A comparison of HIV-positive patients with and without infective endocarditis: an echocardiographic study--the Emory Endocarditis Group experience

OBJECTIVE: To determine the clinical features in HIV-positive patients with and without infective endocarditis (IE). PATIENTS AND METHODS: All bacteremic, HIV-positive patients with suspected IE admitted over a four-year period who underwent either transesophageal echocardiography (TEE) or transthoracic echocardiography (TTE) were retrospectively reviewed with regard to clinical, laboratory, and demographic characteristics. RESULTS: Ten (11.5%) of 87 HIV-positive patients had a clinical diagnosis of IE based on the Duke Criteria. The mean age of patients with IE was 37.8 years and without IE 39.9 years (P = NS). Both patient groups were similar with respect to gender, race, IVDA, renal failure requiring hemodialysis, history of predisposing heart disease, origin of infection, and causative organism of infection. The mean CD4 count (cells/microL) was 200.7 in patients with IE and 95.9 in patients without IE (P = NS). Of 10 HIV-positive patients with IE, seven had left-sided heart involvement, two had complications related to IE, three required cardiothoracic surgery, and three died. CONCLUSIONS: There were no differences found with regard to the clinical characteristics of HIV-positive patients with and without IE. No correlation could be drawn between mortality and the degree of immunosuppression in patients from this study. The high incidence of IE (11.5%) and mortality rate (30%) in this study suggests that IE in HIV-positive patients, including non-intravenous drug abusers, represents a real concern for clinicians and their management of these patients.     

Hematogones: a multiparameter analysis of bone marrow precursor cells

Morphologically distinct lymphoid cells with homogeneous, condensed chromatin and scant cytoplasm can be observed in large numbers in the bone marrow of children with a variety of hematologic and nonhematologic disorders. In some patients, these cells may account for greater than 50% of the bone marrow cells, creating a picture that can be confused with acute lymphoblastic leukemia (ALL) or metastatic tumor. Although originally called hematogones (HGs), a variety of other names have been proposed for these unique cells. The clinical significance of expanded HGs has not been resolved, and the biologic features of these cells are incompletely described. In this study, we correlate the clinical, morphologic, cytochemical, flow cytometric, molecular, and cytogenetic properties of bone marrow samples from 12 children with substantial numbers of HGs (range 8% to 55% of bone marrow cells). Diagnoses in these patients included anemia, four; neutropenia, one; anemia and neutropenia, one; idiopathic thrombocytopenic purpura, two; retinoblastoma, two; Ewing's sarcoma, one; and germ cell tumor, one. Flow cytometric analyses of bone marrow cells demonstrated a spectrum extending from early B-cell precursors (CD10+, CD19+, TdT+, HLA-Dr+) to mature surface immunoglobulin-bearing B cells in these patients, corroborating our morphologic impression of HGs, intermediate forms, and mature lymphocytes. DNA content was normal, and no clonal abnormality was identified by either cytogenetic or immunoglobulin and T-cell receptor (TCR) gene rearrangement studies. Follow-up ranged from 3 months to 3 years. None of the patients has developed acute leukemia or bone marrow involvement by solid tumor. The possible role of HGs in immune recovery and hematopoiesis is presented.     

Does using heat with eutectic mixture of local anesthetic cream shorten analgesic onset time? A randomized,placebo-controlled trial

STUDY OBJECTIVES: We determine whether the addition of heat to topical eutectic mixture of local anesthetic (EMLA) cream shortens the onset time to effective analgesia. We hypothesized that applying EMLA cream for 20 minutes with an external heat pack would be as effective as the standard 60-minute application time. METHODS: In this prospective, double-blind study using adult volunteers, research subjects were randomized into groups undergoing either 20 minutes or 60 minutes of EMLA cream application time. Each research subject underwent randomized cream application over both hands and wrists in the following manner: EMLA cream with heat, EMLA cream without heat, placebo with heat, and placebo without heat. Research subjects then underwent a single attempt at intravenous catheterization over each of the 4 sites and scored the degree of pain using a 100-mm visual analog scale. RESULTS: Seventy-six research subjects were enrolled: 39 were randomized to the 20-minute group, and 37 were randomized to the 60-minute group. EMLA cream applied for 20 minutes with heat (adjusted mean visual analog scale score of 31.9 mm) provided statistically and clinically significantly greater analgesia compared with that seen in the placebo groups with or without heat (46.6 and 46.1 mm, respectively), with estimated differences of -14.6 (95% confidence interval [CI] -21.2 to -8.1) and -14.1 (95% CI -20.8 to -7.3), respectively. However, applying EMLA cream for 60 minutes without heat (16.6 mm) provided better analgesia compared with that seen after 20 minutes of EMLA cream with heat (31.9 mm; estimated difference of -15.4 [95% CI -25.1 to -5.6]). CONCLUSION: Applying EMLA cream for 20 minutes with heat provides intermediate analgesia for intravenous catheter placement, although 60 minutes of application time remains superior.     

Proteolytic inactivation of human factor VIII procoagulant protein by activated human protein C and its analogy with factor V

Purified human factor VIII procoagulant protein (VIII:C) was treated with purified human activated protein C (APC) and the loss of VIII:C activity correlated with proteolysis of the VIII:C polypeptides. APC proteolyzed all VIII:C polypeptides with mol wt = 92,000 or greater, but not the doublet at mol wt = 79-80,000. These results and our previous thrombin activation studies of purified VIII:C, are analogous with similar studies of factor V and form the basis for the following hypothesis: activated VIII:C consists of heavy and light chain polypeptides [mol wt = 92,000 and mol wt = 79-80,000 (or 71-72,000), respectively] which are similar in Mr to the heavy and light chains of activated factor V. Thrombin activates VIII:C and V by generating these polypeptide chains from larger precursors and APC inactivates both molecules by cleavage at a site located in the heavy chain region of activated VIII:C and V.     

Further characterization of platelet-type von Willebrand's disease in Japan

We studied four patients who showed aggregation of platelets in platelet-rich plasma at lower concentrations of ristocetin than those required for normal platelet-rich plasma and who demonstrated an increased capacity of the platelets to bind normal von Willebrand factor. The four patients were from two Japanese families. Platelets from one family aggregated spontaneously in vitro, and platelets from both families aggregated upon the addition of normal plasma and cryoprecipitate, in the absence of ristocetin or other agonists. Analysis of the multimeric composition of von Willebrand factor by sodium dodecyl sulfate-agarose gel electrophoresis revealed a decrease in large multimers or a decrease in both large and intermediate multimers in plasma, but normal multimers in platelets. 1-Deamino-[8-D- arginine]-vasopressin caused by an immediate appearance of larger multimers in plasma, followed by the rapid disappearance of these multimers from circulating plasma. Analysis of platelet membrane glycoproteins from the patients showed that there were two distinct bands in the glycoprotein I region; one migrated in a slower region and the other in a faster region than normal glycoprotein Ib. We suggest that the platelet receptor abnormality in these patients is related to this abnormality of glycoprotein Ib.     

A radiolabeled antiglobulin test for crossmatching platelet transfusions

Despite the use of HLA-matched platelets for alloimmunized recipients, transfusion failures occur. In order to reduce these failures, we investigated the use of a radiolabeled antiglobulin technique for platelet crossmatching. The principle of the test is that of an indirect Coombs test using 125I labeled goat anti-human IgG. Incompatibility is determined by calculating a radioactivity antiglobulin test (RAGT) index. Using this technique, we performed 89 crossmatches on 19 leukemic or aplastic patients who were refractory to random donor platelets and receiving varying degrees of HLA-matched platelets. Effectiveness of the transfusion was assessed from the posttransfusion corrected platelet count increment (CCI) determined at 1 and 20 hr. When the RAGT index was 1.9 or less, the mean CCI at 1 lhr was 17,570 +/- 7003/cu mm, n = 55. When the RAGT index was 2.0 or greater, the mean CCI was 4237 +/- 4100/cu mm, n = 34. At 20 hr when the RAGT index was 1.9 or less, the mean CCI was 8722 +/- 3143/cu mm, n = 33, and when the index was 2.0 or greater, the mean CCI was 571 +/- 1286/cu mm, n = 23. Using this technique, one false negative resulted. Nine positive crossmatches with good increments at 1 hr were found; at 20 hr, however, the survival of these units was zero. These data suggest that this method is a useful adjunct in the selection of platelets in the refractory patient.     

Cardiovascular Response to Acute Cold Stress in Non-Obese and Obese Healthy Adults

Background

Obesity is a global epidemic with important health care and financial implications. The cold pressor test (CPT) which is considered to be a sympathy-excitatory manoeuvre is a simple, noninvasive and validated test. The objective of this study was to assess and compare the cardiovascular response to cold pressor test in non-obese and obese healthy adults.

Methods

The study included 400 subjects, of which the study group included 200 adults who had body mass index (BMI) of more than 30 Kg/m,² and 200 non-obese adults were enrolled as controls with BMI less than 25 kg/m². The study was conducted for a period of two months. CPT was used to assess cardiac response to acute cold exposure in the present study. Baseline systolic and diastolic blood pressure recording was done using mercury sphygmomanometer during resting condition and following cold pressor test. The results were expressed as mean, standard deviation, and data were analyzed using ANOVA test. P < 0.05 was considered statistically significant.

Results

The mean change in systolic blood pressure before and after cold pressor test (CPT) was less in obese (7.12 ± 5.28) as compared to non-obese subjects (10.38 ±6.35). This was statistically significant which indicates impaired sympathetic function in otherwise healthy obese.

Conclusion

The study concluded that blood pressure response to cold pressor test was reduced in obese compared to non-obese subjects indicating reduced sympathetic activity in healthy obese adults.