Natural killer (NK) cell deficiency syndromes are rare disorders in which NK cells are absent, deficient, or dysfunctional, in the absence of any other identifiable immunodeficiency, genetic disorder, or medication known to affect NK cells. These disorders are categorized as classical NK cell deficiency (CNKD) and functional NK cell deficiency (FNKD).
The management of patients with these disorders is discussed here. The biology of NK cells, the clinical manifestations of NK cell disorders, and the evaluation of patients suspected of having NK cell defects are presented separately. (See "NK cell deficiency syndromes: Clinical manifestations and diagnosis".)
Therapy for patients with natural killer (NK) cell deficiency syndromes is largely empiric, due to the small numbers of cases described in the literature. Active infections must be identified and treated aggressively, as with any immune disorder. (See "Medical management of immunodeficiency".)
The use of specific therapies is based either on theoretical utility or anecdotal reports of benefit (table 1).
Natural killer (NK) cell disorders are characterized clinically by susceptibility to severe and/or recurrent infection with herpes viruses, including varicella zoster virus (VZV), Herpes simplex virus (HSV) I and II, Epstein Barr virus (EBV), and cytomegalovirus (CMV). There is also a marked susceptibility in some patients to Human Papilloma Viruses.