Viral Infections in Patients with Hematological Malignancies

Abstract

Viral infections are important causes of morbidity and mortality for patients with a hematological malignancy. However, the true incidence and consequences of viral infections for these patients who undergo conventional nontransplant therapy are poorly defined. The difference in incidence and outcome of viral infections among patient groups is wide, but dependent upon the intensity and duration of T-cellmediated immune suppression. Infections caused by cytomegalovirus (CMV), herpes simplex virus (HSV), varicella-zoster virus (VZV), respiratory syncytial virus (RSV), parainfluenza viruses and influenza viruses have been intensely studied, yet newly recognized aspects of these viral infections including late CMV infection; the emergence of new viral pathogens (human herpesvirus-6, BK virus, adenovirus, and human metapneumovirus); the development of molecular diagnostic techniques, and the potential of new agents for viral prophylaxis (maribavir), or preemptive therapy (valganciclovir) form the basis of this review. Well-designed prospective studies are needed to better clarify the spectrum of these viral infections and develop effective prevention and treatment strategies. Yet the increased use of agents like alemtuzumab that induce profound T-cell depletion demands that we develop a better understanding of viral infections that occur in patients with hematological malignancy who receive nontransplant therapy.

Risk of Infections in Adult Patients with Haematological Malignancies

“…T-cell function is paramount in the control of CMV, and T-cell depleting agents (e.g., alemtuzumab) and aggressive chemotherapy appear to increase the risk of CMV infection and disease [48]. The incidence of CMV infection and disease is less clearly defined for patients with haematological malignancies who receive conventional therapy.…”

“…Respiratory syncytial virus, Influenza A and B viruses, and parainfluenza viruses are all widely described as causes of severe respiratory infections in patients with haematological malignancies [48]. But also human enterovirus and human rhinovirus respiratory tract infections are in a Spanish study described as being relatively common in haematological patients [49].…”

“…In a study including 100 immunocompromised patients hospitalised with upper respiratory tract infection due to Influenza a haematological malignancy diagnosis predicted a high risk of progression to pneumonia [50]. Although, the utility of influenza vaccination in patients with haematological malignancy remains controversial [48] recent conclusions have been that patients with cancer receiving chemotherapy are able to respond to influenza vaccination, and because this intervention is safe, inexpensive, and widely available, vaccination for seasonal influenza and the novel H1N1 strain is indicated [51]. According to the IDSA guidelines yearly influenza vaccination with inactivated vaccine is recommended for all patients being treated for cancer [20].…”

IE63-specific T-cell responses associate with control of subclinical varicella zoster virus reactivation in individuals with malignancies

“…Immediate-early protein 63 (IE63)-specific T-cell responses were significantly impaired in those with subclinical VZV re-activation. Malignancy is associated with reactivation of chronic persistent viruses such as varicella zoster virus (VZV) (Whiteside, 2006), causing significant morbidity and mortality (Wade, 2006). Herpes zoster is more common in patients with malignancies (Schmader, 2001;Sorensen et al, 2004) and may lead to severe disease with multi-dermatomal involvement and visceral dissemination, which can be lethal (Gallagher and Merigan, 1979;Onunu and Uhunmwangho, 2004;Hackanson et al, 2005;Graue et al, 2006).…”

Herpetic infection in a patient with pyoderma gangrenosum and chronic myeloid leukaemia

“…Mucocutaneous HSV disease in patient with hematological malignancies often mimics other pathogens, such as Candida, or treatment-induced mucositis. In case of CML, a herpetic infection can be responsible for mucocutaneous blisters which developed into chronic ulcers mimicking a dermatological blistering disease (3). The association between PG and herpetic infection could be explained by the use of high-dose immunosuppressive treatment for PG, that predisposes patients to opportunistic infections.…”