Finger-prick autologous blood relieves refractory dry eye
Shafi Balal MD
A droplet of blood from a pricked finger applied directly to the eye can relieve the symptoms of dry eye disease and persistent epithelial defects unresponsive to conventional therapy, according to the findings of a pilot study presented by Shafi Balal MD at the XXXIV Congress of the ESCRS in Copenhagen, Denmark.
The senior author and supervising consultant for the study is Mr Anant Sharma, of Moorfields Eye Hospital, London, UK. Dr Balal, also of Moorfields Eye Hospital, noted that the finger-prick autologous blood (FAB) treatment probably works by the same mechanisms as other blood-derived products, such as autologous serum and platelet-derived plasma, which have been shown to be effective for the same indications in clinical trials. However, those treatments have not been widely adopted owing to the expense and time involved in producing the blood products.
In contrast, FAB involves almost no expense and simply requires patients to trim their fingernails, wash their hands, sterilise their finger with an alcohol steret and prick it with a diabetic lancet, then apply a drop of blood directly from their fingertip to the lower fornix of each affected eye, he said.
Dr Balal reported a study involving 12 patients with dry eye syndrome and three patients with non-infective persistent epithelial defects. All underwent FAB treatment four times daily for eight weeks and then were followed for a further four weeks.
Prior to undergoing FAB treatment, the patients with dry eye all had tear break-up time (TBUT) of less than five seconds and Schirmer without local anaesthetic of less than or equal to 5mm, or punctuate fluorescein staining of ocular surface or an ocular comfort index (OCI) score of higher than 80%. In addition, all had tried cyclosporine and punctal plugs or refused the treatments. The patients with non-infective persistent epithelial defects had a duration of at least two weeks and their corneal lesions had failed to decrease in size with conventional therapy, or had not resolved after four weeks of conventional treatment.
After eight weeks FAB treatment, the patients’ mean Oxford corneal staining grade improved from 3.67 to 2.33 (p<0.0001), tear break-up time increased from 5.24 seconds to 7.71 seconds (p<0.001) and OCI score improved from 53.17 to 27 (p<0.001). There were also improvements in mean visual acuity and Schirmer’s scores but these did not reach statistical significance. There were no complications or adverse events.
Four weeks after treatment cessation, mean Oxford staining grade, OCI and TBUT scores all worsened. However, persistent epithelial defects had resolved after one month of treatment in two of three patients, Dr Balal said.
Fingertip autologous blood possesses several theoretical advantages over autologous serum
MANY PRACTICAL ADVANTAGES
Several peer-reviewed studies have shown autologous serum to be effective in a range of corneal conditions. The treatment’s current indications include limbal stem cell deficiency, recurrent erosion syndrome, diabetic keratopathy, and graft vs. host disease.
Barriers to wider adoption of autologous serum include the initial cost of €1,900 and then €450 per month. There is a delay in obtaining funding and there can be a delay in production of drops, since not all laboratories perform the necessary processes on blood products. Moreover, patients have to store the product in the refrigerator at home.
“Fingertip autologous blood possesses several theoretical advantages over autologous serum. Its costs are limited to the purchase of alcohol sterets and diabetic lancets and it requires no storage whatsoever,” Dr Balal said.
He noted that, although the treatment must be maintained over the long-term in dry eye, patients using FAB for the indication are highly motivated to continue their therapy by the relief it provides. He added that he and his associates are researching the possibility of using less painful lancets.
In addition, plans are under way for a randomised controlled trial recruiting patients from several centres across the UK and also extending their recruitment indication to patients with Meibomian gland dysfunction, Dr Balal said.
“FAB is an alternative low-cost, readily accessible treatment for dry eye syndrome, and also for persistent epithelial defects,” Dr Balal concluded.
Correspondence to Anant Sharma:
The authors also acknowledged Moorfields NIHR BRC for support