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Query: UMLS:C0027947 (neutropenia)
 17,527 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The occurrence of HSV infection and the effect of prophylaxis with oral acyclovir were evaluated prospectively in 34 consecutive patients undergoing bone marrow transplantation (BMT). All allogeneic BMT procedures involved T-lymphocyte depletion for prevention of graft-vs.-host disease (GVHD). Five HSV-seronegative patients did not receive acyclovir, and they did not develop HSV infection. Oral acyclovir was administered to 15 HSV-seropositive BMT recipients; 14 untreated HSV-seropositive BMT recipients served as a control group. The adult dose of acyclovir was 400 mg three times a day on Days -6 to +14 and 200 mg three times a day on Days +15 to +90. Children received 500 mg/m2 per day divided into three equal doses on Days -6 to +14 and 250 mg/m2 per day again divided into three on Days +15 to +90. In the group on prophylaxis, only one developed HSV infection during the time prior to engraftment. In the reference group, 12 of 14 (85.7%) developed oral HSV infection within 0 to 16 days (median 11 days) after the transplantation. Time for engraftment (duration of neutropenia) was shorter in patients receiving acyclovir. After engraftment, HSV infection was not observed during administration or following discontinuation of acyclovir on Day 90, but occurred in three patients in whom acyclovir was discontinued on Days 25, 35 and 40 after BMT. In the untreated group, two patients had recurrence of HSV infection on Days 40 to 60, and one had two infectious episodes. GVHD occurred in only two recipients, neither of whom had HSV infection. We conclude that the incidence of HSV infection during the period until engraftment in recipients of T-lymphocyte-depleted BMT is high, similar to that reported by others in recipients of whole BMT. Relatively low-dose oral acyclovir administered for 90 days can effectively prevent HSV infections in previously HSV-seropositive BMT recipients and may also shorten the period until engraftment.
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PMID:Prevention of herpes simplex virus (HSV) infection in recipients of HLA-matched T-lymphocyte-depleted bone marrow allografts. 328 77

Two consecutive studies are reported. In study 1, 59 patients with acute leukaemia undergoing remission induction therapy or bone marrow transplantation were given either acyclovir (5 mg/kg) or placebo by intravenous infusion twice daily during the period of neutropenia. All patients were seropositive (greater than or equal to 1:8) for herpes simplex virus. Acyclovir provided total protection against herpes simplex virus infection in bone marrow transplant patients with 0/10 versus 5/10 infections in the placebo group (P = 0.033). For the remission induction therapy group 2/19 on acyclovir developed HSV versus 10/20 receiving placebo (P = 0.018). Only one episode of cytomegalovirus (CMV) infection was seen and this was in a patient on acyclovir. Epstein-Barr virus secretion studies were inconclusive. No varicella zoster virus (VZV) infections were seen. In Study 2, 20 consecutive HSV seropositive (greater than or equal to 1:8) bone marrow transplant recipients received oral acyclovir. Five (25%) developed HSV infections, one of which was in a non-compliant patient, who subsequently developed a fatal infection whilst receiving therapeutic (5 mg/kg 8 hourly) intravenous acyclovir for this HSV infection. Intravenous acyclovir is effective in preventing HSV infections in the immunocompromised host but it seems unlikely that CMV will be amenable to acyclovir in its present formulation.
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PMID:Use of acyclovir for prophylaxis of herpes infections in severely immunocompromised patients. 631 94

Herpes infections continue to be prevalent, especially in immunocompromised patients. Some of these patients will develop resistant HSV infections. Therefore, it is important to explore new treatment options. Animal studies have shown cidofovir to be effective in the treatment and prevention of HSV infections. Human data are limited, with only one randomized, double-blind, placebo-controlled trial performed to date. The results from this study look promising; however, due to the small sample size, a larger clinical trial is warranted. The human data available as case reports are suboptimal in the quality of reporting time frames for resolution of lesions/symptoms and outcomes of therapy. Another problem with the case report data is that the TK status of the herpes simplex isolates was not reported. This would have helped substantiate the acyclovir resistance seen in these patients. It was evident in these case reports that acyclovir resistance can be overcome, as acyclovir-resistant strains became sensitive following cidofovir therapy. This may be because TK(+) viruses have been shown to establish latency more readily than do TK(-) viruses. This pattern suggests that alternating between acyclovir and cidofovir therapies may provide a strategy to manage the emergence of alternatively acyclovir-sensitive and -resistant infections. At present, only the intravenous formulation of cidofovir is commercially available. Advantages of the intravenous formulation include weekly dosing and efficacy. Disadvantages are the complexity of administration and the adverse effect profile. The most common adverse effects with this formulation include nephrotoxicity manifested as proteinuria (12%), and increased creatinine (5%) and neutropenia (15%). Administration of probenecid and NaCl 0.9% hydration are used to reduce the incidence and severity of nephrotoxicity in patients who are receiving cidofovir. Probenecid also has toxicities, including nausea, vomiting, headache, fever, and flushing. The topical formulation of cidofovir looks promising for mucocutaneous HSV infection because it is usually undetectable in the blood following topical administration. Therefore, systemic adverse effects should be minimized. A cidofovir gel product (Forvade, Gilead Sciences) is currently being reviewed by the Food and Drug Administration for the treatment of refractory HSV. Ultimately, more controlled clinical studies are necessary to determine whether routine cidofovir use can be justified in patients with acyclovir-resistant HSV infection.
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PMID:Cidofovir use in acyclovir-resistant herpes infection. 941 91

Oral acyclovir has been demonstrated to prevent reactivation of herpes simplex virus (HSV) infections when administered prophylactically to autologous bone marrow transplant (BMT) recipients or patients undergoing stem cell rescue therapy. Oral valacyclovir, which is converted in the body to acyclovir, has greater oral bioavailability than oral acyclovir and compared with oral acyclovir yields similar acyclovir plasma concentrations with less frequent (twice-daily) dosing. This study compared the efficacy of oral valacyclovir with that of oral acyclovir at preventing HSV mucositis in BMT recipients. A total of 60 HSV-1-positive patients scheduled for BMT or stem cell rescue therapy were treated prophylactically with valacyclovir 500 mg twice daily until resolution of neutropenia. Data from these patients were compared with those of a historical control group of 60 patients who had received acyclovir 600 mg every 6 h until resolution of neutropenia or acyclovir 125 mg/m(2) intravenously every 6 h. The results show that none of the patients developed oral or oropharyngeal HSV infection while receiving either treatment. Of the 60 patients receiving valacyclovir, 38 (63%) completed treatment without the need for intravenous acyclovir compared with 12 of 60 (20%) patients in the acyclovir group. Additionally, the total number of doses of drug administered to the valacyclovir group was significantly less than the number received by patients in the acyclovir group. No serious adverse events occurred in either group of patients. This study demonstrates that oral valacyclovir and acyclovir are comparably effective and safe in preventing reactivation of HSV infections in autologous BMT and stem cell recipients. The less frequent dosing schedule with valacyclovir compared with acyclovir offers a potential advantage for patients undergoing BMT who frequently suffer with severe mucositis and have difficulty taking oral medications.
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PMID:Clinical utility of oral valacyclovir compared with oral acyclovir for the prevention of herpes simplex virus mucositis following autologous bone marrow transplantation or stem cell rescue therapy. 1459 93