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Biomedical subjects

S Allen

Publications and source records attributed to S Allen.

At least 145 records · Page 8Linked to original sources
PubMed1994

Beta 2-microglobulin as a predictor of death in HIV-infected women from Kigali, Rwanda.

OBJECTIVE: To determine if beta 2-microglobulin (beta 2M) predicts death among HIV-infected African women. DESIGN: Nested case-control study. SETTING: Kigali, Rwanda. PARTICIPANTS: Two hundred and five seroprevalent women known to be HIV-infected since 1986-1987; 67 of whom died of HIV disease (cases) and 138 were alive (controls) as of November 1991. In addition, 128 women who seroconverted between 1986 and 1991. MAIN OUTCOME MEASURES: HIV serology, clinical signs and symptoms of HIV disease, hematology variables, and beta 2M concentration. RESULTS: beta 2M concentration increased over time (P < 0.001) in the seroprevalent women and seroconvertors. The average rate of beta 2M increase in women who died was 0.5 compared with 0.3 mg/l/year in the vital, seroprevalent women (P = 0.07). The strongest independent predictors of death were the rate of change of beta 2M (mg/l/year) [odds ratio (OR), 3.4; 95% confidence interval (CI), 1.7-6.8] and baseline beta 2M concentration (mg/l) [OR, 1.6; 95% CI, 1.2-2.1]. The rate of death for women with beta 2M concentration > or = 7.0 mg/l and a rate of change of beta 2M > or = 0.4 mg/l/year was 7.3 times higher than for women with beta 2M concentration < 7.0 mg/l and a rate of change of beta 2M of < 0.4 mg/l/year (95% CI, 3.1-17.2). The estimated median time from seroconversion to death assuming a constant rate of change of beta 2M was 10.6 years (95% CI, 9.9-11.2) for this cohort of HIV-infected women. CONCLUSIONS: Elevated beta 2M and a high rate of beta 2M increase were strongly associated with mortality among HIV-infected African women. Based on survival estimates using the rate of change of beta 2M, HIV-infected African women have similar survival compared with HIV-infected adults in the United States.

Adolescent↗
PubMed1994

Pulmonary cryptococcosis associated with HIV-1 infection in Rwanda: a retrospective study of 37 cases.

OBJECTIVES: To study the demographic, clinical, radiographic and diagnostic features, the clinical course and therapeutic response of pulmonary cryptococcosis in HIV-1-infected patients. DESIGN: Retrospective review. SETTING: The Department of Medicine of an urban reference hospital in Central Africa. METHODS: All the records of HIV-1-infected patients with pulmonary cryptococcosis were reviewed retrospectively with regard to the parameters described above. RESULTS: Over a 3-year period, pulmonary cryptococcosis was diagnosed in 37 HIV-1-infected Rwandan patients (21 men, 16 women; mean age, 35 years; range, 26-55 years). Twenty-nine patients (78%) had primary pulmonary cryptococcosis. Cough (94%), weight loss (65%), fever (51%), dyspnoea (46%), thoracic pain (30%), headache (13%) and haemoptysis (8%) were the predominant clinical findings. A diffuse interstitial infiltrate on chest radiograph was observed in 76% of the patients, an alveolar pattern in 19%, mediastinal and/or hilar adenopathy in 11%, nodules and pleural effusion each in 5%. Bronchoalveolar lavage, with a yield of 82%, was found to be the most sensitive diagnostic procedure. Screening of cryptococcal antigen in the serum failed to detect cases of primary pulmonary cryptococcosis. Twelve patients with primary pulmonary cryptococcosis treated with itraconazole as acute and maintenance therapy were all protected against disseminated cryptococcal disease; seven out of 10 (70%) of those who did not receive a specific anticryptococcal drug developed disseminated cryptococcal disease. CONCLUSION: Pulmonary cryptococcosis is not a rare complication of HIV-1 infection in Rwanda. Its clinical and radiographic patterns are non-specific and bronchoalveolar lavage is the procedure of choice for its diagnosis. The natural history of untreated primary pulmonary cryptococcosis is disseminated cryptococcal disease. Itraconazole is highly effective in the prevention of disseminated cryptococcal disease in patients with primary pulmonary cryptococcosis.

AIDS-Related Opportunistic Infections↗
PubMed1994

A telephone survey of medical patients 1 week after discharge from hospital.

The telephone is an effective means of communication and its use is growing as a means of offering members of the public access to health-care agencies for advice and support. Acute hospital beds are at a premium and as lengths of stay in hospital continue to fall there is an increasing need for effective discharge planning and post-discharge support. Eighty-five patients (58 men and 27 women) were interviewed over the telephone 1 week after discharge from a medical ward. Over half of the patients reported health problems and one-fifth reported social problems. Almost half of the patients sought advice. Telephone follow-up would appear to be a useful means of monitoring a patient's progress and providing an opportunity for patients seeking, or nurses offering, advice and support.

Adult↗
PubMed1994

Pituitary apoplexy after stimulation tests.

Pituitary apoplexy occurs after infarction of a non-neoplastic pituitary or sudden expansion of an adenoma following haemorrhage or infarction. It usually occurs spontaneously but can follow a number of causes including pituitary stimulation tests. Since this complication is potentially life-threatening, the benefits of subjecting patients who might have pituitary tumours to such tests should be considered.

Aged↗
PubMed1994

Pulmonary disease associated with the human immunodeficiency virus in Kigali, Rwanda. A fiberoptic bronchoscopic study of 111 cases of undetermined etiology.

All human immunodeficiency virus type 1 (HIV-1) infected adult patients referred to the Division of Pulmonary Diseases of the Centre Hospitalier de Kigali, Rwanda for evaluation of a pulmonary disease of undetermined etiology (PDUE) were investigated by fiberoptic bronchoscopy using both bronchoalveolar lavage (BAL) and transbronchial biopsy (TBB). During a 10-mo period 111 HIV-1 infected patients with PDUE were examined, of whom 47 (42%) fulfilled the World Health Organization (WHO) clinical case definition for acquired immunodeficiency syndrome (AIDS) and seven (6%) had an AIDS-defining illness. Nonspecific interstitial pneumonitis was diagnosed in 42 (38%) patients, tuberculosis in 25 (23%), cryptococcosis in 14 (13%), Kaposi's sarcoma (KS) in 10 (9%), Pneumocystis carinii pneumonia (PCP) in five (5%). The diagnosis remained undetermined in 18 (16%) patients. Chest radiograph patterns were generally nonspecific. TBB and BAL had diagnostic yields of 82 and 26% of all final diagnoses, respectively. Our study on Rwandese HIV-1-infected patients with PDUE provides evidence for a large spectrum of pulmonary diseases with relative frequencies differing strikingly from those in developed countries. Detailed investigations confirm the rarity of PCP in Africa and highlight nonspecific interstitial pneumonitis as the predominant diagnosis of PDUE. Empiric antituberculosis treatment is justified in the absence of clinical manifestations suggestive of a specific diagnosis and while awaiting the results of the diagnostic procedures. Primary prophylaxis for PCP would not be appropriate in Africa.

Adult↗
PubMed1994

Cancer incidence and mortality among African Americans.

In the future, the largest proportional increase in the population will be among minority groups. To date, there are a number of studies which document the disparities in cancer incidence and survival existing between white Americans and minorities, especially African Americans. African Americans have the highest cancer incidence and mortality rates in the United States. Much of this difference can be directly related to socioeconomic status. There are also cultural differences which result in differing attitudes towards health care. In the future, interventions designed to encourage cancer prevention and screening behaviors must seek to overcome the barriers to access in a culturally sensitive fashion.

Adolescent↗
PubMed1993

The relative contribution of individual polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzo-p-furans (PCDFs) to toxic equivalent values derived for bulked human adipose tissue samples from Wales, United Kingdom.

Five bulked human adipose tissue samples were analyzed for individual polychlorinated biphenyl (PCB) congeners (including selected non-ortho-substituted compounds) and polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs). Mean sigma PCB and sigma PCDD/F (tetra-through octachlorinated homologues) concentrations were 0.75 microgram/g and 1.22 ng/g adipose tissue respectively. Both the congener patterns and levels detected were similar to those reported by laboratories in other industrialised countries. Each sample comprised of tissue taken from donors within a given locality. However, no obvious relationships were apparent between sampling area, absolute concentrations and congener pattern of PCBs and PCDD/Fs. The contribution of individual PCDD/F and non-ortho-(o), mono-o-, and di-o-substituted PCB congeners to the total calculated toxic equivalent values (sigma TEQ) was assessed for each sample. The main contributions to the sigma TEQ were the mono-o-substituted PCB congeners #118 (TEQ = 42.5 pg/g of lipid), #156 (TEQ = 24.8 pg/g) and #105 (TEQ = 20.7 pg/g), followed by 1,2,3,6,7,8-HxCDD (TEQ = 18.2 pg/g), 2,3,4,7,8-P5CDF (TEQ = 12 pg/g), 1,2,3,7,8-P5CDD (TEQ = 11.5 pg/g), and the non-o-substituted PCB congener #126 (TEQ = 11.3 pg/g). Collectively, these compounds accounted for 80% of the sigma TEQ values. Based on the TEFs proposed by Safe (1990), the overall TEQs calculated for the monitored PCBs, were twice those due to sigma PCDD/Fs.

Adipose Tissue↗
PubMed1993

Bone metabolism in children with asthma treated with inhaled beclomethasone dipropionate.

Previous studies have shown that inhaled corticosteroids can affect bone metabolism in adults. A study to assess the effect of inhaled beclomethasone, 300 to 800 micrograms/day for at least 6 months (mean 25 months), was therefore undertaken in children. In part 1 of the study, 18 children with asthma, aged 4 to 17 years (mean 10.1 years), were compared with an age- and sex-matched group of children with asthma not treated with corticosteroids. In part 2, eight more pairs were compared. Comparisons were also made with 61 healthy children. Bone mineral density measured by radiographic absorptiometry, and bone mineral content measured by single-photon absorptiometry and by dual-energy x-ray absorptiometry, showed no significant differences. Serum levels of calcium, magnesium, zinc, total alkaline phosphatase, bone specific alkaline phosphatase, parathyroid hormone, 25-hydroxyvitamin D, and 1,25-dihydroxyvitamin D also showed no differences. The activity of tartrate-resistant acid phosphatase, a marker of bone resorption, was significantly lower in the beclomethasone group than in both the asthma control and the normal control groups, but urine calcium excretion did not differ. Patients with asthma had lower serum osteocalcin and higher serum copper levels than control subjects without asthma, but treatment with beclomethasone did not affect these values. We conclude that inhaled beclomethasone (up to 800 micrograms/day) does not reduce bone mineralization or increase bone resorption. Effects on bone formation were difficult to assess because asthma per se caused a significant reduction in osteocalcin, a sensitive marker of bone formation.

Acid Phosphatase↗
PubMed1993

Effects of an academic failure experience on subsequent performance on anagram and paired-associate tasks: differences among second-, fifth-, and eighth-grade children.

Failure on an academic task was experimentally induced in second-, fifth, and eighth-grade school children. The failure experience significantly retarded subsequent performance on an anagram task and a paired-associates task by second graders but not by fifth and eighth graders. Among the eighth-grade boys, performance on the paired-associates task was actually facilitated by the failure experience. It is suggested that the older students' greater experience with negative feedback in school accounts for their resistance to its negative effects.

Attention↗
PubMed1993

A phase II study of moderate hypothermia in severe brain injury.

Forty-six patients with severe nonpenetrating brain injury [Glasgow Coma Scale (GCS) 4-7] were randomized to standard management at 37 degrees C (n = 22) and to standard management with systemic hypothermia to 32 to 33 degrees C (n = 24). The two groups were balanced in terms of age (Wilcoxon's rank sum test, p > 0.95), randomizing GCS (chi-square test, p = 0.54), and primary diagnosis. Cooling was begun within 6 h of injury by use of cooling blankets. Metocurine and morphine were given hourly during induction and maintenance of hypothermia. Rewarming was at a rate of 1 degree C per 4 h beginning 48 h after intravascular temperature had reached 33 degrees C. Muscle relaxants and sedation were continued until core temperature reached 35 degrees C. There were no cardiac or coagulopathy-related complications. Seizure incidence was lower in the hypothermia group (Fisher's exact text, p = 0.019). Sepsis was seen more commonly in the hypothermia group, but difference was not statistically significant (chi-square test). Mean Glasgow Outcome Scale (GOS) score at 3 months after injury showed an absolute increase of 16% (i.e., 36.4-52.2%) in the number of patients in the Good Recovery/Moderate Disability (GR/MD) category as compared with Severe Disability/Vegetative/Dead (SD/V/D) (chi-square test, p > 0.287). Based on evidence of improved neurologic outcome with minimal toxicity, we believe that phase III testing of moderate systemic hypothermia in patients with severe head injury is warranted.

Adolescent↗
PubMed1993

Hospital-based versus community-based clinical education: comparing performances and course evaluations by students in their second-year pediatrics rotation.

BACKGROUND: Increasing use of outpatient settings for clinical education raises the question of their effectiveness compared with that of inpatient settings. METHOD: At the University of Minnesota Medical School-Minneapolis in 1987-88, the 190 second-year students participated in a six-week tutorial rotation introducing them to clinical pediatrics: 52 (27%) were in hospital settings and 138 (73%) were in community outpatient settings. Almost all the students (178) evaluated their rotations by responding to both structured and open-ended questions, using a Likert scale for the structured questions. At the completion of the second year, all 190 students took an objective structured clinical examination (OSCE) that included five pediatrics stations. Student's t-test was used to compare (1) the mean ratings the hospital-based and community-based students gave their pediatrics rotations and (2) the mean scores earned by the two groups of students on the five pediatrics stations in the OSCE. RESULTS: There were no statistically significant differences between (1) the two groups' mean ratings of the clinical experience overall or of the quality of teaching or (2) the groups' mean scores on any of the OSCE stations. CONCLUSION: That the hospital-based and community-based students performed comparably on the OSCE and gave similar evaluations of their pediatrics rotations supports the use of community practitioners to provide students with their initial clinical training. Moreover, community-based teaching sites replicate situations in which most students will eventually practice medicine.

Ambulatory Care↗
PubMed1993

Pleural effusion, tuberculosis and HIV-1 infection in Kigali, Rwanda.

OBJECTIVE AND METHODS: An increasing number of diagnoses of pleural effusions (PE) have been made over the last 8 years in the Department of Internal Medicine of the Centre Hospitalier de Kigali, Rwanda. In order to determine the aetiology of PE and to examine its possible association with HIV-1 infection, we performed an aetiological work-up, including thoracocentesis and pleural punch biopsy, of all new patients with PE of undetermined aetiology referred to the Division of Pulmonary Diseases of the Department of Internal Medicine of the Centre Hospitalier de Kigali between 14 September 1988 and 16 October 1989. HIV-1 serological testing was performed for most of the patients. RESULTS: A total of 127 patients (81 men, 46 women; mean age, 34 years; range, 16-71 years) with PE of undetermined aetiology were enrolled. Pleural tuberculosis was diagnosed in 110 (86%) and confirmed histologically and/or bacteriologically in 90 (82%). Of 98 pleural tuberculosis patients tested for HIV-1-antibody, 82 (83%) were HIV-1-seropositive. Metastatic cancer was responsible for PE in six (5%) patients, Kaposi's sarcoma in three, lymphoma in one (all four HIV-1-seropositive), anaplastic carcinoma in one, and adenocarcinoma in one (both HIV-1-seronegative). Non-tuberculous pneumonia was documented in five (4%) patients and was associated with HIV-1 infection in four. Other causes of PE were congestive heart failure (three patients), decompensated cirrhosis (one), constrictive percarditis (one), or undetermined (one); only one of these patients was HIV-1-seropositive. CONCLUSIONS: We conclude that tuberculosis is the predominant cause of PE in our patients and is strongly associated with HIV-1 infection. Although less frequent, non-tuberculous pneumonia, Kaposi's sarcoma and lymphoma are other causes of HIV-1-associated PE. In an African area highly endemic for HIV-1 and Mycobacterium tuberculosis co-infection, PE should be considered a good marker of tuberculosis as well as HIV-1 infection.

AIDS-Related Opportunistic Infections↗