Kalen L. Jacobson

Adenovirus infections in adult recipients of blood and marrow transplants

Adenoviruses are increasingly recognized pathogens that affect blood and marrow transplant (BMT) recipients. Experiences with 2889 adult BMT recipients were reviewed to study the incidence, clinical spectrum, risk factors for dissemination, response to therapy, and outcome of adenovirus infections. Eight-five patients (3%) were diagnosed by means of culture (n=85) or culture and histopathological examination (n=6). Nine patients had asymptomatic viruria, and 76 had symptomatic infections, which included upper respiratory tract infection (n=20), enteritis (n=18), hemorrhagic cystitis (n=10), pneumonia (n=15), and disseminated disease (n=13). The overall mortality rate was 26%. A higher mortality rate was observed among patients with pneumonia (73%) and disseminated disease (61%). Risk factors for dissemination included receipt of an allogeneic transplant, presence of graft-versus-host disease (GVHD), and receipt of concurrent immunosuppressive therapy. Intravenous ribavirin was not associated with an appreciable benefit among 12 patients who received this treatment. In conclusion, adenovirus infections are an important cause of morbidity and mortality in adult BMT recipients, particularly allogeneic transplant recipients with GVHD who are receiving immunosuppressive therapy. The need for an effective, nontoxic antiviral therapy is apparent.

Respiratory syncytial virus upper respiratory tract illnesses in adult blood and marrow transplant recipients: combination therapy with aerosolized ribavirin and intravenous immunoglobulin.

Respiratory syncytial virus (RSV) is an important cause of serious respiratory illness in blood and marrow transplant (BMT) recipients. In some subsets of these immunocompromised patients, RSV upper respiratory illnesses frequently progress to fatal viral pneumonia. The frequency of progression to pneumonia is higher during the pre-engraftment than during the post-engraftment period. Once pneumonia develops, the overall mortality is 60–80%, regardless of the treatment strategy. We performed a pilot trial of therapy of RSV upper respiratory illnesses using aerosolized ribavirin and IVIG (500 mg/kg every other day), with the goal of preventing progression to pneumonia and death. Two dosages of ribavirin were used: a conventional regimen (6 g/day at 20 mg/ml for 18 h/day) and a high-dose short-duration regimen (6 g/day at 60 mg/ml for 2 h every 8 h). Fourteen patients were treated for a mean of 13 days (range: 7–23 days). In 10 (71%) patients, the upper respiratory illness resolved. The other four (29%) patients, three of whom were in the pre-engraftment period, developed pneumonia, which was fatal in two. The most common adverse effect was psychological distress at being isolated within a scavenging tent. In conclusion, prompt therapy of RSV upper respiratory illnesses in BMT recipients with a combination of aerosolized ribavirin and IVIG was a safe and promising approach to prevent progression to pneumonia and death. Bone Marrow Transplantation (2000) 25, 751–755.

Late Cytomegalovirus Pneumonia in Adult Allogeneic Blood and Marrow Transplant Recipients

To assess the impact of antiviral prophylaxis during the first 3 months after transplantation on the frequency, timing, and outcome of cytomegalovirus (CMV) pneumonia during the first year, 541 adult allogeneic blood and marrow transplant recipients were evaluated. Thirty-four patients (6.3%) developed 35 episodes of CMV pneumonia at a mean of 188 days after transplantation, with an associated mortality rate of 76%. Twenty-six episodes (74%) occurred late (after day 100). Of the patients with late CMV pneumonia almost all (92%) had chronic graft vs. host disease or had received T cell-depleted transplants. Fourteen late CMV pneumonias (54%) were associated with serious concurrent infections, and 100% of these episodes were fatal. In conclusion, although the frequency of CMV pneumonia in the early posttransplantation period may be substantially reduced by prophylaxis, CMV continues to be a major cause of morbidity and mortality in the late period. Some subsets of patients need more prolonged surveillance and prophylaxis and/or preemptive therapy.

Rapidly Growing Mycobacteria Clinical and Microbiologic Studies of 115 Cases

We analyzed clinical and microbiologic features of 115 cases involving rapidly growing mycobacteria (RGM) isolated at the University of Texas M.D. Anderson Cancer Center, Houston (2000-2005) and identified by 16S ribosomal RNA gene sequencing analysis. At least 15 RGM species were included: Mycobacterium abscessus (43 strains [37.4%]), Mycobacterium fortuitum complex (33 strains [28.7%]), and Mycobacterium mucogenicum (28 strains [24.3%]) most common, accounting for 90.4%. Most M abscessus (32/43) were isolated from respiratory sources, whereas most M mucogenicum (24/28) were from blood cultures. Antimicrobial susceptibility tests showed that M abscessus was the most resistant species; M mucogenicum was most susceptible. From blood and catheter sources, 46 strains (40.0%) were isolated; 44 represented bacteremia or catheter-related infections. These infections typically manifested high fever (mean temperature, 38.9 degrees C), with a high number of RGM colonies cultured. All infections resolved with catheter removal and antibiotic therapy. Six strains (M abscessus and M fortuitum only) were from skin, soft tissue, and wound infections. There were 59 strains from respiratory sources, and 28 of these represented definitive to probable infections. Prior lung injuries and coisolation of other pathogenic organisms were common. Overall, 78 RGM strains (67.8%) caused true to probable infections without direct deaths.

Clinical Significance and Epidemiologic Analyses of Mycobacterium avium and Mycobacterium intracellulare among Patients without AIDS

ABSTRACT The clinical significance and prevalence of Mycobacterium avium and Mycobacterium intracellulare were analyzed in a cohort of 7,472 patients who, from 1999 to 2003, sought care at the University of Texas M.D. Anderson Cancer Center, Houston, and had cultures performed for mycobacteria. Patients were stratified for age, sex, and underlying diseases, and bacteria were identified by 16S rRNA gene sequencing. M. avium was isolated in 62 (0.83%) of 7,472 patients and M. intracellulare in 65 (0.87%). Clinically, only 10 of the 62 (16.2%) patients with M. avium had probable to definite evidence of infection, whereas the majority (83.8%) had weak evidence of infection. Sex and age did not affect the isolation or infection of M. avium. Hematological tumors predisposed to M. avium colonization but not infection. In contrast, 41 of the 65 (63.1%) patients with M. intracellulare had probable to definite infection, a level much higher than those with M. avium (P < 0.001). M. intracellulare was more prevalent in women (1.33% of 3,311) than in men (0.50% of 4,161) (P < 0.001), and underlying diseases had no effect in women. Men with lung cancer had a higher prevalence (1.37%) than men without (0.34%) (4.0-fold; P < 0.001), but it was similar to that in women. A marked age trend for the isolation of M. intracellulare among women was noted: 0.27% (1-fold) for ages of <50 years, 0.85% (3.1-fold) for ages 50 to 59 years, 1.50% (5.6-fold) for ages 60 to 69 years, and 3.74% (13.9-fold) for ages ≥70 years (trend, P < 0.001). The combined rate for women ≥50 was 1.86% (95% confidence interval [1.30 to 2.42%]) (6.9-fold). Together, these results suggest that, among non-AIDS patients, M. intracellulare is more pathogenic and tends to infect women increasingly beyond menopause (age ≥50 years) regardless of underlying disease. The prevalence rate of 1.86% in postmenopausal women suggests the need to further investigate the public health significance of M. intracellulare.

Cytomegalovirus pneumonia in adult autologous blood and marrow transplant recipients

CMV pneumonia is a major cause of morbidity and mortality among allogeneic BMT recipients. To assess the frequency, timing, risk factors and response to therapy of CMV pneumonia among autologous BMT recipients, we reviewed our experience with 795 patients. Sixteen (2%) patients were diagnosed with CMV pneumonia. The frequency was higher among patients who were seropositive than those who were seronegative (3.3% vs 0%, P = 0.008). Among seropositive patients, the frequency was higher among patients with hematological malignancies than patients with solid tumors (5.0 % vs1.0%, P = 0.019). Eleven cases occurred <30 days, and five cases occurred >100 days post transplant. The overall CMV pneumonia-related mortality rate was 31%. Seven (78%) of nine patients treated with ganciclovir and IVIG prior to respiratory failure survived; neither of two patients treated after respiratory failure survived. Four of five (80%) untreated patients survived. In conclusion, CMV is a not infrequent cause of pneumonia among autologous BMT recipients. Risk factors include CMV seropositivity and an underlying hematological malignancy. A favorable response hinges on the prompt initiation of therapy. The survival of 25% of the patients without antiviral therapy suggests that the isolation of CMV from a BAL specimen occasionally reflects oropharyngeal contamination or that CMV pneumonia may sometimes be self-limited in more immunocompetent autologous BMT recipients. Bone Marrow Transplantation (2001) 27, 877–881.

Cytomegalovirus Pneumonia in Adults with Leukemia: An Emerging Problem

Cytomegalovirus (CMV) pneumonia is reportedly unusual among adults with leukemia who have not undergone transplantation. To assess the frequency of CMV pneumonia and its outcome during the present time, we reviewed the experience of 2136 hospitalized adults with leukemia. Sixty-one patients (2.9%) had CMV pneumonia diagnosed. The frequency doubled from 1.4% in 1992--1994 to 2.8% in 1995--1997 (P<.05). Fifty-four patients (89%) had received treatment with an immunosuppressive chemotherapeutic regimen that contained fludarabine (n=37), high-dose cytoxan (n=17), or both (n=10), and 15 patients (25%) had received granulocyte transfusions that were stimulated with hematopoietic growth factors from unscreened donors. The overall CMV pneumonia--associated mortality rate was 57%. Among autopsied patients who had leukemia, the frequency of CMV pneumonia increased from 0%, 2.3%, and 0% in 1992, 1993, and 1994, respectively, to 4.6%, 6.5%, and 16% in 1995, 1996, and 1997, respectively (P<.05). CMV has emerged as an important cause of life-threatening pneumonia in adults with leukemia who have received potent immunosuppressive therapies and stimulated granulocyte transfusions from unscreened donors.

Treatment of febrile neutropenic patients with cancer who require hospitalization: A prospective randomized study comparing imipenem and cefepime

The objective of the current study was to compare the efficacy and safety of imipenem and cefepime in the treatment of adult patients with cancer who had fever and neutropenia requiring hospitalization according to Infectious Disease Society of America criteria.

Respiratory syncytial virus infections in autologous blood and marrow transplant recipients with breast cancer: combination therapy with aerosolized ribavirin and parenteral immunoglobulins

Scant data are available concerning the impact and response to therapy of respiratory syncytial virus (RSV) infections in patients undergoing autologous blood and marrow transplantation (BMT) for breast cancer. During eight winter seasons from 1992–1993 to 1999–2000, nine (4%) of 249 such patients were hospitalized with RSV infections. Six patients, including all five patients who were early post transplant in the pre-engraftment period, developed pneumonia and were treated with a combination of aerosolized ribavirin and IVIG. Among five patients with pneumonia in whom therapy was initiated prior to respiratory failure, one (20%) died. The sixth patient, in whom therapy was initiated after respiratory failure developed, also died. In total, two (1%) patients, both of whom were in the pre-engraftment period, died of progressive pneumonia. In conclusion, RSV is a significant cause of life-threatening pneumonia in autologous BMT recipients with breast cancer during the early post-transplant period, and accounted for a substantial portion of the overall transplant-related mortality, which in recent years has been minimal. Bone Marrow Transplantation (2001) 28, 271–275.

Legionella pneumonia in cancer patients

Legionella is an important cause of nosocomial and community-acquired pneumonia in both immunocompetent and immunosuppressed patients worldwide; however, the clinical course and optimal antibiotic therapy of Legionella pneumonia (LP) in patients with cancer is uncertain. We studied retrospectively the risk factors, clinical manifestations, and outcome of 49 cancer patients with a positive Legionella culture or direct fluorescent antibody (DFA) over a 13-year period (1991-2003). The majority of patients (82%) had an underlying hematologic malignancy, and 37% were bone marrow transplant recipients; 80% of the patients had active malignancy. Lymphopenia (47%), use of systemic corticosteroids (41%), and chemotherapy (63%) were the most common underlying conditions. The laboratory diagnosis was established by positive Legionella culture (n = 8, 16%), DFA (n = 29, 59%), or both (n = 12, 25%). In 4 patients (8%), a positive DFA was deemed to represent false-positive results. There was no temporal or geographic clustering of cases. The majority of the cases had multilobar (61%) or bilateral (55%) pulmonary involvement. The mean time to response to therapy was 8 days; 18 patients (37%) developed complications requiring prolonged duration of treatment (mean, 25 d). The case-fatality rate was 31%. Two patients had relapse of LP despite appropriate therapy. Improved outcome, especially in those with severe pneumonia, seemed to correlate with the use of a combination of antibiotics. LP is an uncommon infection in our patient population but is associated with significant morbidity and mortality. Treatment of LP in cancer patients may require a prolonged course with a regimen that includes a newer macrolide or quinolone. Abbreviations: BCYE = Buffered Charcoal Yeast Extract, BMT = bone marrow transplant, CDC = Centers for Disease Control and Prevention, DFA = direct fluorescent antibody, GVHD = graft-versus-host-disease, LP = Legionella pneumonia, MDACC = The University of Texas M. D. Anderson Cancer Center.