Apparent meningococcemia: clinical features of disease due to Haemophilus influenzae and Neisseria meningitidis.

To determine the etiology of apparent meningococcemia, all cases of sepsis with coagulopathy, purpura, and/or adrenal hemorrhage (Waterhouse-Friderichsen syndrome) with and without shock occurring over a 12-year period were reviewed. A total of 42 cases were identified; 30 cases were caused by Neisseria meningitidis and 12 cases were caused by Haemophilus influenzae. Compared with patients with disease caused by H influenzae, patients with meningococcal disease were older, more often male, more often contracted the disease in winter-spring, and had a longer duration of antecedent symptoms; however, none of these differences was statistically significant. All patients were febrile (greater than 38 degrees C) and appeared toxic. Similar proportions in each group had shock and disseminated intravascular coagulopathy at the time of admission. Ten of 12 patients with H influenzae infection compared with 15/30 (P less than .05) with meningococcal infection were lethargic or comatose at the time of admission. Nine of 12 patients with H influenzae infection died compared with 5/30 with meningococcal disease (P less than .005); the mean time from onset of symptoms to death with H influenzae infection (20.7 +/- 11.4 [SE] hours) was significantly shorter (P less than .05) than with meningococcal infection (120 +/- 74.4 hours). Children with clinical signs of sepsis and with purpura, petechiae, or coagulopathy may have N meningitidis or H influenzae as etiologic agents. Initial antibiotic therapy should be directed against these pathogens.