostomy, which was thought to be permanent.

Sternal osteomyelitis and mediastinitis after open-heart operation: pathogenesis and prevention.

Sternal osteomyelitis and mediastinitis caused by Pseudomonas cepacia developed in a patient undergoing coronary artery bypass two weeks after the operation. P. cepacia bacteremia from a contaminated pressure transducer had preceded and probably caused the chest infection. While other authors have suggested that postoperative sternal osteomyelitis and mediastinitis result from local wound contamination, this case suggests the importance of bacteremia as a cause of such gram-negative infections. Since patients undergoing open-heart operation are exposed to many sources of bacteremia, prevention of severe postoperative chest infections may depend in large part on careful preoperative evaluation of each patienc antibiotic regimens, and, as shown in this patient, on very thorough periodic review of equipment sterilization and intravascular monitoring practices.