Israel Medical Association Journal

Background: Nasal colonization with methicillin-resistant Staphylococcus aureus in the community is being increasingly reported, but there is a general lack of data on MRSA[1] colonization in children in chronic care institutions and on colonization rates in Israeli children.

Objectives: To define the rate of MRSA nasal colonization in a generally healthy pediatric population in Jerusalem, to compare it with that of children in chronic care institutions, to define risk factors for colonization, and to compare community and hospital-acquired MRSA strains.

Methods: Anterior nares culture for the presence of methicillin-sensitive and methicillin-resistant S. aureus was taken from 831 healthy children attending primary pediatric clinics or emergency department and 118 children hospitalized in three chronic care institutions in Jerusalem.

Results: Of the 831 healthy children, 195 (23.5%) were colonized with S. aureus, as compared to 43 of 118 (36.4%) chronically institutionalized children (P < 0.005). Five of the 195 S. aureus isolates from healthy children (2.6%) were MRSA, as compared to 9 of 43 (21%) from chronically institutionalized children (P < 0.001). Older age and a family member who is a healthcare worker were associated with S. aureus colonization in the population of healthy children, and older age was associated with MRSA colonization in the chronically institutionalized children. The antibiotic susceptibility pattern was similar for both groups, and pulsed field gel electrophoresis of the isolates showed a wide and random distribution in both groups.

Conclusions: MRSA colonization in the studied pediatric community in Jerusalem was very low, whereas that of patients hospitalized in chronic care institutions was significantly higher. In the small number of isolates detected, no significant differences were found in antibiotic susceptibility or PFGE[2] pattern between hospital-acquired and community-acquired strains.

Background: Recent studies have suggested a possible association between Chlamydia pneumoniae infection and coronary heart disease.

Objectives: To determine titers of antibodies to Chlamydia pneumoniae in patients with acute  myocardial infraction compared with titers in several control groups.

Methods: This prospective case-control study investigated 209 individuals. We assessed the serum IgG antibody titers to Chlamydia pneumoniae in 57 consecutive patients admitted with AMI to our intensive coronary care unit during a 4 month period. A serum sample was drawn upon admission after 6 weeks. Results were compared with those of four control groups: a) patients admitted with community-acquired pneumonia (n=18), b) patients with community-acquired urinary tract infection (n=42), c) patients with angiographically normal coronary artery disease (n=44), and d) patients with stable coronary artery disease (n=48). Serum immunoglobin G antibody titers to C. pneumoniae were determined using standard micro-immunofluorescene technology.

Results: Of 57 patients with AMI, 32 (56%) had a high lgG titer to C. pneumoniae (>=1:256) on the initial test, which remained unchanged (62%) after 6 weeks. The percentage of patients with high titers was significantly lower in the control groups: 5 of 18 patients (28%) in the pneumonia group (P<0.01), 11 of 42 (26%) in the urinary tract infection group (P<0.01), 11 of 44 (25%) with normal coronary arteries (P<0.01), and 17 of 48 (35%) with stable chronic ischemic heart disease (P<0.05).

Conclusion: The detection of high titers of lgG antibodies to C. pneumoniae in many patients with AMI, compared to control groups, suggest that chronic Chlamydia pneumoniae infection plays a role in the pathogenesis of atherosclerosis and acute ischemic events.