Others

Intestine

Intestinal transplantation alone, or together with other organs as a multivisceral graft, is considered the standard treatment for patients with intestinal failure (Middleton et al., 2014). Small bowel transplantation is the most effective treatment in the management of paediatric short bowel syndrome (Zavras et al., 2015).

Analysis of 852 paediatric cases who received an intestinal transplant showed that 69% also received a simultaneous liver transplant (Lao et al., 2010). The more common underlying diagnoses in this series of patients were:

  • gastroschisis (24%)
  • necrotising enterocolitis (15%)
  • volvulus (14%)
  • other causes of short-gut syndrome (19%)
  • functional bowel syndrome (16%)
  • Hirschsprung disease (7%)

The most common indications for intestinal transplant in the US during 2015 (Smith et al., 2017) were:

  • short gut syndrome (other) (51.4%)
  • congenital short gut syndrome (10.0%)
  • pseudo-obstruction (8.6%)

Cornea

The procedures for corneal transplantation or keratoplasty are: whole organ transplant, known as penetrating keratoplasty; or lamellar transplantation surgery, in which only the diseased layers of the cornea are replaced (Tan, 2012; Kymionis et al., 2014).

Indications for penetrating keratoplasty include: failed graft; the degenerative disorder, bullous keratopathy; keratoconus; corneal scar; corneal perforation from infection; and the genetic disorder, Fuchs’ endothelial dystrophy. Failed graft was the most common indication for transplantation (29%) in a retrospective analysis of one series of patients (Randleman et al., 2003).

Indications for corneal endothelial transplantation or endothelial keratoplasty include: Fuchs' endothelial dystrophy, bullous keratopathy, trauma, infection and iatrogenic damage (National Institute for Health and Care Excellence [NICE], 2009).

The most common indications for corneal transplantation in the US for 2012 (Milliman, 2014) were: keratoconus (20%); repeat corneal transplant (12%); and post-cataract surgery oedema (10%).

Limbal stem cell transplantation is used to correct the deficiency of patients with limbal stem cell deficiency, who suffer from a severe loss of vision and photophobia. Donor sources for transplantation are autologous or living-related allogeneic for conjunctival-limbal transplantation; and allogeneic for keratolimbal transplantation (Health Quality Ontario, 2008; Liang et al., 2009).

A recent systematic literature review from 1980─2015 (Ballios et al., 2018) collected data on surgical intervention(s), immunosuppressive agent(s), duration of immunosuppression, percentage with stable ocular surface at last follow-up, mean follow-up time, demographics, and adverse ocular and systemic outcomes. Sixteen reports met the inclusion criteria. There were no randomised controlled studies.  Most studies were retrospective case series, with only three studies being non-comparative prospective case series. Bilateral severe LSCD was the most common disease (50%), and keratolimbal allograft was the most common intervention (80%).

Immunosuppressive regimens showed progression from early studies using oral ciclosporin to later studies using combinations of mycophenolate mofetil and tacrolimus. Most studies included a course of high-dose systemic corticosteroids.

Patients on long-term systemic immunosuppression reported stable ocular surface rates of 70–­80% at last follow-up. Side-effects included hypertension, diabetes mellitus, and biochemical abnormalities, which were managed with pharmacotherapy or stopping the offending agent. There were no cases of mortality related to immunosuppression.

It is clear that patient management would benefit from closer collaboration between opthalmologists and transplant specialists. There is a need for randomised controlled trials and more prospective studies to define the best immunosuppressive regimens for different categories of limbal stem cell deficiency or graft types.

Haematopoietic stem-cell transplantation (HSCT)

Haematopoietic stem-cell transplantation (HSCT) is used primarily to treat haematological and lymphoid cancers. Most autologous transplantations performed worldwide (around two-thirds) are used to treat multiple myeloma or non-Hodgkin’s lymphoma; in contrast, nearly half of all allogeneic transplantations performed worldwide are for the treatment of acute leukaemia (Copelan, 2006).

Autologous HSCT is also used to treat non-malignant diseases, such as autoimmune disorders or amyloidosis. Conditions treated with allogeneic HSCT include: aplastic anaemia, Fanconi’s anaemia, sickle-cell anaemia, thalassaemia major, severe combined immunodeficiency, Wiskott–Aldrich syndrome and inborn errors of metabolism (Copelan, 2006).

In Europe, the main indications for HSCT in 2014 were lymphoid neoplasias (n=20,802; 57%; 11% allogeneic); leukaemias (n=11,853; 33%; 96% allogeneic); solid tumours (n=1458; 4%; 3% allogeneic) and non-malignant disorders (n=2203; 6%; 88% allogeneic) (Passweg et al., 2016).

Table 1 lists the main indications for allogeneic and autologous HSCT in the US in 2010 (Milliman 2014).

Table 1: Indications for haematopoietic stem-cell transplantation in the US in 2010 (Milliman, 2014).

Indications for haematopoietic stem-cell transplantation in the US in 2010