[Diagnosis of lymphocytopenia].
Lymphopenia is defined as a peripheral lymphocyte count lower than 1500/mm3 in adults and 4500/mm3 in children younger than eight months of age. We propose a classification of lymphopenia according to the mechanism involved: lymphocyte production defects, including primary immune deficiencies and immune deficiencies secondary to malnutrition or zinc deprivation; excess catabolism, due to causes including radiotherapy, chemotherapy, immunosuppressive therapy, HIV infection, and systemic lupus erythematosus; abnormal lymphocyte trapping, including mainly splenomegaly, certain viral infections, septic shock, extended burns, systemic granulomatosis, and corticosteroids; other causes of lymphocytopenia, with mechanisms that remain poorly understood: ethnicity (Ethiopians), lymphoma, renal insufficiency, and idiopathic CD4 lymphocytopenia.
Berezné
Alice
A
Service de médecine interne, Hôpital Cochin, AP-HP, université Paris-Descartes, faculté de médecine, Paris (75).
Bono
Wafaa
W
Guillevin
Loïc
L
Mouthon
Luc
L
D006801:Humans; D008231:Lymphopenia / Q000145:classification / Q000175:diagnosis* / Q000209:etiology