Table 1.
Differential Diagnosis of Acutely Ill Febrile Adult Patient with Noniatrogenic Leukopenia and Thrombocytopenia∗
| Viral infections |
| Herpes viruses: EBV, CMV, HHV6, VZV, HSV |
| Measles, rubella |
| Hepatitis viruses A and B |
| HIV infection and AIDS |
| Parvovirus B19 |
| Dengue virus infection† |
| Severe acute respiratory syndrome coronavirus† |
| Influenza viruses |
| Nonspecific viral infections/postinfectious |
| Post-viral vaccines |
| Bacterial infections |
| Overwhelming sepsis, any organism (especially Gram-negative) |
| Toxic shock syndrome (staphylococcal, streptococcal) |
| Typhoid fever (Salmonella typhi and paratyphi) |
| Shigella enteritis |
| Campylobacter infections |
| Rickettsial infections† (spotted fevers, typhus) |
| Human ehrlichiosis and anaplasmosis† |
| Coxiella burnetii infections† (Q fever) |
| Bartonella infections† (cat scratch disease) |
| Brucellosis† |
| Leptospirosis† |
| Tularemia† |
| Lyme disease† (Borrelia burgdorferi) |
| Relapsing fever† (Borrelia sp.) |
| Tuberculosis (Mycobacterium tuberculosis) |
| Mycoplasma pneumoniae infection |
| Parasitic infections |
| Toxoplasmosis† |
| Malaria |
| Visceral leishmaniasis† |
| Varied conditions |
| Sarcoidosis |
| Systemic lupus erythematosus |
| Lymphoma or leukemia (eg, LGL syndrome) |
| Felty's syndrome |
| Hemophagocytic syndrome |
AIDS = acquired immunodeficiency syndrome; CMV = cytomegalovirus; EBV = Epstein-Barr virus; HHV6 = human herpesvirus 6; HIV = human immunodeficiency virus; HSV = herpes simplex virus; LGL = large granular lymphocyte; VZV = varicella zoster virus.
∗
Excluding patients with prior cytopenias due to cancer/cancer treatment, portal hypertension, autoimmune disease, or ethnic leukopenia. White blood cell count occasionally may be normal despite high fever (“relative” leukopenia).
†
Zoonosis.