Acute serogroup A streptococcal shock: A porcine model.
To elucidate the pathophysiology of acute shock caused by serogroup A streptococci (GAS), GAS were given intravenously to 25 pigs. Short-time infusions of GAS (n=11) caused variable and unpredictable responses. A continuous infusion of 5x108 cfu/kg/h (n=8) caused pulmonary hypertension, arterial hypotension, and reduced cardiac output and liver perfusion, progressing to circulatory shock within 2-4 h. Halving the infusion rate (n=6) induced a more gradual development of shock and doubled the mean survival time from 2.1 to 4.0 h. Mean tumor necrosis factor-alpha levels (+/-SE) increased from 25+/-1 to 40+/-3 pg/mL. Only slight signs of organ dysfunction were observed, which indicates that this is primarily a model of acute septic shock. Light microscopy revealed moderate inflammatory reactions in lung, liver, and gut biopsy samples, although high numbers of viable, M-typeable GAS were recovered from tissues. The present model may be useful to study mechanisms involved in acute septic shock as well as therapeutic interventions.
Saetre
T
T
Department of Surgery, Ullevaal University Hospital, 0407 Oslo, Norway. torunn.satre@ioks.uio.no
Hoiby
E A
EA
Aspelin
T
T
Lermark
G
G
Lyberg
T
T
D000818:Animals; D001769:Blood / Q000382:microbiology; D001784:Blood Gas Analysis; D004195:Disease Models, Animal; D004618:Embolism, Air / Q000209:etiology; D005260:Female; D006976:Hypertension, Pulmonary / Q000209:etiology; D007022:Hypotension / Q000209:etiology; D008297:Male; D009102:Multiple Organ Failure / Q000209:etiology; D012769:Shock / Q000209:etiology; D012772:Shock, Septic / Q000378:metabolism / Q000503:physiopathology*; D013290:Streptococcal Infections / Q000378:metabolism / Q000503:physiopathology*; D013297:Streptococcus pyogenes / Q000254:growth & development / Q000472:pathogenicity*; D013552:Swine; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism
D014409:Tumor Necrosis Factor-alpha