Tularemia - lab diagnosis?"The diagnosis of tularemia ultimately rests on clinical suspicion. Results of routine laboratory testing are nonspecific. The leukocyte count and sedimentation rate may be normal or elevated. Thrombocytopenia, hyponatremia, elevated serum transaminases, increased creatine phosphokinase, myoglobinuria, and sterile pyuria are occasionally found. 1 The organism is rarely seen on Gram-stained smears or in tissue biopsies and does not grow in routinely plated cultures. However, F. tularensis may be recovered from blood, pleural fluid, lymph nodes, wounds, sputum, and gastric aspirates when processed on supportive media. Because of this and its potential danger to laboratory personnel, individuals working in the area or who may come in contact with the specimens should be notified if tularemia is suspected. Isolations by blood culture have included the less virulent holarctica (type B) strains as well as the more virulent tularensis (type A) strains. Animal inoculation is rarely performed, in part because this requires Biosafety Level 3 facilities. Biosafety Level 2 is sufficient for laboratory handling of routine clinical specimens, but Biosafety Level 3 should be used to process isolates suspected of being F. tularensis."
From Chapter 227 Francisella tularensis (Tularemia) from Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases (Mandell, 7th ed)