BK Viremia as a Predictor of Hemorrhagic Cystitis in Adults During the First 100 Days After Allogeneic Hematopoietic Stem Cell Transplantation.

In a retrospective case-control study, we aimed to assess the utility of plasma BK viral load value to predict hemorrhagic cystitis (HC) symptoms after allogeneic hematopoietic stem cell transplantation (alloHSCT). During first 100 post-transplantation days of all adult AlloHSCT recipients at the University of Nebraska Medical Center from October 1, 2011, to June 30, 2014, 8 unexcluded cases of HC were identified and matched with 88 unexcluded unaffected control cases. Viral loads were determined for archived DNA extracted from plasma collected within 3 weeks before transplantation until ∼100 days after transplantation. Clinical factors, time of onset of BK viremia, and BK viral load were compared between case and control subjects to identify risks for HC. Symptomatic HC occurred in 8/96 (8.3%) of patients at a median of 34 days after transplantation. BK viremia either before or during symptoms was detected in all 8 (100%) HC patients and in 20/88 (22.7%) of control subjects. BK viremia was detected at a median of 8 days before HC clinical symptoms. The log of first positive viral load was not a statistically significant predictor (P = .17) of symptomatic BK. Median BK viral load peak was significantly higher for 8 patients with HC versus 20 viremic patients without HC (6.66 vs 5.06; P < .052). Further study is required to evaluate the predictive value of the BK viral load for HC.

Endemic fungal infections in solid organ and hematopoietic cell transplant recipients enrolled in the Transplant-Associated Infection Surveillance Network (TRANSNET).

BACKGROUND: Invasive fungal infections are a major cause of morbidity and mortality among solid organ transplant (SOT) and hematopoietic cell transplant (HCT) recipients, but few data have been reported on the epidemiology of endemic fungal infections in these populations. METHODS: Fifteen institutions belonging to the Transplant-Associated Infection Surveillance Network prospectively enrolled SOT and HCT recipients with histoplasmosis, blastomycosis, or coccidioidomycosis occurring between March 2001 and March 2006. RESULTS: A total of 70 patients (64 SOT recipients and 6 HCT recipients) had infection with an endemic mycosis, including 52 with histoplasmosis, 9 with blastomycosis, and 9 with coccidioidomycosis. The 12-month cumulative incidence rate among SOT recipients for histoplasmosis was 0.102%. Occurrence of infection was bimodal; 28 (40%) infections occurred in the first 6 months post transplantation, and 24 (34%) occurred between 2 and 11 years post transplantation. Three patients were documented to have acquired infection from the donor organ. Seven SOT recipients with histoplasmosis and 3 with coccidioidomycosis died (16%); no HCT recipient died. CONCLUSIONS: This 5-year multicenter prospective surveillance study found that endemic mycoses occur uncommonly in SOT and HCT recipients, and that the period at risk extends for years after transplantation.

False-positive Aspergillus galactomannan assay in solid organ transplant recipients with histoplasmosis.

Post-transplantation histoplasmosis may be acquired via inhalation, may result from endogenous reactivation, or may be derived from the allograft. The Histoplasma and Aspergillus enzyme-linked immunoassays are increasingly being relied upon for rapid diagnosis of fungal infections, especially in immunocompromised patients. We describe 4 cases of solid organ transplant recipients who had histoplasmosis and a falsely positive Aspergillus galactomannan (GM) obtained from the serum or bronchoalveolar lavage (BAL) fluid. We also report our experience, testing for Histoplasma antigen (Ag) in specimens positive for Aspergillus GM. From January 2007 through December 2010, of 2432 unique patients who had positive Aspergillus GM tests, 514 (21%) were tested for Histoplasma Ag, and 27 were found to be positive. Most specimens that tested positive for both Aspergillus and Histoplasma were obtained by BAL. False-positive tests for Aspergillus GM can occur in immunosuppressed patients who have histoplasmosis, and may obscure the correct diagnosis.

Seronegative naturally acquired West Nile virus encephalitis in a renal and pancreas transplant recipient.

West Nile virus (WNV), a single-stranded RNA flavivirus, has spread across the United States since arriving in 1999. While asymptomatic or self-limited in a majority of patients, WNV can cause a severe neuroinvasive disease, which occurs more often in transplant recipients with chronic immunosuppression. Diagnosis of acute WNV infection usually relies on serologic identification of immunoglobulin M (IgM) specific for the virus. We report a fatal case of naturally acquired WNV encephalitis in a renal and pancreas transplant recipient who was seronegative for WNV-specific IgM but had detectable WNV RNA by nucleic acid amplification testing (NAAT) several weeks after the onset of symptoms. This case demonstrates the importance of using both serologic assays and NAAT for WNV in transplant recipients with the clinical suspicion of encephalitis.

Seroprevalence of West Nile virus infection in solid organ transplant recipients.

BACKGROUND: Of people infected with mosquito-borne West Nile virus (WNV), <1% develop neuroinvasive disease (NID). Population studies suggest that people older than 65 years may be at higher risk for neurologic symptoms. It has been suggested that solid organ transplant (SOT) recipients are also at higher risk for WNV NID, but definitive serologic and epidemiologic data are lacking. METHODS: A serologic screening survey, using a US Food & Drug Administration-approved enzyme-linked immunosorbant assay to detect WNV immunoglobulin-G (IgG) antibody responses in cohorts of SOT recipients and non-immunocompromised controls, was undertaken at a large Midwestern university organ transplant center in the aftermath of the summer 2003 WNV regional outbreak. Hemagglutination-inhibition testing was used to confirm WNV IgG-positive results and differentiate them from positive results caused by Saint Louis encephalitis virus, another flavivirus that is endemic in the Midwestern US. FINDINGS: The rate of WNV IgG-seropositive responses did not differ between SOT recipients and non-immunocompromised controls, and were 12% and 10%, respectively. Retrospective chart review showed no documented WNV NID in the seropositive SOT recipients, suggesting an incidence of WNV NID may be as low as 0.7% in this population. INTERPRETATION: Asymptomatic WNV infection is common among immunocompromised SOT patients, occurring as often as it does in non-immunocompromised controls. Our data indicated that severe WNV NID is less frequent in SOT patients, contrary to what has been suggested in other studies.

Sepsis and solid organ transplantation.

Approximately seventy patients undergo solid organ transplantation (SOT) every day in the United States. Sepsis remains the first or second most common cause of death in transplant recipients, depending on the allograft type. The rapid diagnosis and treatment of sepsis is critical to ensure improved survival outcome in this special patient population. However, these patients frequently lack the classic systemic inflammatory response syndrome (SIRS), commonly seen in the immunocompetent patients. In order to minimize delays in the diagnosis of sepsis in SOT recipients, it is paramount to recognize the specific risk factors for infection associated with each allograft type. In addition, the particular surgical techniques involved in each type of transplantation may be closely related to the clinical manifestations of the infection process. This correlation can further advance the diagnosis and treatment of sepsis. In conclusion, precocious diagnosis, rapid initiation of antibiotics, surgical correction when necessary, and reduction of immunosuppression, are the mainstream approach to sepsis in the SOT patient. The recent developments in severe sepsis are discussed in the context of the transplant recipient.

Histoplasmosis in solid organ transplant recipients at a large Midwestern university transplant center.

Histoplasma capsulatum sporadically causes severe infections in solid organ transplant (SOT) patients in the Midwest, but it has been an unusual infection among those patients followed at the University of Nebraska Medical Center (UNMC), located at the western edge of the 'histo belt.' Nine SOT patients with histoplasmosis are described (6 renal or renal-pancreas and 3 liver recipients) who developed severe histoplasmosis over a recent 2.5-year period at UNMC. Symptoms started a median of 11 months (range, 1.2-90 months) after organ transplant and consisted primarily of fever, cough, shortness of breath, and malaise or fatigue present for approximately 30 days prior to medical evaluation. All patients had an abnormal chest radiograph and/or computed tomographic scan. Tacrolimus was the main immunosuppressant in all 9 patients, along with prednisone or mycophenolate. Dacluzimab or thymoglobulin had been given around the time of transplant in 6 of 9. None was treated for an episode of acute rejection within 2 months before onset of histoplasmosis, although 2 were on high-dose immunosuppression after recent transplants. Diagnosis was made by culture in 8 of the 9 patients, with positive serum and urine histoplasma antigen tests in all 9 cases. From 1997 to 2001, during a period of relative quiescence of the disease in the general population, the rate of clinical histoplasmosis among SOT patients at UNMC was estimated at 0.11%, whereas during 2002 through the first half of 2004, the rate rose 17-fold to 1.9%. Histoplasmosis can present as a prolonged febrile illness with subacute pulmonary symptoms in a cohort of SOT patients, despite the absence of a regional outbreak.

The current state of infectious disease: a clinical perspective on antimicrobial resistance.

The medical community is in the midst of a wake-up call. No longer can antimicrobial use be taken for granted. The overprescribing of antimicrobials has taken its toll and the consequence has been a precipitous increase in drug-resistant pathogens seen over the last decade. Pharmaceutical companies and researchers are no longer able to keep a step ahead of these resistant pathogens with new antimicrobial agents. The primary care clinician is now faced with complicated treatment issues for many infectious diseases that were once considered uncomplicated. The mechanisms leading to the development of antimicrobial resistance in bacteria is discussed in addition to an overview of the most common drug-resistant pathogens.

The outpatient management of febrile neutropenia in cancer patients.

Treatment of fever and neutropenia in cancer patients has been recognized for 30 years as a medical emergency, requiring prompt in-hospital evaluation and institution of broad-spectrum intravenous (i.v.) antibiotics. This action was deemed necessary due to the high frequency of life-threatening infections in febrile neutropenic patients, with no way to distinguish patients who are infected from those who are not. In recent years, it has become clear that not all neutropenic cancer patients are at the same level of risk for developing severe infections or life-threatening complications during neutropenia. Those who are at low risk may be candidates for treatment outside the hospital setting, either with i.v. regimens or potent oral antibiotics. The identification of low-risk febrile neutropenic patients and the specific outpatient approaches that have been tested to date are discussed. Outpatient management of fever during neutropenia could obviously be much less costly than standard inpatient care and could improve quality of life for low-risk patients undergoing cancer therapy.

A controlled seroprevalence survey of primate handlers for evidence of asymptomatic herpes B virus infection.

Herpes B virus (BV) is a common cause of recurring mucocutaneous infections in monkeys of the genus Macaca. Like its human counterpart, herpes simplex virus (HSV), BV establishes lifelong latency and can be reactivated from infected monkeys symptomatically or asymptomatically. Incidental infection of humans handling BV-shedding monkeys can result in fatal meningoencephalitis. To determine whether humans exposed to infected monkeys can acquire asymptomatic BV infections, 480 subjects were evaluated in a controlled seroprevalence study. Sera from 321 primate handlers, including many with repeated injuries inflicted by Macaca monkeys, and 159 people never exposed to monkeys were tested in blinded fashion by both competition ELISA and Western blot to determine the prevalence of BV and HSV seropositivity. Although 293 persons proved positive for HSV antibodies, no primate handlers or control subjects showed BV-specific antibody responses. There is no serologic evidence that BV causes asymptomatic infections in humans.

Monotherapy for fever and neutropenia in cancer patients: a randomized comparison of ceftazidime versus imipenem.

PURPOSE: To compare the efficacy of ceftazidime and imipenem monotherapy for fever and neutropenia, and to determine whether fewer antimicrobial modifications (additions or changes) are required by the broader-spectrum agent, imipenem. PATIENTS AND METHODS: Adult and pediatric patients undergoing chemotherapy for solid tumors, leukemias, or lymphomas were randomized to receive open-label ceftazidime or imipenem on presentation with fever and neutropenia. Success with or without modifications of the initial antibiotic was defined as survival through neutropenia; failure was death due to infection. Comparisons were based on numbers of modifications made to each monotherapy during the course of neutropenia, in patients stratified as having unexplained fever or a documented infection. RESULTS: Among 204 ceftazidime and 195 imipenem recipients, the overall success rate with or without modification was more than 98%, regardless of initial antibiotic regimen. Modifications occurred in half of all episodes, primarily in patients with documented infections on either monotherapy. Antianaerobic agents were more frequently added to ceftazidime (P < .001), but addition of other antibiotics, including vancomycin and aminoglycosides, was similar between the two monotherapy groups. Imipenem therapy was associated with significantly greater toxicity, manifested by Clostridium difficile-associated diarrhea and by nausea and vomiting, which required discontinuation of imipenem in 10% of recipients. CONCLUSION: Ceftazidime and imipenem are both effective in the management of fever and chemotherapy-related neutropenia, provided that modifications are made in response to clinical and microbiologic data that emerge during the course of neutropenia. Imipenem, despite its broader antimicrobial spectrum, does not significantly decrease the overall need for antibiotic modifications and is more often complicated by gastrointestinal toxicity.

Infectious complications in the immunocompromised host. The antimicrobial armamentarium.

The treatment of infectious complications in the cancer patient has evolved as a consequence of the developments in cancer chemotherapy, which significantly impair immune function. Broad-spectrum, single-agent antibiotics have replaced more cumbersome multidrug regimens for empiric coverage of fever and neutropenia in many institutions. The use of new, potent oral antibiotics may be a next step toward further simplifications. Several new antivirals have come into clinical use in the past decade, and reports of viral resistance to the standard agent, acyclovir, have come forth. Increasing experience with new (and older) antifungal and antiparasitic agents has given a better understanding of the use of these drugs for both prophylaxis and treatment. This overview includes a critical appraisal of the attributes and limitations of current antibiotics, antivirals, antifungals, and antiparasitic agents for the immunocompromised host.

Induction and enhancement of immune responses to herpes simplex virus type 2 in humans by use of a recombinant glycoprotein D vaccine.

A vaccine for a chronic or recurrent viral infection should induce immune responses that protect against primary disease or that augment preexisting defenses sufficiently to diminish the likelihood of disease recurrence or progression. Such a vaccine was sought for genital herpes, a sexually transmitted infection of epidemic proportion. Vaccine containing recombinant herpes simplex virus type 2 glycoprotein D expressed in CHO cells was given repeatedly and safely to 24 human volunteers. In previously uninfected subjects, the vaccine induced primary antigen-specific and neutralizing antibody responses nearing or exceeding those seen at entry in subjects with genital herpes. Primary cellular immune responses were also evoked. Vaccination of previously seropositive subjects boosted antibody titers to levels that remained, for > or = 1 year, severalfold above those attained in recurrent genital herpes. Either the quantity or mode of presentation of antigen permitted this vaccine to exhibit previously unachieved immunogenicity, which may prove adequate for antiviral immunoprophylaxis or treatment of genital herpes.

Resistance of viruses to antiviral drugs.

In recent years, substantial advances in antiviral therapy have been made; however, in the immunocompromised host, antiviral drug resistance is becoming an issue of increasing clinical importance. Understanding the mechanism of action of antiviral agents, especially those used to treat herpesvirus infections, may enable us to design new therapeutic agents and better treatment regimens to deal with antiviral drug resistance.

Acyclovir suppression of frequently recurring genital herpes. Efficacy and diminishing need during successive years of treatment.

Forty-seven patients with frequently recurring genital herpes participated in one or more of five sequential trials of oral suppressive therapy with 200 mg of acyclovir three times daily from four to 12 months' duration. The prolonged use of acyclovir was extremely well tolerated, and treatment efficacy was sustained through successive studies. Recurrences in eight patients with repeated treatment "failures" were more effectively suppressed with higher doses of acyclovir. All patients experienced recurrent infections after the treatments were completed; however, the mean time to recurrence following each treatment period became progressively longer, and resumption of suppressive therapy was no longer warranted for ten patients. These data indicate the efficacy and safety of chronic suppressive therapy with acyclovir and the value of interrupting prolonged treatment to assess its further need.

Nontransmural versus transmural myocardial infarction. A morphologic study.

Although "nontransmural" and "transmural" are morphologic terms used widely to distinguish patients with myocardial infarction, controversy exists as to their meaning regarding clinical course. For this study, a transmural infarct was defined as one that involves essentially the full thickness of the ventricular wall, and nontransmural was defined as something less. The purpose of this study was to identify true morphologic nontransmural acute (less than 21 days old) infarcts at autopsy and compare them with transmural (full-thickness) infarcts in age-matched subjects, for clinical and pathologic similarities and differences. Among the autopsy subjects, comparing 35 nontransmural and 35 transmural infarcts, there was no significant difference with regard to subjects' race or sex, chest pain, arrhythmias, heart block, or cause of death; transmural myocardial infarctions did have a higher frequency of new Q waves (30 of 35 versus six of 35, p less than 0.001) and presented more often with increasing dyspnea. At autopsy, there were no significant differences regarding heart weight, location of infarcts, severity of coronary disease, age of acute infarct, or total size of infarct (18 percent of left ventricle for nontransmural versus 22 percent for transmural). There was, however, a significantly greater tendency for those with nontransmural infarct to have evidence of prior infarction at autopsy (27 of 35 versus 19 of 35, p less than 0.05). Acute coronary thrombi in the distribution of the infarct were significantly more common among transmural myocardial infarcts (32 of 35 versus 18 of 35, p less than 0.001). Morphologically, the nontransmural infarcts showed mural involvement ranging from 20 to 90 percent of the left ventricle, and histologically showed more contraction band (i.e., reflow) injury (57 percent with more than 30 percent contraction band necrosis) compared with transmural infarcts (32 percent with more than 30 percent contraction band necrosis) (p less than 0.05). Fatal nontransmural and transmural infarcts have major clinical and pathologic similarities, but differences in number of prior infarcts, type of necrosis, and occurrence of coronary thrombi suggest differing pathophysiology. The heterogeneity of both transmural and nontransmural infarcts likely accounts for existing differences among clinical studies regarding prognosis. Although this classification system has value in the clinical setting, that at times it represents an imprecise oversimplification of infarct type should be recognized in assessing individual patients.