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D K Henderson

Publications and source records attributed to D K Henderson.

70 records · Page 4Linked to original sources
PubMed1982

Long-lasting, specific immunologic unresponsiveness associated with cryptococcal meningitis.

A sensitive radioimmunoassay and an antibody class-specific enzyme-linked immunosorbent assay were used to determine whether patients cured of cryptococcosis responded normally to immunization with cryptococcal capsular polysaccharide (CPS) and type III pneumococcal polysaccharide. 10 normal volunteers and 8 patients who had been cured of cryptococcal meningitis and who had been cured of cryptococcal meningitis and who had no serious underlying diseases were immunized with both antigens. Geometric mean titers to CPS measured by radioimmunoassay were 1:1 in both groups before vaccination, but were 1:3 in patients and 1:119 in controls following immunization (P less than 0.01, Student's t test). Analysis of the class-specific response to immunization with CPS found little anti-CPS IgG or IgA. Geometric mean postvaccination IgM titers were 1:31 in patients and 1:238 in controls (P less than 0.01). Responses to immunization with type III pneumococcal polysaccharide were similar in patients and controls, with IgA, IgM, and IgG mean titers of 1:1129, 1:369, and 1:158 in patients and 1:1504, 1:1039, and 1:163 in controls (P greater than 0.2 for each antibody class). Cured cryptococcal meningitis is often associated with prolonged specific immunologic unresponsiveness.

Adolescent↗
PubMed1982

Comparative ocular pathogenicity of Cryptococcus neoformans, Candida glabrata, and Aspergillus fumigatus in the rabbit.

In a previous study, 88% of rabbits with disseminated infection caused by Candida albicans developed ophthalmoscopically visible, hematogenous endophthalmitis (chorioretinitis) over a 2 week period. To determine the incidence of this ocular complication in disseminated infection caused by Cryptococcus neoformans, Candida glabrata, and Aspergillus fumigatus compared with that caused by C. albicans, the first three species of fungi were injected intravenously (between 10(5) and 10(9) organisms per animal) into 36 New Zealand white rabbits. No chorioretinal lesions were seen by indirect ophthalmoscopy over a 2 week period. C. glabrata and A. fumigatus were not cultured from chorioretinas despite positive cultures from brains and kidneys at 1 and 2 weeks. In contrast, C. neoformans was cultured from 12 of 18 chorioretinas. (mean Log10 3.45 colony forming units/gm of tissue) as well as from the brains and kidneys. The less intense inflammatory cell response to C. neoformans compared with that 10 C. albicans seen on histopathologic examination most likely explains the nondetectability of the cryptococcal chorioretinitis by indirect ophthalmoscopy. These data suggest that C. glabrata. A. fumigatus, and possibly C. neoformans have less ocular pathogenicity than C. albicans in rabbits and correlate with the small number of documented human cases of ophthalmoscopically visible hematogenous endophthalmitis caused by fungi other than C. albicans.

Animals↗
PubMed1981

Hematogenous candida endophthalmitis in patients receiving parenteral hyperalimentation fluids.

To determine the incidence of hematogenous candida endophthalmitis in seriously ill patients given parenteral hyperalimentation fluids, 131 hyperalimented postoperative patients were prospectively evaluated. All patients were screened weekly for the development of chorioretinal lesions, blood cultures positive for Candida albicans, and signs and symptoms of candida infection. Thirteen (9.9%) of 131 patients developed chorioretinal lesions compatible with hematogenous candida endophthalmitis. Seven of the 13 patients with eye lesions had blood cultures positive for yeast, whereas only two of 118 without eye lesions had blood cultures positive for yeast (P less than 0.0005). Thus, the occurrence of eye lesions consistent with hematogenous candida endophthalmitis correlated with positive blood cultures for yeast and strongly suggested invasive candidiasis.

Amphotericin B↗
PubMed1980

Combined effect of amphotericin B and rifampin on Candida species.

Synergism with the combination of rifampin and amphotericin B in vitro has been demonstrated with a limited number of Candida strains. To extend these studies (particularly at clinically achievable levels of rifampin), we evaluated the in vitro combined activity of serial twofold dilutions of amphotericin B (0.1 to 6.0 microgram/ml) against 11 concentrations of rifampin (0.2 to 200 microgram/ml) for 40 strains of Candida: 20 Candida albicans, 7 Candida parapsilosis, 8 Candida tropicalis, 2 Candida stellatoidea, 2 Candida guilliermondii, and 1 Candida krusei by using a modified checkerboard microtitration technique. An additive or synergistic effect was seen for 45% of strains with 6.25 microgram of rifampin per ml added to amphotericin B. Whereas the minimal inhibitory concentration to amphotericin B alone was 0.4 microgram/ml or less for 50% of the strains, the percentage increased to 90 with the addition of 6.25 microgram of rifampin per ml. A similar effect was seen with killing: 25% of the strains were killed by 0.4 microgram or less of amphotericin B alone per ml, and 75% of the strains were killed with the addition of 6.25 microgram of rifampin per ml. In vivo studies are needed for confirmation of the usefulness of combined amphotericin B and rifampin therapy.

Amphotericin B↗
PubMed1980

Effect of immunosuppression on the development of experimental hematogenous Candida endophthalmitis.

The induction of neutropenia and immunosuppression by the administration of nitrogen mustard (HN2) decreased the frequency and altered the morphology of clinically detectable hematogenous Candida endophthalmitis in the rabbit model of disseminated candidiasis. Whereas 95% of eyes in rabbits infected with Candida albicans without pretreatment with HN2 developed typical lesions of hematogenous Candida endophthalmitis, only 6.2% of eyes in rabbits that had been given 3.0 mg of HN2 per kg developed clinically detectable endophthalmitis. Lesions that developed in the severely immunocompromised and neutropenic rabbits were small and atypical in appearance. From these data, we conclude that ophthalmoscopic examination may not be a sensitive diagnostic modality for disseminated candidiasis in severely immunocompromised, neutropenic patients.

Agranulocytosis↗
PubMed1979

Experimental hematogenous Candida endophthalmitis: diagnostic approaches.

Anterior chamber aspiration and vitreous aspiration were evaluated as diagnostic procedures for establishing a specific microbiological diagnosis in the rabbit model of hematogenous Candida endophthalmitis. Vitreous aspiration was the most successful procedure, confirming the diagnosis of hematogenous Candida endophthalmitis in 62% of eyes with documented intraocular infection. When animals with only the most severe clinical endophthalmitis were considered, vitreous aspiration confirmed the diagnosis in 89% of eyes evaluated. Vitreous aspiration correlated well with the extent of clinical endophthalmitis, as well as with postmortem, whole-vitreous cultures. Gram staining of the aspirate was additive to culture results in confirming the diagnosis. Anterior chamber aspiration was positive in only 1 of 58 eyes evaluated (1.7%). Additionally, muscle biospy was evaluated in this study as a tool for establishing a microbiological diagnosis in the rabbit model of disseminated candidiasis. Only 2 of 131 biospy specimens contained detectable Candida. Although vitreous aspiration may be associated with ocular complications, in certain clinical settings this procedure may be valuable in establishing the definitive microbiological diagnosis of hematogenous Candida endophthalmitis.

Animals↗
PubMed1977

Comparative susceptibility of anaerobic bacteria to ticarcillin, cefoxitin, metronidazole, and related antimicrobial agents.

The in vitro antimicrobial activity of two newer agents, ticarcillin and cefoxitin, against 204 recent clinical isolates of anaerobic bacteria was determined by an agar dilution technique, and compared to their related compounds carbenicillin, cephalothin, and penicillin, as well as metronidazole, clindamycin, and chloramphenicol. Ticarcillin was similar to carbenicillin, and cefoxitin was more active than cephalothin. At readily achievable blood concentrations of each antimicrobial agent, ticarcillin was slightly less active than clindamycin against Bacteroides fragilis. Cefoxitin was superior to cephalothin and penicillin against B. fragilis. Penicillin remained highly active against all obligate anaerobes other than B. fragilis. Metronidazole, while highly effective against B. fragilis and Clostridium perfringens, was only intermediately effective against anaerobic gram-positive cocci and relatively inactive against nonsporulating anaerobic gram-positive bacilli. Further evaluation of the clinical efficacy of ticarcillin, carbenicillin, and cefoxitin against anaerobic infections is indicated.

Anaerobiosis↗
PubMedDate not supplied

Use of precautions by nurse-midwives to prevent occupational infections with HIV and other blood-borne diseases.

A questionnaire was designed with these objectives: (1) to determine the frequency and type of adverse exposures experienced by certified nurse-midwives (CNMs); (2) to determine the extent to which CNMs used recommended precautions to prevent such incidents; and (3) to identify the sources used for obtaining information on AIDS. The questionnaire was mailed to all CNMs with the exception of associate and student members of the American College of Midwives. A response rate of 1,784/2,963 (60.2%) was obtained. These midwives reported frequent exposures to blood and body fluids. Sixty-five percent reported being soaked to the skin with blood or amniotic fluid; 50.7% had face-splashes with blood or amniotic fluid; and 24.0% experienced one or more needlestick(s). Only 55.1% reported using Universal Precautions (UP). Interference with the midwife-client relationship was identified most frequently as the reason for not using UP. Strategies need to be developed for midwives that will increase the use of UP and minimize the frequency of adverse exposures, while maintaining a caring midwife-client relationship.

Acquired Immunodeficiency Syndrome↗
PubMedDate not supplied

HIV postexposure prophylaxis in the 21st century.

The administration of postexposure prophylaxis has become the standard of care for occupational exposures to HIV. We have learned a great deal about the safety and potential efficacy of these agents, as well as the optimal management of health-care workers occupationally exposed to HIV. This article describes the current state of knowledge in this field, identifies substantive questions to be answered, and summarizes basic principles of postexposure management.

Animals↗