Varicella pneumonitis: clinical presentation and experience with acyclovir treatment in immunocompetent adults.

OBJECTIVE: Cases of varicella pneumonitis were reviewed to examine the effects of acyclovir therapy on outcome. METHODS: A retrospective chart review was done of all admissions of adults to two hospitals, between 1985 and 1995, because of complications of chickenpox. RESULTS: Fifteen patients were hospitalized for varicella pneumonitis during this period. No patient had a history of chickenpox as a child; all had a recent history (within 2-4 weeks prior to admission) of exposure to chickenpox in their family or neighborhood and developed respiratory symptoms 1 to 4 days after the appearance of the rash. Twelve patients (80%) had a history of cigarette smoking, and seven patients had a platelet count below the normal range. All patients were treated with intravenous acyclovir within 24 hours of admission, and all but one survived and were discharged from the hospital without comorbid conditions. The one mortality was attributed to bacterial superinfection. CONCLUSIONS: Acyclovir treatment may be of benefit for varicella pneumonitis, but no controlled trial has been performed to definitively answer this question.

Analysis of human antiviral cytotoxic T-lymphocyte responses for vaccine trials using cryopreserved mononuclear leukocytes: demonstration of feasibility with influenza virus-specific responses.

The feasibility of measuring virus-specific human cytotoxic T-lymphocyte (CTL) activity by using cryopreserved mononuclear leukocytes to support clinical vaccine trials was addressed. Autologous fresh and cryopreserved cells from the same sample of peripheral blood were used as sources of CTL precursors and were tested for influenza virus-specific activity. The data indicated that virus-specific CTL activity could be measured by using cryopreserved cells; this could also be done in assays that are designed to characterize the responsible effector cell population.

Persisting human immunodeficiency virus type 1 gp160-specific human T lymphocyte responses including CD8+ cytotoxic activity after receipt of envelope vaccines.

Mononuclear leukocytes (MNL) were obtained from vaccina-naive, non-human immunodeficiency virus (HIV) infected subjects who were vaccinated with HIV-1-derived recombinant (r) live vaccina-gp160, 4 of whom were boosted 1-2 years later with purified rgp160. MNL obtained after receipt of the vaccinia-gp160 alone showed persisting (> or = 1 year) gp160-specific lymphocyte proliferative responses and production of immune-specific interferon (IFN)-gamma. All 4 subjects who were boosted with rgp160 responded to the boost, including 2 whose cellular responses had waned prior to the boost. MNL from these 4 exhibited gp160-specific proliferative responses, IFN-gamma production, and cytotoxic T lymphocyte activity. The gp160-specific cytolysis was severely reduced or abolished by depletion of CD8+ cells and was not detected using HLA class I-mismatched target cells. Persisting (> or = 15 months after boost) HIV gp160-specific T cell recognition and functional responses can be induced by HIV-derived envelope vaccines.

Immediate vs. delayed treatment of group A beta-hemolytic streptococcal pharyngitis with penicillin V.

Three hundred six children with probable Group A beta-hemolytic streptococcal pharyngitis were enrolled in a randomized double blind trial to compare the effects of immediate vs. delayed treatment with oral penicillin V. Among the 229 culture-positive patients, 111 were randomly assigned to receive penicillin V immediately and 118 to receive a placebo for 48 to 52 hours followed by penicillin V. Patients were evaluated clinically for 48 to 52 hours following initiation of treatment. The Streptozyme test was used to measure acute to convalescent antibody titer. Both regimens resulted in a greater than 92% cure rate. Early treatment was associated with significantly fewer and milder signs and symptoms on Day 3 and a significantly lower rise in the antibody titer. On the other hand we found 8 (7%) relapses and 18 (16%) early and 14 (13%) late recurrences in this group; all were significantly higher than the corresponding numbers of 2 (2%), 6 (5%) and 4 (3%), respectively, in the late treatment group. This study shows the beneficial effect of early treatment with penicillin V on the clinical course of Group A beta-hemolytic streptococcal pharyngitis. This study also shows that delayed penicillin treatment may be associated with a lower incidence of subsequent Group A beta-hemolytic streptococcal pharyngitis.

A study of group B streptococcal carrier state during late pregnancy.

The carriage of Group B Streptococcus was investigated in 500 females in the third trimester of their pregnancy by culturing vaginal and rectal swabs and urine collected from each patient. A high rate of colonization was noted since 152 cases (30.4%) were found to harbor the organism, and 219 specimens (48%) from a total of 456 collected from these 152 cases were positive for Streptococcus agalactiae. Of the 219 positive specimens, 94 (42.9%) were vaginal swabs, 90 (41.1%) were rectal swabs and the remaining 35 (16%) were urine specimens. It is recommended that vaginal and rectal swab culture be used to detect carriers of group B streptococci, since using such a combination in this study revealed 91.4% of all positive cases.

The effect of the pH of various dairy products on the survival and growth of Brucella melitensis.

In this study we report the effect of the pH of various dairy products on the survival and growth of Brucella melitensis. The growth patterns of B. melitensis in broth media at different pHs (ranging between 3 and 9) were studied for up to four weeks, to standardize the growth of the organism at each pH. These growth patterns were compared with those of the same organism growing in different dairy products [milk, soft cheese, yoghurt, and buttermilk (shaneena)] under the same growth conditions. This showed that B. melitensis could survive for more than four weeks in broth at a pH of greater than or equal to 5.5, was inhibited in less than three weeks at pH 5 and in one day at pH 4, but could not survive in a pH of less than 4. In dairy products there was a marked drop in the total viable count, and the organism could not be detected after short periods of time. After 72 hours B. melitensis could be detected only in soft cheese, but it was not detectable in any of the dairy products tested after 96 hours. Thus, this study has shown that the survival of B. melitensis in the different dairy products was inversely proportional to the pH of the product.

Recolonization of anesthetic instruments after regular treatment with potentially pathogenic organisms.

Anesthetic instruments are classified as classes B with regard to sterilization status. This means that washing with soap and water or other detergents is sufficient for reuse. A prospective study was conducted over a 6 month period in the operating (rooms) theatres at Princess Basma Teaching Hospital on anesthetic instruments including laryngoscopes, oxygen masks, airways, tracheal tubes and suction catheters. Fifteen different samples were taken randomly at different sites on these instruments after they had been prepared conventionally for use, and these samples were cultured for bacterial contamination (e.g. P. Aeruginosa). The results showed that potentially pathogenic bacteria were colonizing these instruments. It was concluded that these instruments are important vehicles for transmitting various agents of infection and play an important role in causing nosocomial infections. It is recommended that more effective methods be used for sterilizing these instruments.

New observations regarding killing of fibroblasts infected with herpes simplex virus: cooperation between elutable factor and peripheral mononuclear cells.

With a standard chromium release assay, natural killing (NK) activity of peripheral mononuclear cells (PMCs) from 28 individuals was compared based on the ability of sera to support antibody-dependent cell-mediated cytotoxicity (ADCC) for cells infected with herpes simplex virus (HSV). PMCs from all 20 individuals whose sera produced ADCC were capable of killing HSV-infected cells compared with none of the PMCs from the eight individuals whose sera did not produce ADCC (mean specific release, 33.2% vs. 6.8%). Results could not be explained by contaminating serum in the assay or by ineffective NK by the PMCs from the eight negative subjects because many of them killed the k562 myeloid cell line as effectively as PMCs from other individuals. In addition, NK could be eliminated by preincubation of effector cells at 37 C, and the capacity to kill by PMCs could be reconstituted by incubation in serum. Killing was more a function of source of serum rather than source of cells.

Determination of mono-, di- and polyamines in foods using a single-column amino acid auto-analyzer.

A fully automated, rapid and sensitive method was developed to analyze fourteen different biogenic amines in food. Using a Technicon C4 ion-exchange resin column (20 m X 0.5 cm), adapted to an automatic Technicon TSM amino acid analyzer, the following amines were separated and quantified: adrenaline, noradrenaline, 1,3-diaminopropane, putrescine, cadaverine, histamine, spermidine, dopamine, spermine, agmatine, tyramine, serotonin, phenethylamine and tryptamine. Five buffers were required to elute the amines using a gradient of pH from 5.6 to 12.7; the column temperature was maintained at 65 degrees C. The method was also assayed on ground beef, cheese and wine samples. Amines from cheese and ground beef samples were extracted with 0.6 M perchloric acid. No extraction of wine samples was necessary.