Streptococcus pyogenes Pericarditis with Resultant Pulmonary Trunk Compression Secondary to Mycotic Pseudoaneurysm.

Purulent pericarditis is a rare disease in the era of antibiotics, with Streptococcus pyogenes being a possible, though uncommon etiology. Even more uncommon are mycotic aneurysms secondary to group A strep purulent pericarditis and bacteremia. We report a case of an 18-year-old female with a history of strep pharyngitis develop Streptococcus pyogenes purulent pericarditis with subsequent ventricular fibrillation (VF). Following initial stabilization, she ultimately developed a 4.8 cm mycotic aneurysm of the ascending aorta, with resultant compression of the pulmonary trunk and right pulmonary arteries.

Capnocytophaga species: increased resistance of clinical isolates to serum bactericidal action.

Capnocytophaga, a newly recognized genus of capnophilic gram-negative bacilli, is part of the normal oral flora. The capacity of Capnocytophaga to cause sepsis and local infections in both immunocompromised and nonimmunocompromised hosts has been documented. Given the recognition that serum resistance may contribute to the virulence of some gram-negative bacteria, we attempted to define the serum sensitivity of clinical isolates of Capnocytophaga from blood and other sites of infection. Whereas nine of nine isolates from human subgingival plaque showed greater than 95% loss of viability under standardized assay conditions, nonoral isolates exhibited variable serum sensitivity. Six of six isolates from blood showed considerable serum resistance (mean survival, 59.7% +/- 38.3%; range, 14.4%-113.3%). Comparison of the electrophoretic mobilities of lipopolysaccharides (LPSs) from sensitive and resistant strains revealed reduced LPS heterogeneity and lower apparent molecular weight among serum-resistant strains. Thus, serum resistance, possibly influenced by LPS structure, may be an important factor contributing to the pathogenic potential of Capnocytophaga spp.

The peptide beta 43-47 which increases microvascular permeability is released by plasmin during cleavage of fragment Y of fibrinogen.

A synthetic pentapeptide corresponding to sequence 43-47 of human fibrinogen B beta chain elicited, in rabbits, antibodies that during immunoblotting recognized intact fibrinogen, fragments X and Y as well as the B beta chain. Since fragment Y is the last peptide product which reacts with anti-beta 43-47 antibodies, splitting of fragment Y into fragment D and fragment E must be accompanied by plasmin cleavage of the peptide bond beta Lys-47-Ala-48.

Sensitivity of Capnocytophaga species to bactericidal properties of human serum.

Capnocytophaga is a newly described genus of gram-negative bacteria which can cause serious oral and extraoral infections in the susceptible host. In the present study, sensitivity of Capnocytophaga spp. to the bactericidal properties of human serum was investigated. Laboratory strains representative of Capnocytophaga sputigena, C. ochracea, and C. gingivalis and seven oral isolates of Capnocytophaga spp. obtained in primary culture were determined to be sensitive to killing by pooled normal serum. In contrast, little or no killing of Capnocytophaga spp. was observed when these organisms were incubated in the presence of hypogammaglobulinemic serum despite evidence for alternative pathway activation. However, hypogammaglobulinemic serum could be reconstituted to bactericidal activity by the addition of the immunoglobulin M fraction of normal serum. Capnocytophaga spp. failed to activate the classical pathway in hypogammaglobulinemic serum, thus ruling out an antibody-independent mechanism of killing. In contrast, good correlation was observed between serum-mediated killing and antibody-dependent classical pathway consumption. These results indicate that complement in the presence of bactericidal antibody may be an important determinant of host resistance to intra- and extraoral infections caused by Capnocytophaga spp.

Value of re-interviewing in contact tracing.

PIP: The epidemiological importance of reinterviewing in contact tracing, using those treated for venereal is demonstrated. Interviewing as a preliminary to contact tracing is usually done by the physician in charge. When 160 patients with early syphilis failed to provide information on contacts, they were reinterviewed by a skilled interviewer trained in psychology and working in pleasant surroundings. The reinterviews brought 208 named contacts, 189 of whom were contacted and 88 of whom has syphilis. Women proved more cooperative in listing contacts; unmarried people were more cooperative than married. Reasons for patients giving inadequate information were often the casual nature of the sexual contact and, in the case of the young girls, the multiplicity of partners. This indicated the marked trend toward sexual promiscuity, especially among the young.^ieng