Nosocomial pneumococcal bacteremia.

In five years we studied 56 episodes of pneumococcal bacteremia. Twenty-three (41%) were nosocomial and 33 (59%) community acquired. Most of our patients were elderly men with multiple underlying diseases; however, those patients with nosocomial infections had a significantly higher incidence of malignant neoplasms (57% vs 24%), poor functional status (70% vs 25%), and ultimately fatal underlying disease (61% vs 21%). Alcoholism was more common among the patients with community-acquired bacteremia (45% vs 17%). Nosocomial infections carried a significantly higher overall mortality (73.9% vs 45.4%). The mortality directly related to the pneumococcal bacteremia was also higher (52% vs 39%), but not significantly. Most of the isolated strains were serotypes present in the new pneumococcal vaccine, which only one study patient had received. Mixed pneumococcal bacteremia with gram-negative bacilli was more frequent in nosocomial infections. Streptococcus pneumoniae can be a nosocomial pathogen in elderly, debilitated patients. Pneumococcal vaccination should be incorporated in a hospital-based prevention program for high-risk patients.

Respiratory infections caused by Branhamella catarrhalis. Selected epidemiologic features.

PURPOSE: This work reviewed existing literature pertaining to the epidemiologic aspects of respiratory tract infections caused by Branhamella catarrhalis, examined certain epidemiologic features of B. catarrhalis infections occurring at this facility, and identified relevant areas in need of further study. PATIENTS AND METHODS: Literature dealing with the epidemiology of B. catarrhalis infections was reviewed. Records in this Veterans Administration hospital microbiology laboratory were reviewed and all B. catarrhalis isolates and pure cultures of Hemophilus influenzae and Streptococcus pneumoniae were noted for the January 1986 to June 1989 study period. RESULTS: B. catarrhalis is now recognized as a disease-causing pathogen that is particularly noted for its association with acute otitis media in children and lower respiratory tract infections in adults with underlying cardiopulmonary disease. It was recovered from 2.7 percent of all respiratory specimens submitted over a 42-month period at this Veterans hospital. When compared with H. influenzae and S. pneumoniae, B. catarrhalis was found to be the second most commonly isolated respiratory pathogen. It was frequently found in pure culture (53 percent) or in combination with H. influenzae, gram-negative bacilli, or S. pneumoniae. The seasonal recovery of B. catarrhalis was apparent for the November to May period compared with the June to October period (p less than 0.001). CONCLUSION: B. catarrhalis has emerged as a major respiratory pathogen in pediatric and adult patient populations. There is a distinct seasonal pattern associated with its recovery and reasons for this are unclear. Prevalence studies aimed at identifying colonization rates among "low" and "high" risk groups are needed. The availability of restriction endonuclease analysis as a typing system for B. catarrhalis should favorably impact upon future epidemiologic studies. Many B. catarrhalis isolates produce beta-lactamase, and therapeutic options must reflect this.

Klebsiella oxytoca isolates in a general hospital.

Primary infections caused by Klebsiella species are uncommon, but the organism is an important nosocomial pathogen. We report the predisposing factors, clinical features and outcome of 44 hospitalized patients in whom Klebsiella oxytoca was isolated. Twenty-one (48%) isolates were community-acquired and 23 (52%) were considered nosocomial in origin. Most of the patients were elderly males with serious underlying diseases. There were significant differences between those patients who acquired Klebsiella oxytoca in the hospital and in the community. Nosocomially acquired organisms were associated with a higher mortality (52% vs. 24%) (p less than 0.05), a higher incidence of infection vs. colonization (83% vs. 57%) (p less than 0.05), and a higher percentage of cases of pneumonia (43% vs. 19%) (p less than 0.05). The clinical features, the hospital service and the patients' underlying diseases were similar when patients who died and those who survived were compared. Patients who died were exposed to antibiotics more often prior to the positive culture with K. oxytoca (p less than 0.05). K. oxytoca is a significant pathogen in hospitalized elderly patients. It is likely to cause infections, especially pneumonia, and carry a high mortality. The organism can become endemic within the hospital setting with continued carriage and nosocomial spread.

Nosocomial infections in long-term facilities.

We studied the incidence and prevalence of hospital-acquired infections in our intermediate-care units and the Nursing Home Care Unit at the Veterans Administration Medical Center, Johnson City, TN over a 4-year period (1980 through 1983). The global infection rate was 3.86 per 1,000 patient care days. The lower respiratory tract was the most common site of infection, followed by urinary tract infections, skin infections, bacteremia, wound infections, and infections at other sites. The prevalence study conducted by monthly visits over a 1-year period showed similar results. All of our patients were elderly males with multiple underlying diseases and poor performance status. The high incidence of nosocomial infections in chronic-care facilities relates to the poor functional assessment of the patients, which may increase the susceptibility of these patients to develop infections, mainly lower respiratory and cutaneous infections.