Approach to treating cytomegalovirus disease
Treatment of cytomegalovirus (CMV) disease is complex—seek expert advice.
As CMV disease usually occurs in patients with immune compromise, consider investigating for an immune system disorder, especially in patients without known immunosuppression. In particular, CMV retinitis is an indicator condition for HIV testing1. If CMV retinitis is identified, offer HIV testing to all patients, regardless of whether the patient has behavioural or epidemiological risk factors for HIV infection.
In neonates with congenital CMV disease, ganciclovir (or valganciclovir) may reduce hearing impairment and improve neurodevelopmental outcomes when started within the first 4 weeks of life. Valganciclovir is often preferred because it can be given orally and has fewer adverse effects. Seek expert advice and see the Australasian Society for Infectious Diseases (ASID) guideline Management of Perinatal Infections [URL] for information on management.
In transplant recipients, either a prophylactic strategy or selective pre-emptive treatment may be used to reduce the risk of CMV disease; for details, see Cytomegalovirus prophylaxis in immunocompromised adults without HIV infection. Treatment of CMV syndrome and active disease in transplant recipients is addressed in this topic.
Management of CMV disease in immunocompromised patients includes reducing the level of immunosuppression if possible (seek expert advice), and treatment with antiviral therapy. Systemic antiviral therapy is always recommended. Oral valganciclovir has been shown to be equally effective to intravenous ganciclovir in some settings, but has not been studied in all situations. In cases of severe CMV retinitis, local antiviral therapy may be used in addition to systemic therapy. (In patients with CMV disease who need to be started on antiretroviral therapy for HIV, see Cytomegalovirus (CMV) disease in adults with HIV infection).
Antiviral therapy is considered in two phases—treatment of active disease, followed by secondary prophylaxis in some patients (see #abg16-c21-s3__tabg16-c21-tbl2). The evidence for secondary prophylaxis in most settings is weak.
The duration of therapy is determined by response to treatment, which is defined clinically and with suppression of CMV viraemia. Active disease is treated for a minimum of 2 weeks, although longer durations are often needed in patients with colitis or high initial viral loads. Treatment should be monitored with at least weekly measurement of CMV viral load to ensure response. If CMV viraemia persists, treatment may need to be extended because there is a risk of relapse.
See #abg16-c21-s3__tabg16-c21-tbl2 for a summary of recommendations for antiviral therapy of CMV disease, including drug selection, duration of treatment and role of secondary prophylaxis. Drug dosage regimens are provided in Antiviral therapy for cytomegalovirus disease in adults and Antiviral therapy for cytomegalovirus disease in children. For information on dosage adjustment in adults with kidney impairment, see here; for children, seek expert advice. Monitor blood count and kidney function closely. For information on monitoring blood concentrations of ganciclovir and valganciclovir, see Monitoring guanine analogue antivirals.