Vertex Pharmaceuticals.

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Late graft rejection impairs the long-term function of organ transplants in children. Previous studies suggest patients with wide variation in tacrolimus levels may have higher rates of late kidney and liver graft rejection. The reproducibility of this finding and impact on graft and recipient survival have not been reported. We investigated factors associated with late rejection > 6 months post-transplant in 144 heart, kidney, liver, and lung transplant recipients (ages 8-18, ≥ 1-yr survivors, receiving tacrolimus-based immunosuppression), comparing late rejectors (n = 61, 42%) to non-rejectors (no rejection > 6 months); groups had similar mean tacrolimus concentrations ≤ 6 months post-transplant. For all organ types, increased standard deviation in intrapatient tacrolimus blood levels was an independent risk factor for late rejection (OR 1.6 [CI 1.1-2.1]; p = 0.02). Each 1-point increase in s.d. > 2 of tacrolimus level > 6 months post-transplant associated with 1.58 increase in hazard of graft loss (p = 0.003). Graft survival (conditional on one-yr survival) was significantly better for those with s.d. < 2 at > 6 months post-transplant: 98% at three and five yr, versus 88%, 70%, at three and five yr, in patients with s.d. > 2 (p = 0.003). In conclusion, high s.d. in serial tacrolimus concentrations associated with increased risk of late rejection and graft loss in pediatric organ transplant recipients, providing opportunities for screening and interventions.

OBJECTIVES: To prospectively study infants with an inconclusive diagnosis of cystic fibrosis (CF) identified by newborn screening (NBS; "CF screen positive, inconclusive diagnosis" [CFSPID]) for disease manifestations. METHODS:Infants with CFSPID and CF based on NBS from 8 CF centers were prospectively evaluated and monitored. Genotype, phenotype, repeat sweat test, serum trypsinogen, and microbiology data were compared between subjects with CF and CFSPID and between subjects with CFSPID who did (CFSPID→CF) and did not (CFSPID→CFSPID) fulfill the criteria for CF during the first 3 years of life.RESULTS: Eighty-two subjects with CFSPID and 80 subjects with CF were enrolled. The ratio of CFSPID to CF ranged from 1:1.4 to 1:2.9 in different centers. CFTR mutation rates did not differ between groups; 96% of subjects with CFSPID and 93% of subjects with CF had 2 mutations. Subjects with CFSPID had significantly lower NBS immunoreactive trypsinogen (median [interquartile range]:77 [61-106] vs 144 mg/L; P , .0001) than did subjects with CF. Pseudomonas aeruginosa and Stenotrophomonas maltophilia were isolated in 12% and 5%, respectively, of subjects with CFSPID. CF was diagnosed in 9 of 82 (11%) subjects with CFSPID (genotype and abnormal sweat chloride = 3; genotype alone = 4; abnormal sweat chloride only = 2). Sweat chloride was abnormal in CFSPID→CF patients at a mean (SD) age of 21.3 (13.8) months. CFSPID→CF patients had significantly higher serial sweat chloride (P , .0001) and serum trypsinogen (P = .009) levels than did CFSPID→CFSPID patients.

Compared to non-viral exacerbations, viral-related exacerbations were associated with worse severity and quality of life scores but similar pulmonary inflammation.

Growing evidence suggests receipt of live‐attenuated viral vaccines after solid organ transplant (SOT) has occurred and is safe and needed due to lapses in herd immunity. A 2‐day consortium of experts in infectious diseases, transplantation, vaccinology, and immunology was held with the objective to review evidence and create expert recommendations for clinicians when considering live viral vaccines post‐SOT. For consideration of VV and MMR post‐transplant, evidence exists only for kidney and liver transplant recipients. For MMR vaccine post‐SOT, consider vaccination during outbreak or travel to endemic risk areas. Patients who have received antiproliferative agents (eg. mycophenolate mofetil), T cell–depleting agents, or rituximab; or have persistently elevated EBV viral loads, or are in a state of functional tolerance, should be vaccinated with caution and have a more in‐depth evaluation to define benefit of vaccination and net state of immune suppression prior to considering vaccination. MMR and/or VV (not combined MMRV) is considered to be safe in patients who are clinically well, are greater than 1 year after liver or kidney transplant and 2 months after acute rejection episode, can be closely monitored, and meet specific criteria of “low‐level” immune suppression as defined in the document.

Risk factors for PFI include Grade A2 rejection, repeated acute rejection, CMV-positive donor, tacrolimus-based regimen and pre-transplant colonization.

Childhood transplant recipients have a 30-times greater cancer incidence versus the general population. Further investigation is needed to guide screening strategies in this at-risk population.