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AimDevelop the hydroxycarbamide prescribing process for sickle cell disease to improve outcomes and patient experience through: implementing electronic prescribing; identifying and addressing non-adherence; optimising doses; improving accessibility of medication and developing a hydroxycarbamide telephone clinic.MethodThe clinic was planned to be piloted mid-2020 however due to the COVID pandemic requiring more services to be delivered remotely the timeline was accelerated and all patients switched to telephone reviews in March 2020.New patients are commenced on hydroxycarbamide at a face-to-face outpatient appointment which includes counselling and consent, review of baseline bloods, introduction to the telephone clinic and medication counselling.Patients are then eligible for the hydroxycarbamide telephone clinic. Patients attend outpatient phlebotomy for the necessary monitoring blood tests prior to their telephone appointment. At the telephone appointment a virtual review takes place including a review of symptoms, blood results, medication adherence and adverse effects. An 8-12 week supply of hydroxycarbamide is prescribed by a nurse or pharmacist prescriber and sent to the patient’s local pharmacy or home address by the hospital outsourced pharmacy. Follow up appointments are made every 8-12 weeks.Patients continue to have face to face medical appointments; the interval is determined by individual patient factors but a minimum of annually.ResultsIn September 2019 (prior to electronic prescribing) an audit of patients who had been on hydroxycarbamide for 9 months or more (n=26) had a mean dose of 21.7mg/kg. A repeat audit in July 2021 showed a mean dose of 26.9mg/kg (n=36).Electronic prescribing has facilitated more accurate prescription records and structured dose escalation. It also supports better monitoring of adherence since it is clear during a review when the next supply should be required. This along with questioning what medication supply patients have at home allows adherence issues to be identified and discussed with patients/carers.An audit of haematology outpatient clinic waiting times prior to implementation showed an average wait time of 82 minutes; one of the recommendations was to implement this telephone clinic. In a patient/carer survey on care during the pandemic, 88% of respondents were happy with the telephone reviews they had received and 82% wished to continue with telephone clinics.ConclusionThe results show an escalation in hydroxycarbamide dose which correlates with a higher fetal haemoglobin, this in turn is associated with increased survival.1. This has been facilitated by the increased opportunity to focus on prescribing and medication review. From March 2020 to May 2021, due to the pandemic, dose escalation only took place if patients were admitted with crisis so further improvement may be seen in the future.Full patient/carer involvement wasn’t possible in the initial set up of this new service due to pandemic limitations and the rapid implementation this necessitated. This may have contributed towards challenges with attendance for blood tests. Although the results show positive attitudes towards the clinic, re-audit of outpatient waiting times and patient/carer satisfaction is planned as the service is developed further.ReferenceQureshi A, Kaya B, Pancham S, et al. Guidelines for the use of hydroxycarbamide in children and adults with sickle cell disease: a british society for haematology guideline. British Journal of Haematology 2018;181:460-475.

SituationA 30 week gestation male weighing 1.66kg presented with metabolic acidosis and high lactate and subsequently developed heart failure and hypertension. He initially started enteral feeds but these were later not tolerated and TPN commenced. On day 8 calcification of the aorta was identified on echocardiogram. CT scans showed extensive arterial calcification including the thoracic and abdominal aorta, subclavian and common carotid arteries, coeliac axis, SMA, renal arteries and iliac vessels. Generalised arterial calcification of infancy (GACI) due to ENPP1 mutation was suspected.BackgroundGACI, a rare autosomal recessive condition can be caused by ENPP1 mutation leading to low levels of inorganic pyrophosphate (PPi), a negative regulator of calcification. GACI has a high mortality rate, up to 55% at 6 months. Mortality has been shown to improve in those who survive the first few months of life.1TreatmentIntravenous sodium thiosulfate, licensed for cyanide poisoning and used off-label for calciphylaxis in adults,2 was commenced to try and reduce existing calcification. Dosing that has been known to be used in three other babies from two different centres,3 was used - 12.5g/m2 over 30minutes on alternate days for 2 weeks followed by 12.5g/m2 five days a week. This is in the same scale as adult calciphylaxis dosing and up to 400mg/kg can be used in paediatric cyanide poisoning. Bisphosphonates were commenced to prevent further calcification. Etidronate, a non-nitrogen containing bisphosphonate, was preferred due to its closer structural similarity to PPi than second generation bisphosphonates. Etidronate has been discontinued in the UK so was not initially available and a dose of pamidronate was given. A Canadian import of etidronate was sourced and commenced a week later. Due to SMA and coeliac axis calcification there were concerns regarding bowel perfusion and he was TPN fed except for 20ml/kg/day EBM. Etidronate 20mg/kg/day was commenced in three divided doses to improve gastrointestinal tolerance.OutcomeInitially his heart failure stabilised and hypertension managed with carvedilol. By day 35 full enteral feeds were reached and he was breathing unassisted in air. CT after one month’s treatment showed no worsening of vascular calcification, though unfortunately calcification did not appear to have improved. At 7 weeks he became tachypnoeic due to worsening heart failure and required respiratory support. Despite ongoing medical therapies he passed away at 8 weeks of age.Challenges and lessons learntDue to the rarity of the condition information on treatment options, dosing and monitoring are limited and the need to use an imported product lead to a short delay in treatment. Etidronate is only available in tablet form but Didronel brand can be crushed and suspended in water,4 Information about the suspension’s uniformity is unavailable but due to a lack of alternatives this was the option taken. A two hour break either side of etidronate while recommended, was compromised to ninety minutes as he required three hourly feeds. Combination treatment was used to try to reduce the calcification; however the extent of calcification had already caused significant cardiac compromise which ultimately led to his demise.ReferencesFerreira C, Ziegler S, Gahl WA. Generalized Arterial Calcification of Infancy. 2014 In: Adam MP, Ardinger HH, Pagon RA, et al., editors. GeneReviews [Online]. Seattle (WA): University of Washington, Seattle; 1993–2018. Available from: https://www.ncbi.nlm.nih.gov/books/NBK253403Nigwekar SU, Brunelli SM, Meade D, et al. Sodium thiosulfate therapy for calcific uremic arteriolopathy. Clin J Am Soc Nephrol, 2013;8:1162–70.Personal communication: Medicines Information, Alder Hey Children’s NHS Foundation Trust. Email sent to: Leeds Medicines Advisory Service. 28th June 2018.White R, Bradnam V. Handbook of Drug Administration via Enteral Feeding Tubes, Third ed. Cornwall: Pharmaceutical Press; 2015. www.medicinescomplete.com (accessed August 2018).