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L N Slater

Publications and source records attributed to L N Slater.

34 records · Page 2Linked to original sources
PubMed1993

Clinical experience with HIV-infected patients at the University of Oklahoma Health Sciences Center: an update.

We reviewed the course of 545 human immunodeficiency virus (HIV)-infected patients seen between 1983 and March 30, 1991. A majority were Caucasian homosexual or bisexual men, while parenteral drug abusers represented a smaller proportion than seen nationwide. In the 274 patients with the acquired immunodeficiency syndrome (AIDS), the distribution of AIDS-defining conditions was generally consistent with those reported in studies from elsewhere in the United States. However, toxoplasmosis remained relatively uncommon. There was a slightly higher incidence of disseminated histoplasmosis compared to other studies. HIV encephalopathy (AIDS dementia) was likely underdiagnosed. Although data suggested prolongation of the asymptomatic phase of HIV infection, median survival after AIDS diagnosis remained approximately 12 months.

AIDS-Related Opportunistic Infections↗
PubMed1992

Immunocytochemical identification of Rochalimaea henselae in bacillary (epithelioid) angiomatosis, parenchymal bacillary peliosis, and persistent fever with bacteremia.

We report the immunocytochemical identification of Rochalimaea henselae, a newly recognized fastidious, Gram-negative, Warthin-Starry-positive organism, as the common pathogen in bacillary angiomatosis (BA), bacillary peliosis (BP) of the liver and spleen, and persistent fever with bacteremia in immunocompromised patients. Immunogenic proteins of the R. henselae strain isolated from the blood of a febrile immunocompromised patient with BP of the liver were used to produce primary immune serum in rabbits. Using immunocytochemical procedures, the polyclonal antiserum reacted strongly not only with the immunizing strain of the bacteria, but also with other blood isolates of R. henselae (five cases) from both immunocompromised and immunocompetent patients and with the organisms present in the tissue lesions of cutaneous BA (five cases) and BP of the liver (two cases) and spleen (one case). The blood isolates and BA and BP tissue samples were obtained from widely separated geographic areas. The antiserum was weakly cross-reactive with cultures of Rochalimaea quintana, an organism closely related to R. henselae, but this reactivity was eliminated by specific adsorption. The antiserum did not cross-react with the Warthin-Starry-positive organisms associated with cat scratch disease (Afipia felis), syphilis (Treponema pallidum), Lyme disease (Borrelia burgdorferi) or chronic active gastritis (Helicobacter pylori). Likewise, the antiserum did not identify organisms in eight cases of Kaposi's sarcoma, a disorder of immunocompromised patients that is clinically similar to BA. Further studies are needed to determine the prevalence of this newly recognized organism as well as its possible involvement in other angioproliferative diseases.

Acquired Immunodeficiency Syndrome↗
PubMed1992

Rochalimaea henselae sp. nov., a cause of septicemia, bacillary angiomatosis, and parenchymal bacillary peliosis.

Nine strains of Rochalimaea spp. that were isolated from patients over a period of 4.5 years were characterized for their enzyme activities, cellular fatty acid compositions, and DNA interrelatedness among Rochalimaea spp., Bartonella bacilliformis, and Afipia felis (cat scratch disease bacillus). All except one isolate, which was Rochalimaea quintana, were determined to belong to a newly proposed species, Rochalimaea henselae sp. nov. After recovery from clinical material, colonies required 5 to 15 days of incubation to become apparent. Cells were small, gram-negative, curved bacilli and displayed twitching motility. Enzyme specificities for amino acid and carbohydrate substrates showed that R. henselae could be distinguished from Rochalimaea vinsonii by L-arginyl-L-arginine and L-lysyl-L-alanine peptidases, but not all strains could be distinguished from R. quintana on the basis of peptidases or carbohydrate utilization. R. henselae also closely resembled R. quintana in cellular fatty acid composition, with both consisting mainly of C18:1, C18:0, and C16:0 fatty acids. However, the strains of R. henselae all contained C18:0 in amounts averaging greater than or equal to 22%, in contrast to R. quintana, which contained this cellular fatty acid in amounts averaging 16 and 18%. DNA hybridization confirmed the identification of one clinical isolate as R. quintana and showed a close interrelatedness (92 to 100%) among the other strains. Under optimal conditions for DNA reassociation, R. henselae showed approximately 70% relatedness to R. quintana and approximately 60% relatedness to R. vinsonii. Relatedness with DNA from B. baciliformis was 43%. R. henselae was unrelated to A. felis. R. henselae is the proposed species of a newly recognized member of the family Rickettsiaceae, which is a pathogen that may be encountered in immunocompromised or immunocompetent patients. Prolonged fever with bacteremia or vascular proliferative lesions are clinical manifestations of the agent.

Adult↗
PubMed1992

Murine antibody responses distinguish Rochalimaea henselae from Rochalimaea quintana.

Rochalimaea henselae causes persistent bacteremia, bacillary angiomatosis, and parenchymal bacillary peliosis. Detection of a specific antibody response to R. henselae infection may represent an alternative to cultivation as a means of diagnosis. We assessed the specificity of induced murine antibodies for antigens from R. henselae and the closely related species R. quintana. Groups of CD-1 mice were inoculated with whole organisms of six strains of R. henselae and two of R. quintana. Pre- and postinoculation blood specimens were collected. Enzyme immunosorbent assays were performed by using as antigens preparations of immunogenic proteins from one isolate of R. henselae or from the R. quintana type strain. These demonstrated high specificity of R. henselae-induced antibodies for proteins of R. henselae and of R. quintana-induced antibodies for proteins of R. quintana. Protein preparations extracted from all of the strains were separated electrophoretically. After their transfer to membranes, immunoblots were performed by using 1:1,000 dilutions of all of the pre- and postinoculation sera in combination with proteins from all of the strains. Preinoculation sera had minimal reactivity. All of the R. henselae-induced immune sera reacted with numerous proteins of all of the R. henselae strains but cross-reacted minimally with proteins of R. quintana. Immune sera from R. quintana-inoculated mice had similar species specificity. An immunofluorescence assay was developed by using antiserum to one strain of R. henselae. A 1:1,000 dilution yielded fluorescence with all strains of R. henselae but with none of R. quintana, Bartonella bacilliformis, or Afipia felis. Acinetobacter calcoaceticus subsp. anitratus was also unreactive with a dilution of 1:500. A 1:10 dilution yielded weak fluorescence with R. quintana but none with Staphylococcus epidermidis.

Animals↗
PubMed1992

Polypoid endobronchial lesions. A manifestation of bacillary angiomatosis.

Polypoid endobronchial lesions occurred in a patient with acquired immunodeficiency syndrome (AIDS) with recent fever, skin lesions, lymphadenopathy, lung infiltrates, and pleural effusions. His condition improved with antimicrobials and vincristine. After therapy ceased, skin lesions recurred and gastroesophageal mucosal lesions developed. Bacillary angiomatosis was identified during retrospective analysis of skin and endobronchial biopsy specimens.

Acquired Immunodeficiency Syndrome↗
PubMed1992

Rochalimaea henselae causes bacillary angiomatosis and peliosis hepatis.

BACKGROUND: Recent studies have demonstrated that a newly described agent of persistent bacteremia, Rochalimaea henselae, and the agent of bacillary angiomatosis are both closely related to Rochalimaea quintana. Bacillary peliosis hepatis seemed likely to have the same etiologic agent as bacillary angiomatosis. We sought these pathologic changes in patients from whom R henselae was cultivated. METHODS: For two patients whose histopathologic findings we reviewed, additional light and electron microscopy were performed. Their bacterial isolates were compared by electrophoretic patterns of outer membrane proteins, restriction endonuclease digestion patterns of DNA, and reaction with murine antiserum. RESULTS: A previously reported human immunodeficiency virus-infected man with persistent bacteremia due to R henselae was found to have bacillary peliosis hepatis. Rochalimaea henselae was also isolated from the spleen of a woman receiving immunosuppressive therapy after allogeneic renal transplantation. She had developed fever, liver and spleen nodules, and periaortic lymphadenopathy. Bacillary peliosis of her liver and spleen, as well as bacillary angiomatosis of liver, spleen, and a lymph node, were found. The bacterial isolates had comparable electrophoretic patterns of outer membrane proteins and of restriction endonuclease-digested DNA, which differed from the respective patterns of R quintana. Murine antisera raised to the first isolate reacted strongly with the second by means of immunoblot and immunofluorescence techniques, while reacting only weakly with R quintana. CONCLUSION: Rochalimaea henselae, recently recognized to cause persistent fever and bacteremia in immunocompetent and immunocompromised persons, also causes bacillary angiomatosis and parenchymal bacillary peliosis.

Acquired Immunodeficiency Syndrome↗
PubMed1990

A newly recognized fastidious gram-negative pathogen as a cause of fever and bacteremia.

BACKGROUND: We identified a motile, curved, gram-negative bacillus as the cause of persistent fever and bacteremia in two patients with symptomatic human immunodeficiency virus infection. The same organism was subsequently recovered from a bone marrow-transplant recipient with septicemia and from two immunocompetent persons with week-long febrile illnesses. All the patients recovered after antimicrobial therapy. METHODS AND RESULTS: Primary cultures of blood processed by centrifugation after blood-cell lysis yielded adherent, white, iridescent, morphologically heterogeneous colonies in 5 to 15 days. Subcultures grew in four days on chocolate, charcoal-yeast extract, or blood agar. The organisms stained weakly with safranin and were not acid-fast. Fluorescent-antibody tests for legionella and francisella were negative. Biochemical reactivity was minimal and difficult to ascertain. Agar-dilution testing revealed in vitro susceptibility to most antimicrobial agents tested. The cellular fatty acid composition of the isolates was similar, resembling that of Rochalimaea quintana or brucella species, but not Helicobacter pylori or species of campylobacter or legionella. As resolved by gel electrophoresis, cell-membrane preparations of all isolates contained similar proteins, with patterns that differed from that of R. quintana. Patterns of digestion of DNA from all isolates by EcoRV restriction endonuclease were virtually identical and also differed from that of R. quintana. On immunodiffusion, serum from one convalescent patient produced a line of identity with sonicates of all five isolates. CONCLUSIONS: This pathogen may have been unidentified until now because of its slow growth, broad susceptibility to antimicrobial agents, and possible requirement of blood-cell lysis for recovery in culture. It should be sought as a cause of unexplained fever, especially in persons with defective cell-mediated immunity.

Adult↗
PubMed1990

A rat model of prolonged pulmonary infection due to nontypable Haemophilus influenzae.

Pulmonary colonization and infection with nontypable (unencapsulated) Haemophilus influenzae (NTHI) occurs commonly in the setting of chronic lung diseases. Because the study of NTHI pulmonary infection in animal models has been limited by the rapid clearance of organisms, a model of persistent pulmonary infection was developed. Groups of rats were inoculated by transtracheal instillation of viable NTHI suspended in broth or semisolid agar. Some rats had received hexamethylphosphoramide (HMP) in drinking water before inoculation to cause respiratory epithelial mucosal damage. Groups of animals were sacrificed serially. Lungs were cultured quantitatively and their gross and microscopic anatomy examined. NTHI was recovered in small quantities from few broth-inoculated rats after the first day of infection and in none after Day 7. In contrast, NTHI was recovered from the majority of animals and in greater amounts through 2 wk after agar-borne inoculation. HMP pretreatment further enhanced recovery through 4 wk after inoculation with an agar vehicle. The pulmonary inflammatory reaction was brief in broth-inoculated rats. The longer persistence of gross and histologic changes seen in agar-infected lungs paralleled the enhanced recovery of NTHI. Abscess formation occurred at 7 to 14 days in some agar-inoculated animals. Thus pulmonary inoculation of NTHI in a viscous vehicle resulted in perpetuation of infection and inflammatory response, and previous damage to respiratory mucosal epithelium induced by HMP further enhanced such infection.

Animals↗
PubMed1990

Methicillin-resistant Staphylococcus aureus: a descriptive analysis on veterans.

Concern over complications of a potentially large outbreak of methicillin-resistant Staphylococcus aureus (MRSA) prompted intensive monitoring and establishment of effective communication lines between infection control practitioners, nurses, physicians, and microbiology personnel. From October, 1986, through September, 1987, 77 patients at the Veterans Administration Medical Center in Oklahoma City had MRSA. Charts were available for review on 63 of these patients. When those with charts available were reviewed, 41 patients had nosocomial (NC) and 22 had community-acquired (CA) MRSA. Of the 41 NC patients, 34 were infected (of which 17 died during hospitalization) and 7 colonized (3 died). Of the 22 CA patients, 15 were infected (4 died) and 7 colonized (2 died). Length of stay was NC-infected, mean 51.8 days; NC-colonized, 38.9 days; CA-infected, 14.9 days; and CA-colonized, 16.1 days. This study shows the importance of NC MRSA, especially as it relates to hospital costs and care of many extended stay patients.

Aged↗
PubMed1989

Clinical experience with HIV-infected patients at the University of Oklahoma Health Sciences Center.

Two hundred seventy-two patients infected with human immunodeficiency virus (HIV) have received care from the members of the adult infectious disease section at the University of Oklahoma Health Sciences Center. The majority of these patients met the diagnostic criteria for acquired immunodeficiency syndrome. This group of patients was characterized by relatively few parenteral drug abusers, a high incidence of disseminated histoplasmosis, and an unexpectedly low frequency of toxoplasmosis. The prevalence of risk behaviors and endemic disease may be responsible for these particular case distributions.

Acquired Immunodeficiency Syndrome↗
PubMed1989

Length of hospital stay in surgical service patients with nosocomial Hemophilus influenzae infections.

The length of hospitalization was characterized for 24 surgical service patients with nosocomial respiratory tract infections associated with Hemophilus influenzae. The mean number of days were: admission to surgery 8.22; surgery to culture of the nosocomial pathogen 7.00; admission to culture 16.71; admission to discharge 38.75; surgery to discharge 25.48; and culture to discharge 21.42. The length of hospital stay was prolonged for those patients with nosocomial respiratory tract infections related to H influenzae.

Cross Infection↗
PubMed1987

Serum bactericidal testing with quality control organisms.

Measurements of serum bacteriostatic and bactericidal titers were compared using common quality control organisms. Oxacillin or vancomycin was added to normal sera for duplicate testing against Staphylococcus aureus ATCC 25923 while gentamicin or ampicillin was added for duplicate testing against Escherichia coli ATCC 25922. Recommendations of acceptable ranges are presented in the text. Establishment of acceptable ranges for serum bactericidal assay results could improve accuracy, allow comparisons of data from different studies and help reduce intralaboratory variations.

Anti-Bacterial Agents↗
PubMed1984

Group B streptococcal arthritis in adults.

Group B streptococcal arthritis in adults is uncommon. This report describes seven cases seen at these institutions over the past five years and reviews the previous 17 documented cases. Of seven adults, three were diabetics, three had prosthetic hips, and one had undergone splenectomy. Six had undergone no prior dental, genitourinary, or gastrointestinal procedures. The most common clinical presentation was fever and acute joint pain. Five patients had monoarticular arthritis; two had multiple joint involvement. Underlying joint abnormalities included osteoarthritis (two), prosthetic hip (three), and neuropathic joint (one). Bacteremia was documented in three and suspected in the remaining four patients, often without a primary source. Therapy included parenteral antibiotics, usually penicillin G, and drainage of the involved joint. Two of three patients with prosthetic implants required Girdlestone procedures; the third was apparently cured. The three diabetic patients died, one with resolution of group B streptococcal arthritis. The seventh patient was cured. Group B streptococcal arthritis is a serious infection in adults with diabetes and late prosthetic hip infections.

Adolescent↗
PubMedDate not supplied

Bacteremic disease due to Haemophilus influenzae capsular type f in adults: report of five cases and review.

Five cases of bacteremic infections due to Haemophilus influenzae type f in adults are described, and previous reports of type f disease in nonpediatric patients are reviewed. Respiratory tract infections were most common in our series (two cases of pneumonia, one of epiglottitis, and one of nosocomial septicemia probably resulting from aspiration pneumonitis). All of these patients had factors predisposing them to respiratory tract infections, e.g., neurologic disease, congestive heart failure, or cigarette smoking. A fifth patient, who was bacteremic without an apparent primary focus, had dysgammaglobulinemia. Six episodes of bacteremia occurred in five patients; 11 of 13 cultures of blood obtained before parenteral antibiotic therapy were positive. All isolates were biotype I and susceptible to ampicillin. Antibiotic therapy was curative in cases of proved respiratory tract infection but failed in the setting of nosocomial septicemia, perhaps because of delayed initiation. The brevity of antibiotic treatment of the cryptogenic bacteremia permitted infection of a prosthetic vascular graft and recurrent bacteremia. Graft removal and repeated antibiotic therapy were curative.

Adult↗