Coagulation Studies in Argentine Hemorrhagic Fever

33 patients with Argentine hemorrhagic fever (AHF) grouped into mild (18 cases), moderate (9 cases) and severe (5 cases) clinical forms were studied from day 6th to day 22nd after the onset of Symptoms. The evolution profile of the coagulation factors wns similftr in all AHF patients regardless of the clinical form. PTTK was prolonged in the early stages ( 78.0 ± 5.8 see on day 6th and 47.5 ± 1.9 sec on day 14th). However, the values of F VIII, F IX and F XI ranged in the lower normal limits. Quick time, factors II and VII-X remained within the normal range. In contrast F V activity was greatly enhanced ( 257.5 ± 54.7% on day 10th). Congulation alterations tended to normalize after 14 days of evolution. Fibrinogen profiles differed in the three clinical forma. In the moderate and severe AHF groups fibrinogen increased to a mean of 532 ± 30.3 and 472 ± 40.9 mg% on day 12th of evolution. No fibrin monomers nor fibrinogen degradation products were detected. The clotting system abnormalities were observed cnincidentally to the described alterations of the complement system. The present results indicate that if activation took place there was no evidence of thrombin formation.