Increase in short-term risk of rejection in heart transplant patients receiving granulocyte colony-stimulating factor

Neutropenia in pediatric solid organ transplant

Neutropenia is generally defined as an absolute neutrophil count in the circulation of less than 1500/mm³ and occurs in up to 25%-30% of pediatric solid organ transplant recipients (SOT) within the first year after transplantation. In the SOT population, neutropenia is most often a result of drug-induced bone marrow suppression but can also be secondary to viral infection, nutritional deficiencies, lymphoproliferative infiltrate, and inherited causes. Outcomes for patients with neutropenia vary by degree of neutropenia and type of solid organ transplant. Management of neutropenia should begin by addressing the underlying cause, including reducing or removing medications when appropriate, treating infections, and addressing nutrient deficiencies; however, consultation with an experienced pediatric hematologist and use of granulocyte colony-stimulating factor (G-CSF) may be helpful in some cases. Overall, data on clinical outcomes for G-CSF use remain limited, but observational studies may support its use in patients with infections or severe neutropenia.

Short- and long-term impact of neutropenia within the first year after kidney transplantation

The aim of this retrospective single-center study was to investigate short- and long-term impact of neutropenia occurring within the first year after kidney transplantation, with a special emphasis on different neutropenia grades. In this unselected cohort, 225/721 patients (31%) developed 357 neutropenic episodes within the first year post-transplant. Based on the nadir neutrophil count, patients were grouped as neutropenia grade 2 (<1.5-1.0*10⁹ /L; n=105), grade 3 (<1.0-0.5*10⁹ /L; n=65), and grade 4 (<0.5*10⁹ /L; n=55). Most neutropenia episodes were presumably drug-related (71%) and managed by reduction/discontinuation of potentially responsible drugs (mycophenolic acid [MPA] 51%, valganciclovir 25%, trimethoprim/sulfamethoxazole 19%). Steroids were added/increased as replacement for reduced/discontinued MPA. Granulocyte colony-stimulating factor was only used in 2/357 neutropenia episodes (0.6%). One-year incidence of (sub)clinical rejection, one-year mortality as well as long-term patient and graft survival were not different among patient without neutropenia and neutropenia grade 2/3/4. However, the incidence of infections was about 3-times higher during neutropenia grade 3 and 4, but not increased during grade 2. In conclusion, neutropenia within the first year after kidney transplantation represents no increased risk for rejection and has no negative impact on long-term patient and graft survival. Adding/increasing steroids as replacement for reduced/discontinued MPA might supplement management of neutropenia.

Favorable outcomes after heart transplantation in Barth syndrome

BACKGROUND

Barth Syndrome (BTHS) is a rare, X-linked disease characterized by cardioskeletal myopathy and neutropenia. Comparative outcomes after heart transplantation have not been reported.

METHODS

We identified BTHS recipients across 3 registries (Pediatric Heart Transplant Study Registry [PHTS], Barth Syndrome Research Registry and Repository, and Scientific Registry of Transplant Recipient-Pediatric Health Information System) and matched them 1:4 to non-BTHS, male heart transplant (HT) recipients listed with dilated cardiomyopathy in PHTS. Demographics and survival data were analyzed for all recipients, whereas post-HT infection, malignancy, allograft vasculopathy, and acute rejection were only available for analysis for individuals with PHTS data.

RESULTS

Forty-seven BTHS individuals with 51 listings and 43 HTs (including 2 re-transplants) were identified. Age at primary HT was 1.7 years (IQR: 0.6-4.5). Mechanical circulatory support at HT was common (ventricular assist device 29%, extracorporeal membrane oxygenation 5%). Over a median follow-up of 4.5 years (IQR 2.7-9.1), survival for BTHS HT recipients was no different than non-BTHS HT recipients (HR 0.91, 95% CI 0.40-2.12, p = 0.85). Among those with PHTS data (n = 28), BTHS HT recipients showed no difference in freedom from infection (HR 0.64, 0.34-1.22; p = 0.18), malignancy (HR 0.22, 0.02-2.01, p = 0.18), and allograft vasculopathy (HR 0.58, 0.16-2.1, p = 0.41). Freedom from acute rejection (HR 0.39, 0.17-0.86, p = 0.02) was greater for BTHS HT recipients despite similar use of induction (61 vs 73%, p = 0.20), steroids at 30-days (75 vs 62%, p = 0.27), and dual/triple drug immunosuppression at 1-year (80 vs 84%, p = 0.55).

CONCLUSIONS

In this largest cohort yet reported, individuals with BTHS have equivalent survival with less acute rejection and no difference in infection or malignancy after HT. When indicated, HT for individuals with BTHS is appropriate.

Impact of G-CSF Therapy on Leukopenia and Acute Rejection Following Kidney Transplantation

BACKGROUND

Leukopenia is a common problem after kidney transplantation. The therapeutic approach typically includes a reduction of the immunosuppressive therapy, which is associated with an increased risk of rejection and allograft loss. Granulocyte colony-stimulating factor (G-CSF) is used as a therapeutic option to raise the leukocyte blood count; however, the effect on acute rejections is controversial.

OBJECTIVE

The goal of this study is to examine the incidence of acute rejections following G-CSF therapy.

METHODS

We retrospectively evaluated patients with leukopenia following kidney transplantation and GCSF therapy between January 2007 and December 2017 at our center compared to controls with matched minimal leucocyte blood count in a matched pair analysis.

RESULTS

We identified 12 patients, who received G-CSF therapy with a cumulative dose of 10.74 µg/kg body weight over a time frame of 4.3 days. G-CSF therapy resulted in a significantly shorter time period with leucocytes <3,000/µL (9.5 vs. 16.6 days), but also trended towards an increased risk of rejection within the next 30 days with three patients in the G-CSF group and no patient in the control group (p=0.06) developing an acute biopsy-proven rejection. Infection and mortality rate in the subsequent year were not different between groups.

CONCLUSION

G-CSF therapy decreases the duration of leukopenia post-kidney transplantation, but may also increase the risk of an acute rejection.

Longterm Outcomes of Living Donor Liver Transplantation for Glycogen Storage Disease Type 1b

Glycogen storage disease (GSD) type 1b (Online Mendelian Inheritance in Man [OMIM] 232220) is an autosomal recessive inborn error of carbohydrate metabolism caused by defects in glucose-6-phosphate translocase. GSD1b patients have severe hypoglycemia with several clinical manifestations of hepatomegaly, obesity, a doll-like face, and neutropenia. Liver transplantation (LT) has been indicated for severe glucose intolerance, poor metabolic control (PMC), and poor growth (PG). We retrospectively reviewed 11 children with GSD1b who underwent living donor liver transplantation (LDLT) at the National Center for Child Health and Development in Tokyo, Japan. Between November 2005 and December 2018, 495 children underwent LDLT with an overall 10-year patient and graft survival of 90.6% and 88.9%, respectively. Of these, LT was indicated for 11 patients with GSD1b. All patients are doing well with the stabilization of glucose intolerance and decreased hospitalization for infectious complications. Demand for granulocyte colony-stimulating factor significantly decreased. However, although LT stabilized the blood glucose level, the platelet function was not improved. The posttransplant developmental quotient (DQ) remained similar to the pretransplant DQ without deterioration. LDLT is a feasible procedure for GSD1b patients with regard to the longterm prognosis. LT should be considered for patients with severe glucose intolerance to protect the cognitive function against hypoglycemic encephalopathy and to ameliorate PMC and PG.

Lung transplant outcomes are influenced by severity of neutropenia and granulocyte colony-stimulating factor treatment

Although neutropenia is a common complication after lung transplant, its relationship with recipient outcomes remains understudied. We evaluated a retrospective cohort of 228 adult lung transplant recipients between 2008 and 2013 to assess the association of neutropenia and granulocyte colony-stimulating factor (GCSF) treatment with outcomes. Neutropenia was categorized as mild (absolute neutrophil count 1000-1499), moderate (500-999), or severe (<500) and as a time-varying continuous variable. Associations with survival, acute rejection, and chronic lung allograft dysfunction (CLAD) were assessed with the use of Cox proportional hazards regression. GCSF therapy impact on survival, CLAD, and acute rejection development was analyzed by propensity score matching. Of 228 patients, 101 (42.1%) developed neutropenia. Recipients with severe neutropenia had higher mortality rates than those of recipients with no (adjusted hazard ratio [aHR] 2.97, 95% confidence interval [CI] 1.05-8.41, P = .040), mild (aHR 14.508, 95% CI 1.58-13.34, P = .018), or moderate (aHR 3.27, 95% CI 0.89-12.01, P = .074) neutropenia. Surprisingly, GCSF treatment was associated with a higher risk for CLAD in mildly neutropenic patients (aHR 3.49, 95% CI 0.93-13.04, P = .063), although it did decrease death risk in severely neutropenic patients (aHR 0.24, 95% CI 0.07-0.88, P = .031). Taken together, our data point to an important relationship between neutropenia severity and GCSF treatment in lung transplant outcomes.