Biomedical subjects

C J Perkins

Publications and source records attributed to C J Perkins.

5 recordsLinked to original sources

PubMed2001

Fluid-attenuated inversion recovery and diffusion- and perfusion-weighted MRI abnormalities in 117 consecutive patients with stroke symptoms.

BACKGROUND AND PURPOSE: Diffusion-weighted MRI (DWI) is highly sensitive to early cerebral ischemia, but its dependence on lesion location, acuity, and etiology remains unknown. Furthermore, although a marked perfusion-weighted MRI (PWI)-DWI mismatch may exist in a subset of acute strokes, the frequency and distribution of these mismatches have never been methodically characterized in an unselected population. To address these 2 issues, we evaluated echo-planar imaging in 117 consecutive patients with signs and symptoms of acute stroke. METHODS: Clinical diagnoses were determined by chart review. Fluid-attenuated inversion recovery (FLAIR), DWI, and PWI sequences were scored for lesion acuity, neuroanatomy, and vascular territory. Lesion and PWI-DWI mismatch volumes were determined by image analysis. RESULTS: DWI was more sensitive than was FLAIR for the detection of stroke for all subtypes in all anatomic distributions and at all tested time intervals. Although DWI exhibited its greatest benefit over FLAIR during the first 6 hours, it was still superior to FLAIR even after 24 hours. PWI abnormalities were detected in 49% of patients with DWI abnormalities. In the majority of these cases, the PWI-DWI mismatch was substantially larger than the DWI lesion itself. Both the largest DWI lesion volumes and the largest mismatch volumes occurred in patients with carotid disease. CONCLUSIONS: DWI nearly doubles the likelihood of detecting acute ischemic stroke lesions compared with FLAIR for all etiologies and in all anatomic locations. In the hyperacute period (0 to 6 hours), DWI more than triples the likelihood of acute-stroke detection over FLAIR. PWI reveals a measurable mismatch compared with DWI nearly 50% of the time; and in more than half of these patients, the ratio of the volume of the PWI lesion to the DWI lesion is several times larger than the core ischemic lesion itself. In the final analysis, approximately one fourth of all stroke patients present with a large volume of potentially salvageable tissue at risk for infarction.

Acute Disease↗

PubMed1996

Causes of fever in patients infected with human immunodeficiency virus who were admitted to Boston City Hospital.

We prospectively studied causes of fever in patients with human immunodeficiency virus (HIV) infection that required admission to a municipal hospital. A total of 168 HIV-infected persons were admitted for 220 episodes of fever: 72% were male, 80% were nonwhite, 65% reported prior injection drug use, and 74% had a baseline CD4 lymphocyte count of < 200/mm3. Bacterial infections, principally pneumonia, accounted for > 60% of the episodes; Streptococcus pneumoniae and Staphylococcus aureus were most commonly isolated. Pneumocystis carinii pneumonia (PCP) and disseminated infection with Mycobacterium avium complex (MAC) comprised 53% of the remaining sources of fever. In comparison with episodes of fever due to nonbacterial causes, those associated with common bacterial infections were significantly more likely to involve patients with a history of injection drug use (P = .02), higher admission leukocyte count (P < .004), shorter duration of fever (P = .003), shorter hospital stays (P = .0001), and a CD4 count of > 100/mm3 (P = .002). We conclude that bacterial infection, especially pneumonia, is a common cause of fever in HIV-infected patients admitted to our hospital. Patients with bacterial infections are more likely to report a history of injection drug use and have CD4 counts of > 100/mm3, shorter duration of fever, decreased length of hospitalization, and lower mortality than patients with fever due to PCP, disseminated MAC infection, or other causes.

AIDS-Related Opportunistic Infections↗

PubMed1990

Once-daily administration of 2',3'-dideoxyinosine (ddI) in patients with the acquired immunodeficiency syndrome or AIDS-related complex. Results of a Phase I trial.

We conducted a Phase I open-label trial of 2',3'-dideoxyinosine (ddI) for the treatment of the acquired immunodeficiency syndrome (AIDS) and severe AIDS-related complex. A single daily dose of ddI was administered orally to 34 patients (17 with AIDS and 17 with AIDS-related complex) for a median of 12 weeks (range, 2 to 56). We studied six dose levels from 1.6 to 30.4 mg per kilogram of body weight per day. Of the 17 patients previously treated with zidovudine, 13 had had hematologic side effects. The maximal tolerated dose of oral ddI was estimated to be 20.4 mg per kilogram per day. Pancreatitis and peripheral neuropathy were the major dose-limiting toxic effects. Other toxic effects included elevations in hepatic transaminase levels, abnormalities in cardiac conduction, rash, and asymptomatic elevations in serum urate levels and the creatine kinase fraction from skeletal muscle. Treatment with ddI was associated with an increase in the mean number of CD4 lymphocytes from 125 per cubic millimeter at base line to 182 per cubic millimeter after 10 weeks (P = 0.005). There were also increases after 12 weeks in the mean total lymphocyte count (from 0.8 to 1.2 x 10(9) per liter) and the mean hemoglobin level (from 12.9 to 14.1 g per deciliter) (both P less than 0.01). The amount of human immunodeficiency virus p24 antigen decreased by more than 50 percent in 14 of 19 patients with detectable antigen. No differences in response were observed between patients previously treated with zidovudine and those never treated with the drug. We conclude that ddI has antiretroviral activity in patients with AIDS or AIDS-related complex and that the toxicity of ddI differs from that of zidovudine. However, controlled trials are necessary to evaluate the efficacy of ddI.

AIDS-Related Complex↗

PubMed1977

Insulin aggravated postural hypotension.

In a 76-year-old diabetic with symptomatic postural hypotension during the mornings, this was greatly improved by changing his time of insulin administration from 7.30 a.m. to 11.30 a.m.

Aged↗

PubMedDate not supplied

Treatment of AIDS and AIDS-related complex with 2',3'-dideoxyinosine given once daily.

In a phase I dosage-finding trial, 2',3'-dideoxyinosine (didanosine; ddI) was administered once daily to 36 patients with AIDS or AIDS-related complex for up to 65 weeks (mean, 32.1 weeks) at six dosage levels. Thirteen of 18 patients previously treated with zidovudine had developed hematologic intolerance. The maximal tolerated dosage of ddI was 12 mg/(kg.d); dose-limiting toxicities were pancreatitis and peripheral neuropathy. Other toxicities included elevation in hepatic transaminase levels, rash, cardiac conduction abnormality, and asymptomatic hyperuricemia. Eighty-six percent of patients who completed 6 weeks of treatment showed improvement in constitutional symptoms and significant weight gain. In patients treated with ddI, the mean number of CD4+ lymphocytes increased from 124/mm3 at baseline to 199/mm3 at 24 weeks (P = .0027) and the mean leukocyte count, total lymphocyte count, and hemoglobin level showed increases (all P less than .01) after 12 weeks. Serum levels of viral p24 antigen decreased greater than or equal to 50% in 14 of 19 assessable patients. No differences between the responses of patients previously treated with zidovudine and those of zidovudine-naive patients were observed. These results indicate that ddI has significant antiretroviral activity in vivo and a toxicity profile different from that of zidovudine.

AIDS-Related Complex↗