Q; Which laboratory triad is highly suspicious and virtually diagnostic of Hantavirus?


Answer: 

• Thrombocytopenia
• a left-shifted granulocytic series
• an immunoblast abundance that exceeds 10 percent of the total lymphoid series

In cases, where suspicion of Hantavirus is high due to history of exposure, above triad is virtually diagnostic. Moreover, it carries an extremely significant herald of probable life-threatening Hantavirus Cardiopulmonary Syndrome. It warrants transfer to a tertiary care center where Extracorporeal Membrane Oxygenation (ECMO) is available.


References:

1. Koster F, Foucar K, Hjelle B, et al. Rapid presumptive diagnosis of hantavirus cardiopulmonary syndrome by peripheral blood smear review. Am J Clin Pathol 2001; 116:665. 

2. Moolenaar RL, Dalton C, Lipman HB, et al. Clinical features that differentiate hantavirus pulmonary syndrome from three other acute respiratory illnesses. Clin Infect Dis 1995; 21:643.