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D L Pitrak

Publications and source records attributed to D L Pitrak.

24 records · Page 2Linked to original sources

Depressed neutrophil superoxide production in human immunodeficiency virus infection.

Neutrophil (PMNL) superoxide (O2-) production was evaluated in 71 patients with human immunodeficiency virus (HIV) infection at different stages of disease. In vitro O2- production was significantly depressed for PMNL isolated from HIV-positive patients compared with control PMNL at rest and after stimulation. The degree of impairment of O2- production was more pronounced for patients with lower absolute CD4+ lymphocyte counts. Antiretroviral therapy with zidovudine was also associated with impaired O2- production, but this may reflect a longer duration of disease for treated patients. Zidovudine had no direct inhibitory effect on O2- production by control PMNL in vitro, and serial measurements of O2- production by PMNL from patients before and after initiation of zidovudine did not demonstrate an in vivo inhibitory effect. Impaired PMNL oxidative metabolism in HIV infection may contribute to the increased risk of serious bacterial infections, certain opportunistic infections, and perhaps the pathogenesis of HIV infection itself.

Adult↗

Frequency of cells positive for HIV-1 p24 antigen assessed by flow cytometry.

OBJECTIVE: Markers of HIV disease progression such as soluble p24 antigen detection and CD4 lymphocyte depletion are most useful in the later stages of HIV disease and are relatively insensitive as therapeutic monitors. Flow cytometric detection of HIV-1 replication in CD4 lymphocytes was evaluated for use as a marker in predicting disease progression earlier in the course of HIV disease. DESIGN: To determine whether the number of HIV-1-infected CD4 cells, as measured by p24 antigen detection, can be correlated with disease progression, we used flow cytometry to detect intracellular HIV-1 p24 in CD4 lymphocytes from HIV-1-seropositive subjects at all stages of HIV disease. METHODS: Mononuclear cells from HIV-1-seropositive subjects and uninfected control subjects were permeabilized and stained with anti-HIV-1 p24 monoclonal antibodies. The cells were then stained with a fluorescein isothiocyanate-conjugated goat antimurine immunoglobulin G followed by a phycoerythrin-conjugated monoclonal anti-CD4 antibody. The percentage of p24-positive CD4 lymphocytes was compared with absolute CD4 counts, soluble p24 detection and Walter Reed classification. RESULTS: CD4 lymphocyte absolute counts and the percentage of CD4 lymphocytes declined as the Walter Reed classification indicated disease progression. The mean percentage of p24 antigen-positive CD4 lymphocytes increased with disease progression. Only 30% of Walter Reed stage 6 subjects were soluble p24 antigen-positive, whereas 68% were cellular p24 antigen-positive. CONCLUSION: The percentage of p24 antigen-positive CD4 lymphocytes increased as HIV disease progressed. Flow cytometric quantitation of p24 antigen-positive CD4 cells is a useful method of monitoring in vivo HIV replication and disease progression.

Biomarkers↗

Management of cytomegalovirus infection in patients with acquired immunodeficiency syndrome.

The clinical manifestations of cytomegalovirus (CMV) infection in persons with AIDS are described, and recent advances in the management of these syndromes with antiviral agents are reviewed. CMV infection is the most common serious opportunistic viral infection in AIDS patients. Clinical manifestations include chorioretinitis, gastroenteritis, hepatitis, pneumonia, CNS infection, adrenalitis, and a wasting syndrome. The diagnosis of CMV infection requires laboratory demonstration of a serologic response to the virus, detection of viral components or products, or isolation of the virus. Ganciclovir is an acyclic nucleoside analogue marketed for the treatment of CMV-related retinitis in immunocompromised hosts. After i.v. ganciclovir induction therapy, more than 80% of patients show improvement or stabilization of retinitis. Relapse is common in AIDS patients, however, and low-dose i.v. maintenance therapy is recommended. The most serious dose-limiting effect is neutropenia. Intravitreal injection of ganciclovir has been well tolerated and efficacious. Ganciclovir has shown some efficacy in the treatment of other life-threatening CMV infections, especially gastroenteritis, but data are limited. Ganciclovir-resistant strains have been reported. Foscarnet, a pyrophosphate analogue with activity against both human CMV and human immunodeficiency virus, is undergoing clinical trials. Foscarnet has shown promise in the therapy of CMV-related retinitis, but results for other CMV infections are disappointing. Nephrotoxicity is the major dose-limiting effect. AIDS patients with sight-threatening and rapidly progressive CMV-related retinitis should be treated with ganciclovir. Foscarnet may offer an alternative when it becomes available. More must be learned about the efficacy of these drugs in the treatment of CMV infection in patients with AIDS.

Acquired Immunodeficiency Syndrome↗

Bacteremic cellulitis caused by non-serogroup O1 Vibrio cholerae acquired in a freshwater inland lake.

The number of reported cases of infections with non-serogroup O1 Vibrio cholerae in the United States has increased recently. These cases have almost invariably been associated with travel, seawater exposure, or the ingestion of shellfish. We report a case of bacteremic cellulitis caused by non-O1 V. cholerae that was acquired in a freshwater inland lake in northern Illinois. The organism is more widely distributed than generally appreciated, and the potential for infection in patients without the usual risk factors exists.

Adult↗

Phialophora richardsiae infection in humans.

Phialophora richardsiae infection in humans is rare. The first human isolate was recovered from a patient with a phaeomycotic cyst in 1968. Since 1975 seven other cases have appeared in the world literature, and an additional case is reported here. The mean age of these nine patients was 61.4 years. Two patients had diabetes mellitus, one had diabetes mellitus and disseminated adrenocortical carcinoma, and one had a myeloproliferative disorder. The mode of acquisition was presumed to be inoculation with contaminated plant material, but a history consistent with an inoculation injury was obtained in only four patients and a retained splinter was found in the lesion of only one patient. Infection with P. richardsiae was not associated with systemic symptoms or signs. Six patients presented with a single subcutaneous cystic granulomatous lesion. One patient had chronic dacryocystitis. More extensive or invasive disease occurred in two patients, both with an ultimately fatal underlying neoplastic process. A specific etiologic diagnosis was made by culture of purulent material obtained by excisional biopsy in six patients, incision and drainage in one patient, aspiration in one, and spontaneous drainage in one. Subcutaneous nodules were cured with surgical excision. There is insufficient information concerning antifungal therapy to recommend its use.

Female↗