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K Sepkowitz

Publications and source records attributed to K Sepkowitz.

11 recordsLinked to original sources
PubMed1995

Multidrug-resistant tuberculosis in patients without HIV infection.

BACKGROUND: Investigations of outbreaks of multidrug-resistant tuberculosis have found low rates of treatment response and very high mortality, and they have mainly involved patients with advanced human immunodeficiency virus (HIV) infection. For patients without HIV infection, one study reported an overall rate of response to treatment of 56 percent, and the mortality from tuberculosis was 22 percent. We investigated treatment response and mortality rates in 26 HIV-negative patients in New York with multidrug-resistant tuberculosis. METHODS: We obtained detailed data from seven teaching hospitals in New York City on patients with multidrug-resistant tuberculosis--defined as tuberculosis resistant at least to isoniazid and rifampin--who were HIV-negative on serologic testing. Lengths of times from diagnosis to the initiation of appropriate therapy and from the initiation of appropriate therapy to conversion to negative cultures were assessed. Therapeutic responses were evaluated by both microbiologic and clinical criteria. RESULTS: Between March 1991 and September 1994, 26 HIV-negative patients were identified and treated. Of the 25 patients for whom adequate data were available for analysis, 24 (96 percent) had clinical responses; all 17 patients for whom data on microbiologic response were available had such a response. The median times from diagnosis to the initiation of appropriate therapy and from the initiation of therapy to culture conversion were 44 days (range, 0 to 181) and 69 days (range, 2 to 705), respectively. Side effects requiring the discontinuation of medication occurred in 4 of 23 patients (17 percent) who were treated with second-line antituberculosis medications. The median follow-up for the 23 patients who responded and who received appropriate therapy was 91 weeks (range, 41 to 225). CONCLUSIONS: In this report from New York City, HIV-negative patients with multidrug-resistant tuberculosis, contrary to previous reports, responded well to appropriate chemotherapy, both clinically and microbiologically.

Adult↗
PubMed1995

Dramatic decrease in tuberculin skin test conversion rate among employees at a hospital in New York City.

BACKGROUND: The Centers for Disease Control and Prevention recently issued updated guidelines for preventing the transmission of tuberculosis in health care facilities. Many recommendations, including the use of high-efficiency particulate air filter respirators, are expensive to implement and of unproven efficacy. We therefore reviewed the tuberculin skin test conversion rate among our employees from 1991 to 1993, before introduction of high-efficiency particulate air filter respirators. During this period, several other improvements in tuberculosis control were implemented. METHODS: Employee tuberculin test conversion rates were reviewed by 6-month interval from 1991 to 1993. RESULTS: Throughout the study period, several tuberculosis control measures were implemented, including early isolation of patients with suspected cases of tuberculosis in rooms with negative-pressure ventilation, placement of germicidal UV light fixtures into patient rooms and common areas, and use of Technol shields (Technol, Inc., Fort Worth, Texas) (1991), particulate respirators (1992), and dust-mist-fume respirators (1993). With these improvements, the conversion rate among employees fell from 20.7% in the first 6 months of 1991 to 5.8% in the latter half of 1993. CONCLUSIONS: The rate of skin test conversion among our employees decreased before introduction of high-efficiency particulate air filter respirators. This suggests that nosocomial spread of tuberculosis can be decreased by means of previously established, less costly methods.

Cross Infection↗
PubMed1993

DNA amplification in experimental pneumocystosis: characterization of serum Pneumocystis carinii DNA and potential P. carinii carrier states.

DNA amplification has identified P. carinii DNA in diverse biologic specimens, including the serum of patients with P. carinii pneumonia. To further examine the relationship between P. carinii DNA in serum and P. carinii infection, the corticosteroid-treated rat model of pneumocystosis was studied. By 4 weeks of immunosuppression, P. carinii DNA was detected in rat lungs and by 6 weeks, in their serum. P. carinii DNA persisted in lung tissue as long as 5 months after the withdrawal of steroids. Serum DNA disappeared 2 weeks after steroids were withdrawn. Nonimmunocompromised, sentinel rats housed near immunocompromised, P. carinii-infected rats also were studied. Within 6 weeks, P. carinii DNA became detectable in lung and by 8 weeks, in serum. P. carinii DNA disappeared rapidly from lungs and sera after sentinel rats were isolated away from corticosteroid-treated rats. These findings support the contagious transmission of P. carinii and suggest facile development of P. carinii carrier states.

Animals↗
PubMed1992

Application of DNA amplification to pneumocystosis: presence of serum Pneumocystis carinii DNA during human and experimentally induced Pneumocystis carinii pneumonia.

Pneumocystis carinii pneumonia is a leading cause of morbidity and mortality in patients with the acquired immunodeficiency syndrome (AIDS). Much remains unknown about the basic biology of P. carinii and studies of this infection have been hampered by the lack of cultivation methods. We developed a sensitive and specific assay for P. carinii by utilizing DNA amplification of the P. carinii dihydrofolate reductase (DHFR) gene. By this method, P. carinii DNA was detected in the lungs of rats with experimentally induced P. carinii pneumonia 2 wk before the onset of histopathological changes. DNA amplification analysis of serum demonstrated that by 10 wk of corticosteroid treatment, 12 of 12 (100%) infected rats had circulating DHFR DNA. P. carinii DHFR DNA also was detected in the serum of patients with AIDS and active P. carinii pneumonia (12 of 14 sera collected prospectively). Patients with advanced AIDS but without a history of P. carinii pneumonia were negative by this assay (0 of 6 sera examined). Serum polymerase chain reaction may facilitate investigations into the natural history and epidemiology of P. carinii infection, provide insight into the pathogenesis of parasite dissemination, and offer a useful, noninvasive diagnostic test for the detection of human pneumocystosis.

Acquired Immunodeficiency Syndrome↗
PubMed1981

A study of some mitochondrial and peroxisomal enzymes in human colonic adenocarcinoma.

Three mitochondrial enzymes, cytochrome oxidase, succinate dehydrogenase, and monoamine oxidase, and two peroxisomal enzymes, catalase and urate oxidase, were measured spectrophotometrically in the postnuclear supernatant prepared from homogenates of normal mucosa and carcinoma of the human colon. The specific activities, in both normal mucosa and carcinoma, varied from patient to patient. However, the difference in these activities between normal mucosa and carcinoma was consistent when patients were compared. The activities of cytochrome oxidase, succinate dehydrogenase, monoamine oxidase, and catalase were greater in normal mucosa than in carcinoma. In contrast, urate oxidase activity increased in carcinoma as compared with normal mucosa. Furthermore, cytochrome oxidase and succinate dehydrogenase decreased proportionally in carcinoma, supporting the concept that the mitochondrial respiration in normal tissue and carcinoma is quantitatively but no qualitatively changed. However, the decrease in monoamine oxidase activity in carcinoma was greater than that observed with other mitochondrial enzyme activities and was irregular. This suggests that a qualitative mitochondrial change may occur in carcinoma. In particular, the ratio between outer membrane enzyme activity and respiratory enzyme activity may be altered.

Adenocarcinoma↗
PubMedDate not supplied

Detection of Pneumocystis carinii in serum of AIDS patients with Pneumocystis pneumonia by the polymerase chain reaction.

Amplification of DNA by the polymerase chain reaction (PCR) offers a highly sensitive and specific method for detecting DNA sequences in biological samples. We applied this technology to develop an assay for the P. carinii dihydrofolate reductase (DHFR) gene. This assay was found to be sensitive enough to detect as little as 1 organism-'equivalent' of DHFR DNA. In rats with experimentally-induced P. carinii pneumonia, DHFR DNA amplification demonstrated the presence of pulmonary P. carinii 2 wk prior to the onset of histopathological changes. When rat serum was analyzed by PCR, serum P. carinii DNA was found in 5 of 14 experimental rats. Finally, P. carinii DNA was detected in the serum of 7 of 18 patients (39%) with AIDS and active P. carinii pneumonia. These results suggest that circulating serum P. carinii DNA can be detected frequently in the course of pulmonary infection and may represent a blood-borne phase of infection. The PCR detection of P. carinii DNA provides a useful tool to study the natural history of P. carinii infection and may offer a non-invasive diagnostic procedure in some patients with P. carinii pneumonia.

Acquired Immunodeficiency Syndrome↗