Reactivation of varicella zoster virus (VZV) is a common event in patients undergoing allogeneic bone marrow transplantation (BMT) and may lead to life-threatening complications. We retrospectively analyzed the incidence, clinical outcome, and risk factors for VZV infections occurring within the first 5 years of transplantation in 100 consecutive adults undergoing allogeneic BMT between 1992 and 1997. Forty-one patients (41%) developed VZV reactivation a median of 227 days (range 45-346 days) post-transplantation. Twelve percent of VZV reactivation occurred in the first 100 days and 88% within the first 24 months. Among those who survived for 2 or more years after transplantation (n = 47), 59% developed VZV infection. Forty percent of patients with VZV reactivation required admission with a mean hospital stay of 7.2 days. Two patients developed encephalitis, and 1 died despite antiviral therapy. The most frequent complications were post-herpetic neuralgia and peripheral neuropathy (68%). Thoracic dermatomal zoster represented 41% of the infections; disseminated cutaneous involvement was observed in 17% of patients. No clinical or epidemiologic risk factors were associated with recurrence. Administration of ganciclovir for prevention of cytomegalovirus infection delayed the onset of VZV infection beyond 4 months (P = .06). In a further subset analysis, patients with a limited chronic graft-versus-host disease (GVHD) had a lower estimated incidence of VZV reactivation compared with those with extensive chronic GVHD (P = .11). We conclude that complications from reactivation of VZV infection are common and associated with considerable morbidity and mortality in patients undergoing allogeneic BMT.

A potential association between human herpesvirus 6 (HHV-6) and cytomegalovirus (CMV) following kidney transplantation was explored by retrospectively testing serial serum specimens for HHV-6 IgG and IgM antibody. HHV-6 reactivation occurred in 35 (66%) of 53 transplant recipients. Fungal or parasitic opportunistic infections, graft rejection or loss, and mortality were not associated with HHV-6 reactivation. HHV-6 reactivation was associated with primary CMV infection (P=.001) and CMV syndrome (P=.003) and with trends for CMV-related hepatitis (P=.095), CMV-related neutropenia (P=.104), and serious CMV disease (P=.085). After controlling for CMV immune globulin (CMVIG) prophylaxis, the association between HHV-6 reactivation and primary CMV infection and syndrome remained significant (P=.002 and 0.006, respectively). The reduction in CMV syndrome among those receiving CMVIG prophylaxis remained significant (P=.007) after controlling for HHV-6 reactivation. HHV-6 reactivation in kidney transplant recipients at risk for primary CMV infection is associated with CMV infection and CMV-related disease, and these effects are independent of CMVIG prophylaxis.

A systematic evaluation of the attributable mortality of Stenotrophomonas maltophilia bacteremia was undertaken in a matched, retrospective, case-control study. We determined the attributable mortality rate (26.7%) and mortality risk ratio (an 8-fold increase) of S. maltophilia bacteremia. The attributable mortality rate for S. maltophilia bacteremia is similar to the attributable mortality rate for other nosocomial bloodstream infections.

Use of macrolides as part of an initial therapeutic regimen appears to be associated with shorter LOS.

In hospitalized hematology-oncology patients, culture of blood drawn through either the central catheter or peripheral vein shows excellent negative predictive value. Culture of blood drawn through an indwelling central venous catheter has low positive predictive value, apparently less than from a peripheral venipuncture. Therefore, a positive result from a catheter needs clinical interpretation and may require confirmation. However, the use of a catheter to obtain blood for culture may be an acceptable method for ruling out bloodstream infections.

To explore the possible interaction between human herpesvirus 6 (HHV-6) and cytomegalovirus (CMV) in patients who have undergone organ transplantation, stored serum samples from 139 orthotopic liver transplant recipients were tested for HHV-6 immunoglobulin (Ig) G and IgM antibodies. HHV-6 reactivation occurred in 87 patients (62.6%) and was associated with CMV disease (P=.01), severe CMV-associated disease (P=.01), older age (P=.005), and use of muromonab-CD3 (Orthoclone; Orthobiotech) as treatment for rejection (P=.02). Trends for an association between HHV-6 reactivation and invasive fungal disease (P=.12), bacteremia (P=.10), and graft loss (P=.12) were seen. In a multivariate analysis of risk factors for severe CMV-associated disease, HHV-6 reactivation (relative risk [RR], 3.5; 95% confidence interval [CI], 1.2-10.2; P=.02), CMV donor-positive-recipient-negative match (RR, 5.7; 95% CI, 2.5-13.2; P<.001), and elevated serum creatinine level (P<.0001) were independent predictors. HHV-6 reactivation is associated with severe CMV-associated disease in liver transplant recipients.

In critically ill surgical patients, cultures of blood drawn through a catheter are less specific than those obtained from a peripheral venipuncture. Both types of cultures have an excellent negative predictive value. Positive predictive value of cultures of blood drawn through a catheter is low and, when obtained from a central line, statistically less than from a peripheral venipuncture. Additional cultures seem to be necessary for the proper interpretation of a positive culture drawn through a catheter in critical care patients.

Reactivation of latent VZV remains a significant cause of morbidity after SCT. Twenty-five percent or more of patients undergoing SCT will experience zoster within the first year after transplant. Short-course (o1 year) prophylaxis with acyclovir has been shown to be effective, but compliance with five times daily dosing may be problematic. We conducted a randomized, double-blind, placebo-controlled trial of valacyclovir (VACV) 1000 mg twice daily from 4 through 24 months after SCT for the prevention of VZV. Fifty-three VZV-seropositive transplant recipients (17 auto-SCT, 36 allo-SCT) were randomized at a median of 163 days after SCT. In a modified intent-to-treat analysis of 49 patients who took study drug, 0 of 22 in the VACV arm experienced zoster reactivation, compared with 6 of 26 (23%) in the placebo arm (P ¼ 0.025). Thirty-two subjects completed therapy through the second year post transplant or first episode of zoster. Adverse events resulting in discontinuation were more frequent in the placebo group (5 of 26 vs 3 of 27 for placebo and study drug, respectively). VACV at a dose of 1000 mg twice daily through 24 months after transplant is well tolerated and effective in suppressing shingles after SCT.