Hyperferritinaemia following intrauterine transfusions for Rh isoimmunisation.

Intrauterine transfusion is one of the mainstays of treatment in isoimmunised pregnancies guided by the changes in middle cerebral artery Doppler of the fetus. The common postnatal complications associated with Rh isoimmunisation are high unconjugated bilirubin requiring blood exchange transfusions, cholestasis due to bile inspissation, thrombocytopenia and anaemia. Hyperferritinaemia is an uncommon adverse effect observed in Rh isoimmunised pregnancies. In this case report, we describe the clinical course of a Rh isoimmunised neonate with hyperferritinaemia and transfusion acquired cytomegalovirus disease which resolved. Iron chelation therapy was not necessary.

Resistant Cytomegalovirus Infection After Renal Transplantation: Literature Review.

BACKGROUND: Resistant cytomegalovirus (R-CMV) is an emerging problem in the renal transplantation population. The most frequent CMVs are high-resistance mutations (UL97 gene). METHODS: We describe our experience in management of R-CMV after renal transplant at our center (2012-2016). RESULTS: We encountered 3 cases of R-CMV infection after renal transplant (all primary infections). All 3 patients received induction therapy with corticosteroids, tacrolimus, and mycophenolate mofetil. The first patient (basiliximab induction, preemptive CMV) developed CMV replication on day +53, which responded poorly both to standard-dose valganciclovir (vGCV) and high-dose ganciclovir (GCV) (creatinine clearance [CrCl] >70 mL/min; vGCV 900 mg twice daily for 50 days and GCV 7.5 mg/kg twice daily for 8 days). Hematologic toxicity occurred. The R-CMV test was positive and foscarnet (FOS) was initiated (90 mg/kg twice daily for 21 days). The second patient presented CMV infection (day +30, thymoglobulin induction, CMV prophylaxis), which was not controlled with the high dose (CrCl 23 mL/min; GCV 3.5 mg/kg twice daily and vGCV 900 mg twice daily), resulting in severe neutropenia. R-CMV was detected and FOS initiated (FOS 50 mg/kg twice daily for 7 days and 50 mg/kg every 2 days for 13 days). The third patient's infection occurred on day +22 (basiliximab induction, preemptive CMV). Standard-dose vGCV was uneffective (CrCl >70 mL/min, vGCV 900 mg twice daily) and it did not respond to the high dose (GCV 7.5 mg/kg twice daily and vGCV 2700 mg/d). Moderate hematologic toxicity occurred. R-CMV was diagnosed and FOS treatment begun (FOS 70 mg/kg per day for 2 weeks). CONCLUSIONS: Resistant CMV infection may be severe due to viral infection and side effects of high-dose antiviral treatment. We presented 3 cases requiring the use of FOS in the absence of response or toxic effects from the usual treatment, with an optimal sustained response (temporary in case 2) and without serious side effects.

High-dose Valganciclovir Treatment for Resistant Cytomegalovirus Colitis due to UL97 and UL54 Mutations.

We report the first case of a ganciclovir-resistant cytomegalovirus (CMV) involving the gastrointestinal tract that was successfully treated with high-dose valganciclovir. A kidney transplant recipient developed drug-resistant CMV colitis which was initially treated with valganciclovir, but his CMV was found to have major resistance to ganciclovir and cidofovir due to UL97 and UL54 mutations. The patient was switched to intravenous foscarnet 40 mg/kg given every twelve hours. However, foscarnet had to be discontinued after 4 days of treatment due to acute kidney injury. Patient was restarted on valganciclovir at a higher target dose of 1800 mg twice a day based on the creatinine clearance. CMV became undetectable 2 weeks after valganciclovir treatment was completed. High-dose valganciclovir along with immune suppression reduction may be a treatment option for CMV colitis with ganciclovir resistance due to dual UL97 and UL54 gene mutations.

Successful Treatment of Carbapenemase-Producing Pandrug-Resistant Klebsiella pneumoniae Bacteremia.

New antibiotic options are urgently needed for the treatment of carbapenem-resistant Enterobacteriaceae infections. We report a 64-year-old female with prolonged hospitalization following an intestinal transplant who developed refractory bacteremia due to a serine carbapenemase-producing pandrug-resistant isolate of Klebsiella pneumoniae. After failing multiple antimicrobial regimens, the patient was successfully treated.

Treatment of DIHS/DRESS syndrome with combined N-acetylcysteine, prednisone and valganciclovir--a hypothesis.

BACKGROUND: Drug-induced hypersensitivity syndrome/drug reaction with eosinophilia and systemic symptoms (DIHS/DRESS) is a rare and severe adverse drug reaction with an associated mortality of 10-20%. Clinical worsening despite discontinuation of the culprit drug is considered a characteristic feature of DIHS/DRESS. Besides the early recognition of the syndrome and discontinuation of its causative drug, the mainstay of treatment is systemic corticosteroids. Nevertheless, treatment of severe DIHS/DRESS is not well defined, as corticosteroids may sometimes not be effective, and decreasing the dose may be associated with flaring of the disease. CASE REPORT: A 38-year-old woman with high fever, malaise, abdominal pain, rash, and elevated liver enzymes received immediate high-dose N-acetylcysteine, because acetaminophen hepatotoxicity was suspected. N-acetylcysteine administration was associated with a significant clinical improvement. However, within the next week DIHS/DRESS syndrome was diagnosed, which explained all the symptoms, and which was subsequently treated with prednisone and valganciclovir. CONCLUSIONS: New options necessary to improve treatment of severe DIHD/DRESS have to consider its sequential pathogenetic mechanisms. N-acetylcysteine might neutralize the drug-derived reactive metabolites, which are responsible for protein adduct formation and specific T cell stimulation, and replete the glutathione stores that counterbalance oxidative stress. Prednisone might inhibit lymphoproliferation and valganciclovir might prevent complications related to HHV-6 reactivation. We therefore propose the unprecedented combination of N-acetylcysteine, prednisone and valganciclovir as a treatment option for DIHS/DRESS.

Incidence and characterization of cytomegalovirus resistance mutations among pediatric solid organ transplant patients who received valganciclovir prophylaxis.

BACKGROUND: Drug-resistant cytomegalovirus (CMV) infections can cause significant morbidity among high-risk transplant recipients. OBJECTIVES: The aims of this study were to determine the incidence and clinical consequences of CMV mutations conferring ganciclovir resistance in pediatric solid organ transplant (SOT) patients who received valganciclovir oral solution or tablets for prophylaxis of CMV disease. Recombinant CMV mutants were also generated to assess the role of two UL97 mutations of unknown significance. STUDY DESIGN: Genotypic resistance mutations and CMV viral load were sought in blood samples from pediatric SOT recipients who received valganciclovir prophylaxis for 100 days. Recombinant viruses containing novel CMV UL97 mutations were generated using a bacterial artificial chromosome containing the CMV genome to assess ganciclovir susceptibility. RESULTS: Overall, four known resistance UL97 mutations were observed in blood samples from 2 of 46 patients during the study with no development of CMV disease. Two UL97 changes (M615V and V466G) of unknown significance and one UL97 mutation (C603R) associated with ganciclovir resistance, but not yet confirmed by marker transfer, were also detected. Recombinant viruses containing these novel mutations were generated to assess ganciclovir susceptibility. The M615V recombinant virus was susceptible to ganciclovir while the V466G and C603R mutant viruses displayed 3.5-fold and 3.6-fold decreases in susceptibility, respectively. CONCLUSIONS: The low incidence of ganciclovir resistance-associated mutations and the absence of clinical consequences associated with drug-resistant viruses observed in this pilot study should encourage the design of larger clinical trials aimed at evaluating the efficacy of valganciclovir prophylaxis and treatment in the pediatric setting.

Successful valganciclovir treatment of post-transplant cytomegalovirus infection in the presence of UL97 mutation N597D.

Mutations in the human cytomegalovirus (CMV) UL97 protein kinase are the most common mechanism of ganciclovir (GCV) resistance in the clinical setting. A CMV strain with a previously unrecognized UL97 mutation N597D was identified in the blood of a heart transplant recipient who experienced a persistent CMV infection with high viral loads accompanying pain and fever while receiving valganciclovir (valGCV) therapy. The N597D mutation was transferred by mutagenesis to an antiviral sensitive CMV strain for analysis of antiviral susceptibility by standardized phenotypic assay. Recombinant phenotyping showed N597D conferred a less than twofold increase in GCV IC(50) compared to the sensitive control strain. Despite the presence of this mutation, valGCV eventually resolved the infection after 6 weeks of therapy. A subsequent CMV reactivation was also responsive to valganciclovir. This case illustrates the diversity of UL97 mutations in the codon segment 590-607 usually associated with GCV resistance, with some mutations producing minimal levels of resistance that do not preclude a therapeutic response to the drug. Accurate interpretation of genotypic test results ultimately requires experimental determination of the level of resistance conferred by newly discovered UL97 mutations.

Valganciclovir is safe and effective as pre-emptive therapy for CMV infection in allogeneic hematopoietic stem cell transplantation.

Despite significant advances in prevention and therapy, cytomegalovirus (CMV) infection continues to be an important cause of morbidity and mortality in the hematopoietic stem cell transplant (HSCT) recipient. The standard drug for pre-emptive therapy is intravenous ganciclovir (GCV). Valganciclovir (VGC), the oral pro-drug of GCV, has excellent bioavailability and is ideal for oral therapy. Since March 2002, VGC was adopted in our center for outpatient pre-emptive therapy in all patients undergoing allogeneic HSCT. Fifty-two allogeneic HSCT recipients were followed weekly via Digene hybrid capture assay. Patients with a positive assay were treated with VGC 900 mg p.o. b.i.d. x 14 days followed by 900 mg p.o. QD until at least 7 days after a negative test. Eighteen patients (14 sib, four MUD) had 30 episodes of CMV DNA detection treated with oral VGC. Median duration of therapy was 21 days (range 10-21 days). The rate of response was 93% (28/30) as confirmed by a negative assay within 14 days. No significant toxicity was encountered. Two patients failed oral VGC. One case of CMV enteritis was diagnosed in a patient with acute GVHD. Pre-emptive therapy of CMV infection with oral VGC is safe and effective in allogeneic HSCT recipients.

Corneal absorption and anterior chamber pharmacokinetics of dipeptide monoester prodrugs of ganciclovir (GCV): in vivo comparative evaluation of these prodrugs with Val-GCV and GCV in rabbits.

AIM: The overall aim of this study was to evaluate the corneal absorption of dipeptide monoester prodrugs of ganciclovir (GCV) and compare these results with L-valine-GCV and GCV. Another aim was to evaluate the pharmacokinetics of these prodrugs in aqueous humor. METHODS: A well was placed on the cornea of anesthetized New Zealand albino rabbits with linear probes implanted in the aqueous humor. Two hundred microlitres (200 microL) of a 0.43% w/v (saturation concentration) solution of GCV and equimolar concentrations of its prodrugs, VGCV, glycine-valine-GCV (GVGCV), valine-valine-GCV (VVGCV), and tyrosine-valine- GCV (YVGCV), were placed in the corneal well and were allowed to diffuse for a period of 2 h. Subsequently, the drug solution was aspirated and the well removed. Samples were collected every 20 min throughout the infusion and postinfusion phases and were analyzed by high-performance liquid chromatography to determine the aqueous humor concentrations. RESULTS: Area under the concentration time profile (AUC)infinity and maximum concentration (Cmax) of YVGCV were found to be higher than other prodrugs. AUC of total GCV obtained from YVGCV administration was found to be twelvefold more than AUC of GCV and 6.2-fold more than AUC obtained with total GCV from VGCV administration. VVGCV also exhibited 3.2 times higher AUC relative to VGCV. Also, AUC and Cmax of regenerated GCV from YVGCV was 8.6 and 4.9 times more than GCV, respectively. VVGCV did not produce higher concentrations of GCV. Elimination half-life of regenerated GCV from YVGCV administration was observed to be 157 min. CONCLUSIONS: YVGCV and VVGCV exhibited superior corneal absorption and bioavailability, in comparison with GVGCV, VGCV, and GCV. Such facilitated absorption of prodrugs may be a result of a combination of transcellular passive diffusion and peptide transporter (PEPT1)-mediated transport across the corneal epithelium.

Prednisone-free maintenance immunosuppression-a 5-year experience.

Concern persists that prednisone-free maintenance immunosuppression in kidney transplant recipients will be associated with an increase in late allograft dysfunction and graft loss. We herein report 5-year follow-up of a trial of prednisone-free maintenance immunosuppression. From October 1, 1999, through January 31, 2005, at our center, 589 kidney transplant recipients were treated with a protocol incorporating discontinuation of their prednisone on postoperative day 6. At 5 years, actuarial patient survival was 91%; graft survival, 84%; death-censored graft survival, 92%; acute rejection-free graft survival, 84% and chronic rejection-free graft survival, 87%. The mean serum creatinine level (+/-SD) at 1 year was 1.6 +/- 0.6; at 5 years, 1.7 +/- 0.8. In all, 86% of kidney recipients with functioning grafts remain prednisone-free as of April 30, 2005. As compared with historical controls, recipients on prednisone-free maintenance immunosuppression had a significantly lower rate of a number of complications, including cataracts (p < 0.001), posttransplant diabetes mellitus (p < 0.001), avascular necrosis (p = 0.001), and fractures (p = 0.004). We conclude that prednisone-related side effects can be minimized in a protocol incorporating prednisone-free maintenance immunosuppression. Five-year graft outcome remains good.

Therapeutic developments in cytomegalovirus retinitis.

The incidence of cytomegalovirus (CMV) retinitis in AIDS has declined significantly due to the use of highly active antiretroviral therapy (HAART). However, patients with HIV, especially those failing HAART, may still suffer with CMV retinitis, which can lead to significant loss of vision and blindness. Ganciclovir has traditionally been considered the recommended treatment for CMV retinitis; however, due to side effects and the possibility of developing viral resistance, other agents may be preferred in certain situations. Foscarnet, which has similar efficacy to ganciclovir but a different side effect profile, is more difficult to administer and is less well-tolerated. Intravenous cidofovir, which may be more effective than either iv. ganciclovir or foscarnet, can also be used as a first line agent; however, it is associated with toxicity (renal and ocular) and thus needs careful use. Local therapy for CMV retinitis has been a significant advance. The intraocular ganciclovir implant has the highest efficacy of the approved agents and is well-tolerated. Fomivirsen, an oligonucleotide injected intravitreally, is a newly approved agent which offers alternative treatment. Intravitreal ganciclovir or foscarnet, although not approved, have been used successfully in some patients especially those with recurrent or refractory disease. The development of new anti-CMV agents has been stalled by the decreased incidence of the disease. Valganciclovir, a prodrug of ganciclovir, offers excellent oral bioavailability and is the closest to approval of all the new anti-CMV drugs. High ganciclovir blood levels are achieved without the complications associated with the requirement for long-term iv. access. The monoclonal antibody (mAb) MSL-109, did not offer a significant advantage when added to traditional anti-CMV therapy. Development plans of other agents such as cyclic HPMPC and lobucavir have been put on hold by their respective manufacturers. Adefovir is a nucleotide analogue that possesses anti-CMV activity, but is currently only being pursued for the treatment of hepatitis B virus. Other compounds possessing significant anti-CMV activity, including BAY 38-4766 and GW1263W94 are still in the early stages of development.