Only two patients were positive for IgM antibodies (also they had IgG antibodies): one for R. conorii antibodies (that of a 59 year-old man with abdominal pain, lymphopenia, hyperbilirubinemia, and elevated phosphatase alkaline [FA], lactate dehydrogenase [LDH] and gamma-glutamyl transferase [GGT]); the other for R. typhi antibodies (that of a 27 year-old man with elevated GGT). The gene discussed is CD40LG; the disease is lymphopenia.