This guidelines provides information for the use of anti-virals in children who have received a human stem cell transplant.
This guideline has been developed to be used for children with haemato-oncology conditions.
Viral infection in the immunocompromised patient can be life threatening despite the use of prophylaxis. Patients thought to be infected should be assessed rapidly and treatment initiated promptly. It must be remembered that immunocompromised patients can present atypically without pyrexia and without any localising features indicating the source of the infection. The possibility of infection with opportunistic organisms such as PCP and reactivation of previous infections e.g. CMV, VZV should always be considered. Viruses such as those responsible for the common cold can cause pneumonitis and death in recipients of allogeneic stem cell transplants. Small children may be particularly vulnerable to viral infection because of lack of previous exposure. Adenovirus is amongst the commonest causes of Haemopoietic Stem Cell Transplant (HSCT) procedure related mortality in children.
Viruses can cause many different symptoms and should always form part of a differential diagnosis for any immunocompromised patient. The viruses listed below are examples of the commonest identified in HSCT patients. For other viral infections see related documentation.
CLINICAL | VIRUS |
URTI | CRV, Adenovirus |
LRTI (pneumonia) | CRV, CMV, Adenovirus |
Sinusitis | CRV |
Mucositis | HSV |
Oesophagitis/Gastritis/Colitis | HSV, CMV, Adenovirus |
Diarrhoea | Rotavirus, Adenovirus, Norovirus, Sapovirus, Astrovirus, CMV |
Haemorrhagic Cystitis | Polyomavirus, Adenovirus |
Hepatitis | HAV, HBV, HCV, CMV, EBV, Adeno (HSV, VZV, HHV6, Enteroviruses) |
PUO | CMV, EBV, Adenovirus, HHV6 |
Meningitis | HSV, VZV, Enteroviruses |
Encephalitis | HSV, CMV, EBV, HHV6, VZV |
2.1 Pre HSCT Recipient Checklist & Results for Allogeneic Patients (FORM-0003)
2.2 Virological Screening in HSCT Patients (CLIN-0008)
2.3 Diagnosis & Management of Adenovirus (CLIN-0027)
2.4 Diagnosis & Management of EBV (CLIN-0026)
2.5 Diagnosis & Management of CMV (CLIN-0014)
2.6 Administration of Cidofovir by Nursing Staff (NURSE-0004)
2.7 Pulmonary Complications Pre & Post HSCT (CLIN-0016)
2.8 Chicken Pox & Measles in the HSCT Setting (CLIN-0018)
2.9 Prevention & Control of Infection Manual
2.10 Current BNF for Children / BNF
3.1 The diagnosis and management of viral disease will be directed by the HSCT Clinical Team.
3.2 The Medical/nursing team will be responsible for the monitoring & investigation of viruses. Microbiology/Virology staff will inform of recent virology results as they become positive.
4.1 IV/Oral Inpatient Drug Administration Chart
4.2 IV Fluid Prescription Chart
5.1 VIRAL RESPIRATORY TRACT INFECTION:
For further information including clinical features see Pulmonary Complications Pre & Post HSCT SOP (CLIN-0016)
At Risk Group
Patients with respiratory symptoms or signs within any of the listed risk groups should be discussed with the HSCT Clinical Team. The decision to start treatment will be based on the patient’s clinical condition, previous treatment etc:
This list is not exhaustive and other patients can develop pneumonitis although this is less common. It should be remembered that the presence of a virus may not be the cause of the patient’s symptoms.
5.1.1 Respiratory Syncytial Virus (RSV)
RSV has a 15-20% mortality from pneumonitis in the allograft population. Patients who are RSV positive pre-allogeneic transplant should not begin conditioning until symptoms have settled and viral shedding ceased.
Surveillance
Pre HSCT assessment, which includes nasopharyngeal aspirate (NPA) and throat swab for respiratory viruses.
Investigation
Infection Control
Refer to Respiratory Syncytial Virus (RSV) NHSGG&C Control of Infection Committee Policy www.nhsggc.org.uk/infectioncontrol
Contact
If an allograft patient is in the same room as a known case, the patient must be screened.
Treatment
Ribavirin (Unlicensed medicine)
IV Dosing is not recommended for treatment of infants with RSV - SIGN guidelines 2006
Dose | Duration |
33mg/kg | Loading dose, then |
16mg/kg | 6hrly for 4 days, then |
8mg/kg | 8hrly for 3 days, then review |
5.1.2 Parainfluenza 3
Parainfluenza 3 has a mortality from pneumonitis of about 5-10% in the allograft
Patients who are positive pre-allogeneic transplant should not begin conditioning until symptoms have settled and viral shedding ceased.
LRTI should be discussed with HSCT Clinical Team. IV Ribavirin is a treatment option which may be used (see above dosing table) for a maximum of 10 days, however there is little evidence to support its efficacy.
5.1.3 Influenza A + B including H1N1
Flu A has a higher mortality than flu B from pneumonitis.
Prophylaxis
Investigation
Infection Control
Contact
If a patient on the HSCT Unit or a patient attending as an outpatient is Flu A/B positive consider giving HSCT patients who have been in prolonged contact prophylactic treatment. Current recommendations are that severely immunocompromised patients should receive Zanamivir as first line therapy, with Oseltamivir as second line therapy where Zanamivir is not a suitable option (see below for details).
Treatment for Influenza A and B and H1N1
Influenza A and B
NB: This MUST be initiated by the HSCT Clinical Team.
Severely immunocompromised patients should receive inhaled Zanamivir as first line therapy.
Zanamivir Dosing:
Inhalation of powder
Indications | Age | Dose |
Prevention during an epidemic of Influenza (prophylaxis) | 5-18 years | 10mg once daily for up to 28 days |
Treatment of Influenza | 5-18 years | 10mg twice daily for 5 days |
Post Exposure prophylaxis of Influenza | 5-18 years | 10mg once daily for 10 days |
Zanamivir is not licensed for children under 5 years old. For these children, and for any child unable to use the diskhaler, prescribe Oseltamivir. However, severely immunocompromised patients are at increased risk of developing oseltamivir-resistant influenza, therefore need close monitoring.
Oseltamivir may also be appropriate for any HSCT patients no longer considered to be severely immunocompromised.
Oseltamivir (Tamiflu) Dosing: (give once daily for 10 days for prophylaxis and twice daily for 5 days for treatment):
Age/weight | Dose | |
<1 month | 2mg/kg | |
1-3 months | 2.5mg/kg | |
3mo - 1 year | 3mg/kg | |
1-13 years | <15kg | 30mg |
15-23kg | 45mg | |
23-40kg | 60mg | |
>40kg | 75mg | |
>13 years | 75mg |
*Follow up testing may also be indicated in outbreak situations. During an epidemic prophylaxis may be used up to 6 weeks.
NB: For severely immunocompromised patients who are unable to receive Zanamivir via diskhaler and/or in cases of suspected or confirmed oseltamivir resistance, an aqueous solution of Zanamivir is available for nebulisation or IV administration. This is an unlicensed preparation which is only available on a named patient basis direct from GSK. Contact details are available in HPS Guidance document (2013)
5.1.4 H1N1
Severely immunocompromised patients should receive inhaled Zanamivir as first line therapy (see 5.1.3).
If the patient is not considered severely immunocompromised treat initially with Oseltamivir (see 5.1.3). If no response to treatment with Oseltamivir consider the possibility of drug resistance. Zamanivir is an alternative viral neuraminidase inhibitor, which may be used following discussion with the virologist.
Post exposure PROPHYLAXIS: as per dosing guidelines in 5.1.3 at using prophylactic regimen.
5.1.5 Human Metapneumovirus
This is a recognised cause of idiopathic pneumonia in immunocompromised children, putting them at risk of severe disease and hospitalisation. Patients develop rapidly spreading infiltrates and hypoxia. There are no large published studies to guide treatment. IVIgG has been used and Ribavirin demonstrates some in vitro activity.
5.2 OTHER VIRAL INFECTION
5.2.1 HHV6
HHV6 is a ß herpes virus with similarities to CMV and HHV7. It is widespread in the human population, and persists in the lymphocytes and salivary glands. It can be reactivated during times of immunosuppression.
Clinical Features
Investigation
Treatment
NB: This MUST be initiated by the HSCT Clinical Team
Duration: Until patient improves
5.2.2 HSV
Clinical Features
Prophylaxis
Aciclovir Dosing:
Age | Dose |
1month-2yrs |
100-200mg four times daily orally |
2yrs-18yrs |
200-400mg four times daily orally IV: 250mg/m2 three times daily (<12yrs) |
At Risk Group
Surveillance
Pre HSCT assessment, which includes serological testing
Investigation
Treatment
1st line: ACICLOVIR IV
Age | Dose |
Child 1 - 3 months |
20mg/kg three times daily for 14 days (21 days if CNS involvement) |
3months-12years |
500mg/m2 three times daily for 5 days (21 days if CNS involvement) |
12years-18years |
10mg/kg three times daily for 5 days (21 days if CNS involvement) |
NB: Commence IV maintenance fluids during IV aciclovir administration. In renal impairment see dose adjustment table (Section 5.3).
If aciclovir resistance is suspected, a swab in viral transport medium should be sent to virology.
2nd line GANCICLOVIR see dosing and administration in Diagnosis & Management of CMV SOP (CLIN-0014)
3rd line: FOSCARNET IV infusion 40mg/kg three times a day for 2 - 3 weeks or until lesions heal (see dosing & administration).
5.2.3 VSV
NB: VZV titres should be assessed for of all at risk patients prior to commencement of immunosuppressive treatment. See Chickenpox & Measles in the HSCT Setting SOP (CLIN-0018)
5.2.4 COVID
All patients and household contacts should be vaccinated if eligible .The field of antiviral / antibody therapies is changing fast and all patients should be discussed with Infectious Diseases to assess eligibility for treatment.
5.3 DRUG DOSE REDUCTION IN RENAL IMPAIRMENT
DRUG | DOSE SCHEDULE |
Aciclovir | IV - Dose adjustments required for GFR 50ml/min or less. Refer to Renal Drug Database. Oral - Dose adjustments required for GFR 25ml/min or less. Refer to Renal Drug Database. |
Foscarnet | See Diagnosis and Management of CMV SOP |
Oseltamivir | Dose adjustments required for GFR 60ml/min or less. Refer to Renal Drug Database. |
Ganciclovir | See Diagnosis and Management of CMV SOP |
This SOP will be reviewed every two years.
Identify how the procedure/process within the SOP will be audited
For further information contact:
Haemopoietic Stem Cell Transplant Team On-Call Consultant (via switchboard)
Last reviewed: 01 April 2022
Next review: 30 April 2024
Author(s): Dr A M Ewins
Version: 3
Approved By: Schiehallion Clinical Governance Group
Document Id: RHC-HAEM-ONC-021