Beyond Pneumonia: A Rare Case of Pericardial Empyema Caused by Streptococcus pneumoniae.

Purulent pericardial effusion is a rare but potentially deadly condition that demands immediate medical attention. When left untreated, it can have catastrophic consequences. While bacterial infection is the most common cause of this condition, it usually occurs in individuals with weakened immune systems or in those undergoing dialysis or thoracic surgery. This case report presented here is unique as it chronicles the uncommon experience of a 58-year-old male with a normally functioning immune system who suffered from purulent pericardial effusion, endocarditis, and pneumonia, all linked to septic arthritis of his knee caused by Streptococcus pneumoniae. The diagnosis and management of this condition require a swift and comprehensive approach, and any delay in treatment can have dire outcomes. This case highlights the significance of early detection and prompt treatment of purulent pericardial effusion to prevent severe complications and improve patient prognosis.

Differences in prethrombin-1 activation with human or bovine factor Va can be attributed to the heavy chain.

Human and bovine factor Va (FVa) function similarly in the activation of prothrombin but differently in the activation of prethrombin-1 (Pre-1). Pre-1 activation with human FVa proceeds at about 22 percent of the rate with bovine FVa. The dependencies of initial rates on the FVa and Pre-1 concentrations indicate that the differential activity is expressed in kcat differences, rather than differences in the assembly of prothrombinase or the K(m) value of the substrate. The heavy and light chains of both species of FVa were separated and interspecies hybrids were constructed in the presence of Ca(++). Studies of the activation of Pre-1 with these hybrids indicate that the species difference can be attributed specifically to the heavy chain of FVa. Analyses of the reactions by SDS-PAGE indicated that cleavage at Arg271 occurs at about the same rate with both species of FVa, but cleavage at Arg320 with human FVa is specifically retarded. A major difference in primary structure between the human and bovine FVa heavy chains comprises 10 residues at COOH-terminus, adjacent to the negatively charged hirudin-like DYDYQ sequence. These residues have pI values of 12.5 and 4.26 in human and bovine FVa, respectively. The lower value would complement the negatively charged DYDYQ sequence but the higher value would counteract it. Thus, we suggest that the differences in the COOH-terminus of the heavy chain are responsible for the differences in Pre-1 activation, and that it specifically influences cleavage at Arg320 in Pre-1.