Try a new search

Format these results:

Searched for:

person:horowh01

Total Results:

92


Human granulocytic anaplasmosis during pregnancy: case series and literature review [Case Report]

Dhand, Abhay; Nadelman, Robert B; Aguero-Rosenfeld, Maria; Haddad, Fadi A; Stokes, Daniela P; Horowitz, Harold W
We describe the clinical and laboratory manifestations and pregnancy outcomes of 6 women who received a diagnosis of human granulocytic ehrlichiosis during pregnancy. Human granulocytic ehrlichiosis did not seem to present in a fulminant fashion, and all treated patients had excellent responses to rifampin or doxycycline therapy. Perinatal transmission was documented in 1 neonate, who responded well to treatment. There do not appear to be any long-term adverse sequelae in children born from these pregnancies (mean follow-up duration, 21 months)
PMID: 17682993
ISSN: 1537-6591
CID: 73916

Prevalence of drug-resistant and nonsubtype B HIV strains in antiretroviral-naive, HIV-infected individuals in New York State

Parker, Monica M; Gordon, Daniel; Reilly, Andrew; Horowitz, Harold W; Waters, Mark; Bennett, Ryan; Hallack, Renee; Smith, Joseph; Lamson, Daryl; Aydemir, Aida; Dvali, Natia; Agins, Bruce D; Drusano, George L; Taylor, Jill
The duration of HIV infection is usually unknown for most patients entering into HIV care. Data on the frequency at which resistance mutations are detected in these patients are needed to support practical guidance on the use of resistance testing in this clinical situation. Furthermore, little is known about HIV subtype diversity in much of the United States. Therefore, we analyzed the prevalence of drug resistance mutations and nonsubtype B strains of HIV among antiretroviral-naive individuals presenting for HIV care in New York State between September 2000 and January 2004. Sequences were obtained using a commercial HIV genotyping assay. Seventeen of 151 subjects (11.3%; 95% confidence interval 7.2%-17.3%) had at least one drug-resistance mutation, including 5 subjects with fewer than 200 CD4(+) T cells, indicative of advanced infection. Nucleoside reverse transcriptase inhibitor, non-nucleoside reverse transcriptase inhibitor, and protease inhibitor resistance mutations were detected in 6.6%, 5.3%, and 0.7% of subjects, respectively. Subjects from New York City-based clinics were less likely to have resistant virus than subjects from clinics elsewhere in New York State. Nonsubtype B strains of HIV were detected in 9 (6.0%) individuals and were associated with heterosexual contact. Two nonsubtype B strains from this cohort also carried drug-resistance mutations. These data indicate that drug-resistant virus is frequently detected in antiretroviral-naive individuals entering HIV care in New York State. Furthermore, a diverse set of nonsubtype B strains were identified and evidence suggests that nonsubtype B strains, including those carrying drug-resistance mutations, are being transmitted in New York State
PMID: 17919091
ISSN: 1087-2914
CID: 131448

Intravascular device infections: epidemiology, diagnosis, and management

Gandelman, Glenn; Frishman, William H; Wiese, Cristina; Green-Gastwirth, Vanessa; Hong, Steven; Aronow, Wilbert S; Horowitz, Harold W
Intravascular devices such as pacemakers, implantable cardioverter-defibrillators (ICDs), left ventricular assist devices (LVADs), and prosthetic vascular grafts are life-saving therapies for patients with malignant arrhythmias, heart failure, and various vascular diseases. As indications for their use have increased, so has the prevalence of infectious complications associated with these devices. We present a review of the clinical literature on the epidemiology, diagnosis, and management of infectious complications of these intravascular devices. Most intravascular device infections are thought to result from skin flora contamination during implantation. Infection of the subcutaneous portion of the device can subsequently track to deeper intravascular tissues. Infection that involves the intravascular or intracardiac portion of these devices carries a high morbidity and mortality. Despite appropriate antibiotic therapy, cure of infection is frequently possible only with device removal. Well-designed placebo-controlled, randomized studies evaluating antimicrobial therapy for treatment of intravascular device infections are lacking. In the absence of better information, authorities recommend antibiotics targeted toward cultured organisms for approximately 4 to 6 weeks and device removal
PMID: 17172879
ISSN: 1538-4683
CID: 70650

Once-daily versus twice-daily lopinavir/ritonavir in antiretroviral-naive HIV-positive patients: a 48-week randomized clinical trial

Eron, Joseph J; Feinberg, Judith; Kessler, Harold A; Horowitz, Harold W; Witt, Mallory D; Carpio, Felix F; Wheeler, David A; Ruane, Peter; Mildvan, Donna; Yangco, Bienvenido G; Bertz, Richard; Bernstein, Barry; King, Martin S; Sun, Eugene
The safety, pharmacokinetics, and antiviral activity of lopinavir, a human immunodeficiency virus (HIV) protease inhibitor, coformulated with ritonavir as a pharmacokinetic enhancer were evaluated in 38 antiretroviral-naive patients randomized 1:1 to receive open-label lopinavir/ritonavir at a dose of 800/200 mg once daily or 400/100 mg twice daily, each in combination with stavudine and lamivudine twice daily, for 48 weeks. Over the course of 48 weeks, median predose concentrations of lopinavir exceeded the protein-binding corrected concentration required to inhibit replication of wild-type HIV by 50% in vitro by 40- and 84-fold in the once- and twice-daily groups, respectively. Predose concentrations of lopinavir were more variable in the once-daily group (mean +/- SD, 3.62+/-3.38 microg/mL for the once-daily group and 7.13+/-2.93 microg/mL for the twice-daily group). At week 48, in an intent-to-treat (missing = failure) analysis, 74% of patients in the once-daily group and 79% of patients in the twice-daily group had HIV RNA levels of <50 copies/mL (P=.70). Study drug-related discontinuations occurred in 1 patient in each treatment group. Genotypic resistance testing of 4 patients with HIV RNA levels >400 copies/mL between weeks 24 and 48 demonstrated no protease inhibitor-resistance mutations
PMID: 14722892
ISSN: 0022-1899
CID: 70651

Antifungal susceptibility survey of 2,000 bloodstream Candida isolates in the United States

Ostrosky-Zeichner, Luis; Rex, John H; Pappas, Peter G; Hamill, Richard J; Larsen, Robert A; Horowitz, Harold W; Powderly, William G; Hyslop, Newton; Kauffman, Carol A; Cleary, John; Mangino, Julie E; Lee, Jeannette
Candida bloodstream isolates (n = 2,000) from two multicenter clinical trials carried out by the National Institute of Allergy and Infectious Diseases Mycoses Study Group between 1995 and 1999 were tested against amphotericin B (AMB), flucytosine (5FC), fluconazole (FLU), itraconazole (ITR), voriconazole (VOR), posaconazole (POS), caspofungin (CFG), micafungin (MFG), and anidulafungin (AFG) using the NCCLS M27-A2 microdilution method. All drugs were tested in the NCCLS-specified RPMI 1640 medium except for AMB, which was tested in antibiotic medium 3. A sample of isolates was also tested in RPMI 1640 supplemented to 2% glucose and by using the diluent polyethylene glycol (PEG) in lieu of dimethyl sulfoxide for those drugs insoluble in water. Glucose supplementation tended to elevate the MIC, whereas using PEG tended to decrease the MIC. Trailing growth occurred frequently with azoles. Isolates were generally susceptible to AMB, 5FC, and FLU. Rates of resistance to ITR approached 20%. Although no established interpretative breakpoints are available for the candins (CFG, MFG, and AFG) and the new azoles (VOR and POS), they all exhibited excellent antifungal activity, even for those strains resistant to the other aforementioned agents
PMCID:201160
PMID: 14506023
ISSN: 0066-4804
CID: 70652

A prospective observational study of candidemia: epidemiology, therapy, and influences on mortality in hospitalized adult and pediatric patients

Pappas, Peter G; Rex, John H; Lee, Jeannette; Hamill, Richard J; Larsen, Robert A; Powderly, William; Kauffman, Carol A; Hyslop, Newton; Mangino, Julie E; Chapman, Stanley; Horowitz, Harold W; Edwards, John E; Dismukes, William E
We conducted a prospective, multicenter observational study of adults (n=1447) and children (n=144) with candidemia at tertiary care centers in the United States in parallel with a candidemia treatment trial that included nonneutropenic adults. Candida albicans was the most common bloodstream isolate recovered from adults and children (45% vs. 49%) and was associated with high mortality (47% among adults vs. 29% among children). Three-month survival was better among children than among adults (76% vs. 54%; P<.001). Most children received amphotericin B as initial therapy, whereas most adults received fluconazole. In adults, Candida parapsilosis fungemia was associated with lower mortality than was non-parapsilosis candidemia (24% vs. 46%; P<.001). Mortality was similar among subjects with Candida glabrata or non-glabrata candidemia; mortality was also similar among subjects with C. glabrata candidemia who received fluconazole rather than other antifungal therapy. Subjects in the observational cohort had higher Acute Physiology and Chronic Health Evaluation II scores than did participants in the clinical trial (18.6 vs. 16.1), which suggests that the former subjects are more often excluded from therapeutic trials
PMID: 12942393
ISSN: 1537-6591
CID: 70653

A randomized and blinded multicenter trial of high-dose fluconazole plus placebo versus fluconazole plus amphotericin B as therapy for candidemia and its consequences in nonneutropenic subjects

Rex, John H; Pappas, Peter G; Karchmer, Adolf W; Sobel, Jack; Edwards, John E; Hadley, Susan; Brass, Corstiaan; Vazquez, Jose A; Chapman, Stanley W; Horowitz, Harold W; Zervos, Marcus; McKinsey, David; Lee, Jeannette; Babinchak, Timothy; Bradsher, Robert W; Cleary, John D; Cohen, David M; Danziger, Larry; Goldman, Mitchell; Goodman, Jesse; Hilton, Eileen; Hyslop, Newton E; Kett, Daniel H; Lutz, Jon; Rubin, Robert H; Scheld, W Michael; Schuster, Mindy; Simmons, Bryan; Stein, David K; Washburn, Ronald G; Mautner, Linda; Chu, Teng-Chiao; Panzer, Helene; Rosenstein, Rebecca B; Booth, Jenia
A randomized, blinded, multicenter trial was conducted to compare fluconazole (800 mg per day) plus placebo with fluconazole plus amphotericin B (AmB) deoxycholate (0.7 mg/kg per day, with the placebo/AmB component given only for the first 5-6 days) as therapy for candidemia due to species other than Candida krusei in adults without neutropenia. A total of 219 patients met criteria for a modified intent-to-treat analysis. The groups were similar except that those who were treated with fluconazole plus placebo had a higher mean (+/- standard error) Acute Physiology and Chronic Health Evaluation II score (16.8+/-0.6 vs. 15.0+/-0.7; P=.039). Success rates on study day 30 by Kaplan-Meier time-to-failure analysis were 57% for fluconazole plus placebo and 69% for fluconazole plus AmB (P=.08). Overall success rates were 56% (60 of 107 patients) and 69% (77 of 112 patients; P=.043), respectively; the bloodstream infection failed to clear in 17% and 6% of subjects, respectively (P=.02). In nonneutropenic subjects, the combination of fluconazole plus AmB was not antagonistic compared with fluconazole alone, and the combination trended toward improved success and more-rapid clearance from the bloodstream
PMID: 12746765
ISSN: 1537-6591
CID: 70654

A piece of my mind. Dumbing down

Horowitz, Harold W
PMID: 12636437
ISSN: 0098-7484
CID: 70655

A piece of my mind. The three-legged stool

Horowitz, Harold W
PMID: 12234212
ISSN: 0098-7484
CID: 70656

Analysis of sequences and loci of p44 homologs expressed by Anaplasma phagocytophila in acutely infected patients

Lin, Quan; Zhi, Ning; Ohashi, Norio; Horowitz, Harold W; Aguero-Rosenfeld, Maria E; Raffalli, John; Wormser, Gary P; Rikihisa, Yasuko
Anaplasma phagocytophila is an obligatory intragranulocytic bacterium that causes human granulocytic ehrlichiosis. Immunodominant 44-kDa outer membrane proteins of A. phagocytophila are encoded by a p44 multigene family. In the present study, expression profiles of p44 genes in the blood of acutely infected patients in the year 2000 were characterized. A single p44 gene was predominantly expressed in peripheral blood leukocytes from one patient, while up to 17 different p44 genes were transcribed without a single majority in the other two patients. The cDNA sequences of the central hypervariable region of several p44 genes were identical among the isolates from the three patients and a 1995 A. phagocytophila isolate. A. phagocytophila was isolated by cell culture from all of the three 2000 patients. Genomic Southern blot analysis of the three 2000 and two 1995 A. phagocytophila isolates with probes specific to the most dominant p44 transcript in each patient showed that the p44 loci in the A. phagocytophila genome were conserved. Analysis of the predicted amino acid sequences of 43 different p44 genes including 19 new sequences found in the present study, revealed that five amino acids were absolutely conserved. The hypervariable region was subdivided into five domains, including three extremely hypervariable central domains. These results suggest that variations in the sequences of p44 are not random but are restricted. Furthermore, several p44 genes are not hypermutatable in nature, based on the conservation of gene sequences and loci among isolates obtained 5 years apart
PMCID:120678
PMID: 12149362
ISSN: 0095-1137
CID: 70657